Single medial approach to modified double arthrodesis in rigid flatfoot with lateral deficient skin.

BACKGROUND Triple arthrodesis through a two-incision approach is the traditional surgical treatment of fixed flatfoot in adults. However, since it limits motion and forces the remaining joints to absorb more load, long-term studies report diminishing results over time from symptomatic breakdown of adjacent joints. In addition, wound-healing problems have been reported in up one-third of patients undergoing a major flatfoot reconstruction which are more commonly associated with the anterolateral approaches. Therefore, since 2003, we have been interested in selective arthrodesis of the subtalar and talonavicular joints sparing the uninvolved calcaneocuboid joint and the lateral skin. MATERIALS AND METHOD We have performed this procedure in 11 patients (14 feet) who had deficient lateral skin and a fixed hindfoot valgus deformity where adequate correction may have led to lateral wound complication. They were followed in a prospective fashion and assessed at a minimum of 6 months followup. RESULTS Wound healing occurred without any complications in all cases. Evaluation was performed at an average of 21.5 (range, 6 to 50) months. Significant radiographic improvements were observed on each measurement: anteroposterior talonavicular coverage angle improved from 38.5 degrees to 7 degrees, lateral talo-first metatarsal angle improved from 21 degrees to 0 degrees, hindfoot frontal alignment angle improved from 18 degrees to 7.5 degrees. All patients had an asymptomatic calcaneocuboid joint. CONCLUSION Arthrodesis of the subtalar and talonavicular joints through a medial approach combined with peroneal lengthening is a reliable procedure for the treatment of rigid flatfoot with deficient lateral skin without calcaneocuboid joint degeneration.