The transmetatarsal amputation has been performed for over 40 years as a limb salvage procedure, in diabetic patients with nonhealing ulcerations or nonreconstructible ischemia. It is generally believed that the transmetatarsal amputation provides a better walking extremity than a more proximal amputation and is more energy efficient. A review of the literature reveals little regarding the biomechanics of the "short foot." The authors will review the functions of the myofascial structures in both the normal foot and the transmetatarsal amputation and discuss the influence of mechanics on transmetatarsal amputation lesions.
Neuropathic ulcerations in diabetic patients are frequent causes of hospitalizations and morbidity. The plantar aspect of the first metatarsophalangeal joint is a common location for these ulcerations, because of the significant weightbearing forces generated through this joint and the presence of sensory and motor neuropathy. The authors describe 24 cases in which excision of the tibial sesamoid, fibular sesamoid, or both, was performed to resolve these lesions.
While the transmetatarsal amputation has resulted in the salvage of numerous diabetic limbs, it remains an ablative procedure with both short- and long-term complications. The authors reviewed their experience with the panmetatarsal head resection as an alternative to the transmetatarsal amputation. A retrospective review was performed of all patients having undergone this procedure between May 1986 and November 1991. Thirty-seven procedures were performed; of these, 34 were evaluated. The average follow-up period was 20.9 months. Thirty-two feet showed primary healing while one showed delayed healing. One patient had local recurrence of the original ulceration. Primary healing was 94% while overall success was 97%. No patient required amputation of any kind. The authors conclude that the panmetatarsal head resection is a viable alternative to the transmetatarsal amputation in properly selected patients because it avoids many of the structural and biomechanical pitfalls of the transmetatarsal amputation.
Recurrent ulceration following transmetatarsal amputation commonly results from hypertrophic bone formation or equinus deformity. In the current study, 31 diabetic patients underwent 33 Achilles tendon procedures for recurrent ulcerations at the distal stump of their transmetatarsal amputation. Primary healing was achieved in 21 procedures (64%) and secondary healing in 9 procedures (27%) for an overall healing rate of 91%. Two procedures failed to resolve the original ulceration (6%). The average follow-up examination was 27 months. The authors conclude that Achilles tendon procedures are an effective means of managing ulcerations in transmetatarsal amputation feet exhibiting an equinus deformity.
The records of 52 patients who underwent metatarsal osteotomies for the treatment of chronic neuropathic ulcerations between the years 1983 and 1985 were analyzed in a retrospective study. Long-term follow-up information was available for all but three patients. All patients were conservatively managed preoperatively and postoperatively with shoes, accommodative orthoses, and local care. A limb salvage rate of 94%, 46 of 49 patients, was achieved in this study. Although 13 patients developed transfer ulcerations, all but one were managed either with conservative care or a lesser podiatric procedure, and all remain healed to date.