Traction apophysitis of the medial malleolus.

We report the cases of three children with chronic injuries of the medial tibial malleolus caused by traction injuries during sport. All three had the triad of swelling of the medial malleolus, tenderness over its anterior part, and pain on forced valgus movement of the foot. Radiographs showed bilateral accessory ossification centres and MRI demonstrated partial avulsion or avulsion fracture of the apophyseal cartilage and fragmentation of the accessory centres. A review of 134 young basketball players showed that 25% had tenderness of the anterior medial malleolus. This high rate indicates that traction apophysitis of the medial malleolus is not uncommon in children as a sports-related disorder.