The Use of Acellular Dermal Matrix in Treatment of Mitten Hand in Epidermolysis Bullosa Patients

Dear Sir, Epidermolysis Bullosa (EB) is a group of rare disorders, in which patients frequently present with fragile skin and mucosal surfaces that blister following minor trauma [1]. Hand deformities include web space adduction contractures, pseudo-syndactyly, and flexion contractures of the joints, known altogether as the mitten-hand deformity [2]. Reconstruction of the defects created by releasing of the pseudo-syndactylys or just the flexion contractures of the hands requires use of skin grafts; which make the surgical treatment troublesome for two main reasons: the donor skin graft areas become potential full thickness non-healing regions, and the skin graft harvested will not be a healthy skin, with a defective dermoepidermal structure that will eventually result in recurrence of the syndactyly with any minimal trauma. We present here an 8-year-old female who referred to our clinic for bilateral pseudo-syndactylys of the hands. The medical history revealed diagnosed recessive dystrophic EB that has been managed meanwhile only with palliative topical medication. Physical examination showed multiple bullae and vesicles that were spread generally all over the body with the hands and the legs involved most severely. The left hand revealed adduction contracture of the first web space, incomplete syndactyly of all the web spaces and flexion contractures in all the digits, with the fingernails absent. The right hand revealed incomplete syndactylys of all the webs, with joint contractures of the thumb MCP and IP as well as flexion contractures in all fingers. The surgical treatment was planned for the non-dominant left hand first, which required definite use of skin grafts, for coverage of full thickness skin defects created by the contracture release. The possibility of unsuccessful graft take was discussed with the patient in addition to the possibility of non-healing graft donor sites. The alternative use of acellular dermal matrix without further skin grafting was suggested and the treatment plan consisting of AlloDerm-GBR one-step repair was presented and accepted by the patient. The patient was operated under general anesthesia without application of a tourniquet to prevent trauma. The syndactylys and contractures were released full-thickness and the defects were covered with two pieces of 0.5–0.9 mm thickness sheets of AlloDerm GBR. (Figure 1a) No autologous skin grafts were used. The hands were kept in the appropriate splinted position for 15 days and the dressing was renewed every 3 days. An atraumatic night splint was then used for 2 months to prevent recurrence. The postoperative results revealed epithelization onto the AlloDerm grafts within 2 weeks with the exception of a few areas that were epithelized in 3 weeks (Fig. 1b). Fig. 1 a Intraoperative view showing release of the contractures and application of Alloderm in areas of skin defect and b 60 days postoperatively showing the Allograft take The defects created while releasing the hand pseudo-syndactylys and contractures require use of split-thickness or full-thickness skin grafts, which may not always be possible in these patients because of donor-site morbidity or availability [3, 4]. The use of acellular dermal allograft in EB patients not only makes the need for autologous skin graft redundant, but can also be of great assistance in epithelization. This is of major importance in these patients for which the autologous graft donor site can become a reconstructive challenge on its own, as it is in our case with bilateral hand and body involvement. Recurrence usually occurs within 2 to 5 years in patients with EB. Meticulous skin care and the use of well-fitted splints are essential in the treatment plan of these patients. The transfer of a dermal support, throughout a healthy tissue creating a “thick” new dermis via the acellular dermal matrix can hence possibly prevent recurrence of the pseudo-syndactyly of the hand in the long term. We believe the use of acellular dermal allograft in dystrophic EB patients with hand deformities should be included in the routine surgical treatment protocol of EB, especially in cases with bilateral involvement.