Improved gait function following ankle arthrodesis with corrected talus osteotomy for severe varus deformity secondary to Moyamoya-related paresis in a patient with rheumatoid arthritis: a case report.

A retrograde ankle nail combined with corrected talar osteotomy is indicated for severe ankle joint deformities owing to rheumatoid arthritis. However, the usefulness of this procedure in improving gait function remains unclear. We treated a 78-year-old woman with rheumatoid arthritis (RA) who experienced significant gait pain owing to a severe varus deformity of the ankle. She underwent corrected closed-wedge talus osteotomy and retrograde intramedullary ankle nail insertion. Preoperative analysis showed Japanese Society for Surgery of the Foot RA foot ankle scale of 44, with limited range of motion and impaired gait. Six months postoperatively, her scale improved to 69, indicating enhanced functional outcomes. Gait analysis at 6 months revealed a notable increase in stride length, gait speed, and cadence, along with a reduction in stance phase and double support duration. In addition, the swing phase increased. The painful lateral callosity of the foot disappeared postoperatively. This report emphasises the effectiveness of surgical intervention in improving gait function in patients with severe ankle deformities owing to RA. However, limitations include the absence of clubfoot correction and a relatively short follow-up period. Overall, these findings suggest that the surgical approach is beneficial for restoring mobility and alleviating pain in patients with complex ankle conditions.