The drop toe sign: an indicator of neurologic impairment in congenital clubfoot.

UNLABELLED: Nine patients presenting during infancy were identified with clubfeet and absent anterior and lateral compartment functions. We considered these to be neurogenic clubfeet. All patients had the drop toe sign: resting posture of the toes in plantarflexion and absent active dorsiflexion movement after plantar stimulation of the foot. Two patients (three feet) underwent exploration of the peroneal nerve, which revealed anatomic abnormalities. Six patients required more casts than typical for initial correction of deformity; all but two had Achilles tenotomy. Four relapsed despite full-time bracing and eventually needed intraarticular surgery to achieve a plantigrade foot. Idiopathic absent peroneal nerve function is not a well-described entity in the clubfoot literature. All babies with clubfoot should be examined for the drop toe sign. When noted, the feet will likely be more difficult to correct initially, may need early Achilles tendon lengthening, will likely need permanent bracing, are likely to relapse and need intraarticular surgery, and may need multiple surgeries to remain plantigrade throughout growth. LEVEL OF EVIDENCE: Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.