First metatarsophalangeal arthrodesis: a clinical, pedobarographic and gait analysis study

Abstract

This study investigated the results of first metatarsophalangeal (MTP) arthrodesis in terms of clinical outcome measures, plantar pressure distribution, and gait patterns. Ten feet in nine patients with severe hallux rigidus (HR) who underwent first MTP arthrodesis were studied. The preoperative evaluation included a subjective questionnaire, physical exam, AOFAS hallux score, radiographs and dynamic pedobarography (EMED). At follow-up (average 34 months) these were repeated, and gait analysis studies were obtained. Patients showed significant clinical improvement based on the subjective criteria. The mean AOFAS score improved from 38 preoperatively to 90 postoperatively. Postoperative EMED analysis showed restoration of the weightbearing function of the first ray, with greater maximum force carried by the distal hallux at toe-off. Kinematic and kinetic gait analysis from each patient's operative limb were compared to the unaffected contralateral limb and to age- and sex-matched healthy subjects. The kinematic data indicated a significantly shorter step length with some loss in ankle plantar flexion at toe-off on the fused side. The kinetic data indicated a reduction in both ankle torque and ankle power at push-off. Clinical results indicated effective pain relief and a high level of patient satisfaction, consistent with previous reports in patients with symptomatic Hallux Rigidus.