Bilateral Dorsal Foot Scar Contracture Release with Split-Thickness Skin Grafts from the Anterior Thigh

Abstract

Burn scar contracture is a common sequela following burn injuries of the dorsal foot. As many as 11.9% of pediatric patients with burns to the ankle develop contractures. Contracture of the dorsal foot causes metatarsophalangeal joint hyperextension and interphalangeal joint hyperextension. This impairment affects ambulation and daily activities such as wearing shoes. These issues only intensify over time as a child grows. Here we present the case of a young boy who suffered a 32% total body surface area flame burn to his lower back, bilateral buttocks, legs, and feet. This patient had previously undergone a bilateral contracture release of the dorsum of the foot. Because contractures recurred, we performed a bilateral dorsal foot scar contracture release using a split-thickness 1:1 meshed skin graft harvested from the anterior left thigh. We outline the natural history, key intraoperative techniques, and postoperative wound management.

Case Overview

Background

The incidence of contracture in the pediatric population is 28%, and 11.9% of pediatric patients with burns to the ankle develop contractures.¹ The incidence of pediatric mortality from burns has greatly decreased to 1% to 2%. Given this increased survival, especially for large burns, there is a greater emphasis on rehabilitation and reconstruction so that patients can return to society. Contractures of the dorsum of the foot cause shortening of tendons and muscle groups across the metatarsophalangeal (MTP) and talocrural joint resulting in a fixed hyperextended position.^2, 3 While the foot dorsum is a small area of total burn surface area, contractures at this anatomical location can cause debilitating consequences. These patients are left with impaired ambulation, difficulty in executing daily activities such as finding adequate footwear, and poor aesthetic concerns. These issues only intensify as the child grows, further contracting the inelastic scar tissue.⁴ Rehabilitation therapy is the first line of defense against contractures, consisting of daily motion exercises and splinting in antideformity positions.⁵ Contractures are worse for patients who do not receive adequate burn care and rehabilitation.⁶ For bed-ridden patients, adequate rehabilitation may not be possible. Burn contractures are a powerful and unrelenting force that may occur even in spite of early rehabilitation and scar management.

Release and grafting is a standard method for correction of large contractures.⁷ This procedure returns full range of motion to the joints of the ankle and toes.

Focused History of the Patient

The patient presented in this case is a 4-year-old male, who we cared for after sustaining a flame burn while playing hide and seek a year and eight months prior to the current surgery. Affected total body surface area was 32%, including his lower back, bilateral buttocks, legs, and feet. The patient did well from his initial early grafting, but developed contractures at the ankle joint for which he previously underwent release and grafting. The procedure detailed in the present article sought to address the recurrent dorsal foot contracture on both feet via release and grafting. His American Society of Anaesthesiologist score prior to surgery was I.

Physical Exam

Three days prior to the procedure, we examined the surgical site for range of motion and identified areas of maximal tension. Physical exam revealed a healthy young boy who ambulated to his presurgery appointment accompanied by his parents. His wounds were fully closed with visible hypertrophic scarring and dyspigmentation at previously grafted surgical sites.

Natural History

Burn contractures are more likely to result from, and tend to be more severe in the context of full-thickness wounds, wounds in areas of elastic skin. Development of contractures correlate with prolonged time to wound closure and patient immobility. When left untreated, contractures cause capsular contraction, shortening of the tendon, and shortening of the muscle groups across the joint. In contractures on the dorsum of the foot, the talocrural and MTP joints hyperextend affecting the patient’s gait, daily activities, and appearance.

Options for Treatment

There are a range of surgical interventions to relieve burn contracture, including local rotating skin flaps, release and grafting, tissue expanders, or free flap reconstruction.⁸ The choice of method depends on a variety of factors such as the size of the contracture, the site of the contracture, availability of donor site skin, the experience of the surgeon, and the preference of the patient. For large contractures over a joint, release and grafting is the preferred method.

With a release and grafting procedure, either a full-thickness or split-thickness graft may be used. In growing children with large defects, a split-thickness graft is more suitable. Using a split-thickness graft provides the advantage of requiring less blood supply, less burden of pain at the donor site, and reduced likelihood of skin sloughing.

Kirschner wires (K-wires) may be used for stabilization of the joint during and following the procedure. They are especially useful when the incision site is more distal to the dorsum of the foot. However, in active children, K-wires complicate postoperative care by causing more pain and less mobility.

Another consideration for treatment is whether to delay the procedure. As the child grows, the tightening of the contracture would interfere with the neighboring tissue, causing irreversible damage to the joint muscle groups and tendons. Early surgical intervention provides the best opportunity to return full range of movement to the joints for the best functional result.

Rationale for Treatment

Given that the patient had again developed a large contracture to the dorsum of the foot, release and split-thickness grafting was the preferred corrective option.⁷ We chose to make the line of incision more proximal to the talocrural joint in order to avoid the need for K-wire insertion in the MTP joint. By not using K-wire insertion, we hoped to reduce postoperative pain and ease wound care for the parents.

Special Considerations

The use of a split-thickness graft and early surgical intervention is best for a growing child of 4 years of age. For the adult population, the use of K-wires, full-thickness grafts, and delayed surgical intervention may be warranted.

Discussion

We presented the case of a 4 year-old boy with burn contractures of the dorsum of the foot. He underwent a bilateral release and split-thickness 1:1 meshed skin graft from the anterior thigh without any complications. The final result demonstrated complete release of the contracture over both feet, returning the feet and toes to a neutral position.

The line of incision was chosen by manipulating the foot into a plantar-flexed position to visualize the areas of maximal tension. We opted to incise more proximal to the talocrural joint to avoid the need for inserting K-wires in the toes to minimize movement at the wound site. For a young active boy, the use of K-wires would cause more postoperative pain and would complicate postoperative wound care for the caregivers.

Diluted epinephrine was injected at the site of release to provide hemostasis to prevent blood loss. We opted to release a larger area than originally anticipated in the left foot. Because epinephrine was not injected in the peripheral area, some bleeding occurred. This peripheral bleeding was controlled by spot electrocautery of the microvasculature.

Release was initiated using gentle superficial cuts to avoid lacerating the underlying subcutaneous tissue and blood vessels. Skin edges were elevated using double hooks to create tension to ease the excision of scar tissue. A scalpel is not always needed, and a swiping-pushing motion technique can be used to make back cuts to separate scar tissue underlying the skin at the edges of the released area. We were careful not to cut into the subcutaneous fat. The scar tissue and underlying fascia were visibly distinct.

The bilateral release areas were measured 10 x 8 cm on the left foot and 7 x 12 cm on the right foot. These areas were combined to estimate the donor area to harvest. Additional area was added to the donor harvesting area to account for the need to cover the edge contours of the surgical wound bed. We were mindful not to harvest too close to the knee so as not to create pain and diminish range of motion in the knee. The donor site area was prepped with ample injectable epinephrine into the subcutaneous layer. Again, diluted epinephrine provided hemostasis. One added advantage of using injected epinephrine is that the volume of the solution creates a more flat surface to harvest donor skin in an otherwise circular anatomical area. When the dermatome is used, a uniform split-thickness graft can be harvested. Of note, we tightened the dermatome screws and checked that the dermatome blade distance is uniform by passing a scalpel blade through the gap.

We opted for a split-thickness 1:1 graft rather than a full-thickness graft for several reasons, including less morbidity of the donor site. Full-thickness grafts require ample perfusion to the underlying dermis, especially in the early phases of graft-take. With full-thickness grafts, the epidermis may slough off, which could be distressing for the child and family. Finally, because he was a growing child, future releases may be necessary; therefore, a split-thickness graft was preferred.

The importance of wound dressings to ensure the success of graft-take in a large defect is not to be underestimated because it provides many functions. The purpose of the dressing is not only protection. Adaptic Kerlix bolster and gauze filled the trough created by the release, pressing the graft into the wound bed, including at the edges. We placed 2-0 silk sutures evenly around the graft site. These sutures were tied to hold and compress the dressing into the wound bed. Fenestrations were cut into the Adaptic bolster to allow for topical medications to reach the wound bed. A red rubber catheter, with holes cut into the distal end, was attached to the outside of the dressing to ease the irrigation of Sulfamylon solution over the bandages.

Traditionally, dressings are left on for a week. We left the dressing on for two weeks. This provided further time for healing; a bulky dressing makes movement harder for the child who would naturally want to be active.

The total procedure time was three hours and forty-five minutes. The patient awakened uneventfully from the procedure in stable condition. The estimated blood loss was 20 ml. The tension caused by the contracture was released, as evidenced by the laxity present on the overlying skin, especially on the distal part of the foot. The patient stayed overnight and returned at two weeks for stent takedown. We anticipate that this child may need additional procedures in the future for contracture release or laser surgery to address hypertrophic scarring.

Equipment

Special pieces of equipment used in this procedure included double hooks, Xeroform™ Telfa^™ dry sterile dressing Kerlix^™ wrap, Cuticerin Adaptic^™ bolster, non-absorbable 2-0 silks, size 8-F red soft catheter, and stabilizing rehabilitation boots.

Disclosures

The authors have no disclosures to report.

Statement of Consent

The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.