15-yr-old with right ankle pain and difficulty in walking up
A 15-year-old male patient presented with difficulty walking uphill during the past 2.5 years due to involuntary flexion of the first, second and third toes of his right foot and limited ankle dorsiflexion. He reported difficulty with other movements that require maximal ankle dorsiflexion, including deep squats.

He had mild discomfort with these movements and noted bothersome callus formation occurred over the dorsal interphalangeal joint of the hallux and the distal plantar aspect of the first three toes. He had not received any treatment. The patient has a history of a right triplane ankle fracture with an associated fibula fracture that occurred approximately 3 years prior. At the time of injury, he underwent internal fixation through a medial approach to the tibia and lateral approach to the fibula.

On physical exam, active range of motion was mildly limited in dorsiflexion. Flexion contracture of the interphalangeal joints of the first, second and third digits was seen with the right ankle in a plantigrade position that worsened with further ankle dorsiflexion to 5° and returned to neutral with plantar flexion.

He was diagnosed with checkrein deformity of the right foot involving the first three toes. A checkrein deformity is a dynamic flexion contracture of the interphalangeal joints of the hallux and lesser toes due to tethering of the flexor hallucis longus (FHL), which is exaggerated with ankle dorsiflexion and reduces with plantar flexion.

The delayed development of this pathology after the patient’s history of triplane and fibular fracture after internal fixation points to an etiology of FHL tethering due to adhesions at the posterior distal tibia where the prior injury occurred.

This tethering of the FHL creates an exaggerated tenodesis effect at the ankle, which gives rise to the characteristic increase in deformity with ankle dorsiflexion and resolution with plantar flexion. The corresponding manifestations in the second and third digit arise due to tendinous tethers between the FHL and flexor digitorum longus (FDL) tendons distally.

Continue reading here: https://pxmd.co/V03ds