Isolated navicular-medial cuneiform tarsal coalition revisited: a case report.

Tarsal coalitions between the navicular and the cuneiforms occur infrequently when compared with the more common talocalcaneal and calcaneonavicular coalitions. Isolated cases of navicular-medial cuneiform coalitions have only rarely been reported; however, the diagnosis is likely underrecognized. Conservative management should be pursued initially for symptomatic patients, followed by surgical options for unresponsive cases. The few reports available recommend treatment with navicular-medial cuneiform fusions, but long-term follow-up is not available to assess outcome and it remains unclear whether an isolated arthrodesis of the navicular-medial cuneiform joint will in turn lead to differing biomechanics of adjacent joints. We report a case of a patient with an isolated navicular-medial cuneiform coalition, treated with resection and free-fat interposition rather than arthrodesis. To our knowledge, this is the first case of a navicular-medial cuneiform coalition reported in a patient of North American ancestry. At 2 years postoperatively, she is pain-free with all activities and has full range of motion of her ankle and subtalar joints, and full mobility at the navicular-medial cuneiform joint. This unique method provided a successful solution to this difficult situation.