BASIC SCIENCE QUESTIONS
1. There are eight pulleys on the flexor surface of each finger. The two pulleys that are the most important to prevent bowstringing of the flexor tendons are
A. A2 and A4
B. A1 and A3
C. A2 and C2
D. A1 and C1
Answer: A
In the hand, the pulleys maintain the long flexor tendons in close apposition to the fingers and thumb. There are no extensor pulleys within the hand. Each finger has five annular and three cruciate pulleys (Fig. 44-1). The second and fourth (A2 and A4) pulleys are the critical structures that prevent bowstringing of the finger. The remaining pulleys can be divided as needed for surgical exposure or to relieve a stricture area. (See Schwartz 9th ed., p 1614.)
FIG. 44-1. Drawing of anteroposterior and lateral view of the pulley system.
2. In the proximal forearm, the radial artery travels deep to which of the following muscles?
A. Flexor carpi radialis
B. Brachioradialis
C. Palmaris longus
D. Flexor digitorum superficialis
Answer: B
The radial artery travels under the brachioradialis muscle in the forearm. At the junction of the middle and distal thirds of the forearm, the artery becomes superficial and palpable, passing just radial to the FCR tendon. At the wrist level, the artery splits into two branches. The smaller, superficial branch passes volarly into the palm to contribute to the superficial palmar arch. The larger branch passes dorsally over the scaphoid bone, under the EPL and EPB tendons (known as the anatomic snuffbox), and back volarly between the proximal thumb and index finger meta-carpals to form the superficial palmar arch. (See Schwartz 9th ed., p 1614.)
3. Initial therapy for a patient with a functionally significant Duputryren’s contracture is
A. Physical therapy
B. Steroid injection
C. Splinting
D. Surgery
Answer: D
Most nonoperative management techniques will not delay the progression of disease. Corticosteroid injections may soften nodules and decrease discomfort associated with them, but are ineffective against cords. Splinting similarly has been shown not to retard disease progression. Injectable clostridial collagenase has shown promise in clinical trials but has not yet been reported in large or long-term series. It also is not yet commercially available. For patients with advanced disease, including contractures of the digits that limit function, surgery is the mainstay of therapy. Although rate of progression should weigh heavily in the decision of whether or not to perform surgery, general guidelines are MP contracture of 30° or more and/or PIP contracture of 20° or more. (See Schwartz 9th ed., p 1630.)
4. In patients with severe arthritis of the MP joint unresponsive to medication, arthrodesis will
A. Relieve pain
B. Maintain extension
C. Maintain flexion
D. All of the above
Answer: A
When conservative measures fail, two principal surgical options exist: arthrodesis and arthroplasty. The surgeon and patient must decide together as to whether conservative measures have failed. Surgery for arthritis, whether arthrodesis or arthroplasty, is performed for the purpose of relieving pain. Arthrodesis, fusion of a joint, provides excellent relief of pain and is durable over time. However, it comes at the price of total loss of motion. Silicone implant arthroplasty has been available for over 40 years. Rather than a true replacement of the joint, the silicone implant acts as a spacer between the two bones adjacent to the joint. This allows for motion without bony contact that would produce pain. Long-term studies have shown that all implants fracture over time, but usually continue to preserve motion and pain relief. (See Schwartz 9th ed., p 1629.)
5. The movement of the fingers away from the middle finger is called
A. Abduction
B. Adduction
C. Supination
D. Pronation
Answer: A
The hand is highly mobile in space to allow maximum flexibility in function. As such, a number of directions particular to the hand are necessary to properly describe position, motion, etc. Palmar (or volar) refers to the anterior surface of the hand in the anatomic position; dorsal refers to the posterior surface in the anatomic position. The hand can rotate at the wrist level; rotation to bring the palm down is called pronation, to bring the palm up is called supination. Because the hand can rotate in space, the terms medial and lateral are avoided. Radial and ulnar are used instead as these terms do not vary with respect to the rotational position of the hand. Abduction and adduction, when used on the hand, refer to movement of the digits away from and toward the middle finger, respectively (Fig. 44-2). (See Schwartz 9th ed., p 1610-1612.)
FIG. 44-2. Terminology of common hand motions. (Reproduced with permission from American Society for Surgery of the Hand (ed): The Hand: Examination and Diagnosis, 3rd ed. Copyright © Elsevier, 1990.) (continued)
FIG. 44-2. (continued)
6. All of the muscles that flex the interphalangeal joints of the fingers originate from
A. The medial condyle of the humerus
B. The lateral condyle of the humerus
C. The distal shaft of the humerus
D. The deltoid tuberosity of the humerus
Answer: A
The long flexors of the fingers all originate from the medial epicondyle of the humerus. The flexor digitorum superficialis (FDS) inserts on the base of the middle phalanx of each finger and primarily flexes the PIP joint. The flexor digitorum profundus (FDP) inserts on the base of the distal phalanx and primarily flexes the DIP joint. The flexor pollicis longus (FPL) originates more distally, from the ulna, radius, and interosseous membrane between them in the forearm. It inserts on the base of the distal phalanx of the thumb and primarily flexes the IP joint. All of these tendons can also flex the more proximal joint(s) in their respective rays. All of these muscles are innervated by the median nerve (or its branches) except the FDP to the ring and small finger, which are innervated by the ulnar nerve. (See Schwartz 9th ed., p 1610;1613.)
CLINICAL QUESTIONS
1. Appropriate management of a paronychia includes
A. Needle puncture of the nail
B. Incision and drainage through the lateral nail plate
C. Elevation of the nail fold from the nail plate
D. None of the above
Answer: C
Early treatment of a paronychia is warm compresses or soaks and an antistaphylococcal antibiotic. First-generation cephalosporins have traditionally been used, but the increasing prevalence of methicillin-resistant S. aureus has led the authors to begin empiric treatment with vancomycin. Fluctuant swelling or visible pus should be drained with a Freer elevator or the bevel of an 18-gauge needle inserted between the nail and nail fold (Fig. 44-3). If the abscess resides under the eponychial fold, then a proximally based flap of eponychium can be reflected up to allow for better drainage. An abscess that extends below the nail necessitates partial removal of the nail plate. A thin gauze wick should be inserted for 24 to 48 hours to maintain patency of the drainage tract. (See Schwartz 9th ed., p 1634.)
FIG. 44-3. Paronychia. A. Fluctuance in the nail fold is the hallmark of this infection. B. Technique of drainage between the nail plate and nail fold.
2. The Jahss maneuver is used to reduced fractures of the
A. Scaphoid
B. Lunate
C. 5th metacarpal
D. 2nd metacarpal
Answer: C
Angulated fractures of the small finger MC (‘boxer’s fracture’) are another common injury seen in the ER. Typical history is that the patient struck another individual or rigid object with a hook punch. These often are stable after reduction using the Jahss maneuver (Fig. 44-4). (See Schwartz 9th ed., p 1620.)
FIG. 44-4. The Jahss maneuver. The surgeon fully flexes the patient’s small finger into the palm and secures it in his distal hand. The proximal hand controls the wrist and places the thumb on the patients fracture apex (the most prominent dorsal point). The examiner distracts the fracture, pushes dorsally with the distal hand (up arrow) and resists dorsal motion with the proximal hand (down arrow).
3. Phalen’s test is used in the diagnosis of
A. Postoperative neuroma
B. Scaphoid nonunion
C. Carpal tunnel syndrome
D. Trigger finger
Answer: C
Physical examination of a patient with suspected carpal tunnel syndrome should begin with inspection. Look for evidence of wasting of the thenar muscles. Tinel’s sign should be tested over the median nerve from the volar wrist flexion crease to the proximal palm. Phalen’s test (maximal flexion of the wrist for 1 minute) and reverse Phalen’s (maximal extension) are tested. Applying pressure over the carpal tunnel while flexing the wrist has been shown in one series to have the highest sensitivity as compared to Phalen’s and Tinel’s signs. Strength of the thumb in opposition also should be tested. (See Schwartz 9th ed., p 1627.)
4. In a young, healthy patient, the most appropriate treatment for a nondisplaced scaphoid wrist fracture is
A. Immobilization in a thumb spica cast for 4 weeks
B. Immobilization in a wrist cock-up cast for 6 weeks
C. Percutaneous screw fixation
D. Open reduction and plate fixation
Answer: C
In general terms, most nondisplaced fractures do not require surgical treatment. The scaphoid bone of the wrist is a notable exception to this rule. Due to peculiarities in its vascular supply, particularly vulnerable at its proximal end, nondisplaced scaphoid fractures can fail to unite in up to 20% of patients, even with appropriate immobilization. Recent developments in hardware and surgical technique have allowed stabilization of the fracture with minimal surgical exposure. One prospective randomized series of scaphoid wrist fractures demonstrated shortening of time to union by up to 6 weeks in the surgically treated group, but no difference in rate of union. Surgical treatment for nondisplaced scaphoid fractures is not indicated for all patients, but may be useful in the younger, more active patient who would benefit from an earlier return to full activity. (See Schwartz 9th ed., p 1619.)
5. A chemical burn to the hand with hydrofluoric acid should be treated with
A. Sodium bicarbonate irrigation
B. Calcium gluconate gel
C. Early tangential excision
D. Dilute sodium hypochlorite irrigation
Answer: B
Chemical burns of the hands are continuously flushed with water until the pain significantly decreases or stops. Acid burns may require 20 minutes of irrigation while alkali burns may require several hours of irrigation. Hydrofluoric acid burns are a special consideration. This type of burn is marked by slow onset of severe pain as the compound reaches deeper tissues. Hydrofluoric acid avidly binds tissue and circulating calcium, resulting in hypocalcemia that can lead to cardiac arrhythmia and arrest. Following water irrigation, a mixture of calcium gluconate in an aqueous jelly is placed into a surgical glove, which is then used to cover the burned hand. Effectiveness of treatment is assessed by relief of pain. If topical therapy does not relieve pain, then locally injected intra-arterial calcium may be necessary. (See Schwartz 9th ed., p 1641.)
6. An injury to a finger flexor tendon at the level of the web space is a
A. Zone I injury
B. Zone II injury
C. Zone III injury
D. Zone IV injury
Answer: B
Flexor tendon injuries are described based on zones (Fig. 44-5). Up until 40 years ago, zone 2 injuries were always reconstructed and never repaired primarily due to concern that the bulk of repair within the flexor sheath would prevent tendon glide. The work of Dr. Kleinert and colleagues at the University of Louisville changed this ‘axiom’ and established the principle of primary repair and early controlled mobilization postoperatively. Flexor tendon injuries should always be repaired in the OR. Although they do not need to be repaired on the day of injury, the closer to the day of injury they are repaired, the easier it will be to retrieve the retracted proximal end. (See Schwartz 9thed., p 1621.)
FIG. 44-5. The zones of flexor tendon injury: I. Flexor digitorum superficialis insertion to the flexor digitorum profundus insertion. II. Start of the A1 pulley to the flexor digitorum superficialis insertion. III. End of the carpal tunnel to the start of the A1 pulley. IV. Within the carpal tunnel. V. Proximal to the carpal tunnel.
7. The most common location for a ganglion cyst is
A. The dorsal wrist
B. The volar wrist
C. Flexor tendon sheath
D. Dorsal DIP joint
Answer: A
Ganglion cysts are the most common soft tissue tumors in the hand. These lesions can be painful and usually are found on the dorsal wrist, followed by the volar wrist, flexor tendon sheath, and the dorsal DIP joint (the mucous cyst). These non-neoplastic, mucinous, fluid-filled pseudocysts arise from synovial linings of irritated and inflamed joints, ligaments, and tendon sheaths. As they have no epithelial lining, the focus of treatment is the site of production or leakage of the synovial fluid, rather than the cyst itself. (See Schwartz 9th ed., p 1638.)
8. The most common congenital anomaly of the hand is
A. Polydactyly
B. Syndactyly
C. Constriction band syndrome
D. Radial club hand
Answer: B
Syndactyly, in which two or more fingers are fused together, is the most common congenital hand deformity. Syndactyly occurs in seven out of every 10,000 live births. There is a familial tendency to develop this deformity. This deformity often involves both hands, and males are more often affected than females. (See Schwartz 9th ed., p 1642.)
9. The incision to treat a felon is placed
A. Laterally on each side of the finger
B. Longitudinally, centered on the area of maximal fluctuence
C. Between the nail fold and nail plate
D. Transversely across the tip of the finger
Answer: B
The procedure to drain a felon is straightforward (Fig. 44-6). A digital block is performed. This is followed by a short skin incision. Only the skin is incised. Pus is evacuated using a blunt instrument to decrease the chance of severing a digital nerve or entering the tendon sheath. Gauze is loosely packed into the wound to prevent skin closure. A loose dressing and finger splint is applied. The hand is elevated and splinted. (See Schwartz 9th ed., p 1634.)
FIG. 44-6. A and B. The area of purulence in a felon is located in the pad of the distal phalanx as shown. B. A longitudinally oriented incision is made over the area of maximal fluctuance; this incision should not cross the distal interphalangeal joint crease. See text for additional details.
10. Which of the following is NOT one of Kanavel’s signs of flexor tendon sheath infection?
A. Finger held in slight flexion
B. Fusiform swelling
C. Tenderness along the flexor tendon sheath
D. Pain with passive flexion of the finger
Answer: D
Patients with infectious flexor tenosynovitis (FTS) present with complaints of pain, redness, and fever. Physical examination reveals Kanavel’s ‘cardinal’ signs of flexor tendon sheath infection, which are finger held in slight flexion, fusiform swelling, tenderness along the flexor tendon sheath, and pain over the flexor sheath with passive extension of the digit (Fig. 44-7A). (See Schwartz 9th ed., p 1636.)
FIG. 44-7. Suppurative flexor tenosynovitis of the ring finger. A. The finger demonstrates fusiform swelling and flexed posture. B. Proximal exposure for drainage. C. Distal drainage incision.
11. The most important part of the initial management of a burn of the hand is
A. Elevation
B. Early range of motion exercise
C. Early débridement
D. Early grafting
Answer: A
Edema formation in burned hands hinders motion and may be a factor in later contracture formation. The hands must be elevated above the level of the heart to minimize edema formation. This is the most important initial step in the management of hand burns and can be done in any sized burn without hindering resuscitation, pulmonary, or other critical care management. (See Schwartz 9th ed., p 1640.)
12. The best initial treatment for “trigger finger” is
A. Splinting for 4-6 weeks
B. Physical therapy
C. Steroid injection
D. Surgery
Answer: C
Stenosing tenosynovitis of the flexor tendon sheath, also known as trigger finger (TF), is one of the most common upper limb problems to be encountered in hand surgery practice. The condition starts with discomfort in the palm during movements of the involved digits. Gradually, the flexor tendon causes painful popping or snapping as the patient flexes and extends the digit. The patient often will present with a digit locked in a flexed position, which may require gentle passive manipulation to regain full extension.
Nonoperative treatment includes limiting the activities that aggravate the condition. Splinting and/or oral anti-inflammatory medication may help. If symptoms continue, a corticosteroid injection into the tendon sheath at the pulley is often effective in relieving the trigger digit. The authors prefer triamcinolone acetonide (40 mg/mL) mixed with 0.5% plain bupivacaine. The needle is inserted at the MC head, advanced until bone is encountered, and then withdrawn approximately 0.5 mm until resistance gives way, allowing the medication to be injected. Approximately 1 mL is deposited in the tendon sheath. The needle is withdrawn and pressure is applied. Fingers with irreducible flexion contractures should be treated with surgery, not steroid injection. (See Schwartz 9th ed., p 1631.)
13. The primary symptom in De Quervain’s tenosynovitis is pain in the
A. Radial wrist
B. Ulnar wrist
C. Dorsal wrist
D. Volar wrist
Answer: A
Patients with De Quervain’s tenosynovitis usually present with complaints of pain, several weeks to months in duration, along the radial aspect of the wrist aggravated by thumb motion. The most common symptoms are pain when grasping or pinching and tenderness at the first dorsal compartment, where the abductor policis longus and extensor policis brevis pass over the wrist joint (see Fig. 44-8). In some patients, a lump or thickened mass can be felt in the area 1 to 2 cm proximal to the radial styloid. Severe, sharp pain can be elicited by having the patient flex the thumb across the palm, make a fist, and then ulnarly deviate the wrist (Finkelstein’s test) (Fig. 44-9). There should be no tenderness in the forearm proximal to the first dorsal compartment. (See Schwartz 9th ed., p 1632, image 44-8 on pg 1613.)
FIG. 44-8. Cross-section of the wrist at the midcarpal level. The relative geography of the neurologic and tendinous structures can be seen. The transverse carpal ligament (TCL) is the roof of the carpal tunnel, passing volar to the median nerve and long flexor tendons. The TCL is also the floor of the ulnar tunnel, or Guyon’s canal, passing dorsal to the ulnar artery and nerve. The wrist and digital extensor tendons are also seen, distal to their compartments on the distal radius and ulna. Bones: C = capitate; H = hamate; P = pisiform; S = scaphoid. Tendons (flexor digitorum superficialis is volar to flexor digitorum profundus within the carpal tunnel): 2 = index finger; 3 = middle finger; 4 = ring finger; 5 = small finger. A = artery; APL = abductor pollicis longus; ECRB = extensor carpi radialis brevis; ECRL = extensor carpi radialis longus; ECU = extensor carpi ulnaris; EDC = extensor digitorum communis; EDQ = extensor digiti quinti; EIP = extensor indices proprius; EPB = extensor pollicis brevis; EPL = extensor pollicis longus; FCR = flexor carpi radialis; FPL = flexor pollicis longus; N = nerve.
FIG. 44-9. Finkelstein’s test. The patient places the thumb in the palm and makes a loose fist. The examiner then ulnarly deviates the patient’s wrist (as indicated by the arrow). Pain at the first dorsal compartment with this maneuver is a positive response.
14. The most common benign bone tumor of the hand is
A. Lipoma
B. Fibroma
C. Enchondroma
D. Giant cell tumor of the tendon sheath
Answer: C
Enchondromas arise from cartilage and are the most common primary bone tumors of the hand. These lesions account for >90% of bone tumors seen in the hand. The proximal phalanges are the most common sites of occurrence, followed by the MC bones. On radiographs, an enchondroma usually is seen as a well-defined radiolucent lesion in the diaphysis or metaphysis and also may have a well-defined sclerotic rim. Although these tumors are benign, local bony destruction can lead to pathologic fracture. (See Schwartz 9th ed., p 1638.)
15. Which of the following is the most appropriate treatment for a crush injury to the fingertip with a laceration greater than 1 cm2 with less than 50% of the nailbed remaining?
A. Primary repair
B. Débridement and wound care to allow healing by secondary intention
C. Operative shortening of the bone for primary stump closure
D. Volar V-Y flap closure of the laceration
Answer: C
For the common scenario, complex lacerations with minimally displaced fracture(s) and no loss of perfusion, the wound is cleansed, closed, and splinted in the ER. To properly assess the nail bed, the nail plate (hard part of the nail) should be removed. A Freer periosteal elevator is well suited for this purpose. Lacerations are repaired with 6-0 fast gut suture. Great care must be taken when suturing as excessive traction with the needle can further lacerate the tissue. After repair, the nail folds are splinted with the patient’s own nail plate (if available) or with aluminum foil from the suture pack. This is done to prevent scarring from the nail folds down to the nail bed that would further compromise healing of the nail. In some situations, tissue may have been avulsed in the injury and be unavailable for repair. Choice of treatment options depends on the amount and location of tissue loss (Fig. 44-10). For wounds 1 cm2 with no exposed bone, secondary intention will produce excellent functional and aesthetic results. For larger wounds or wounds with bone exposed, one must decide if the finger is worth preserving at the current length or if shortening to allow for primary closure is a better solution. A useful guideline is the amount of fingernail still present; if greater than 50% is present, local or regional flap coverage may be a good solution. (See Schwartz 9th ed., p 1622.)
FIG. 44-10. Treatment algorithm for management of fingertip injuries. See text for description of flaps.
16. The primary treatment of herpetic whitlow is
A. Dry dressings
B. Wound débridement
C. Intralesional acyclovir
D. Intravenous acyclovir
Answer: A
Herpetic whitlow usually resolves spontaneously in 2 to 3 weeks. The main goals of treatment are to prevent both oral inoculation and spread of the infection, as well as to obtain symptomatic relief. The involved digit should be kept covered with a dry dressing. Some authors recommend treatment with oral acyclovir for 10 days if the diagnosis is made early in symptom onset, although acyclovir has not been demonstrated to shorten the course of this self-limited infection. Stronger evidence exists to recommend oral acyclovir for recurrent infections during the prodromal stage, as well as in immunocompromised patients. Infection can recur in 30 to 50% of patients, but the initial infection is typically the most severe. (See Schwartz 9th ed., p 1635.)