Cotton Osteotomy in Flatfoot Reconstruction: A Case Report Highlighting Surgical Technique and Modified Incision to Protect the Medial Dorsal Cutaneous Nerve

The Cotton osteotomy or opening wedge medial cuneiform osteotomy is a useful adjunctive flatfoot reconstructive procedure that is rarely performed in isolation. The Cotton procedure is relatively quick to perform and effectively corrects forefoot varus deformity after rearfoot fusion or osteotomy to achieve a rectus forefoot to rearfoot relationship. Proper patient selection is critical, because preoperative findings of medial column joint instability, concomitant hallux valgus deformity, or degenerative joint disease of the medial column might be better treated with arthrodesis of the naviculocuneiform or first tarsometatarsal joints. Procedure indications also include elevatus of the first ray, which can be a primary deformity in hallux limitus, or iatrogenic deformity after base wedge osteotomy in hallux valgus. We present the case of an adolescent patient who underwent flatfoot reconstruction, including Cotton osteotomy for correction of forefoot varus that was accentuated after double heel osteotomy. This case highlights our preferred procedure technique, including the use of a nerve-centric incision design. The use of an oblique dorsal medial incision is primarily intended to minimize the risk of trauma to the medial dorsal cutaneous nerve. At 20 months postoperatively for the right extremity and 12 months postoperatively for the left extremity, sensation remained intact, and the patient had not experienced any postoperative nerve symptoms. The patient had returned to playing sports without pain or restrictions.