Posterior Impingement Syndrome/
Os trigonum syndrome
Due to impingement of posterior aspect of talus against tibia during extreme plantarflexion – usually have an enlarged lateral posterior tubercle (Stieda’s process) or an os trigonum (non-united lateral posterior tubercle). Can also be associated with a hypertrophy or tear of the posterior inferior talofibular ligament.
Common in ballet dancers.
Pain at posterior aspect of ankle (posterior to peroneal tendons) – reproduced by extreme plantarflexion – especially in ballet dancers. Os trigonum visible on x-ray.
Activity modification; ice; electrotherapeutic modalities; corticosteroid injection; strapping to prevent extreme of plantarflexion.
Surgical removal of bone.