Genital injuries are rare, but their impact can have devastating consequences to a patient’s physical and psychological health, impacting both sexual and reproductive function. The goal of surgical repair is to minimize further injury, allow micturition, prevent erectile dysfunction, preserve reproductive function, and provide adequate cosmesis. The mechanism of injury varies considerably from patient to patient, and operative repair should be individualized based on patient needs and the extent of injuries. Most genital injuries require wound irrigation, debridement of devitalized tissue, and a multilayered closure to prevent breakdown and fistula formation. Wound contamination and time to repair impacts the choice of reconstructive techniques. Genital injuries are rarely life threatening. Assess the patient and stabilize other major injuries before performing any genital reconstruction.
Genital Skin Loss
Treat genital skin wounds with a limited, initial debridement of devitalized tissue. Overaggressive surgical excision results in the removal of viable skin. Manage small lacerations and fresh, clean wounds immediately. Copiously irrigate contaminated wounds with normal saline. Remove any foreign material to reduce the risk of wound infection. Multiple trips to the operating room are often required for reassessment. Ischemic tissues will present with delayed necrosis and require excision. Continue with wet-to-dry dressings to complete debridement of full-thickness skin loss and help prepare the wound bed for skin grafting.
The majority of patients with lacerations or skin loss involving the penis and anterior scrotum are managed in the supine or frog-leg position. Place patients in the dorsal lithotomy for improved access to those with complete scrotal skin avulsion, wounds extending into the perineum, or injuries that may involve the urethra. If grafting is required, expose an adequate donor site for graft harvest. The anterolateral thigh is an ideal site because it provides enough surface area for genital skin grafting, can be easily accessed in either the supine or lithotomy position, and is generally concealed even in summer clothing. If thigh skin is not available, use alternatives such as the abdomen or back.
Laceration and Avulsion Injuries
Cautiously debride injured areas of the scrotum and penis and irrigate with normal saline. Because of the rich vascular supply of the genitals, even large lacerations, if uncontaminated, can be closed primarily. Close deeper lacerations involving the dartos layer with 3-0 polyglactic acid suture followed by skin closure with 4-0 chromic cat gut or nylon suture. Leave a drain if there are concerns about contamination ( Fig. 128.1 ). Scrotal skin loss of up to 50% can be closed primarily because of the inherent elastic properties of the remaining skin. Circumferential, full-thickness loss of the penile shaft skin results in lymphatic disruption and subsequent edema of any remaining distal penile skin. Thus, if proximal shaft skin is circumferentially absent, remove skin distal to the injury site at the time of debridement. Perform this in anticipation of future grafting using a single, uniform skin graft for the entire shaft.
Chemical, thermal, and electrical burns require specific interventions based on the mechanism of injury. Treat thermal burns with a 1% silver sulfadiazine cream. Await separation of eschar from healthy tissue before repair. Perform debridement of any nonviable tissue and continue with dressing changes until the wound is clean. The management of chemical burns requires initial decontamination. If a powder, gently brush off the offending agent. Strip off any contaminated clothing. Perform low-pressure, warm, water irrigation to dilute the offending chemical. Take care not to spread the irrigant to noncontaminated skin. Apply litmus paper to measure the pH of the affected area to assure removal and neutralization of the chemical agent. Certain chemicals require special treatment. If lye is present, brush it off before irrigation because it reacts with water to create a strong alkali. Elemental metals such as sodium, lithium, and potassium react with water, creating an exothermic reaction. Cover elemental metals with mineral oil and manually remove the metallic fragments. Treat hydrofluoric acid with initial irrigation. Topical calcium gluconate or magnesium is required to neutralize the fluoride ion, which can penetrate tissue. Fluoride binds with magnesium and calcium, causing electrolyte abnormalities, and may lead to cardiac arrest. Manually wipe away phenols, which are not soluble in water, and treat with topical 50% polyethylene glycol. The extent of electrical burns is difficult to determine because of dissemination of current into the surrounding tissues. Do not undertake debridement until the demarcation between viable and nonviable tissue has been delineated.
Treat wounds from animal bites with tetanus toxoid and appropriate broad-spectrum antibiotics such as cephalexin or doxycycline. Pasteurella multocida is a risk factor in both dog and cat bites. If Pasteurella resistance is suspected, administer penicillin V. Avoid primary closure in human bites because they are more prone to infectious complications. Despite different bacterial flora, human bites can be treated with similar antibiotic regimens.
Genital Skin Grafting
Multiple techniques exist for the harvest and grafting of genital skin loss. Split-thickness grafts involve the epidermis and a partial thickness layer of the dermis. They have the clinical benefit of fast donor site reepithelialization and generally good take at the recipient site. However, they suffer from increased contraction. The stability of a split-thickness graft depends on the thickness of the dermal layer, and contraction is reduced by harvesting a thick, split-thickness graft. Grafts are defined as thin (0.15–0.3 mm), intermediate (0.3–0.45 mm), and thick (0.45–0.6 mm). Split-thickness grafts can be harvested and applied as single sheet or meshed grafts. Meshing creates a series of perforations in the graft, allowing expansion of the graft size to cover more surface area. The spaces between skin bridges will reepithelialize, but this comes at the cost of increased scaring. Meshed grafts have better take at the recipient site because of drainage of fluid through the perforations, resulting in lower rates of hematoma formation and infection under the graft.
Full-thickness grafts use the epidermis and the complete layer of dermis. The thicker layer of dermis minimizes graft contraction and improves functionality. In addition, they have the benefit of better texture and native skin color. The increased thickness of full-thickness grafts results in delayed graft revascularization and decreased rates of graft take. Full-thickness grafts are more prone to fluid accumulation beneath the graft (blebbing) and are subject to higher rates of infection. Graft donor sites are of limited availability because of both size and location. In addition, donor sites require primary closure or coverage.
Skin Grafting of the Penis
Preparation of the Penis
Place the patient in the supine or frog-leg position. If the penis has been managed with prolonged dressing changes, excise any residual granulation tissue. The penis can become trapped by adhesions from surrounding skin at the base. Free the penile shaft from the surrounding structures using Metzenbaum scissors. Anchor the scrotal and pubic skin at the base of the penile shaft with buried 4-0 polyglactic acid suture to prevent future penile retraction, graft loss, and buried penis. The sutures should be placed at the level of the surrounding skin. Avoid anchoring too proximal on the penile shaft, below the skin level, because this will create a postoperative cleft that is difficult for the patient to clean. Remove any residual skin up to the corona to prevent lymphedema in cases of circumferential injuries. After the penile shaft is prepared for grafting, select your graft technique.
Full-Thickness Skin Grafts
Full-thickness grafts are rarely used for a completely denuded penis because of a lack of large donor sites. They are best suited for smaller areas of penile skin loss. Full-thickness grafts have an innate resistance to friction, which makes them a reasonable option for reconstruction of the penis. Donor sites include, but are not limited to, the posterior auricular region, inguinal fold, infraabdominal fold, buttock fold, inner arm, and antecubital area of the elbow.
Measure the coverage required at the recipient site and mark out a corresponding area on the donor site. The harvested graft should be similar size to the wound because of lack of graft contraction. Incise the tissue with a scalpel. Elevate the graft off the underlying fat with Metzenbaum scissors. Close the donor site using 3-0 polyglactic acid to reapproximate the subcutaneous tissue and 3-0 nylon to close the skin. Remove excess fat from the graft’s underside and fenestrate with a scalpel. Transfer the graft to the recipient site.
Split-Thickness Skin Grafts
Split-thickness grafts to the penis have increased graft take but suffer higher rates of contraction. They are ideally suited for circumferential, penile skin loss. Obtain a split-thickness skin with a wide (12.5-cm) pneumatic dermatome. Donor sites include the inner or outer thigh and lower abdominal wall. The thigh is the ideal donor site with thicker skin, allowing for more rapid reepithelialization. Shave and prep the leg and cover in a sterile stocking for intraoperative manipulation. Harvest a split-thickness skin graft 0.45 mm thick, 12.5 cm wide, and 15 cm long. Place the split-thickness skin graft over the penile shaft. The width of the graft will cover the length of the penis. Wrap the long portion of the graft around the penis circumferentially. Overlap the graft on the ventral aspect of the penis. Trim the excess graft in a zigzag fashion to prevent chordee development associated with a linear suture line.
Unexpanded, Split-Thickness Skin Grafts
Unmeshed grafts have the disadvantage of fluid accumulation beneath the graft (blebbing), resulting in reduced graft take. Meshed grafts prevent blebbing through drainage of fluid from under the graft. Contraction is associated with higher meshing ratios, such as 1 : 1.5. The authors have had good results using a meshing ratio of 1 : 1 and unexpanded (unstretched) graft placement on the penis. Obtain a split-thickness skin graft as described earlier. Mesh the graft in a 1 : 1 ratio. Place the mesh graft on the penis as described earlier and orient the meshing transversely. Prepare the ventral Z-plasty as described earlier ( Fig. 128.2 ).