A newborn has a convex, boat-shaped sole with the hindfoot in equinus and a rigid forefoot abducted dorsally. Forced plantarflexion stress radiographs fail to align the navicular with the talar head. Which statement about this condition is correct?

• A It is reducible and managed with Ponseti casting alone
• B The talus is normally aligned with the first metatarsal on weight-bearing views
• C It represents a lateral dislocation of the talonavicular joint and usually requires surgical correction ✓
• D It is a flexible deformity identical to physiological flatfoot

Explanation

Congenital vertical talus is a rigid rocker-bottom foot caused by lateral dislocation of the talonavicular joint with the talus fixed in equinus and vertical orientation. Unlike oblique talus, where the navicular realigns on forced plantarflexion stress films, the dislocation here persists, so serial casting cannot achieve reduction and surgical reduction, traditionally open, now often by the Dobbs technique, is required. Physiological flatfoot is flexible with an intact talonavicular articulation.

Reference: Tachdjian's Pediatric Orthopaedics, 5th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.