CURRENT Diagnosis and Treatment Pediatrics, (Current Pediatric Diagnosis & Treatment) 22nd Edition

26. Orthopedics

Mark A. Erickson, MD, MMM

Brendan Caprio, BS

Orthopedics is the medical discipline that deals with disorders of the musculoskeletal system. Patients with orthopedic problems generally present with one or more of the following complaints: pain, swelling, loss of function, or deformity. While the history reveals the patient’s expectation, physical examination and radiographic imaging are vitally important features of orthopedic diagnosis.

DISTURBANCES OF PRENATAL ORIGIN

image ESSENTIALS OF DIAGNOSIS &TREATMENT

image Conditions are present at birth.

image Multiple organ systems may be involved.

image Treatment is aimed at maximizing function.

CONGENITAL AMPUTATIONS & LIMB DEFICIENCIES

Congenital amputations may be due to teratogens (eg, drugs or viruses), amniotic bands, or metabolic diseases (eg, maternal diabetes). Limb deficiencies are rare with an overall prevalence for all types of limb deficiencies of 0.79 per 1000. The most common cause of limb deficiencies is vascular disruption defects (prevalence of 0.22 per 1000). As a group, upper limb deficiencies occur more frequently than lower limb deficiencies, but the single most frequent form of limb deficiency is congenital longitudinal deficiency of the fibula. Children with congenital limb deficiencies, such as absence of the femur, tibia, or fibula, have a high incidence of other congenital anomalies, including genitourinary, cardiac, and palatal defects. Deficiencies usually consist of a partial absence of structures in the extremity along one side. For example, in radial club hand, the entire radius is absent, but the thumb may be either hypoplastic or completely absent. The effect on structures distal to the deficiency varies. Complex tissue defects are virtually always associated with longitudinal bone deficiency since associated nerves and muscles are not completely represented when a bone is absent.

imageTreatment

Limb lengthening and/or contralateral limb shortening can be used to treat less severe deficiencies. More severe deficiencies are treated with a prosthesis to compensate for the length discrepancy. For certain severe anomalies, operative treatment to remove a portion of the malformed extremity (eg, foot) is indicated to allow for early prosthetic fitting. In these instances, early prosthetic fitting allows for maximization of function.

Typically, a lower extremity prosthesis would be fit at about 1 year of age allowing the child to begin ambulation at an appropriate developmental age. The prosthesis is well accepted since it becomes necessary for balancing and walking. In unilateral upper extremity amputation, the child benefits from the use of a passive mitten type prosthesis starting as early as 6 months of age. Early fitting has the advantage of instilling an accustomed pattern of proper length and bimanual manipulation. Although myoelectric prostheses have a technologic appeal, the majority of patients find the simplest construct to be the most functional. Children quickly learn how to function with their prostheses and can lead active lives.

Gold NB, Westgate MN, Holmes LB: Anatomic and etiological classification of congenital limb deficiencies. Am J Med Genet Part A 2011;155:1225–1235 [PMID: 21557466].

Klaassen Z et al: Supernumerary and absent limbs and digits of the lower limb: a review of literature. Clin Anat 2011;24:570–575 [PMID: 21647959].

Walker JL et al: Adult outcomes following amputation or lengthening for fibular deficiency. J Bone Joint Surg Am 2009;91(4):797–804 [PMID: 19339563].

DEFORMITIES OF THE EXTREMITIES

Metatarsus Adductus

Metatarsus adductus, a common congenital foot deformity, is characterized by inward deviation of the forefoot. When the deformity is more rigid, it is characterized by a vertical crease in the medial aspect of the arch. Angulation occurs at the base of the fifth metatarsal causing prominence of this bone. Most flexible deformities are secondary to intrauterine positioning and usually resolve spontaneously. Several investigators have noticed that 10%–15% of children with metatarsus adductus have hip dysplasia; therefore, a careful hip examination is necessary. The etiology of rigid deformities is unknown. If the deformity is rigid and cannot be manipulated past the midline, it is worthwhile to perform serial casting, with cast changes in 1–2-week intervals, to correct the deformity. Corrective shoes do not live up to their name; however, they can be used to maintain the correction obtained by casting.

Sankar WN, Weiss J, Skaggs DL: Orthopedic conditions in the newborn. J Am Acad Orthop Surg 2009;17(2):112–122 [PMID: 19202124].

Clubfoot (Talipes Equinovarus)

Classic talipes equinovarus, or clubfoot, requires three features for diagnosis: (1) plantar flexion of the foot at the ankle joint (equinus), (2) inversion deformity of the heel (varus), and (3) medial deviation of the forefoot (adductus). Clubfoot occurs in approximately 1 per 1000 live births. The three major categories of clubfoot are idiopathic, neurogenic, and those associated with syndromes such as arthrogryposis and Larsen syndrome. Infants with a clubfoot should be examined carefully for associated anomalies, especially of the spine. Idiopathic club feet may be hereditary.

imageTreatment

Manipulation of the foot to stretch the contracted tissues on the medial and posterior aspects, followed by casting to hold the correction is the preferred treatment. Serial castings are typically performed on a weekly basis for 6–8 weeks. When instituted shortly after birth, correction is rapid. If treatment is delayed, the foot tends to become more rigid within a matter of days. Casting treatment requires patience and experience, but fewer patients require surgery when attention is paid to details of the Ponseti technique. After full correction is obtained, a night brace is necessary for long-term maintenance of correction. Recent studies indicate that there is poor compliance with brace use following intervention with the Ponseti technique. If the foot is rigid and resistant to cast treatment, surgical release and correction are appropriate. Approximately 15%–50% of patients require a surgical release.

Dobbs MB, Gurnett CA: Update on clubfoot: etiology and treatment. Clin Orthop Relat Res 2009;467(5):1146–1153 [PMID: 19224303].

Ramirez N, Flynn JM, Fernandez S, Seda W, Macchiavelli RE: Orthosis noncompliance after the Ponseti method for the treatment of idiopathic clubfeet: a relevant problem that needs reevaluation. J Pediatr Orthop 2011;31(6):710–715 [PMID: 21841450].

Developmental Dysplasia of the Hip Joint

Dysplasia is the term used to describe abnormal growth or development. Dysplasia of the hip encompasses a spectrum of conditions where an abnormal relationship exists between the proximal femur and the acetabulum. In the most severe condition, the femoral head is not in contact with the acetabulum and is classified as a dislocated hip. In a dislocatable hip, the femoral head is within the acetabulum but can be dislocated with a provocative maneuver. A subluxatable hip is one in which the femoral head comes partially out of the joint with a provocative maneuver. Acetabular dysplasia is used to denote insufficient acetabular development and is a radiographic diagnosis.

Congenital dislocation of the hip more commonly affects the left hip, occurring in approximately 1%–3% of newborns. At birth, both the acetabulum and femur are underdeveloped. Dysplasia is progressive with growth unless the instability is corrected. If the dislocation is corrected in the first few weeks of life, the dysplasia can be completely reversible and a normal hip will more likely develop. If the dislocation or subluxation persists with age, the deformity will worsen until it is not completely reversible, especially after the walking age. For this reason, it is important to diagnose the deformity and institute treatment early.

imageClinical Findings

Clinical diagnosis of dislocations in newborns is dependent on demonstrating the instability of the joint by placing the infant on his or her back and obtaining complete relaxation. As these clinical signs can be subtle, with a crying or upset infant they can be easily missed. The examiner’s long finger is then placed over the greater trochanter and the thumb over the inner side of the thigh. Both hips are flexed 90 degrees and then slowly abducted from the midline, one hip at a time. With gentle pressure, an attempt is made to lift the greater trochanter forward. A feeling of slipping as the head relocates is a sign of instability (Ortolani sign). When the joint is more stable, the deformity must be provoked by applying slight pressure with the thumb on the medial side of the thigh as the thigh is adducted, thus slipping the hip posteriorly and eliciting a palpable clunk as the hip dislocates (Barlow sign). Limited hip abduction of less than 60 degrees while the knee is in 90 degrees of flexion is believed to be the most sensitive sign for detecting a dysplastic hip. Clinical signs of instability are more reliable than radiographs for diagnosing developmental dislocation of the hip in the newborn. Ultrasonography is most useful in newborns, and can be helpful for screening high-risk infants, such as those with breech presentation or positive family history. Asymmetrical skin folds are present in about 25% of normal newborns and therefore are not particularly helpful to diagnosing hip dislocation.

The signs of instability become less evident after the first month of life. Contractures begin to develop about the hip joint, limiting abduction to less than 90 degrees. It is important to hold the pelvis level to detect asymmetry of abduction. If the knees are at unequal heights when the hips and knees are flexed, the dislocated hip will be on the side with the lower knee. Radiological examination becomes more valuable after the first 6 weeks of life, with lateral displacement of the femoral head being the most reliable sign. An acetabular index or angle can be measured on pelvis radiographs by drawing one line horizontally through the triradiate cartilage and another line starting at the triradiate cartilage and extending to the outer edge of the acetabulum. A normal angle would be less than 30 degrees. In mild cases, increased steepness of acetabular alignment (acetabular angle > 35 degrees) may be the only abnormality.

If dysplasia of the hip has not been diagnosed before the child begins to walk, there will be a painless limp and/or a lurch to the affected side. When the child stands on the affected leg, a dip of the pelvis will be evident on the opposite side, due to weakness of the gluteus medius muscle. This is called the Trendelenburg sign and accounts for the unusual swaying gait. In children with bilateral dislocations, the loss of abduction is almost symmetrical and may be deceiving. In children with incomplete abduction during the first few months of life, a radiograph of the pelvis is indicated. As a child with bilateral dislocation of the hips begins to walk, the gait is waddling. The perineum is widened as a result of lateral displacement of the hips, and there is flexion contracture as a result of posterior displacement of the hips. This flexion contracture contributes to marked lumbar lordosis, causing the greater trochanters to be easily palpable in their elevated position. Treatment is still possible in the first 2 years of life, but the results are not as good as with early treatment. In patients older than 2 years, more aggressive procedures like osteotomies are often necessary to create a more normal orientation and shape of the hip joint.

imageTreatment

Most unstable hips undergo spontaneous correction by 2–6 weeks of age. A Pavlik harness, which maintains reduction by placing the hip in a flexed and abducted position, can be easily used to treat dislocation or dysplasia diagnosed in the first few weeks or months of life. In order to be safely treated in a Pavlik harness, hips must be manually reducible with only gentle manipulation. Forced abduction, or reduction requiring extremes of motion for stability, can lead to avascular necrosis of the femoral head and is contraindicated. The use of double or triple diapers is ineffective. An orthopedic surgeon with experience managing the problem is best to supervise treatment.

In the first 4 months of life, reduction can be obtained by simply flexing and abducting the hip with a Pavlik harness; no other manipulation is usually necessary. In late cases, preoperative traction for 2–3 weeks may assist by relaxing soft tissues about the hip. Following traction, in which the femur is brought down opposite the acetabulum, reduction can typically be achieved, without force, under general anesthesia. A hip spica cast is used for 3 months after reduction. If the hip is not stable within a reasonable range of motion after closed reduction, open reduction is indicated. If reduction is done at an older age, operations to correct the deformities of the acetabulum and femur, as well as open reduction, may be necessary. Older children are more likely to experience complications from more extensive procedures.

Delaney LR, Karmazyn B: Developmental dysplasia of the hip: background and the utility of ultrasound. Semin Ultrasound CT MR 2011;32:151–156 [PMID: 21414550]

Sewell MD, Roendah K, Eastwood DM: Developental dysplasia of the hip. BMJ 2009;339:b4454. Doi: 10.1136/bmj.b4454 [PMID: 19934187].

Torticollis

Injury to the sternocleidomastoid muscle during delivery or disease affecting the cervical spine in infancy, such as congenital vertebral anomalies, may cause torticollis. When contracture of the sternocleidomastoid muscle causes torticollis, the chin is rotated to the side opposite of the affected muscle, causing the head to tilt toward the side of the contracture. A mass felt in the midportion of the sternocleidomastoid muscle in a newborn is likely a hematoma or developmental fibroma, rather than a true tumor.

If the deformity is left untreated, a striking facial asymmetry can persist. Passive stretching is an effective treatment in up to 97% of all cases. If the deformity does not correct with passive stretching during the first year of life, surgical release of the muscle origin and insertion can be an effective treatment option. Excising the “tumor” of the sternocleidomastoid muscle is unnecessary and creates an unsightly scar.

Torticollis is occasionally associated with congenital deformities of the cervical spine. Radiographs of the spine are indicated in most cases where such anomalies are suspected. In addition, there is a 15%–20% incidence of associated hip dysplasia.

Acute torticollis may follow upper respiratory infection or mild trauma in children. Upper respiratory infections may lead to swelling in the upper cervical spine, particularly at the C1-C2 region. This swelling renders the C1-C2 articulation susceptible to rotatory subluxation, which commonly presents as a clinical picture of torticollis. Rotatory subluxation of the upper cervical spine requires computed tomography for accurate assessment. Traction or a cervical collar usually results in resolution of the symptoms within 1 or 2 days. Other causes of torticollis include spinal cord and cerebellar tumors, syringomyelia, and rheumatoid arthritis.

Sankar WN, Weiss J Skaggs DL: Orthopedic conditions in the newborn. J Am Acad Orthop Surg 2009;17(2):112–122 [PMID: 19202124].

Tomczak KK, Rosman NP: Torticollis. J Child Neurol 2013;28(3):365–378 [PMID: 23271760].

GENERALIZED DISORDERS OF SKELETAL OR MESODERMAL TISSUES

Arthrogryposis Multiplex Congenita (Amyoplasia Congenita)

imageClinical Findings & Diagnosis

Arthrogryposis multiplex congenita (AMC) consists of incomplete fibrous ankylosis (usually bilateral) of many or all joints of the body. AMC affects both genders equally and occurs in approximately 1 in 2–3000 live births. Upper extremity contractures usually consist of adduction of the shoulders; extension of the elbows; flexion of the wrists; and stiff, straight fingers with poor muscle control of the thumbs. Common deformities of the lower extremities include dislocation of the hips, extension contractures of the knees, and severe club feet. The joints are fusiform and the joint capsules decreased in volume due to lack of movement during fetal development. Muscle development is poor, and may be represented only by fibrous bands. Various investigations have attributed the basic defect to an abnormality of muscle or lower motor neurons.

It is possible to diagnose AMC during routine fetal ultrasound scanning. The fetus will be in an abnormal position or lack mobility. Early diagnosis helps the family and provider with delivery planning and counseling.

imageTreatment

Passive mobilization of joints is the early treatment. Prolonged casting results in further stiffness and is not indicated. Removable splints combined with vigorous therapy are the most effective conservative treatment; however, surgical release of the affected joints is often necessary. Clubfoot associated with arthrogryposis is very stiff and nearly always requires surgical correction. Knee surgery, including capsulotomy, osteotomy, and tendon lengthening, is used to correct deformities. In young children, a dislocated hip may be reduced operatively by a medial approach. Multiple operative hip procedures are contraindicated, as they may further stiffen the hip dislocation with consequent impairment of motion. Affected children are often able to walk if the dislocations and contractures are reduced surgically. The long-term prognosis for physical and vocational independence is guarded. These patients have normal intelligence, but they have such severe physical restrictions that gainful employment is hard to find.

Bamshad M, Van Heest AE, Pleasure D: Arthrogryposis: a review and update. J Bone Joint Surg Am 2009;91(Suppl 4):40–46 [PMID: 19571066].

Kalampokas E, Kalampokas T, Sofoudis C, Deligeoroglou E, Botsis D: Diagnosing arthrogyrposis multiplex congenital: a review. ISRN Obstet Gynecol 2012;2012:264918 [PMID: 23050160].

Marfan Syndrome

Marfan syndrome is a connective tissue disorder characterized by unusually long fingers and toes (arachnodactyly); hypermobility of the joints; subluxation of the ocular lenses; other eye abnormalities, including cataract, coloboma, megalocornea, strabismus, and nystagmus; a high-arched palate; a strong tendency to scoliosis (60% of all those diagnosed); pectus carinatum (an outward protrusion of the sternum); and thoracic aortic aneurysms due to weakness of the media of the vessels (see Chapter 37). Fibrillin-1 gene mutations are commonly associated with Marfan syndrome. Serum mucoproteins may be decreased, and urinary excretion of hydroxyproline increased. The condition is easily confused with homocystinuria, because the phenotypic presentation is nearly identical. The two diseases are differentiated by detecting homocystine in the urine of patients with homocystinuria.

Treatment is usually supportive and includes management of blood pressure and restriction of physical activity. Scoliosis may involve more vigorous treatment by bracing or spine fusion. The long-term prognosis has improved for patients since the development of better treatment of their aortic aneurysms.

Lebreiro A et al: Marfan syndrome clinical manifestations, pathophysiology and, new outlook on drug therapy. Rev Port Cardiol 2010;29(6):1021–1036 [PMID: 20964113].

Yuan SM, Jing H: Marfan syndrome: an overview. San Paulo Med J 2010;128(6):360–366 [PMID: 21308160].

Klippel-Feil Syndrome

Klippel-Feil syndrome is characterized by failure of segmentation of some or all of the cervical vertebrae. Multiple congenital spinal anomalies may be present, with hemivertebrae and scoliosis. The neck is short and stiff, the hairline is low, and the ears are low-set. Congenital scoliosis, cervical rib, spina bifida, torticollis, web neck, high scapula, renal anomalies, and deafness are commonly associated defects. Renal ultrasound as well as a hearing test are indicated if there is evidence of abnormal renal function. Surgical intervention is necessary to prevent neurologic injury in symptomatic patients who present with unstable spinal anomalies. If asymptomatic, a spine surgeon will determine if surgical intervention is warranted after review of patient’s age, history, and activity level. Spinal arthrodesis is indicated if progressive scoliotic deformities develop.

Kim HJ: Cervical spine anomalies in children and adolescents. Curr Opin Pediatr 2013;25(1):72–77 [PMID: 23263023].

Sprengel Deformity

Sprengel deformity is a congenital condition where one or both scapulas are elevated and hypoplastic. The deformity prevents the arm from raising completely on the affected side, and torticollis may be an associated finding. The deformity occurs alone or in association with Klippel-Feil syndrome or scoliosis and rib abnormalities. If the deformity is functionally limiting, the scapula may be surgically relocated closer to the normal anatomic position. Surgical intervention improves cosmetic appearance and function.

Harvey EJ, Bernstein M, Desy NM, Saran N, Ouellet JA: Sprengel deformity: pathogenesis and management. J Am Acad Orthop Surg 2012;20(3):177–186 [PMID: 22382290].

Mooney JF 3rd, White DR, Glazier S: Previously unreported structure in Sprengel deformity. J Pediatr Orthop 2009;29(1):26–28 [PMID: 19098640].

Osteogenesis Imperfecta

Osteogenesis imperfecta is a rare genetic connective tissue disease characterized by multiple and recurrent fractures. The incidence is 1 in 15,000–20,000. Clinical features of the disease lead to diagnosis in the majority of cases. The severe fetal type (osteogenesis imperfecta congenita) is distinguished by multiple intrauterine or perinatal fractures. Moderately affected children have numerous fractures and exhibit dwarfism as a result of their acquired bone deformities and growth retardation. Fractures begin to occur at different times and in variable patterns after the perinatal period, resulting in fewer fractures and deformities relative to severe cases. Cortical thickness is reduced in the shafts of the long bones, and accessory skull bones that are completely surrounded by cranial sutures (wormian bones) are present in the skull. Blue sclerae, thin skin, hyperextensibility of ligaments, otosclerosis with significant hearing loss, and hypoplastic and deformed teeth are characteristic of osteogenesis imperfecta. Cardiovascular and respiratory problems are the most common causes of morbidity and mortality in adulthood. Intelligence is not affected. Affected patients are sometimes suspected of having suffered abuse. Osteogenesis imperfecta should be ruled out in any case of potential nonaccidental trauma.

Molecular genetic studies have identified more than 150 mutations of the COL1A1 and COL1A2 genes, which encode for type I procollagen. Ninety percent of cases occur as the result of a spontaneous mutation; in these families the likelihood of a second affected child is negligible. Among the other 10%, a recessive mode of inheritance has been identified in 2%–5%.

Bisphosphonates have been shown to decrease the incidence of fractures. Surgical treatment involves deformity correction of the long bones. Multiple intramedullary rods have been used to prevent deformity from fracture malunion. Patients are often confined to wheelchairs during adulthood.

Basel D, Steiner RD: Osteogenesis imperfecta: recent findings shed new light on this once well-understood condition. Gene Med 2009;11(6):375–385 [PMID: 195334842].

Greeley CS, Donaruma-Kwoh M, Vettimattam M, Lobo C, Williard C, Mazur L: Fractures at diagnosis in infants and children with osteogenesis imperfect. J Pediatr Orthop 2013;33(1):32–36 [PMID: 23232376].

Rohrbach M, Giunta C: Recessive osteogenesis imperfecta: clinical, radiological, and molecular findings. Am J Med Genet C Semin Med Genet 2012;160C (3):175–189 [PMID: 22791419].

Osteopetrosis (Osteitis Condensans Generalisata, Marble Bone Disease, Albers-Schönberg Disease)

Osteopetrosis is a rare disorder of osteoclastic resorption of bone, resulting in abnormally dense bones. The reduced marrow spaces result in anemia. There are two types: a milder autosomal dominant type and a more malignant autosomal recessive type. The findings may appear at any age. Radiologic examination shows increased bone density and transverse bands in the shafts, clubbing of ends, and vertical striations of long bones. Thickening about the cranial foramina is present, and heterotopic calcification of soft tissues is possible. Diminished life expectancy is seen in severe infantile forms.

Treatment is largely symptomatic. The most severe autosomal recessive forms of osteopetrosis can be treated successfully by hematopoietic stem cell transplantation.

Michou L, Brown JP: Genetics of bone diseases Paget’s disease, fibrous dysplasia, osteopetrosis, and osteogenesis imperfecta. Joint Bone Spine 2011;(78):252–258 [PMID: 20855225].

Achondroplasia (Classic Chondrodystrophy)

Achondroplasia is the most common form of short-limbed dwarfism. The upper arms and thighs are proportionately shorter than the forearms and legs. Skeletal dysplasia is suspected based on abnormal stature, disproportion, dysmorphism, or deformity. Measurement of height is an excellent clinical screening tool. Findings frequently include bowing of the extremities, a waddling gait, limitation of motion of major joints, relaxation of the ligaments, short stubby fingers of almost equal length, frontal bossing, midface hypoplasia, otolaryngeal system dysfunction, moderate hydrocephalus, depressed nasal bridge, and lumbar lordosis. Intelligence and sexual function are normal. While this disorder has an autosomal dominant transmission pattern, 80% of cases result from a random mutation in the fibroblast growth factor receptor-3 (FGFR3) gene. Radiographs demonstrate short, thick tubular bones and irregular epiphysial plates. The ends of the bones are thick, with broadening and cupping. Epiphysial ossification may be delayed. Due to diminished growth in the spinal pedicles, the spinal canal is narrowed (congenital stenosis), and a herniated disk in adulthood may lead to acute paraplegia. Growth hormone is given to some children with bone dysplasia. Limb lengthening is possible, but controversial.

Shirley ED, Ain MC: Achondroplasia: manifestations and treatment. J Am Acad Orthop Surg 2009;(17):231–241 [PMID: 19307672].

Osteochondrodystrophy (Morquio Disease)

Morquio disease is an autosomal recessive disorder affecting mucopolysaccharide storage. Skeletal abnormalities include shortening of the spine, kyphosis, scoliosis, shortened extremities, pectus carinatum, genu valgum or “knock knees,” and a hypoplastic odontoid with atlantoaxial instability. Appearance is generally normal at birth, with deformities developing between ages 1 and 4 years as a result of abnormal deposition of mucopolysaccharides. Increased urinary glycosaminoglycan levels are associated with increased severity.

Radiographs demonstrate wedge-shaped flattened vertebrae and irregular, malformed epiphyses. The ribs are broad and have been likened to canoe paddles. The lower extremities are more severely involved than the upper extremities. Progressive hip subluxation, genu valgum, and ankle valgus often require surgical intervention.

The major treatment issue revolves around prevention of cervical myelopathy. Bone marrow transplantation has been successful in alleviating some symptoms. Enzyme replacement therapy has emerged as another possible treatment option for afflicted patients. Prognosis depends on age of onset.

Tuberville S et al: Clinical outcomes following hematopoietic stem cell transplantation for the treatment of mucopolysaccharidosis VI. Mol Genet Metab 2011;2:111–115 [PMID: 20980181].

Valayannopoulos V et al: Mucopolysaccharidosis VI. Orphanet J Rare Dis. 2010 Apr 12;5:5. doi: 10.1186/1750-1172-5-5. Review [PMID: 20385007].

GROWTH DISTURBANCES OF THE MUSCULOSKELETAL SYSTEM

SCOLIOSIS

Scoliosis is characterized by lateral curvature of the spine associated with rotation of the involved vertebrae and classified by its anatomic location, in either the thoracic or lumbar spine, with rare involvement of the cervical spine. The convexity of the curve is designated right or left. A right thoracic scoliosis would denote a thoracic curve with convexity to the right. This is the most common type of idiopathic curve. Kyphosis or posterior curvature of the spine is normal in the thoracic area, although excessive curvature is pathologic. Anterior curvature of the spine, or lordosis, is normal in the lumbar and cervical spine regions.

Eighty percent of cases of scoliosis are idiopathic. Idiopathic scoliosis typically develops around age 8–10 years, with progression occurring during periods of rapid skeletal growth. In rare instances, infantile scoliosis may be seen in children age 3 years or younger; idiopathic infantile scoliosis is much more common in Great Britain than in the United States. In infantile scoliosis, if the rib-vertebral angle of Mehta is less than 20 degrees, the curve will likely resolve spontaneously. If the angle is greater, the curve will likely progress.

Idiopathic scoliosis is about four or five times more common in girls. The disorder is usually asymptomatic in the adolescent years, but severe curvature can progress during adulthood causing pain or, in extreme cases, diminished pulmonary function as a result of reduced lung volumes due to deformity of the rib cage. The screening examination for scoliosis is performed by having the patient bend forward 90 degrees with the hands joined in the midline. Asymmetry of the height of the ribs or paravertebral muscles on one side indicates rotation of the trunk associated with lateral curvature. Because 30% of family members are also affected, siblings of an affected child should be examined.

Neurofibromatosis, Marfan syndrome, cerebral palsy, muscular dystrophy, poliomyelitis, and myelodysplasia are among several diseases that may be present with an associated scoliosis.

Congenital vertebral anomalies such as hemivertebra or unilateral vertebral bar account for 5%–7% of all scoliosis. These curves are more rigid than the more common idiopathic curve and will often increase with skeletal growth, especially during adolescence.

Olisthetic scoliosis may result from pressure on the spinal cord or roots by infectious processes or herniation of the nucleus pulposus; the underlying cause must be sought. Secondary curvature will resolve as the primary problem is treated.

imageClinical Findings

A. Symptoms and Signs

Scoliosis in adolescents does not typically cause significant pain. If a patient has significant pain, then the source of the pain should be sought in order to rule out the possibility of some other disorder such as infection or tumor. Deformity of the rib cage and asymmetry of the waistline are clinically evident for curvatures of 30 degrees or more. Lesser curves may be detected through the forward bending test, which is designed to detect early abnormalities of rotation that may not be apparent when the patient is standing erect.

B. Imaging

Radiographs taken of the entire spine in the standing position in both the anteroposterior and lateral planes are the most valuable for diagnosis. Usually a primary curve is evident with compensatory curvature to balance the body. At times two primary curvatures may be seen (usually in the right thoracic and left lumbar regions). A left thoracic curvature should be suspected of being secondary to neurologic disease and prompt a more meticulous neurologic examination. If the curvatures of the spine are balanced (compensated), the head is centered over the center of the pelvis. If the spinal alignment is uncompensated, the head will be displaced to one side, which produces an unsightly deformity. Rotation of the spine may be measured with a scoliometer. Rotation is associated with a marked rib hump as the lateral curvature increases in severity.

imageTreatment

Treatment of scoliosis depends on the curve magnitude, skeletal maturity, and risk of progression. Treatment is indicated for any curvature that demonstrates progression on serial radiologic examination. Definitive spinal fusions should be delayed as long as possible in young children through the use of casting, bracing, and growth modulating surgeries such as growing rods or vertical expandable prosthetic titanium ribs (VEPTR).

Management of scoliosis is dependent on the Cobb angle, measured on standing anteroposterior x-rays of the spine. Curvatures of less than 20 degrees typically do not require treatment unless they show progression. Bracing is controversial, but often used for curvatures of 20–40 degrees in a skeletally immature child. Recent studies have shown bracing to be effective for female patients with a Cobb angle of 25–35 degrees. Bracing and casting may be a beneficial way to prevent the progression of scoliosis without the negative quality of life effects associated with other treatments. Curvatures greater than 40 degrees are resistant to treatment by bracing. Thoracic curvatures greater than 70 degrees have been correlated with poor pulmonary function in adult life, leading treatment algorithms toward preventing progression to this extreme. Curvatures reaching a magnitude of 40–60 degrees are indicated for surgical correction as they are highly likely to continue to progress, ultimately reaching the 70 degree threshold in adulthood. Surgical intervention should be geared to maximize pulmonary function, while improving spinal alignment.

The surgical procedure for scoliosis has two fundamental components: deformity correction and spinal fusion. Spinal instrumentation (rods, screws, hooks, etc) are applied to the region of the spine to be corrected. The instrumentation is then used to manually reposition the spine intraoperatively. Surgical fusion involves decortication of the bone over the laminas and spinous processes, with the addition of bone graft. The instrumentation is then secured/tightened in order to maintain postoperative correction, with activity restriction for several months until the bone fusion is solid. Treatment requires a team approach and is best done in centers with full support facilities.

imagePrognosis

Compensated small curves that do not progress may cause minor deformities but are well tolerated throughout life. Patients should be counseled about the genetic transmission of scoliosis and cautioned that their children’s backs should be examined as part of routine physicals. Early detection allows for simple brace treatment. Severe scoliosis may require correction by spinal fusion, although fusionless techniques are being developed.

Gummerson NW, Millner PA: Spinal fusion for scoliosis, clinical decision-making and choice of approach and devices. Skeletal Radiol 2010;39:939–942 [PMID: 20640417].

Maruyama T et al: Effectiveness and outcomes of brace treatment: a systematic review. Physiother Theory Pract 2011;21:26–42 [PMID: 21198404].

SLIPPED CAPITAL FEMORAL EPIPHYSIS

Slipped capital femoral epiphysis (SCFE) is caused by displacement of the proximal femoral epiphysis due to disruption of the growth plate. The head of the femur is usually displaced medially and posteriorly relative to the femoral neck. This condition is most commonly seen in adolescent, obese males. It occurs when stress increases across the proximal femoral physis (growth plate) or resistance to shear is reduced. Factors that can lead to this increase in stress or decrease in resistance include endocrine disorders, obesity, coxa profunda (a deep acetabular socket), and femoral or acetabular retroversion. Femoral version refers to the angle of inclination (anteversion) of the femoral neck towards the hip joint (femoral head) relative to the shaft of the femur. Retroversion of the femur occurs when the same proximal femoral segment is angled posteriorly relative to the shaft of the femur. Acetabular retroversion refers to when the alignment of the mouth of the acetabulum does not face the normal anterolateral direction, but inclines more posterolaterally. Experimental evidence has shown that the strength of the perichondrial ring stabilizing the epiphyseal area is sufficiently weakened by hormonal changes during adolescence such that the overload of excessive body weight can produce a pathologic fracture through the growth plate. Hormonal studies in affected children are usually normal, although SCFE is associated with hypothyroidism.

Clinically, SCFE is classified as stable or unstable. SCFE is considered stable if the child is able to bear weight on the affected extremity. In unstable SCFE, the child is unable to bear weight. An increased rate of avascular necrosis is correlated with the inability to bear weight.

Acute SCFE occasionally occurs following a fall or direct trauma to the hip. More commonly, vague symptoms occur over a protracted period in an otherwise healthy child who presents with pain and limp. The pain can be referred into the thigh or the medial side of the knee, making examination of the hip joint important in any obese child complaining of knee pain. Physical examination consistently reveals a limitation of internal rotation of the hip. The diagnosis may be clearly apparent only in the lateral radiographic view.

Initial management consists of making the patient non–weight-bearing on crutches and immediate referral to an orthopedic surgeon. Treatment is based on the same principles that govern treatment of any fracture of the femoral neck: the head of the femur is internally fixed to the neck of the femur and the fracture line allowed to heal.

The long-term prognosis is guarded because most of these patients continue to be overweight and overstress their hip joints. Follow-up studies have shown a high incidence of premature degenerative arthritis, even in those who do not develop avascular necrosis. The development of avascular necrosis almost guarantees a poor prognosis, because new bone does not readily replace the dead bone at this late stage of skeletal development. About 30% of patients have bilateral involvement, which may occur as late as 1 or 2 years after the primary episode.

Anderson LA, Kapron AL, Aoki SK, Peters CL: Coxa profunda: is the deep acetabulum overcovered? Clin Orthop Relat Res 2012;470(12):3375–3382 [PMID: 22898988].

Gholve PA, Cameron DB, Millis MB: Slipped capital femoral epiphysis update. Curr Opin Pediatr 2009;21(1):39–45 [PMID: 19242240].

Novais EN, Millis MB: Slipped capital femoral epiphysis: prevalence, pathogenesis, and natural history. Clin Orthop Relat Res 2012;470(12):3432–3438 [PMID: 23054509].

Reynolds D, Lucas J, Klaue K: Retroversion of the acetabulum: a cause of hip pain. J Bone Joint Surg Br 1999;81(2):281–288 [PMID: 10204935].

GENU VARUM & GENU VALGUM

Genu varum (bowleg) is normal from infancy through 3 years of age. The alignment then changes to genu valgum (knock-knee) until about age 8 years, at which time adult alignment is attained. If bowing persists beyond age 2, increases rather than decreases, occurs in only one leg, or if a patient is knock-kneed in association with short stature, the patient should be referred to an orthopedist. Genu varum is usually secondary to tibial rotation, while genu valgum may be caused by skeletal dysplasia or rickets.

Individuals with genu varum may be at a greater risk for falling as the deformity increases the normal postural sway in the mediolateral direction. Bracing may be appropriate. An osteotomy may be necessary for severe problems such as occurs in Blount disease (proximal tibial epiphysial dysplasia).

Fabry G: Clinical practice: static, axial, and rotational deformities of the lower extremities in children. Eur J Pediatr 2010;169(5):529–534 [PMID: 20052491].

Samaei A, Bakhtiary AH, Elham F, Rezasoltani A: Effects of genu varum deformity on postural stability. Int J Sports Med 2012;33(6):469–473 [PMID: 22377938].

TIBIAL TORSION

“Toeing in” in small children is a common parental concern. Tibial torsion refers to rotation of the leg between the knee and the ankle. Internal rotation amounts to about 20 degrees at birth but decreases to neutral rotation by age 16 months. The deformity may be accentuated by laxity of the knee ligaments, which allows excessive internal rotation of the leg in small children. This condition is largely self-limiting and usually resolves spontaneously with further growth and development. Treatment is focused on educating the families to the benign nature and expected resolution with observation.

FEMORAL ANTEVERSION

Toeing in beyond age 2 or 3 years is usually secondary to femoral anteversion, characterized by more internal rotation of the hip than external rotation. This femoral alignment decreases toward neutral during growth. Little is gained by active treatment with shoes or braces. Active external rotation exercises, such as skating or bicycle riding, are encouraged. Osteotomy for rotational correction is rarely required. Children who have no external rotation of the hip in extension are candidates for orthopedic consultation. However, the vast majority go on to resolve spontaneously.

Lincoln TL, Suen PW: Common rotational variations in children. J Am Acad Orthop Surg 2003;11:312 [PMID: 14565753].

COMMON FOOT PROBLEMS

When a child begins to stand and walk, the longitudinal arch of the foot is flat with a medial bulge over the inner border of the foot. The forefeet are mildly pronated or rotated inward, with a slight valgus alignment of the knees. As the child grows and joint laxity decreases, the long arch is better supported and more normal relationships occur in the lower extremities. (See also sections Metatarsus Varus and Clubfoot [Talipes Equinovarus].)

Flatfoot

Flatfoot is normal in infants. If the heel cord is of normal length, full dorsiflexion is possible when the heel is in the neutral position. As long as the heel cord is of normal length and a longitudinal arch is noted when the child is sitting in a non–weight-bearing position, a normal arch will generally develop.

Younger children who are male, obese, and have excessive joint laxity are more likely to be flatfooted. Around 15% of flatfeet do not resolve spontaneously. There is usually a familial incidence of relaxed flatfeet in children who have no apparent arch. In any child with a shortened heel cord or stiffness of the foot, other causes of flatfoot such as tarsal coalition (congenital fusion of the tarsal bones) should be ruled out by a complete orthopedic examination and radiographs.

For an ordinary relaxed flatfoot, no active treatment is indicated unless calf or leg pain is present. In children who have leg pains attributable to flatfoot, a supportive shoe, such as a good-quality sports shoe, is useful. An orthotic that holds the heel in neutral position and supports the arch may relieve discomfort if more support is needed. An arch insert should not be prescribed unless passive correction of the arch is easily accomplished; otherwise, the skin over the medial side of the foot will be irritated.

Chen KC, Tunk LK, Yeh CJ, Yang JF, Kuo JF, Wang CH: Change in flatfoot of preschool-aged children: a 1-year follow-up study. Eur J Pediatr 2013;172(2):255–260 [PMID: 23132641].

Fabry G: Clinical practice: Static, axial, and rotational deformities of the lower extremities in children. Eur J Pediatr 2010;169(5):529–534 [PMID: 20052491].

Talipes Calcaneovalgus

Talipes calcaneovalgus is characterized by excessive dorsiflexion at the ankle and eversion of the foot. This disorder can be associated with posteromedial bowing of the tibia and is due to intrauterine position and is often present at birth. The deformity occurs in 0.4-1–0 per 1000 live births. Treatment consists of passive exercises, such as stretching the foot into plantar flexion. With or without treatment, the deformity usually resolves by age 3–6 months. In rare instances, it may be necessary to use plaster casts to help with manipulation and positioning. Complete correction is the rule.

Sankar WN, Weiss J, Skaggs DL: Orthopedic conditions in the newborn. J Am Acad Orthop Surg 2009;17(2):112–122 [PMID: 19202124].

Cavus Foot

Cavus foot consists of an unusually high longitudinal arch of the foot. It may be hereditary or associated with neurologic conditions such as poliomyelitis, hereditary sensory motor neuropathies, and diastematomyelia (congenital splitting of the spinal cord). Typically there is an associated contracture of the toe extensors, producing a claw toe deformity in which the metatarsal phalangeal joints are hyperextended and the interphalangeal joints acutely flexed. Cavus foot presents with diffuse and localized pain in the lower legs and is commonly associated with an inflexible foot deformity. Any child presenting with cavus feet should receive a careful neurologic examination as well as radiographs and magnetic resonance imaging (MRI) of the spine.

Conservative therapy, such as an orthotic to realign the foot, can be effective in milder cases. In symptomatic cases, surgery may be necessary to lengthen the contracted extensor and flexor tendons and to release the plantar fascia and other tight plantar structures. Associated varus heel deformities cause more problems than the high arch.

Fabry G: Clinical practice: Static axial and rotational deformities of the lower extremities in children. Eur J Pediatr 2010; 169(5):529–534 [PMID: 20052491].

Wicart P: Cavus foot, from neonates to adolescents. Orthop Traumatol Surg Res 2012;98(7):813–828 [PMID: 23098772].

Bunions (Hallux Valgus)

With a prevalence of 23%–35%, hallux valgus is the most common forefoot deformity. The etiology is unknown. Adolescents may present with lateral deviation of the great toe associated with a prominence over the head of the first metatarsal. Around 60% of patients have a family history of this condition. The deformity is painful with shoe wear and almost always relieved by fitting shoes that are wide enough in the toe area. Since further growth tends to cause recurrence of the deformity, surgery should be avoided in the adolescent.

Therapeutic treatments are aimed at correcting the muscular and weight bearing forces that act on the joint. While conservative treatment provides symptomatic relief, it does not reverse the natural history, as these deformities will typically continue to progress until corrected surgically. A high percentage of these patients ultimately have surgery in adulthood due to a continued progression of the deformity. Proper surgical treatment results in a very good, good, or satisfactory outcome in 95% of patients.

Glasoe WM, Nuckley DJ, Ludewig PM: Hallux valgus and the first metatarsal arch segment: a theoretical biomechanical perspective. Phys Ther 2010;90:110–120 [PMID: 19926679].

Wulker N, Mittag F: The treatment of hallux valgus. Dtsch Arztbebl Int 2012;109(49):857–868 [PMID: 23267411].

DEGENERATIVE PROBLEMS (ARTHRITIS, BURSITIS, & TENOSYNOVITIS)

image ESSENTIALS OF DIAGNOSIS & TREATMENT

image Chronic conditions.

image Overuse syndromes.

image Rule out more serious conditions first.

image Activity restriction is the treatment.

Degenerative arthritis may follow childhood skeletal problems, such as infection, SCFE, avascular necrosis, trauma, or hemarthroses in patients with hemophilia. Early, effective treatment of these disorders can prevent arthritis. Overuse in young athletes can also cause degenerative changes to the soft tissues around the joints. Young boys throwing excessive numbers of pitches, especially curve balls, may develop “Little League” elbow, consisting of degenerative changes around the humeral condyles associated with pain, swelling, and limitation of motion (see Chapter 27). Limitation of the number of pitches thrown by little league pitchers is the key to prevention.

Acute bursitis is uncommon in childhood, and other causes should be ruled out before this diagnosis is accepted.

Tenosynovitis is most common in the knees and feet. Children taking dancing lessons, particularly toe dancing, may have pain around the flexor tendon sheaths in the toes or ankles. Rest is effective treatment. Around the knee, the patellar ligament may be irritated, with associated swelling in the infrapatellar fat pad. Synovitis in this area is usually due to overuse and is treated by rest and nonsteroidal anti-inflammatory drugs. Corticosteroid injections are contraindicated.

TRAUMA

image ESSENTIALS OF DIAGNOSIS & TREATMENT

image Directed physical examination (eg, swelling, tenderness, deformity, instability).

image Radiographic examination.

image Rule out physeal fracture.

image Early motion for sprains and strains.

image Reduction and immobilization for fractures.

SOFT TISSUE TRAUMA (SPRAINS, STRAINS, & CONTUSIONS)

A sprain is the stretching of a ligament and a strain is a stretch of a muscle or tendon. Contusions are generally due to tissue compression, with damage to blood vessels within the tissue and the formation of a hematoma.

In a severe sprain, the ligament is completely disrupted resulting in instability of the joint. Incomplete tearing of the ligament, with local pain and swelling but no joint instability, is considered a mild or moderate sprain.

The initial treatment of any sprain consists of ice, compression, and elevation. Brief splinting followed by early range of motion exercises of the affected joint protect against further injury and relieves swelling and pain. Ibuprofen and other nonsteroidal anti-inflammatory drugs are useful for pain. Rest, ice, and elevation are usually sufficient for mild or moderate sprains. If more severe trauma occurs, resulting in complete tearing of a ligament, instability of the joint may be demonstrated by gross examination or by stress testing with radiographic documentation. Such deformity of the joint may cause persistent instability resulting from inaccurate apposition of the ligament ends during healing. If instability is evident, surgical repair of the torn ligament may be indicated. If a muscle is torn at its tendinous insertion, it also should be repaired surgically.

Ankle Sprains

The history will indicate that the injury was by either forceful inversion or eversion. The more common inversion injury results in tearing or injury to the lateral ligaments, whereas an eversion injury will injure the medial ligaments of the ankle. The injured ligaments can be identified by careful palpation for point tenderness around the ankle. The joint should be supported or immobilized in the functional position (right angle). Use of an air splint produces joint rest, and the extremity can be protected by using crutches. Functional rehabilitation to include edema control, range of motion, strengthening, and restoration of proprioceptive sensation can prevent long-term disability. Re-injury is common. Continued injury can lead to chronic ankle instability.

Kemler E, Port I, Backx F, Dijk CN: A systematic review on the treatment of acute ankle sprain brace versus other functional treatment types. Sports Med 2011;41:185–197 [PMID: 21395362].

Knee Sprains

Sprains of the collateral and cruciate ligaments are uncommon in children. These ligaments are so strong that it is more common to injure the growth plates, which are the weakest structures in the region of the knees of children. In adolescence, as the physes start to close, rupture of the anterior cruciate ligament can result from a rotational injury. If the injury produces avulsion of the tibial spine, anatomic reduction and fixation are often required.

Effusion of the knee after trauma deserves referral to an orthopedic specialist. The differential diagnosis includes torn ligament, torn meniscus, and osteochondral fracture. Nontraumatic effusion should be evaluated for inflammatory conditions (eg, juvenile rheumatoid arthritis) or patellar malalignment.

Vaquero J, Vidal C, Cubillo A: Intra-articular traumatic disorders of the knee in children and adolescents. Clin Orthop Relat Res 2005;432:97 [Review] [PMID: 15738809].

Internal Derangements of the Knee

Meniscal injuries are uncommon in children younger than 12 years of age. Clicking or locking of the knee may occur in young children as a result of a discoid lateral meniscus, which is a rare congenital anomaly. As the child approaches adolescence, internal damage to the knee from a torsion weight-bearing injury may result in locking of the knee if tearing and displacement of a meniscus occurs. Osteochondritis dissecans also presents as swelling and mechanical symptoms of the knee in adolescence. Posttraumatic synovitis may mimic a meniscal lesion. Epiphysial injury should be suspected in any severe injury to the knee or when there is tenderness on both sides of the femoral metaphysis after injury. Stress films will sometimes demonstrate separation of the distal femoral epiphysis.

Kapur S et al: Acute knee dislocation review of an elusive entity. Curr Probl Diagn Radiol 2009;38(6):237–250 [PMID: 19778658].

Back Sprains

Sprains of the ligaments and muscles of the back are unusual in children but may occur as a result of violent trauma from automobile accidents or athletic injuries. Sprains usually cause lateral and midline pain over musculature. Back pain in a child may be the only symptom of significant disease and warrants clinical investigation. Inflammation, infection, renal disease, or tumors can cause back pain in children, and sprain should not be accepted as a routine diagnosis.

Gurd DP: Back pain in the young athlete. Sports Med Arthrosc Rev 2011;19:7–16 [PMID: 21293233].

Contusions

Muscle contusions with hematoma formation produce the familiar “charley horse” injury. Treatment includes application of ice, compression, and rest. Exercise should be avoided for 5–7 days. Local heat may hasten healing once the acute phase of tenderness and swelling has passed.

Myositis Ossificans

Ossification within muscle occurs when sufficient trauma causes a hematoma that later heals in the manner of a fracture. Contusions of the quadriceps of the thigh or the triceps of the arm are the most common injuries.

Disability is great, with local swelling, heat and extreme pain with the slightest provocation of the adjacent joint. The limb should be rested until the local reaction has subsided (5–7 days). When local heat and tenderness have decreased, gentle active exercises may be initiated. Passive stretching exercises are not indicated as they may stimulate the ossification reaction. If an extremity experiences a severe injury with a hematoma, it should be splinted and further activity should be avoided until the acute reaction has subsided. If additional trauma causes recurrent injury, ossification may reach spectacular proportions and resemble an osteosarcoma. Surgery to excise the ossification may restart the process and lead to an even more severe reaction and should not be attempted before 9 months to 1 year after injury.

TRAUMATIC SUBLUXATIONS & DISLOCATIONS

Joint dislocation is always associated with severe damage to the joint capsule and associated ligaments. In contrast to fracture reduction, which may be safely postponed, dislocations must be reduced immediately in order to minimize further joint damage. Dislocations can usually be reduced by gentle sustained traction. Often, no anesthetic is needed for several hours after the injury due to the protective anesthesia produced by the injury. A thorough neurovascular examination should be performed and documented pre- and postreduction. Radiographs should be obtained postreduction to document congruency and assess for the presence of associated fractures. Following reduction, the joint should be splinted for transportation of the patient.

The dislocated joint should be treated by immobilization, followed by graduated active exercises through a full range of motion. Vigorous passive manipulation of the joint by a therapist may be harmful.

Subluxation of the Radial Head (Nursemaid’s Elbow)

Infants may sustain subluxation of the radial head as a result of being lifted or pulled by the hand. The child appears with the elbow fully pronated and painful. The usual complaint is that the child’s elbow will not bend. Radiographic findings are normal, but there is point tenderness over the radial head. When the elbow is placed in full supination and slowly moved from full extension to full flexion, a click may be palpated at the level of the radial head. The relief of pain is remarkable, as the child usually stops crying immediately. The elbow may be immobilized in a sling for comfort for a day. Occasionally, symptoms last for several days, requiring more prolonged immobilization.

A pulled elbow may be a clue to battering. This should be considered during examination, especially if the problem is recurrent.

Dislocation of the Patella

Complete patellar dislocations nearly always dislocate laterally. Pain is severe, and the patient will present with the knee slightly flexed and an obvious bony mass lateral to the knee joint associated with a flat area over the anterior knee. Radiologic examination confirms the diagnosis. The patella may be reduced by extending the knee and placing slight pressure on the patella while gentle traction is exerted on the leg. When subluxation of the patella occurs, symptoms may be more subtle, and the patient will complain that the knee “gives out” or “jumps out of place.”

Recurrent dislocations more commonly occur in loose-jointed individuals, especially adolescent girls. Factors that affect risk for recurrence include length of patellar tendon, the depth of trochlear groove, and position of the patella in relation to the trochlear groove.

For first-time dislocation, initial treatment after reduction should be nonoperative, consisting of physical therapy to strengthen the quadriceps, hips, and core stabilizers. Surgery is reserved for individuals with reparable osteochondral injuries, loose bodies, and recurrent dislocation following appropriate nonoperative therapy. Around one-third of patients report a repeated dislocation after rehabilitation.

Kapur S et al: Acute knee dislocation review of an elusive entity. Curr Probl Diagn Radiol 2009;38(6):237–250 [PMID: 19778658].

Petri M et al: Operative vs conservative treatment of traumatic patellar dislocation: results of a prospective randomized controlled clinical trial. Arch Orthop Trauma Surg 2013;133(2):209–213 [PMID: 23138693].

Smith TO et al: Clinical outcomes of rehabilitation for patients following lateral patellar dislocation. Physiotherapy 2010;96: 269–281 [PMID: 21056161].

FRACTURES

Epiphyseal Separations

Epiphyseal separations (also referred to as epiphyseal fractures) are more common than ligamentous injuries in children since the ligaments of the joints are generally stronger than their associated growth plates. Radiographs should be taken whenever a dislocation is suspected in order to rule out epiphyseal fracture. Radiographs of the opposite extremity, especially for injuries around the elbow, are valuable for comparison. Fractures across the growth plate may produce bony bridges that will cause premature cessation of growth or angular deformities of the extremity. These bridges are due to trauma to the growth plate and can occur even with adequate reductions.

Reduction of a fractured epiphysis should be done under anesthesia to align the growth plate with the least amount of force. Epiphyseal fractures around the shoulder, wrist, and fingers can usually be treated by closed reduction, but fractures of the epiphyses around the elbow often require open reduction. In the lower extremity, accurate reduction of the epiphyseal plate is necessary to prevent joint deformity when a joint surface is involved. If angular deformities result, corrective osteotomy may be necessary.

Dwek JR: The radiographic approach to child abuse. Clin Orthop Relat Res 2011;469:776–789 [PMID: 20544318].

Torus Fractures

Torus fractures consist of “buckling” of the cortex due to compression of the bone. They are most common in the distal radius or ulna. Alignment is usually satisfactory, and simple immobilization for 3 weeks is sufficient. Soft bandage therapy and cast therapy are effective in preventing further angulation. It is important that the fracture is not misdiagnosed as a greenstick fracture (see below) at initial presentation. Children with a torus fracture who are misdiagnosed with a greenstick fracture report having more pain after application of a soft bandage or cast.

Vernooij CM, Vreeburg ME, Segers MJ, Hammacher ER: Treatment of torus fractures in the forearm in children using bandage therapy. J Trauma Acute Care Surg 2012;72(4): 1093–1097 [PMID: 22491633].

Greenstick Fractures

Greenstick fractures involve frank disruption of the cortex on one side of the bone but no discernible cleavage plane on the opposite side. The term “greenstick” implies similarity to what happens when one tries to break a twig/stick from a live tree; commonly bark will break on one side of the stick, while remaining intact on the opposite side. Bone ends are not separated, making these fractures angulated but not displaced. Reduction is achieved by straightening the arm into normal alignment and maintaining alignment with a snugly fitting cast. It is necessary to obtain radiographs of greenstick fractures again in 7–10 days to make certain that the reduction has been maintained in the cast. A slight angular deformity can be corrected by remodeling of the bone. The farther the fracture is from the growing end of the bone, the longer the time required for remodeling. The fracture can be considered healed when no tenderness is present and a bony callus is seen on a radiograph.

Fracture of the Clavicle

Clavicular fractures are very common injuries in infants and children. The patient can be immobilized in a sling for comfort. The healing callus will be apparent when the fracture has consolidated, but this unsightly lump will generally resolve over a period of months to a year via bone remodeling.

Supracondylar Fractures of the Humerus

The condyles of the distal humerus form the proximal half of the elbow joint. There is a concavity in the posterior distal humerus that is present anatomically to accommodate the olecranon when the elbow reaches full extension. This anatomic accommodation, located in what is referred to as the supracondylar region of the humerus, also creates a thinner area of cortical bone that is more susceptible to injury/fracture. Supracondylar fractures tend to occur in children age 3–6 years and are the most common elbow fracture in children. The proximity to the brachial artery in the distal arm creates a potential danger when dealing with these types of fractures. Absence of a distal pulse is a strong indicator of a secondary arterial injury. Swelling may be severe as these injuries are usually associated with a significant amount of trauma. Most often, these fractures are treated by closed reduction and percutaneous pinning performed under general anesthesia. Complications associated with supracondylar fractures include Volkmann ischemic contracture of the forearm due to vascular compromise and cubitus varus (decreased carrying angle, “gunstock deformity”) secondary to poor reduction. The “gunstock deformity” of the elbow may be somewhat unsightly but does not usually interfere with joint function.

White L: A systematic review of vascular injuries in pediatric supracondylar humerus fractures and results of a POSNA questionnaire. J Pediatr Orthop 2010;30:328–335 [PMID: 20502231].

General Comments on Other Fractures in Children

Reduction of fractures in children can usually be accomplished by simple traction and manipulation; open reduction is indicated if a satisfactory alignment is not obtained. Remodeling of the fracture callus generally produces an almost normal appearance of the bone over a matter of months. The younger the child, the more remodeling is possible. Angular deformities in the plane of joint motion remodel reliably while rotational malalignment does not remodel well.

There should be suspicion of child abuse whenever the age of a fracture does not match the history given or when the severity of the injury is more than the alleged accident would have produced. In suspected cases of battering in which no fracture is present on the initial radiograph, a repeat radiograph 10 days later is in order. Bleeding beneath the periosteum will be calcified by 7–10 days, and the radiographic appearance can be diagnostic of severe closed trauma characteristic of a battered child.

INFECTIONS OF THE BONES & JOINTS

image ESSENTIALS OF DIAGNOSIS & TREATMENT

image Movement of the extremity causes pain.

image Soft tissue swelling.

image Elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP).

image Surgical drainage of abscess, plus antibiotics.

image Antibiotic therapy for early osteomyelitis without abscess.

OSTEOMYELITIS

Osteomyelitis is an infectious process that usually starts in the spongy or medullary bone and extends into compact or cortical bone. Commonly preceded by trauma, the lower extremities are more likely to be affected. Osteomyelitis is most commonly caused by hematogenous spread of bacteria from other infected or colonized areas (eg, pyoderma or upper respiratory tract) but it may occur as a result of direct invasion from the outside (exogenous), through a penetrating wound (nail) or open fracture. Staphylococcus aureus is the most common infecting organism and has a tendency to infect the metaphyses of growing bones. Anatomically, the arterial supply to the metaphysis in the long bones includes end arteries just below the growth plate which turn sharply and end in venous sinusoids, causing relative stasis that predisposes to bacterial localization. In the infant (younger than age 1 year), there is direct vascular communication with the epiphysis across the growth plate. Bacterial spread occurs from the metaphysis to the epiphysis and into the joint. In the older child, the growth plate provides an effective barrier and the epiphysis is usually not infected. Infection spreads retrograde from the metaphysis into the diaphysis, and by rupture through the cortical bone, down along the diaphysis beneath the periosteum.

Exogenous Osteomyelitis

All wounds must be carefully examined and cleansed to avoid osteomyelitis by direct extension. Osteomyelitis is a common occurrence from pressure sores in insensate areas, such as in patients with spina bifida. Copious irrigation is necessary, and all nonviable skin, subcutaneous tissue, fascia, and muscle must be excised. In extensive or contaminated wounds, antibiotic coverage is indicated. Contaminated lacerations should be left open and secondary closure performed 3–5 days later. Leaving the wound open allows infection to stay at the surface rather than extend inward to the bone. Further necrotic tissue should be excised if present at the time of delayed closure. Puncture wounds are especially prone to causing osteomyelitis and should be carefully debrided.

Initially, broad-spectrum antibiotics should be administered for contaminated wounds, but the final choice of antibiotics is directed by culture results. A tetanus toxoid booster may be indicated. Gas gangrene is best prevented by adequate debridement.

After exogenous osteomyelitis has become established, treatment becomes more complicated, requiring extensive surgical debridement and antibiotics, initially by the intravenous route. Definitive antibiotic selection should generally be guided by bacterial cultures of infected bone.

Hematogenous Osteomyelitis

Hematogenous osteomyelitis is the most common infection of the bone in children. It most often occurs in the metaphyseal region of tubular bones and is usually caused by pyogenic bacteria; 85% of cases are due to staphylococci. Streptococci (group B Streptococcus in young infants, Streptococcus pyogenes in older children) are a less common cause of osteomyelitis. Pseudomonas aeruginosa is common in cases of nail puncture wounds. Children with sickle cell anemia are especially prone to osteomyelitis caused by Salmonella spp.

imageClinical Findings

A. Symptoms and Signs

Osteomyelitis may be subtle in infants, presenting as irritability, diarrhea, or failure to feed properly; temperature may be normal or slightly low; and white blood cell count may be normal or only slightly elevated. There may be pseudoparalysis of the involved limb. Manifestations are more striking in older children, with severe local tenderness and pain and, often, but not invariably, high fever, rapid pulse, and elevated white blood cell count, ESR, and CRP. Osteomyelitis of a lower extremity often occurs around the knee joint in children age 7–10 years. Tenderness is most marked over the metaphysis of the bone where the process has its origin. For a child who refuses to bear weight, osteomyelitis is high in the differential diagnosis.

B. Laboratory Findings

Blood cultures are often positive early. The most important test is the aspiration of pus or biopsy of involved bone. It is useful to insert a needle into the bone in the area of suspected infection and aspirate any fluid present. Fluid should be stained for organisms and cultured. Even edema fluid can be useful for determining the causative organism. Elevation of the ESR above 50 mm/h is typical for osteomyelitis. CRP is elevated earlier than the ESR.

C. Imaging

Osteomyelitis should be diagnosed clinically before significant plain radiographic findings are present. Plain film findings progress from nonspecific local swelling, to elevation of the periosteum, with formation of new bone from the cambium layer of the periosteum occurring after 3–6 days. As infection becomes chronic, areas of cortical bone are isolated by pus spreading down the medullary canal, causing rarefaction and demineralization of the bone. Isolated pieces of cortex become ischemic and form sequestra (dead bone fragments). These radiographic findings are specific, but late. Bone scan is sensitive (before plain radiographic findings are apparent) but nonspecific and should be interpreted in the clinical context. MRI can demonstrate early edema and subperiosteal abscess and is helpful to confirm and localize disease prior to plain film changes.

imageTreatment

A. Specific Measures

Intravenous antibiotics should be started as soon as the diagnosis of osteomyelitis is made and diagnostic specimens have been obtained. Transition to oral antibiotics occurs when tenderness, fever, the white cell count, and the CRP are all resolved/decreasing and is facilitated by a positive culture. Agents that cover S aureus and Streptococcus pyogenes (eg, oxacillin, nafcillin, cefazolin, and clindamycin) are appropriate for most cases. Alternative antistaphylococcal therapy (eg, vancomycin) may be needed if methicillin-resistant and clindamycin-resistant S. aureus is suspected or isolated. Methicillin-resistant S aureus infection should be suspected in patients with severe cases of hematogenous osteomyelitis. Consultation with an infectious disease specialist can be helpful. For specific recommendations and for possible Pseudomonas infection, see Chapter 42.

Acute osteomyelitis is usually treated for a minimum of 4–6 weeks and until normalization of the physical exam and inflammatory markers. Chronic infections are treated for months. Following surgical debridement, Pseudomonas foot infections usually respond to 1–2 weeks of antibiotic treatment.

B. General Measures

Splinting minimizes pain and decreases spread of the infection through lymphatic channels in the soft tissue. The splint should be removed periodically to allow active use of adjacent joints and prevent stiffening and muscle atrophy. In chronic osteomyelitis, splinting may be necessary to guard against fracture of the weakened bone.

C. Surgical Measures

Aspiration of the metaphysis for culture and Gram stain is the most useful diagnostic measure in any case of suspected osteomyelitis. If frank pus is aspirated from the bone, surgical drainage is indicated. If the infection has not shown a significant response within 24 hours, surgical drainage is also indicated. It is important that all devitalized soft tissue be removed and adequate exposure of the bone be obtained to permit free drainage. Excessive amounts of bone should not be removed when draining acute osteomyelitis as it will not be completely replaced by the normal healing process. Bone damage is limited by surgical drainage, whereas failure to evacuate pus in acute cases may lead to widespread damage.

imagePrognosis

When osteomyelitis is diagnosed in the early clinical stages and prompt antibiotic therapy is begun, the prognosis is excellent. If the process has been unattended for a week to 10 days, there is almost always some permanent loss of bone structure, as well as the possibility of future growth abnormality due to physeal injury.

Bouchoucha S et al: Epidemiology of acute hematogenous osteomyelitis in children: a prospective study over a 32 months period. Tunis Med 2012;90(6):473–480 [PMID: 22693089].

Conrad DA: Acute hematogenous osteomyelitis. Am Acad Pediatr 2011;31:464–471 [PMID: 21041424].

Harik NS, Smeltzer MS: Management of acute hematogenous osteomyelitis in children. Expert Rev Anti Infect Ther 2010;8(2):175–181 [PMID: 20109047].

imagePyogenic Arthritis

The source of pyogenic arthritis varies according to the child’s age. Infantile pyogenic arthritis often develops from adjacent osteomyelitis. In older children, it presents as an isolated infection, usually without bony involvement. In teenagers with pyogenic arthritis, an underlying systemic disease or an organism that has an affinity for joints (eg, Neisseria gonorrhoeae) may be present.

The most frequent infecting organisms similarly vary with age: group B Streptococcus and S aureus in those younger than age 4 months; Haemophilus influenzae B (if unimmunized) and S aureus in those aged 4 months to 4 years; and S aureus and S pyogenes in older children and adolescents. Streptococcus pneumoniae and Neisseria meningitis are occasionally implicated, and Neisseria gonorrhoeae is a cause in adolescents. H influenzae B is now uncommon in the United States because of effective immunization. Kingella kingae is a gram-negative bacterium that is increasingly recognized as a cause of pyarthrosis in children less than 5 years of age.

The initial effusion of the joint rapidly becomes purulent in pyogenic arthritis. A joint effusion may accompany osteomyelitis in the adjacent bone, but a white cell count exceeding 50,000/μL in the joint fluid indicates a purulent infection involving the joint. Generally, spread of infection is from bone into a joint, but unattended pyogenic arthritis may also affect adjacent bone. The ESR is often above 50 mm/h.

imageClinical Findings

A. Symptoms and Signs

In older children, signs may be striking, with fever, malaise, vomiting, and restriction of motion. In infants, paralysis of the limb due to inflammatory pseudoparalysis may be evident. Infection of the hip joint in infants should be suspected if decreased abduction of the hip is present in an infant who is irritable or feeding poorly. A history of umbilical catheter treatment in the newborn nursery should alert the physician to the possibility of pyogenic arthritis of the hip.

B. Imaging

Early distention of the joint capsule is nonspecific and difficult to measure by plain radiograph. In infants with unrecognized pyogenic arthritis, dislocation of the joint may follow within a few days as a result of distention of the capsule by pus. Destruction of the joint space, resorption of epiphysial cartilage, and erosion of the adjacent bone of the metaphysis occur later. The bone scan shows increased flow and increased uptake about the joint. MRI and ultrasound imaging are useful adjuncts for detecting joint effusions, which can be helpful in assessing potential joint sepsis.

imageTreatment

Aspiration of the joint is the key to diagnosis. Surgical drainage followed by the appropriate antibiotic therapy provides the best treatment for pyogenic arthritis. Antibiotics can be selected based on the child’s age and results of the Gram stain and culture of aspirated pus. Reasonable empiric therapy in infants and young children is nafcillin or oxacillin plus a third-generation cephalosporin. An antistaphylococcal agent alone is usually adequate for children older than age 5 years, unless gonococcal or meningococcal infection is suspected. Alternative antistaphylococcal therapy (eg, clindamycin or vancomycin) may be needed if methicillin-resistant S aureus is suspected or isolated. Consultation with an infectious disease specialist can be helpful.

For staphylococcal infections, a minimum of 3 weeks of therapy and until examination and inflammatory markers are normal is recommended; for other organisms, a minimum of 2 weeks and until examination and inflammatory markers are normal is usually sufficient. Oral therapy may be begun when clinical signs and inflammatory markers have improved markedly. It is not necessary to give intra-articular antibiotics since good levels are achieved in the synovial fluid with parenteral administration.

imagePrognosis

The prognosis for the patient with pyogenic arthritis is excellent if the joint is drained before damage to the articular cartilage has occurred. If infection is present for more than 24 hours, dissolution of the proteoglycans in the articular cartilage takes place, with subsequent arthrosis and fibrosis of the joint. Damage to the growth plate may occur, especially within the hip joint, where the epiphyseal plate is intracapsular.

Jesus AA et al: Pediatric hereditary autoinflammatory syndromes. Jornal de Pediatria 2010;86(5):353–366 [PMID: 20938587].

Kim EY, Kwack KS, Cho JH, Lee DH, Yoon SH: Usefulness of dynamic contrast-enhanced MRI in differentiating between septic arthritis and transient synovitis in the hip joint. AJR Am J Roentgenol 2012;198(2):428–433 [PMID: 22268189].

TUBERCULOUS ARTHRITIS

Tuberculous arthritis is now a rare disease in the United States, afflicting children in poor social circumstances, such as homeless families, or children who have immigrated from tuberculosis-endemic regions or who are in contact with adults with tuberculosis risk factors. Generally, the infection may be ruled out by negative skin testing. The intervertebral discs are the most commonly affected sites of involvement in children, resulting in gibbus or dorsal angular deformity at the affected site. MRI is effective in showing the number of lesions, their location and size and whether or not necrosis has occurred.

Treatment is by local drainage of the abscess, followed by antituberculous therapy. Prolonged immobilization in a plaster cast or prolonged bed rest is necessary to promote healing. Spinal fusion may be required to preserve stability of the vertebral column.

Lu M: Imaging diagnosis of spinal intramedullary tuberculoma: Case reports and literature review. American Paraplegia Society. J Spinal Cord Med 2010;33(2):159-162. Review [PMID: 20486535].

DISKITIS

Diskitis is pyogenic infectious spondylitis in children. Although many infections are culture-negative, S aureus is considered to be the most frequent etiologic pathogen. The typical clinical presentation includes back pain and malaise over a several weeks to months duration. Younger children, less than 5 years, may not be able to localize their complaints and commonly present with “abdominal” pain. Supportive treatment and appropriate antibiotics are likely to lead to rapid relief of symptoms and signs without recurrence.

Gouliouris T, Aliyu SH, Brown NM: Spondylodiscitis update on diagnosis and management. Journal of Antimicrobial Chemotherapy 2010;65:11–24 [PMID: 20876624].

TRANSIENT (TOXIC) SYNOVITIS & SEPTIC ARTHRITIS OF THE HIP

The most common cause of limping and hip pain in children in the United States is transient synovitis. This acute inflammatory reaction often follows an upper respiratory or gastrointestinal infection and is generally self-limited. Classically affecting children aged 3–10 years, it is more common in boys than girls. The hip joint experiences limitation of motion, particularly internal rotation, and radiographic changes are nonspecific, with some swelling apparent in the soft tissues around the joint.

It is important for the provider to differentiate between transient synovitis and septic arthritis upon initial presentation. Early in the disease both conditions have similar symptoms but each requires a different treatment plan. Generally, toxic synovitis of the hip is not associated with elevation of the ESR, white blood cell count, or temperature above 38.3°C. In questionable cases, aspiration of the hip yields only yellowish fluid in transient synovitis rather than purulent fluid in pyogenic arthritis. Transient synovitis can be distinguished from septic arthritis with a dynamic contrast enhanced MRI (DCE-MRI).

Rest and nonsteroidal anti-inflammatory medications are the preferred treatments for transient synovitis, whereas patients afflicted with septic arthritis of the hip are treated with operative drainage followed by antibiotic treatment. Nonsteroidal anti-inflammatory drugs shorten the course of the transient synovitis, although even with no treatment, the disease usually runs its course in days. Radiographic follow-up is essential as toxic synovitis may be the precursor of avascular necrosis of the femoral head (described in the next section) in a small percentage of patients. Radiographs can be obtained at 6 weeks, or earlier if either a persistent limp or pain is present.

Fabry G: The hip from birth to adolescence. Eur J Pediatr 2010;169:143–148 [PMID: 19727813].

Kim EY, Kwack KS, Cho JH, Lee DH, Yoon SH: Usefulness of dynamic contrast-enhanced MRI in differentiating between septic arthritis and transient synovitis in the hip joint. AJR Am J Roentgenol 2012;198(2):428–433 [PMID: 22268189].

VASCULAR LESIONS & AVASCULAR NECROSIS (OSTEOCHONDROSES)

image ESSENTIALS OF DIAGNOSIS & TREATMENT

image Diagnosis made by characteristic radiographic findings.

image Radiographic resolution lags behind symptomatic resolution.

image Treatment for most cases is supportive.

Osteochondrosis (degeneration of an ossification center) due to vascular lesions may affect various growth centers. Table 26–1 indicates the common sites and the typical ages at presentation.

Table 26–1. The osteochondroses.

image

In contrast to other body tissues that undergo infarction, bone removes necrotic tissue and replaces it with living bone through creeping substitution (a process where necrotic bone is replaced by viable bone). This replacement of necrotic bone may be so complete that a normal bone results. Adequacy of replacement depends on the patient’s age, the presence or absence of associated infection, the congruity of the involved joint, and other physiologic and mechanical factors.

Rapid growth of the secondary ossification centers in the epiphyses in relation to their blood supply subject them to avascular necrosis. Despite the number of different names referring to avascular necrosis of the epiphyses (see Table 26–1), the process is identical: necrosis of bone followed by replacement.

Even though the pathologic and radiographic features of avascular necrosis of the epiphyses are well known, the cause is not generally agreed upon. Necrosis may follow known causes such as trauma or infection, but idiopathic lesions usually develop during periods of rapid growth of the epiphyses.

AVASCULAR NECROSIS OF THE PROXIMAL FEMUR (LEGG-CALVÉ-PERTHES DISEASE)

Necrosis results if the vascular supply to the proximal femur is interrupted.

imageClinical Findings

A. Symptoms and Signs

The highest incidence of Legg-Calvé-Perthes disease occurs between 4 and 8 years of age. Persistent pain is the most common symptom, and the patient may present with limp or limitation of motion.

B. Laboratory Findings

Laboratory findings, including studies of joint aspirates, are normal.

C. Imaging

Radiographic findings correlate with progression of the disease and the extent of necrosis. Effusion of the joint associated with slight widening of the joint space and periarticular swelling are the early findings. Decreased bone density in and around the joint is apparent after a few weeks. The necrotic ossification center appears denser than the surrounding viable structures, and the femoral head is collapsed or narrowed.

As replacement of the necrotic ossification center occurs, rarefaction of the bone begins in a patchwork fashion, producing alternating areas of rarefaction and relative density, referred to as “fragmentation” of the epiphysis.

Widening of the femoral head may be associated with flattening, or coxa plana. If infarction has extended across the growth plate, a radiolucent lesion will be evident within the metaphysis. If the growth center of the femoral head has been damaged and normal growth arrested, shortening of the femoral neck results.

Eventually, complete replacement of the epiphysis develops as living bone replaces necrotic bone by creeping substitution. The final shape of the head depends on the extent of the necrosis and collapse of weakened bone.

imageDifferential Diagnosis

Differential diagnosis includes inflammation and infection and dysplasia. Transient synovitis of the hip may be distinguished from Legg-Calvé-Perthes disease by serial radiographs.

imageTreatment

Protection of the joint by minimizing impact is the principal treatment. If the joint is deeply seated within the acetabulum and normal joint motion is maintained, a reasonably good hip can result. Little benefit has been shown from bracing. Surgical treatment is controversial.

imagePrognosis

The prognosis for complete replacement of the necrotic femoral head in a child is excellent, but the functional result depends on the amount of deformity that has developed. Better outcomes are observed for patients with an onset of symptoms before the age of 6. Generally a poorer prognosis is expected for patients who develop the disease late in childhood, those with more completed involvement of the epiphysial center, those with metaphysial defects and those who have more complete involvement of the femoral head.

Kim HW, Herring JA: Pathophysiology, classifications, and natural history of perthes disease. Orthop Clin N Am 2011;42: 285–295 [PMID: 21742140].

OSTEOCHONDRITIS DISSECANS

In osteochondritis dissecans, a wedge-shaped necrotic area of bone and cartilage develops adjacent to the articular surface. The fragment of bone may break off from the host bone and displace into the joint as a loose body. If it remains attached, the necrotic fragment may be completely replaced through creeping substitution.

The pathologic process is the same as that for avascular necrosing lesions of ossification centers. Joint damage may occur because of the proximity of these lesions to adjacent articular cartilage.

The knee (medial femoral condyle), the elbow joint (capitellum), and the talus (superior lateral dome) are the most common sites for these lesions. Joint pain is the usual presenting complaint; however, local swelling or locking may be present, particularly if a fragment is free in the joint. Laboratory studies are normal.

Treatment consists of protection of the involved area from mechanical damage. Stable/attached lesions are generally treated with activity modification and immobilization for 3–6 months. Unstable/dislodged lesions are treated surgically with arthroscopic drilling, in order to bring new blood flow to the area, and fixation to stabilize the lesion. For some marginal lesions, it may be worthwhile to drill the necrotic fragment to encourage more rapid vascular in-growth and replacement. If a fragment is free within the joint as a loose body, it must be removed. If large areas of a weight-bearing joint are involved, secondary degenerative arthritis may result. Adolescents have less favorable outcomes with nonoperative therapy.

Pascual-Garrido C, Moran CJ, Green DW, Cole BJ: Osteochondritis dissecans of the knee in children and adolescents. Curr Opin Pediatr 2013;25(1):46–51 [PMID: 23128839].

Polousky JD: Juvenile osteochondritis dissecans. Sports Med Arthrosc Rev 2011;19:56–63 [PMID: 21293239].

NEUROLOGIC DISORDERS INVOLVING THE MUSCULOSKELETAL SYSTEM

ORTHOPEDIC ASPECTS OF CEREBRAL PALSY

Early physical therapy encouraging completion of normal developmental patterns may benefit patients with cerebral palsy. This therapy is most effective during the first few years of life, and should be discontinued when no improvement is apparent.

Bracing and splinting are of questionable benefit, although night splints may be useful in preventing equinus deformity of the ankle, the most common deformity found in this population, or adduction contractures of the hips. Orthopedic surgery is useful for treating joint contractures that interfere with function. Muscle transfers are effective in carefully selected patients with cerebral palsy, and most orthopedic procedures are directed at tendon lengthening or bony stabilization by osteotomy or arthrodesis.

Flexion and adduction of the hip due to hyperactivity of the adductors and flexors may produce a progressive paralytic dislocation of the hip. This can lead to pain and dysfunction, with treatment being difficult and unsatisfactory. The principal preventive measure is abduction bracing, supplemented by release of the adductors and hip flexors in order to prevent dislocation. In severe cases, osteotomy of the femur may be necessary to correct bony deformities of femoral anteversion and coxa valga that are invariably present. Patients with a predominantly athetotic pattern are poor candidates for any surgical procedure or bracing due to largely unpredictable results.

Surgeons must examine patients on several occasions before any operative procedure as it is difficult to predict the surgical outcome in individuals diagnosed with cerebral palsy. Follow-up care with a physical therapist can maximize the anticipated long-term gains and should be arranged before surgery.

Horstmann HM, Hosalkar H, Keenan MA: Orthopaedic issues in the musculoskeletal care of adults with cerebral palsy. Dev Med Child Neurol 2009;51:99–105 [PMID: 19740216].

ORTHOPEDIC ASPECTS OF MYELODYSPLASIA

Early closure of the sac in patients born with spina bifida is the rule, although there has been some hesitancy to provide treatment to all of these patients due to the extremely poor prognosis associated with congenital hydrocephalus, high levels of paralysis, and associated congenital anomalies in some cases. A high percentage of these children have hydrocephalus, which may be evident at birth or shortly thereafter, requiring shunting. Careful urologic evaluation and follow-up must be obtained to prevent complications from bladder dysfunction.

Patients should be examined early by an orthopedic surgeon. The level of neurologic involvement determines the muscle imbalance that will be present to produce deformity with growth. The involvement is often asymmetrical and tends to change during the first 12–18 months of life. Associated musculoskeletal problems may include clubfoot, congenital dislocation of the hip, arthrogryposis-type changes of the lower extremities, and congenital scoliosis and kyphosis. Spina bifida lesions are most common at the L3–L4 level and tend to affect the hip joint, with progressive dislocation occurring during growth due to unopposed hip flexion and adduction forces. Foot deformities are complicated by the fact that sensation is generally absent; these deformities may be in any direction depending on the muscle imbalance present. Spinal deformities develop in a high percentage of these children, with scoliosis present in approximately 40%.

Ambulation may require long leg braces. In children who have a reasonable likelihood of walking, operative treatment consists of reduction of the hip, alignment of the feet in the weight-bearing position, as well as stabilization of the scoliosis. In children who lack active quadriceps function and extensor power of the knee, the likelihood of ambulation is greatly decreased. In such patients, aggressive surgery to the foot and hip region is usually not indicated as it may result in stiffening of the joints and prevent sitting.

The overall treatment of the child with spina bifida should be coordinated in a multidisciplinary clinic where various medical specialists work with therapists, social workers, and teachers to provide the best possible care.

NEOPLASIA OF THE MUSCULOSKELETAL SYSTEM

The poor prognosis of malignant tumors arising in the bone or other tissues derived from the mesoderm makes neoplastic diseases of the musculoskeletal system a serious problem. Fortunately, few benign lesions undergo malignant transformation. Accurate diagnosis depends on correlation of the clinical, radiographic, and microscopic findings. Complaints about the knee should be investigated for tumor, although the usual causes of knee pain are traumatic, infectious, or developmental in origin.

Hashefi M: Ultrasound in the diagnosis of noninflammatory musculoskeletal conditions. Semin Ultrasound CT MR 2011;32(2):74–90 [PMID: 21414544].

OSTEOCHONDROMA

Osteochondroma is the most common benign bone tumor in children. It usually presents as a pain-free mass. When present, pain is caused by bursitis or tendinitis due to irritation by the tumor. Lesions may be single or multiple. Pathologically, the lesion is a bone mass capped with cartilage. These masses result from a developmental defect of the growth plate and tend to grow during childhood and adolescence in proportion to the child’s growth. Males are more affected than females.

Generally, the tumors are present on radiographs in the metaphyseal region of long bones and may be pedunculated or sessile. The cortex of the underlying bone “flows” into the base of the tumor.

An osteochondroma should be excised if it interferes with function, is frequently traumatized, or is large enough to be deforming. The prognosis is excellent. Malignant transformation is very rare.

Gunay C et al: Spinal osteochondroma: a report on six patients and a review of the literature. Arch Orthop Trauma Surg. 2010 Dec;130(12):1459-65. doi: 10.1007/s00402-010-1058-7. Epub 2010 Jan 28. Review [PMID:20107821].

OSTEOID OSTEOMA

Osteoid osteoma is a benign bone-forming lesion. It classically produces night pain that can be relieved by nonsteroidal anti-inflammatory drugs. On physical examination, there usually is tenderness over the lesion. An osteoid osteoma in the upper femur may cause referred pain to the knee.

The radiographic lesion consists of a radiolucent nidus surrounded by dense osteosclerosis that may obscure the nidus. Bone scan shows intense uptake in the lesion. CT scans are confirmatory and delineate the nidus well.

Surgical excision or radiofrequency ablation of the nidus is curative and may be done using computed tomography imaging and a minimally invasive technique. The prognosis is excellent, with no known cases of malignant transformation, although the lesion has a tendency to recur if incompletely excised. The etiology remains unclear.

Laurence N, Epelman M, Markowitz RI, Jaimes C, Jaramillo D, Chauvin NA: Osteoid osteomas: a pain in the night diagnosis. Pediatr Radiol 2012;42(12):1490–1501 [PMID: 23089877].

ENCHONDROMA

Enchondroma (nest of benign cartilage within long bones) is usually a silent lesion unless it produces a pathologic fracture. On radiograph it is radiolucent, usually in a long bone. Speckled calcification may be present. The classic lesion looks as though someone dragged his or her fingernails through clay, making streaks in the bones. Enchondroma is treated by surgical curettage and bone grafting. The prognosis is excellent. Malignant transformation may occur but is very rare in childhood.

CHONDROBLASTOMA

The presenting complaint in chondroblastoma (benign chondral origin lesions typically in the epiphyses [joint ends] of long bones) is pain around a joint. This neoplasm may produce a pathologic fracture. On radiograph, the lesion is radiolucent and usually located in the epiphysis. With little to no reactive bone, calcification is unusual. The lesion is treated by surgical curettage and bone grafting. The prognosis is excellent if complete curettage is performed. There is no known malignant transformation.

Kim J, Kumar R, Raymond AK: Non-epiphyseal chondroblastoma arising in the iliac bone, and complicated by an aneurysmal bone cyst. Skeletal Radiol 2010;39:583–587 [PMID: 19936740].

Zhang K, Gao Y, Dai H, Zhang S, Li G, Yu B: Chondroblastoma of the talus: a case report and literature review. J Foot Ankle Surg 2012;51(2):262–265 [PMID: 22064125].

NONOSSIFYING FIBROMA

Nonossifying fibroma, or benign cortical defect, is nearly always an incidental finding on radiograph. Nonossifying fibroma is a radiolucent lesion eccentrically located in the metaphyseal region of the bone. Usually a thin sclerotic border is evident. Multiple lesions may be present. The most frequent sites are the distal femur and proximal tibia. In general, no treatment is needed because these lesions heal as they ossify with maturation and growth. Rarely, pathologic fractures result from large lesions.

OSTEOSARCOMA

Osteosarcoma is an aggressive form of cancer characterized by chromosomal instability. It is suspected that micro RNAs (non-coding, single-stranded molecules of RNA that regulate gene expression) play an important role in the cancer’s development. In osteosarcoma, the presenting complaint is usually pain in a long bone; however, the patient may present with, loss of function, mass, or limp. Pathological fracture is uncommon. The malignant osseous tumor produces a destructive, expanding, and invasive lesion. A triangle may be adjacent to the tumor, produced by elevated periosteum and subsequent tumor ossification. The lesion may contain calcification and violates the cortex of the bone. Femur, tibia, humerus, and other long bones are the sites usually affected.

Surgical excision (limb salvage) or amputation is indicated based on the extent of the tumor. Adjuvant chemotherapy is routinely used prior to surgical excision. The prognosis is improving, with 60%–70% long-term survival rates being reported in modern series. Death usually occurs as a result of lung metastasis. Patients with osteosarcoma complicated by pathological fracture have lower long-term survival rates than patients with osteosarcoma and no pathological fracture.

Heare T, Hensley MA, Dell’Orfano S: Bone tumors: Osteosarcoma and Ewing’s sarcoma. Curr Opin Pediatr 2009;21(3):365–672 [PMID: 19421061].

Lee RK, Chu WC, Leung JH, Cheng FW, Li CK: Pathological fracture as the presenting fracture in pediatric osteosarcoma. Pediatr Blood Cancer 2013 Jul;60(7):1118-21. doi: 10.1002/pbc.24447. Epub 2012 Dec 31 [PMID: 23281226].

Liang W, Gao B, Fu P, Xu S, Qian Y, Fu Q: The miRNAs in the pathgenesis of osteosarcoma. Front Biosci 2013;18:788–794 [PMID: 23276964].

EWING SARCOMA

In Ewing sarcoma, the presenting complaint is usually pain and tenderness, but fever and leukocytosis may be present. Osteomyelitis is the main differential diagnosis. The lesion may be multicentric. Ewing sarcoma is radiolucent and destroys the cortex, frequently in the diaphysial region. Reactive bone formation may occur about the lesion, seen as successive layers of so-called onion skin layering.

Treatment is with multi-agent chemotherapy, radiation, and surgical resection. Large tumor size, pelvic lesions, and inadequate response to chemotherapy portend a poor prognosis.

Parida L et al: Clinical management of Ewing sarcoma of the bones of the hands and feet: a retrospective single-institution review. J Pediatr Surg 2012;47(10):1806–1810 [PMID: 23084188].

MISCELLANEOUS DISEASES OF BONE AND JOINT

image ESSENTIALS OF DIAGNOSIS & TREATMENT

image Rule out malignant process.

image Rule out pathologic fracture.

image Beware of associated endocrine abnormalities.

image Treatment based on symptoms and location.

FIBROUS DYSPLASIA

Dysplastic fibrous tissue replacement of the medullary canal is accompanied by the formation of metaplastic bone in areas with fibrous dysplasia. Three forms of the disease are recognized: monostotic, polyostotic, and polyostotic with endocrine disturbances (precocious puberty in females, hyperthyroidism, and hyperadrenalism [Albright syndrome]).

imageClinical Findings

A. Symptoms and Signs

The lesion or lesions may be asymptomatic. If present, pain is probably due to pathologic fractures. In females, endocrine disturbances may be present in the polyostotic variety and associated with café au lait spots.

B. Laboratory Findings

Laboratory findings are normal unless endocrine disturbances are present, in which case secretion of gonadotropic, thyroid, or adrenal hormones may be increased.

C. Imaging

The lesion begins centrally within the medullary canal, usually of a long bone, and expands slowly. Pathologic fracture may occur. If metaplastic bone predominates, the contents of the lesion have the density of bone. The disease is often asymmetrical, and limb length disturbances may occur as a result of stimulation of epiphysial cartilage growth. Marked deformity of the bone may result, and a shepherd’s crook deformity of the upper femur is a classic feature of the disease.

imageDifferential Diagnosis

The differential diagnosis includes other fibrous lesions of bone as well as destructive lesions such as unicameral bone cyst, eosinophilic granuloma, aneurysmal bone cyst, nonossifying fibroma, enchondroma, and chondromyxoid fibroma.

imageTreatment

If the lesion is small and asymptomatic, no treatment is needed. If the lesion is large and produces or threatens pathologic fracture, curettage and bone grafting are indicated.

imagePrognosis

Unless the lesions affect epiphysial growth, the prognosis for patients with fibrous dysplasia is good. Lesions tend to enlarge during the growth period but are stable during adult life. Malignant transformation is rare.

UNICAMERAL BONE CYST

Unicameral bone cysts occur in the metaphysis of a long bone, usually in the femur or humerus. A cyst begins in the medullary canal adjacent to the epiphysial cartilage. It probably results from some fault in enchondral ossification (the process where bone is formed from cartilaginous precursors). The cyst is considered active as long as it abuts onto the metaphysial side of the epiphysial cartilage, and there is a risk of growth arrest with or without treatment. When a border of normal bone exists between the cyst and the epiphysial cartilage, the cyst is inactive. The lesion is usually identified when a pathologic fracture occurs, producing pain. Laboratory findings are normal. On radiograph, the cyst is identified centrally within the medullary canal, producing expansion of the cortex and thinning over the widest portion of the cyst. Treatment consists of curettage and bone grafting. The cyst may heal after a fracture.

Mik G et al: Results of a minimally invasive technique for treatment of unicameral bone cysts. Clin Orthop Relat Res 2009 Nov;467(11):2949-54. doi: 10.1007/s11999-009-1008-2. Epub 2009 Aug 4 [PMID: 19653053].

ANEURYSMAL BONE CYST

Aneurysmal bone cyst is similar to unicameral bone cyst, except it contains blood rather than clear fluid. It usually occurs in a slightly eccentric position in a long bone, expanding the cortex of the bone but not breaking the cortex. Involvement of the flat bones of the pelvis is less common. On radiographs, the lesion appears somewhat larger than the width of the epiphysial cartilage, distinguishing it from a unicameral bone cyst.

Chromosomal abnormalities have been associated with aneurysmal bone cysts. The lesion may appear aggressive histologically, and it is important to differentiate it from osteosarcoma or hemangioma. Treatment is by curettage and bone grafting. The prognosis is good.

INFANTILE CORTICAL HYPEROSTOSIS (CAFFEY SYNDROME)

Infantile cortical hyperostosis is a benign disease of unknown cause that has its onset before age 6 months and is characterized by irritability; fever; and nonsuppurating, tender, painful swellings. Swellings may involve almost any bone of the body and are frequently widespread. Classically, swellings of the mandible and clavicle occur in 50% of patients; swellings of the ulna, humerus, and ribs also occur. The disease is limited to the shafts of bones and does not involve subcutaneous tissues or joints. It is self-limited but may persist for weeks or months. Anemia, leukocytosis, an increased ESR, and elevation of the serum alkaline phosphatase concentration are usually present. Cortical hyperostosis is demonstrable by a typical radiographic appearance and may be diagnosed on physical examination by an experienced healthcare provider. In rare instances, a biopsy may be needed to confirm the diagnosis.

Fortunately, the disease appears to be decreasing in frequency. Indomethacin may be useful for treatment. The prognosis is good, and the disease usually terminates without deformity.

GANGLION

A ganglion is a smooth, small cystic mass connected by a pedicle to the joint capsule, usually on the dorsum of the wrist. It may also occur in the tendon sheath over the flexor or extensor surfaces of the fingers. These ganglia can be excised if they interfere with function or cause persistent pain.

BAKER CYST

A Baker cyst is a herniation of the synovium in the knee joint into the popliteal region. In children, the diagnosis may be made by aspiration of mucinous fluid, but the cyst nearly always disappears with time. Whereas Baker cysts may be indicative of intra-articular disease in the adult, they occur without internal derangement in children and rarely require excision.

Sit M, Higgs JB: Non-popliteal synovial rupture. J Clin Radiol 2009;15:185–189 [PMID: 19390451].

NATIONAL QI/QA INITIATIVES IN ORTHOPEDICS

The Pediatric Orthopedic Society of North America (POSNA) has developed an initiative called the POSNA QSVI (Quality, Safety, and Value Initiative). This initiative is designed to optimize management of children with orthopedic issues. Within POSNA, this initiative has branched into many subcommittees with charges that include education, quality measurements, best practice guidelines, research, and benchmarking.