Functional reconstruction of the diabetic foot

Abstract

The diabetic triad of neuropathy, vasculopathy, and foot deformity can be surgically challenging to the reconstructive surgeon. Soft tissue deficits must be closed to protect underlying structures from infection and to provide a stable environment for healing. It is critical to have adequate blood flow and to debride the wound to clean healthy tissue before considering reconstruction. Surgical options commonly used include healing by secondary intention, local flap closure, skin grafts, pedicled flaps, and free tissue transfer. Despite a surgeon's best operative efforts, these strategies may fail perioperatively due to postoperative shear forces created by premature joint motion and/or pressure (either weight bearing or decubitus). In the properly selected patient population, external fixators serve as an indispensable adjunct to wound healing in the Charcot foot by providing temporary but reliable offloading and/or immobilization of joints. Using a team approach is critical to the success of diabetic limb reconstruction.

Keywords: Diabetes; lower-extremity flaps; neuropathy; reconstructive surgery.

Figure 1

(A) A 29-year-old, obese diabetic patient had bilateral lateral plantar metatarsal ulcers secondary to equinovarus deformity. Both the gastrocnemius and soleus portions of the Achilles' tendon were tight. (B) The left Achilles' tendon was released percutaneously, and the left foot healed in 6 weeks with conservative wound care of the ulcer. The right forefoot ulcer healed similarly within 5 weeks after Achilles' tendon release. Correcting the biomechanical abnormality was all that was required for healing.

Figure 2

(A–C) To remove all traces of a biofilm, a wound may be painted with methylene blue using a cotton swab prior to debridement. Note after debridement, (D) there may still be small crevices remaining that harbor bacteria. Debridement is only finished once no blue dye is left in the wound base.

Figure 3

(A, B) This patient had a collapsed Charcot midfoot with osteomyelitis and a methylmethacrylate block in the midfoot. (C) With resection of the midfoot and use of the resultant soft tissue envelopes, he underwent successful Chopart's amputation after closure, Achilles' tenectomy, and (D) immobilization with an external fixator until (E, F) he healed. (G) He has since been able walk for several years with the aid of a patellar weight-bearing brace.

Figure 4

A patient presented with a gangrenous Achilles' tendon. (A) The necrotic tendon was sharply debrided to shiny underlying tendon. (B) Hyperbaric oxygen and topical growth factor therapies were started, and (C, D) the tendon began to granulate. (E) The Achilles' tendon was then successfully skin grafted and healed completely after 4 weeks.

Figure 5

(A) This patient developed an infected Charcot ankle joint and was debrided and immobilized with an external fixator. (B) The exposed joint was covered with a muscle flap and large transposition flap. (C) The donor site was skin grafted as was (D) the anterior portion of the wound. (E) The transposition flap only needs to be long and wide enough to cover exposed joint or bone, and the rest can be skin grafted.

Figure 6

(A–D) A double rotation flap can be used to cover a plantar defect from a collapsed Charcot midfoot.

Figure 7

(A–D) A “V to Y” flap was used to close an ulcer formed by the collapse of a Charcot midfoot.

Figure 8

(A) This ulcer over a stable collapsed Charcot midfoot was (B) debrided, and a Serratus muscle free flap was used to close the wound. (C, D) The muscle was skin grafted, and the patient was able to use his foot up to 7 years of follow-up.