The appearance of the tarsal navicular after posteromedial release for clubfoot.

Sixty-one idiopathic clubfeet in 46 patients of an older population were treated by one-stage posteromedial release. Follow-up roentgenograms revealed dorsal subluxation of the tarsal navicular in 43% of the clubfeet. This abnormality is probably due to both closed manipulation and casting, and improper positioning of the navicular during posteromedial release. However, dorsal navicular subluxation did not adversely affect the results of treatment observed over the follow-up period that averaged nearly 6 1/2 years. Medial subluxation of the navicular was associated with unsatisfactory results, whereas a centrally located or laterally subluxed navicular generally produced good or excellent results. Other abnormalities of the navicular noted included wedging and avascular necrosis. The long-term consequences of these various abnormalities of the roentgenographic appearance and position of the navicular are not known.