Realignment surgery for severe talar tilt secondary to paralytic cavovarus.

BACKGROUND: Realignment surgeries for mild to moderate ankle osteoarthritis with minimal talar tilt have been reported to be effective. However, there has been no report on joint-sparing surgery of ankle osteoarthritis in patients with paralytic disorders who have severe talar tilt. We therefore investigated whether ankle osteoarthritis with severe talar tilt caused by paralytic disorders can be improved after operative treatment.

METHODS: This study included 12 ankles (11 patients) with varus ankle osteoarthritis from paralytic disorders with cavovarus deformity of the foot. Mean follow-up period was 3.0 years (range, 2-4.5 years). Causes of paralysis were residual polio in 7 ankles (6 patients), cerebral palsy in 2 ankles, and idiopathic in 3 ankles. Preoperative and postoperative clinical assessments were performed using the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score and a visual analogue scale (VAS). The Ankle Osteoarthritis Scale (AOS) was used for postoperative assessment. Pre- and postoperative radiographic parameters were compared.

RESULTS: Mean AOFAS score improved from 39.1 (range, 32-57) preoperatively to 77.9 (range, 72-85) postoperatively. Mean talar tilt improved from 17.4 degrees (range, 9.5-33.5 degrees) to 1.4 degrees (range, 0-4 degrees). Degree of osteoarthritis according to Takakura classification improved in all ankles except two. Mean heel alignment angle was reduced from 40.4 degrees (range, 2-65 degrees) of varus preoperatively to 11.2 degrees (range, -3 to 25.5 degrees) of varus postoperatively.

CONCLUSION: Medial varus ankle osteoarthritis from paralytic cavovarus may be improved even in cases of severe talar tilt.

LEVEL OF EVIDENCE: Level IV, retrospective case series.