Plastic surgery

PART VIII

HAND

CHAPTER 88  MANAGEMENT OF THE BURNED HAND

WILLIAM C. PEDERSON

Burns of the hand remain problematic. Although more attention to the preservation of hand function has been directed to patients with severe burns, the hands are clearly less important than saving the patient’s life. This leads to initial neglect of the hands, and the resulting hand function is often poor. In addition, the hand may be difficult to reconstruct, since the damage involves not only the skin but also the tendons, joints, and bones. Once scar contracture has occurred, restoration of motion can be nearly impossible (Figure 88.1). Initial management is therefore paramount to allow later reconstruction of a functional hand.1 This chapter addresses early management, but concentrates on later reconstruction because this is where the plastic surgeon is most often involved (Chapter 16).

EARLY MANAGEMENT

The hands are frequently involved in thermal injuries, whether when accidentally grasping a hot object or protecting oneself from flames or steam coming from an automobile radiator (Chapter 15). The skin on the hands is relatively thick, and substantial heat is required to produce a full-thickness burn. Burns are generally classified by depth. First-degree burns are superficial and involve the epidermal layer. An example of this type of burn is sunburn, and these burns will heal spontaneously in a period of 2 to 3 days without scarring. Second-degree burns are intermediate in depth, involving the epidermis and a portion of the dermal layer. These types of burns are divided into superficial partial-thickness injuries and deep partial-thickness injuries. Superficial second-degree burns destroy the epidermis and the upper layer of the dermis, demonstrate blistering of the skin, and will heal spontaneously in 7 to 10 days with minimal scarring. Deep second-degree burns destroy the epidermis and a deeper layer of the dermis. These burns heal slowly and develop significant scars. Both types of second-degree burns are painful. Third-degree burns (or “full-thickness burns”) involve all layers of the epidermis and dermis and destroy all germinal elements of the skin. In these injuries, the skin looks like leather and is anesthetic. These third-degree burns will require some type of coverage because there is no capacity for the skin to re-epithelialize. Fourth-degree burns involve deeper structures, and these may even damage the bone. These types of burns are most common with electrical injuries.

Recognition of a first-degree burn is usually easy, but the difficulty comes in patients with deeper second-degree and third-degree burns. While proper management is predicated at least partially on an accurate evaluation of burn depth, this can be quite difficult in the early stages. Burns that will heal within 2 weeks should be allowed to do so in most instances, but deeper burns are generally best managed by early excision and grafting.2 Superficial second-degree burns generally are blistered. When the blisters are debrided, there is usually pink, moist dermal tissue underneath. Deeper second-degree burns will often have a more whitish and dry appearance (that of the deeper dermis) once blisters are debrided (Figure 88.2).

The initial management of hand burns involves gently cleaning the burns of foreign material and loose skin. I prefer to deflate intact blisters with an 18G needle allowing the epidermis to lie back down on the burn when possible. The status of tetanus immunization should be ascertained and the patient given a booster if immunizations are not up to date. Once the burns are cleaned, an attempt should be made to ascertain the depth of the injuries. Most second-degree burns should be allowed to heal, but deeper second-degree burns and third-degree injuries should be considered for early excision and grafting as noted above. With large burns this may not be possible, but with smaller burns in the hand, early excision of deeper burn injuries and grafting can lead to the best functional results.2Once the burns are cleansed, they are covered with an antibiotic cream and a light dressing. Most outpatients receive silver sulfadiazine cream, but any type of antibiotic ointment (gentamicin or mupirocin) is probably adequate for smaller burns. Traditional wisdom has been to provide a short course of oral antibiotics as well, but there are no data to support this unless there is clinical evidence of infection. Hand burns should be splinted in a functional position, with the wrist extended, the metacarpophalangeal joints in flexion, and the interphalangeal joints in extension. Maintaining motion of the hand and fingers is important, however, and thus the splint should be removed frequently and the fingers moved both actively and passively.3 I prefer to involve a physical therapist early on in the care of hand burns, as they can aid in daily wound care and also make sure that the fingers are kept mobile.

FIGURE 88.1. Hand of patient with 60% total body surface area (TBSA) burn, managed in a burn unit. A. Palmar view. There is no motion in the fingers and poor sensibility. B. Dorsal view.

FIGURE 88.2. Flame burn of hand and forearm. A. Before debridement. B. After debridement of blisters and nonviable skin. Note areas proximal to wrist and on forearm that are whitish. These areas are deep second-degree burns while the surrounding pink areas are more superficial.

Superficial burns to the hand should usually heal within 2 weeks, and the fingers must be kept moving during this period. One alternative to dressings is to cover the hand in antibiotic cream and place it in either a surgical glove or one of the various available gloves designed for the management of burns.4 This allows motion of the hand while keeping the burns moist and in contact with the antibiotic. This treatment is continued until the burn is healed. If the burns do not heal within 2 weeks, grafting will probably be necessary (Figure 88.3).

SKIN GRAFTING

Although most burns are covered with split-thickness skin grafts, burns on the hand are frequently better managed with full-thickness grafts. Specifically, burns of the digits (particularly the pulps) and of the web spaces will often be more functional if covered with full-thickness skin grafts, and if possible, consideration should be given to doing this early (Figure 88.4). The dorsal hand can be covered with split-thickness skin grafts without difficulty, assuming that the tendons have not lost their covering epitenon. These grafts may be meshed with little functional difficulty, but the cosmetic results are usually superior if sheet grafts of split-thickness skin are utilized (Figure 88.5). In deeper burns, one of the dermal substitutes may be used to allow for thicker and potentially more pliable cover.5 The problem with these products is the need for them to “become vascularized” prior to placing a split-thickness graft. This requires immobilization and prolongs the total period of immobilization because the hand requires immobilization once the skin graft is placed. For this reason, I am not sure they provide an advantage.6

FIGURE 88.3. Dorsal forearm 3 weeks after steam burn. Note that the hand and forearm have healed, and the proximal forearm (which in hindsight was full thickness) is now granulating. This area required skin grafting.

FIGURE 88.4. Child with flame burn. A. Eighteen-month-old after falling in camp fire. There are full-thickness burns of the pulps of the index, middle, and ring fingers which were debrided and grafted with full-thickness skin from the tips of three toes. B. Same child at 5 years of age.

FIGURE 88.5. Hand of patient status post skin grafting of dorsal hand with sheet graft of split-thickness skin. Note the quality and excellent cosmetic aspect of graft.

Intermediate and deep burns of the hand require excision and grafting that is performed as early as possible. To preclude the development of stiffness and joint contractures,4 the technique of “tangential excision” is useful in the dorsal hand for excising the burn and avoiding removal of viable tissue. The burn is excised in thin layers using either a Weck blade (a straight razor on a handle) or one of the larger knives intended for this purpose (Humby knife, Blair-Brown knife, etc.). The blade is fitted with a guard to control the depth of excision. Thin layers are excised in sequence until the tissue bleeds. Use of this technique prevents the removal of underlying viable tissue but allows removal of all nonviable tissue from the effects of the burn. If the area of excision is relatively small and adequate hemostasis can be obtained, the area should be covered with split-thickness skin at the time of excision. In the case of larger areas of excision (i.e., the entire forearm), it may be better to obtain hemostasis of the main bleeding points and wrap the area to allow for complete hemostasis. In the case of an infected wound, grafting should be delayed until control of the wound is obtained.

Split-thickness skin grafts are usually treated postoperatively with a closed dressing, but in the hand it may be efficacious to manage these in an “open” fashion. The hand can be placed in a splint and dorsal grafts left open so that they can be observed. This is particularly useful in the placement of sheet grafts to the dorsal hand. If subgraft fluid collects, it can be removed by “rolling” the fluid to the edge of the graft (if it is near the periphery) or by releasing the area of fluid collection with an 18G needle. These grafts have adequate “take” to begin motion in 2 to 3 weeks. Splinting these patients in the “functional position” (interphalangeal joints extended and metacarpophalangeal joints flexed) until the graft has taken is required to help prevent further joint contracture in an undesirable position. Splinting in the postoperative period while motion is being re-established is important as well and is usually done at night or during periods of inactivity. Failure to properly splint these patients can lead to severe sequela of scarring as seen in Figure 88.1.

POST-BURN RECONSTRUCTION

The final functional result in hand burns remains problematic due to non-grafted burns, contracture under split-thickness skin grafts, and contracture of joints from disuse. Better initial care with appropriate wound care, grafting, postoperative splinting, and physical therapy has decreased these problems. Despite this, particularly in patients with large total body surface area burns, burn scar contracture of the hands continues to pose difficulties.7 Skin contracture can lead to joint stiffness and degeneration, with the potential need for amputation of the involved digit(s).

Palmar and volar digital contracture can usually be managed with incision/excision of the scar and placement of a full-thickness skin graft.8 Full-thickness grafts are preferred in this setting due to their decreased contracture compared with split-thickness grafts. Donor sites include any non-burned skin, but I prefer to use skin from the arm or from the iliac crest. These areas provide hairless skin in most people and the color match from the crest area is not nearly as poor as darker grafts harvested from the groin. The area of contracture is released with simple incision of the scarred area and traction is applied to the involved finger(s) until length is restored. An appropriately sized full-thickness graft is placed, held in place with a tie-over bolster for 3 weeks, and that part of the hand is splinted during this period. Loss of all or even a portion of the graft can lead to re-contracture, and thus great care is taken to maximize graft take. In contracture of the palm, flap coverage may offer the best option (Figure 88.6).

Contracture of the first web space is common after burn injuries and leads to significant problems with hand function. Although release with a full-thickness grafting can be successful, most patients are best treated with a flap placed in the web space to prevent re-contracture. Options include the pedicled radial forearm and groin flaps and the lateral arm free flap.9

Burns to the dorsal proximal interphalangeal (PIP) joints present unique challenges. Skin breakdown and loss of the extensor tendon mechanism leads to post-burn boutonniere deformities that are difficult to manage. The skin over the dorsal PIP joints is thin to begin with, and after burns, is even more fragile. It is difficult to operate on the joint through this poor skin cover, and many patients require full-thickness skin grafting or flap coverage prior to addressing the boutonniere deformity. Multiple procedures have been proposed, including suturing of lateral bands together and tendon grafting but the results of all of these procedures are unpredictable. Arthrodesis of the PIP joint in a functional position (in the 40° to 50° flexion range) is often the most appropriate management.4 The bony shortening required for arthrodesis allows skin coverage to be managed without too much difficulty.

Dorsal web space contracture between the fingers (in the second to fourth web spaces) is also common after burns, manifested as dorsal webs between the fingers. This may or may not involve the natural web between the involved fingers. There have been various approaches proposed, but most surgeons prefer z-plasty release. Dorsal webbing is usually well released with the four flap opposing z-plasty or “jumping man” z-plasty. Failing this, the area of scarring can be released and small full-thickness skin grafts placed, but take of grafts in this area can be problematic. Occasionally, burns are so severe that a partial syndactyly develops. Release of this condition requires the use of both local flaps (for the web space and adjacent fingers) and full-thickness grafts. Release of burn-scar syndactyly is not much different from release of congenital syndactyly in its planning and execution.

The management of digital amputations is similar to other amputations. If the majority of fingers are present, no treatment may be necessary. In the case of severe burns of both hands with loss of multiple digits, however, reconstruction of the thumb or digits may be appropriate. Toe transfer may necessitate prior coverage of the hand with a flap. I prefer to utilize a pedicled groin flap in this case, which improves coverage without the need for microvascular anastomosis (and leaves all available vessels for the later toe transfer).

Loss of the thumb can be devastating to hand function and is managed with either pollicization of a remaining finger or toe transfer.10 A functional thumb can be made from a shortened index finger, as long as motion and length would allow for opposition to the remaining fingers. Failing this, microvascular toe transfer may be necessary. Likewise in the case of loss of multiple digits, transfer of the second toe(s) can restore digital function (Figure 88.7).

FIGURE 88.6. Palmar contracture. A. Severe contracture of right palm. B. After release and placement of thin lateral arm free flap. C. Six months after release and free flap placement.

Long-term management involves continuation of therapy until scarring is mature and contracture is complete. This can easily take 6 months to 1 year. Massage and motion are the mainstays of therapy. Compression gloves can be helpful in decreasing scarring, but must be well fitting to prevent skin breakdown and further problems. Patients frequently do not wear their garments due to pain and functional limitations.11 Close follow-up is warranted after initial care of the burn patient to mitigate the effects of ongoing scar contracture.

FIGURE 88.7. Double second toe transfer. A. Fireman who lost all fingers on his right hand from burns. He is seen 6 months after double second toe transfer. He required a pedicled groin flap as a first stage to improve coverage. B. Flexion of transferred toes. The patient has returned to full duty as a fire fighter.

References

1.  Kowalske K. Outcome assessment after hand burns. Hand Clin. 2009;25: 557-561.

2.  Omar MT, Hassan AA. Evaluation of hand function after early excision and skin grafting of burns versus delayed skin grafting: a randomized clinical trial. Burns. 2011;37:707-713.

3.  Sterling J, Gibran NS, Klein MB. Acute management of hand burns. Hand Clin. 2009;25:453-459.

4.  Germann G, Weigel G. The burned hand. In: Wolfe SW, Hotchkiss RN, Pederson WC, Kozin SH, eds. Green’s Operative Hand Surgery, 6th ed. Philadelphia, PA: Elsevier; 2011,2089-2120.

5.  Weigert R, Choughri H, Casoli V. Management of severe hand wounds with Integra(R) dermal regeneration template. J Hand Surg Eur. 2011; 36:185-193.

6.  Haslik W, Kamolz LP, Lumenta DB, Hladik M, Beck H, Frey M. The treatment of deep dermal hand burns: how do we achieve better results? Should we use allogeneic keratinocytes or skin grafts? Burns. 2010; 36:329-334.

7.  Kreymerman PA, Andres LA, Lucas HD, Silverman AL, Smith AA. Reconstruction of the burned hand. Plast Reconstr Surg. 2011;127: 752-759.

8.  Grishkevich VM. First web space post-burn contracture types: contracture elimination methods. Burns. 2011;37:338-347.

9.  Megerle K, Sauerbier M, Germann G. The evolution of the pedicled radial forearm flap. Hand (N. Y.). 2009;37-42.

10.  Kurtzman LC, Stern PJ, Yakuboff KP. Reconstruction of the burned thumb. Hand Clin. 1992;8:107-119.

11.  Ripper S, Renneberg B, Landmann C, Weigel G, Germann G. Adherence to pressure garment therapy in adult burn patients. Burns. 2009;35:657-664.