Functional outcome and gait analysis after triple or double arthrodesis.

Thirteen patients who had undergone unilateral triple or double arthrodesis were studied an average of 5.2 years after surgery. Patients with a neuromuscular disorder; inflammatory arthritis; or any other focus of lower extremity arthritis, deformity, or joint dysfunction were excluded from the study. Clinical and radiological assessment of the patients was performed in addition to three-dimensional kinematic and kinetic gait analysis. Objective clinical outcome based on the American Orthopaedic Ankle and Foot Society score was rated as good or excellent for 10 patients, fair for 2, and poor for 1. Two patients developed radiological evidence of arthrosis affecting other tarsal joints that was not apparent on preoperative radiographs. Two other patients had some progression of radiological arthrosis that was identified before the index surgery. The presence of radiological ankle or tarsal arthritis did not correlate with the level of the patient's pain or functional disability. Gait analysis demonstrated a 13% increase in range of flexion of the ipsilateral knee during the third rocker period of stance. At the ankle, range of motion during the same period of stance was reduced by 33%. This was mostly the result of a 6 degrees (53%) loss of plantarflexion at toe-off. Analysis of the ankle kinetic data identified a mean 13% reduction in the peak external ankle dorsiflexion moment and a 45% reduction in mean maximum power generation at the ankle in comparison to the normal side. Unilateral triple or double arthrodesis was shown to predictably result in decreased pain and increased function in otherwise normal individuals.