A mid-term follow-up of Koutsogiannis’ osteotomy in adult-acquired flatfoot stage II and “early stage III”

INTRODUCTION Koutsogiannis' osteotomy has been widely described to treat adult-acquired flatfoot. However, few articles describe its midterm follow-up. Our aim was to study clinical and radiological outcomes at least one year after surgery and to analyze whether a combined procedure on the medial soft tissue affected these outcomes. METHODS We performed a retrospective study of 30 feet of patients who underwent a Koutsogiannis' osteotomy due to adult-acquired flatfoot stage II and "early stage III": a stage III acquired flatfoot without any important structural deformities. The parameters studied were additional medial soft tissue procedures, clinical outcome through the American Orthopaedic Foot and Ankle Society (AOFAS) ankle and midfoot score as well as complications and radiological measurements. RESULTS Sixteen cases were "early stage III" and 14 stage II. Thirteen patients underwent an associated posterior tibial tendon (PTT) revision: in three cases an end-to-end suture was possible, seven cases needed a FDL transposition, and three underwent synovectomy. Statistically significant improvement was found in the AOFAS score although no significant changes were seen radiologically. No additional benefit was found with the revision of the posterior tibial tendon. As to clinical and radiological results, no differences were found between stage II and "early stage III". Five cases presented a mild dysesthesia but only one patient needed neurolysis. CONCLUSIONS We consider the Koutsogiannis' osteotomy to be a safe and effective procedure to reduce pain in patients with stage II and "early stage III" adult-acquired flatfoot.