Treatment of severe, painful pes planovalgus deformity with hindfoot arthrodesis and wedge-shaped tricortical allograft

Background: This study tested the hypothesis that modification of the standard technique of hindfoot arthrodesis with the use of a wedge-shaped tricortical allograft would improve the amount of correction of pes planovalgus deformity. The results were compared to previous reports. Methods: Between 1998 and 2005, the senior author (LBC) performed 13 hindfoot arthrodeses on 12 patients using an allograft to improve correction of the deformity for severe, painful pes planovalgus deformity. The average patient age was 55 (range 27 to 77) years. There were seven women and five men. The indications were posterior tibial tendon dysfunction (seven feet), rheumatoid arthritis (three feet), post-traumatic arthritis and deformity (one foot), congenital pes planovalgus (one foot), and tarsal coalition (one foot). Results: Twelve of 13 feet achieved union by 12 weeks postoperatively. There was one nonunion. The average time to fusion was 12 weeks. All 12 patients were satisfied with the results of the operation. The average postoperative American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot score was 87 points, and the AOFAS Midfoot score was 85 points. Preoperative and postoperative radiographs were compared to evaluate correction of deformity. On lateral weightbearing views, the talo-first metatarsal angle improved from 15 to 6 degrees, and the lateral talocalcaneal angle improved from 48 to 35 degrees. On anteroposterior views, the talo-first metatarsal angle improved from 17 to 7 degrees, the talonavicular coverage decreased from 28 to 13 degrees, and the talocalcaneal angle improved from 23 to 13 degrees. Conclusions: A simple modification of the addition of allograft to a common procedure of hindfoot arthrodesis to treat severe, painful pes planovalgus results is reliable and offers satisfactory correction.