Schwartz's Principles of Surgery ABSITE and Board Review, 9th Ed.

CHAPTER 45. Plastic and Reconstructive Surgery

BASIC SCIENCE QUESTIONS

1. The first stage of healing in a skin graft is

A. Revascularization

B. Inosculation

C. Imbibition

D. None of the above

Answer: C

Skin graft take occurs in three phases, imbibition, inosculation, and revascularization. Plasmatic imbibition refers to the first 24 to 48 hours after skin grafting, during which time a thin film of fibrin and plasma separates the graft from the underlying wound bed. It remains controversial whether this film provides nutrients and oxygen to the graft or merely a moist environment to maintain the ischemic cells temporarily until a vascular supply is re-established. After 48 hours a fine vascular network begins to form within the fibrin layer. These new capillary buds interface with the deep surface of the dermis and allow for transfer of some nutrients and oxygen. This phase, called inosculation, transitions into revascularization, the process by which new blood vessels either directly invade the graft or anastomose to open dermal vascular channels and restore the pink hue of skin. These phases are generally complete by 4 to 5 days after graft placement. During these initial few days the graft is most susceptible to deleterious factors such as infection, mechanical shear forces, and hematoma or seroma. (See Schwartz 9th ed., p 1650.)

2. The chance an offspring will have a cleft lip if one of the parents has a cleft lip is

A. 4%

B. 10%

C. 25%

D. 100%

Answer: A

Factors that likely increase the incidence of clefting include increased parental age, drug use and infections during pregnancy, smoking during pregnancy, and a family history of orofacial clefting. The increased chance of clefting when there is an affected parent is approximately 4%. (See Schwartz 9th ed., p 1658.)

3. The deepest layer of the scalp is

A. Subcutaneous tissue

B. Loose areolar tissue

C. Pericranium

D. Galea aponeurotica

Answer: C

The scalp is formed of five layers: Skin, sub Cutaneous tissue, galea Aponeurotica, Loose areolar tissue, and Pericranium (SCALP). (See Schwartz 9th ed., p 1675.)

CLINICAL QUESTIONS

1. The best incision to excise a lesion on the bridge of the nose is

A. Vertical

B. Horizontal

C. Oblique

D. Circular

Answer: B

Although the term Langer’s lines often is used interchangeably with the term relaxed skin tension lines, the former lines describe skin tension vectors observed in the stretched integument of cadavers exhibiting rigor mortis, whereas the latter lines lay perpendicular to and more accurately reflect the action of underlying muscle. Kraissl’s lines, which run along natural wrinkles and skin creases, tend also to follow the relaxed skin tension lines (Fig. 45-1). Relaxed skin tension lines may be exploited to create incisions and reconstructions that minimize anatomic distortion and improve cosmesis. (See Schwartz 9thed., p 1648.)

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FIG. 45-1. Relaxed skin tension lines. (Reprinted with permission from Wilhelmi BJ, Blackwell SJ, Phillips LG: Langer’s lines: To use or not to use. Plast Reconstr Surg 104:208, 1999.)

2. The first step in the treatment of a newborn with a complex cleft lip and palate is

A. Nasoalveolar molding prosthetics in infancy, followed by staged repair

B. Repair of the cleft lip at 3 months of age, followed by the palate repair

C. Repair of the cleft palate at 6 months of age, followed by the lip repair

D. Single stage repair (lip and palate) at 9-12 months of age

Answer: A

Attempts to lessen the deformity and set the stage for the surgical repair of the lip and nose begin with a process known as presurgical infant orthopedics (PSIO), which includes procedures such as nasoalveolar molding (NAM). NAM repositions the neonatal alveolar segments, brings the lip elements into close approximation, stretches the deficient nasal components, and turns wide complete clefts into the morphology of narrow ‘incomplete’ clefts. After PSIO with NAM, the definitive single-stage cleft lip and nose repair is performed at 3 to 6 months of age. With this initial operation, the lip deformity is repaired and a primary nasoplasty reconstructs the cleft lip nasal deformity. If the family does not have access to PSIO or have the resources for this time-intensive therapy, a cleft lip adhesion can be performed as an initial stage in the repair. The preliminary cleft lip adhesion unites the upper lip and nasal sill, truly converting complete clefts into incomplete clefts. A cleft lip adhesion is performed in the first or second month of life, and the definitive cleft lip and nose repair follows at 4 to 6 months. After the definitive cleft lip and nose repair, the cleft palate is repaired in a single stage at 9 to 12 months of age. (See Schwartz 9th ed., p 1658.)

3. Which is the first fracture repaired in a patient with multiple facial fractures (panfacial fracture)?

A. Mandibular

B. Maxillary

C. Nasomaxillary

D. Zygomatic

Answer: D

Fractures of multiple bones in various locations fall into the category of panfacial fracture. These may involve frontal and maxillary sinus fractures, NOE fractures, orbital and ZMC fractures, palatal fractures, and complex mandible fractures. The difficulty in the repair of these injuries lies not in the technical aspects of fixation but in the re-establishment of normal relationships between facial features in the absence of all pretraumatic reference points. Without proper correction of bony fragment relationships, facial width is exaggerated and facial projection is lost. The key point in approaching the patient with a panfacial fracture is first to reduce and repair the zygomatic arches and frontal bar to establish the frame and width of the face. The nasomaxillary and zygomaticomaxillary buttresses may then be repaired within this correct frame. Next, the maxilla may be reduced to this framework, followed by palatal fixation if needed. Finally, now that the midface relationships have been corrected, maxillary-mandibular fixation can be applied with the mandible in correct occlusion followed by plating of any mandibular fractures. (See Schwartz 9th ed., p 1672.)

4. Involution of a hemangioma occurs in 50% of children by

A. 6 months of age

B. 1 year of age

C. 2 years of age

D. 5 years of age

Answer: D

Hemangioma growth frequently peaks before the first year, and then the lesions enter the involuting phase in which growth is commiserate with the child. The involuting phase is characterized by diminishing endothelial activity and luminal enlargement. The lesion begins to ‘gray,’ losing its intense reddish color and taking on a purple-gray shade with overlying ‘crepe paper’ skin. The involution phase continues until 5 to 10 years of age. Regression of the lesion is then complete. The involuted phase begins in 50% of children by 5 years of age and in 70% by 7 years. (See Schwartz 9th ed., p 1667.)

5. Conditioning of a transverse rectus abdominus myocutaneous (TRAM) flap can be achieved by

A. Placing ice packs on the abdominal wall for 1 hour before surgery

B. Placing ice packs on the abdominal wall for 1 hour × 7 days before surgery

C. Dividing the inferior epigastric artery 2 weeks before surgery

D. Dividing the superior epigastric artery 2 weeks before surgery

Answer: C

Conditioning refers to any procedure that increases the reliability of a flap. Invoking the delay phenomenon, for example, has improved the survival of flaps whose use is frequently complicated by unpredictable partial necrosis, such as the pedicled transverse rectus abdominis myocutaneous (TRAM) flap. The procedure can be particularly useful in patients at higher risk, such as those who are obese, smoke, or have received radiotherapy. One method of delay for the pedicled TRAM flap is to divide a major portion of its blood supply, the deep inferior epigastric artery on both sides, approximately 2 weeks before transfer. In response, blood from the anatomic angiosome of the superior epigastric artery appears to flow into that of the interrupted deep inferior epigastric artery via intervening choke vessels. As a result, the flap becomes conditioned to rely on the superior epigastric artery. The TRAM flap can then be transferred based on the superior epigastric artery with less risk of its distal portions becoming ischemic and possibly necrotic. (See Schwartz 9th ed., p 1654.)

6. Which of the following has the highest degree of secondary contraction?

A. Thin split-thickness skin graft

B. Thick split-thickness skin graft

C. Meshed thick split-thickness skin graft

D. Full-thickness skin graft

Answer: A

Many of the characteristics of a split-thickness graft are determined by the amount of dermis present. Less dermis translates into less primary contraction (the degree to which a graft shrinks in dimensions after harvesting and before grafting), more secondary contraction (the degree to which a graft contracts during healing), and better chance of graft survival. Thin split grafts have low primary contraction, high secondary contraction, and high reliability of graft take, often even in imperfect recipient beds. Thin grafts, however, tend to heal with abnormal pigmentation and poor durability compared with thick-split grafts and full-thickness grafts. Thick-split grafts have more primary contraction, show less secondary contraction, and may take less hardily. Split grafts may be meshed to expand the surface area that can be covered. This technique is particularly useful when a large area must be resurfaced, as in major burns. Meshed grafts usually also have enhanced reliability of engraftment, because the fenestrations allow for egress of wound fluid and excellent contour matching of the wound bed by the graft. (See Schwartz 9th ed., p 1651.)

7. The generally longest reliable length:width ratio for a random pattern flap is

A. 1:1

B. 2:1

C. 3:1

D. 4:1

Answer: C

Random pattern flaps have a blood supply based on small, unnamed blood vessels in the dermal-subdermal plexus, as opposed to the discrete, well-described, directional vessels of axial pattern flaps (Fig. 45-2). Random flaps are typically used to reconstruct relatively small, full-thickness defects that are not amenable to skin grafting. Unlike axial pattern flaps, random flaps are limited by their geometry. The generally accepted reliable length:width ratio for a random flap is 3:1. (See Schwartz 9th ed., p 1651.)

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FIG. 45-2. Random pattern transposition flap.

8. Which of the following is a component of the Klippel-Trénaunay syndrome?

A. Capillary malformations

B. Venous malformations

C. Lymphatic malformations

D. All of the above

Answer: D

Vascular malformations are subclassified by vessel type, such as lymphatic, capillary, venous, or arterial, and by rheologic characteristics, such as slow flow and fast flow. Slow-flow lesions include capillary malformations (CMs) and telangiectasias, lymphatic malformations (LMs), and venous malformations (VMs). Fast-flow lesions include arterial malformations (AMs) and arteriovenous malformations (AVMs). In addition, there are combined malformations. One such combined lesion occurs in Klippel-Trénaunay syndrome in which CMs, LMs, and VMs are found and may be associated with soft tissue and skeletal hypertrophy in one or more of the limbs. (See Schwartz 9th ed., p 1667.)

9. The treatment of stage II pressure sores is

A. Local wound care only

B. Extensive débridement and local wound care

C. Direct closure

D. Skin grafting

Answer: A

Pressure ulcers are described by their stage, based on depth of tissue injury (Table 45-1). Stage I and II ulcers are treated conservatively with dressing changes and basic pressure ulcer prevention strategies as already discussed. Patients with stage III or IV ulcers should be evaluated for surgery. (See Schwartz 9th ed., p 1694.)

TABLE 45-1 National Pressure Ulcer Advisory Panel staging system

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10. Which of the following is one of the most common locations for orbital fractures?

A. Superior

B. Laterosuperior

C. Lateral

D. Medial

Answer: D

Orbital fractures may involve the orbital roof, floor, or lateral or medial walls. The most common orbital fracture is the orbital floor blow-out fracture caused by direct pressure to the globe and sudden increase in intraorbital pressure. Because the medial floor and inferior medial wall are made of the thinnest bone, fractures occur most frequently at these locations. (See Schwartz 9th ed., p 1671.)

11. The most appropriate treatment of a septal hematoma following blunt trauma to the nose is

A. Observation

B. Aspiration

C. Incision and drainage

D. Operative repair of the fracture

Answer: C

The nose is the most common facial fracture site due to its prominent location, and such fracture can involve the cartilaginous nasal septum, the nasal bones, or both. It is important to perform an intranasal examination to determine whether a septal hematoma is present. If present, a septal hematoma must be incised, drained, and packed to prevent pressure necrosis of the nasal septum and long-term midvault collapse. (See Schwartz 9th ed., p 1672.)

12. What is the maximum defect (percent tissue lost) of the upper eyelid that can be repaired primarily?

A. 5%

B. 10%

C. 25%

D. 40%

Answer: C

Defects comprising 25% of the upper eyelid can generally be closed primarily in pentagonal approximating fashion. For defects involving 25 to 50% of the upper eyelid, lateral canthotomy (release of the lateral canthal tendon) and cantholysis (release of the superior limb of the lateral palpebral tendon) can be performed to allow advancement and are often combined with use of a lateral semicircular flap. Defects larger than 50% of the upper eyelid may be reconstructed with a Cutler-Beard full-thickness advancement flap or a modified Hughes tarsoconjunctival advancement flap. (See Schwartz 9th ed., p 1674.)

13. The maximum width (at the umbilicus) of a midline abdominal wound that can be closed by the component separation technique is

A. 6 cm

B. 12 cm

C. 18 cm

D. 24 cm

Answer: C

The separation-of-components procedure has enjoyed much success in closing large midline defects without resorting to mesh. This procedure involves advancement of bilateral myofascial flaps consisting of the anterior rectus fascia/rectus abdominis/internal oblique/transversus abdominis muscle complex. Mobility of this myofascial unit is created by release of the external oblique muscle at the semilunate line. Midline defects measuring up to 10 cm superiorly, 18 cm centrally, and 8 cm inferiorly can be closed using separation of components. This technique is less effective in closing lateral defects, for which regional muscle and fascial flaps are usually better suited (rectus abdominis flap, internal oblique flap, external oblique flap). (See Schwartz 9th ed., p 1690.)

14. Optimal time for repair of a facial nerve injured during a surgical procedure is

A. Immediately

B. 2 weeks after injury

C. 4-6 weeks after injury

D. 3 months after injury

Answer: A

Traumatic injuries to the facial nerve without segmental nerve loss are best treated with primary end-to-end neurorrhaphy of the facial nerve stumps. The success of this repair depends on accurate approximation of nerve ends and achievement of a tension-free epineural repair with fine sutures, usually 8-0 nylon or finer. In segmental facial nerve loss due to trauma or oncologic resection, interpositional nerve grafts lead to the most successful reconstruction and may approach the results of primary repair. Grafting ideally is performed at the time of the injury rather than in delayed fashion. Donor nerves include the cervical plexus, great auricular nerve, and sural nerve. (See Schwartz 9thed., p 1681.)

15. The most likely diagnosis in the child shown in Fig. 45-3 is

A. Craniosynostosis

B. diGeorge syndrome

C. Treacher Collins syndrome

D. Pierre Robin syndrome

Answer: C

Treacher Collins syndrome, also known as mandibulofacial dysostosis, is a type of craniofacial clefting disorder representing bilateral 6-7-8 clefts. This autosomal dominant disorder with variable penetrance has the following manifestations: hypoplasia of the zygomas, asymmetry and hypoplasia of the mandible, ear anomalies, and colobomas of the lower eyelids. (See Schwartz 9th ed., p 1663.)

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FIG. 45-3.

16. The child shown in Fig. 45-4 is at increased risk for

A. Brain aneurysm

B. Hepatic hemangioma

C. Leptomeningeal vascular anomalies

D. Visceral aneurysm

Answer: C

This is a child with Sturge-Weber syndrome. Capillary malformations (CMs) are pink-red macular vascular stains that are present at birth and persist throughout life. These lesions tend to become more verrucous and darker throughout life. CMs are effectively treated with a pulsed-dye laser, and the results often are better with treatment in infancy and young childhood. Laser therapy often is repetitive and prolonged. CMs of the head and neck, historically called port-wine stains, may be associated with Sturge-Weber syndrome, which includes vascular involvement of the leptomeninges and ocular pathology. (See Schwartz 9th ed., p 1667, 68.)

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FIG. 45-4.

17. Immediate breast reconstruction (at the time of mastectomy) is associated with

A. Delay in starting chemotherapy

B. Decreased ability to detect an early recurrence

C. Slightly increased mortality

D. None of the above

Answer: D

A number of studies have shown that breast reconstruction, both immediate and delayed, does not impede standard oncologic treatment, does not delay detection of recurrent cancer, and does not change the overall mortality associated with the disease. (See Schwartz 9th ed., p 1682.)

18. Which of the following is a sign of venous occlusion in a free flap?

A. Increasing warmth

B. Increasing coolness

C. Increasing paleness

D. Increasing sluggishness of pinprick bleeding

Answer: A

Clinical flap monitoring continues after successful restoration of arterial inflow and venous outflow. The mainstay of postoperative free flap monitoring is clinical assessment (see Table 45-2), although supplementary instrument monitoring also can be helpful. (See Schwartz 9th ed., p 1657.)

TABLE 45-2 Clinical signs of arterial and venous compromise in a free flapa

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19. A child with more than three cutaneous hemangiomas should undergo

A. Abdominal ultrasound

B. CT of the abdomen

C. MRI of the brain

D. MRA of the abdominal vasculature

Answer: A

Hemangiomas are solitary in 80% of cases and multiple in 20%. In children with multiple (more than three) cutaneous hemangiomas, abdominal ultrasound is suggested to rule out hemangiomatosis with visceral involvement. (See Schwartz 9th ed., p 1667.)

20. The flap illustrated in Fig. 45-5 is a

A. Transposition flap

B. Bipedicle flap

C. Interpolation flap

D. Rotational flap

Answer: A

The flap illustrated is a rhomboid (Limberg) transposition flap. A transposition flap is rotated about a pivot point into an adjacent defect. A Z-plasty is a type of transposition flap in which two flaps are rotated, each into the donor site of the other, to achieve central limb lengthening. Another common transposition flap is the rhomboid (Limberg) flap. The bipedicle flap is comprised of two mirror-image transposition flaps that share their distal, undivided margin. Rotational flaps are similar to transpositional flaps but differ in that they are semicircular. Advancement flaps slide forward or backward along the flap’s long axis. Two common variants include the rectangular advancement flap and the V-Y advancement flap. Like transposition flaps, interpolation flaps rotate about a pivot point. Unlike transposition flaps, they are inset into defects near, but not adjacent, to the donor site. An example of an interpolation flap is the thenar flap for fingertip reconstruction. (See Schwartz 9th ed., p 1651.)

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FIG. 45-5. (Photographs reproduced with permission from M. Gimbel.)