Treatment of Stage II Adult Acquired Flatfoot Deformity With Subtalar Arthroereises.

UNLABELLED: The role of arthroereises in the treatment of adult acquired flatfoot deformity (AAFD) has been controversial. This study aims to evaluate the outcome of subtalar arthroereisis in treating stage II AAFD. A total of 24 feet with stage II AAFD were treated surgically between 2009 and 2011 using subtalar arthroereisis. The average follow-up was 29.7 months (range = 24 to 35 months). The average postoperative AOFAS (American Orthopaedic Foot and Ankle Society) Ankle-Hindfoot Scale score was 85.6 (compared with 51.7 preoperatively). Average preoperative talar-first metatarsal angle and talonavicular coverage angle were -13.9° and 38.3°, respectively. The average postoperative angles were 1.6° and 11.2°, respectively (P < .01). No deformity recurrences were found at the time of last follow-up, with the exception of 1 case. Subtalar arthroereisis appears to be a reasonable treatment option for stage IIA and IIC AAFD. It can be used alone to correct mild hindfoot valgus, and it can also be performed with a calcaneal osteotomy to gain more correction in severe stage II AAFD. LEVELS OF EVIDENCE: Therapeutic, Level IV: Retrospective Case Series.