Foot & ankle international
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Comparative Study
Effects of a UCBL orthosis and a calcaneal osteotomy on tibiotalar contact characteristics in a cadaver flatfoot model.
A flatfoot deformity alters the contact characteristics of the ankle joint, shifting the location of articulation posterolaterally, increasing pressure, and decreasing the contact area within the ankle. These changes may explain the pattern of articular degeneration and subsequent angulation observed in a long-standing adult acquired flatfoot. Corrective orthoses and surgical reconstruction have been used to realign pes planovalgus feet, but the effects of these treatments on tibiotalar contact characteristics are unknown. We hypothesized that realignment of a flatfoot with either corrective orthosis or surgical reconstruction would restore the contact characteristics of the ankle to the intact state. ⋯ The changes observed in the magnitude and location of the mean and peak pressures indicate that the UCBL orthosis and calcaneal osteotomy altered hindfoot alignment to significantly influence tibiotalar contact characteristics. The results further suggest that the UCBL orthosis corrected ankle malalignment better than the calcaneal osteotomy in an adult acquired flatfoot. This study provides biomechanical data to support the clinical impression that realignment of the hindfoot corrects the pathologic tibiotalar contact characteristics associated with an adult acquired flatfoot. The results support the conclusion that the clinical management of a pes planovalgus foot with a UCBL orthosis or a medial translational osteotomy of the calcaneus may avert the onset of pantalar disease seen with late-stage posterior tibial tendon dysfunction.