Addressing A Gangrenous Fifth Digit
In the case presented here, the patient presented each time with critical limb ischemia and dry gangrene of the fifth digit. Each time, the patient underwent appropriate procedures for revascularization prior to the partial foot amputation. For the left foot, the patient had two surgical interventions, negative pressure wound therapy and the use of advanced skin substitutes for a total of six months prior to complete healing.
Although a formal cost analysis did not occur, we can assume the total cost of care for the left foot was several thousands of dollars in addition to the patient’s personal expense for travel and the emotional expense in dealing with a chronic wound. Additionally, the resultant scar was prone to pressure and callus formation, causing it to be at risk for future breakdown.
Contrast this with the treatment of the patient’s right foot. Surgeons employed a partial fifth ray resection and fillet flap of the fourth toe to allow for tension free closure of the amputation site as the index procedure on the foot. Although the patient lost the fourth toe, he was fully healed with minimal loss of function and was ambulatory without restriction at six weeks postoperatively.
Minimum ray resection allowed for complete removal of the necrotic digit, facilitated reduced tension on the resultant soft tissue defect and preserved vascularity to the soft tissue envelope due to the limited dissection and disruption of the intermetatarsal space in which the vessels travel.1 Use of the fillet flap of the fourth toe provided durable and readily available coverage of the amputation site. This did not result in excess “bulk” at the distal foot, covered the remaining bone and minimized the potential for prolonged healing and further amputation.2,3
What The Literature Reveals
Küntscher and colleagues reported on 11 patients and cases in which surgeons utilized fillet of toe flaps to cover defects secondary to trauma, tumor excision, ulceration, osteomyelitis, gangrene and burns.2 With one flap, there was total necrosis secondary to progressive gangrene, which necessitated a more proximal amputation. In another case, the authors noted partial necrosis with a flap and subsequent wound healing via secondary intention.2 Use of fillet of toe flaps resulted in successful healing in the remaining nine patients.
Roukis reported on 13 patients who had 17 ray resections utilizing the minimum incision technique.1,3,4 Seven patients were without complications, one patient had delayed healing due to non-adherence, four patients underwent more proximal amputation due to progressive gangrene and there was one death.1
The use of minimum incision ray resections and fillet of toe flaps can result in expeditious limb salvage, which is paramount in the case of limb salvage secondary to critical limb ischemia. These techniques allow for rapid primary closure and limit disruption of the soft tissues and vascularity of the foot. Furthermore, these techniques limit the potential for compromised skin and soft tissue should an additional procedure be necessary, and can limit the loss of function of the residual foot. The primary factor resulting in failure of these procedures appears to be compromised circulation to the foot.1,2 One should take this into consideration prior to selection of the definitive surgical procedure when treating critical limb ischemia.
Dr. Schade is the Chief of the Limb Preservation Service and Director of the Complex Lower Extremity Surgery and Research Fellowship at Madigan Healthcare System in Tacoma, Wash. She is an Associate of the American College of Foot and Ankle Surgeons.