Checkrein deformity after ankle fracture

Flexor hallucis longus muscle can adhere to the distal tibia after tibial fracture. The patient may complain of deep posteromedial ankle pain, checkrein deformity of the hallux, hallux flexus or development of hallux rigidus. FHL tightness or checkrein deformity needs to be treated surgically either by lengthening or release of FHL muscle.1 Tethering of the flexor hallucis longus (FHL) tendon seen as a dynamic flexion deformity of the hallux. When the ankle is passively dorsiflexed, the flexion deformity becomes more prominent, but on passive plantar flexion the deformity is corrected completely. Checkrein deformity has been explained by either entrapment of the FHL in scar tissue or callus at the fracture site,2 but or as a results from contracture of the muscles after a subclinical compartment syndrome.3