The metabolic cost of walking after undergoing a Syme’s ankle disarticulation is minimally more than that for someone without an amputation, the ability to end weight bearing makes prosthetic fitting relatively simple, and few patients require extensive rehabilitation or placement in a skilled nursing or rehabilitation facility. In spite of these potential benefits, data about the long-term outcomes following Syme’s amputation was lacking. Consequently, researchers at Loyola University Health System, Maywood, Illinois, sought to add to the literature. Their study was published April 11 in Foot & Ankle International.
They identified 51 patients who had undergone single-stage Syme’s ankle disarticulations with excision of the lateral and medial malleoli by a single surgeon during a 23-year period. None of the 51 patients had sufficient tissue to allow amputation at the transmetatarsal or tarsometatarsal levels. Thirty-three patients underwent amputation due to a diabetes-related forefoot infection; 11 amputations were secondary to a crush injury; three were due to an infection unrelated to diabetes; three were due to a noncorrectable acquired deformity; and one was due to neoplasm. The average age at surgery for the patients with diabetes was 62.1 years (range = 36-81 years), with an average follow-up of 6.8 years (range = 4-11.6 years). The patients without diabetes had an average age of 37.8 years (range = 21-65 years), with an average follow-up of 9.3 years (range = 2.2-25 years). Patients who were alive and could be contacted were invited to complete the Short Musculoskeletal Function Assessment (SMFA) questionnaire that was scored for functional, mobility, and bothersome indices.
Of the 33 patients with diabetes, 17 had died and four (12.1 percent) were converted to transtibial amputations. One of the patients without diabetes died, and one (5.5 percent) was converted to transtibial amputation. Eleven of the 33 patients who were contacted completed the SMFA. All of these patients demonstrated favorable outcome scores in the mobility, functional, and bothersome indices (average mobility index of 17.2, functional index of 14.7, and bothersome index of 16.7 for patients with diabetes compared to 34.7, 29.9, and 30.6 for patients with diabetes, respectively).
The information derived from the investigation supports the opinion that patients who underwent Syme’s ankle disarticulations appear to fare better than similar patients with transtibial amputations and refutes the notion of high complication rates and difficulties with prosthetic fitting, according to the study’s authors. These patients required less rehabilitation and achieved improved levels of functional independence as demonstrated by favorable functional, mobility, and bothersome indices.
