Supramalleolar Lateral Closing Wedge Osteotomy for the Treatment of Varus Ankle Arthrosis

Abstract

Background: Medial ankle joint pain with localized cartilage degeneration due to medial joint overload in varus malalignment of the hindfoot lends itself to treatment by lateral closing wedge supramalleolar osteotomy. Methods: From 1998 to 2003, nine patients between the ages of 21 to 59 years were operated. The etiology of the malalignment and degeneration was posttraumatic in eight and childhood osteomyelitis in one. Preoperative and postoperative standing radiographs were analyzed to determine the correction of the deformity and the grade of degeneration. Function and pain were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale. The average followup was 56 (range 15 to 88) months. Results: The average time to osseous union was 10 ± 3.31 weeks. There were no operative or postoperative complications. The average AOFAS score improved from 48 ± 16.0 preoperatively to 74 ± 11.7 postoperatively ( p < 0.004). The average pain subscore improved from 16 ± 8.8 to 30 ± 7.1 ( p < 0.008). The average tibial-ankle surface angle improved from 6.9 ± 3.8 degrees of varus preoperatively to 0.6 ± 1.9 degrees of valgus postoperatively ( p < 0.004). In the sagittal plane, the tibial-lateral-surface angle remained unchanged. At the final followup, two patients showed progression of radiographic ankle arthrosis grades. In one patient, it rose from grade 0 to I. In the other patient it advanced from grade II to III, with subsequent ankle arthrodesis required 16 months after the index procedure. Seven patients returned to their previous work. Conclusions: Lateral supramalleolar closing wedge osteotomy was an easy and safe procedure, effectively correcting hindfoot malalignment, relieving pain, restoring function, and halting progression of the degeneration in the short-term to mid-term in seven of nine patients.