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OrthoVellum

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Foot & Ankle
intermediate
X-Type

Os Trigonum Syndrome

Posterior Ankle Impingement

A 22-year-old professional ballet dancer presents with posterior ankle pain that worsens with plantarflexion activities, particularly during en pointe positions. She has tenderness posterior to the ankle between the Achilles tendon and the peroneal tendons. Forced plantarflexion reproduces her pain. Lateral radiograph shows an accessory ossicle posterior to the talus. Regarding os trigonum syndrome:

Mark each as TRUE or FALSE

A

The os trigonum is an accessory ossicle representing failure of fusion of the lateral tubercle of th...

B

Os trigonum syndrome is a form of posterior ankle impingement, most common in dancers (ballet, espec...

C

Os trigonum is extremely rare (less than 1%); it represents a fracture of the talus; it is always un...

D

Differential diagnosis includes flexor hallucis longus (FHL) tendinitis (often coexists, tenderness ...

E

Treatment: initial conservative management includes activity modification, NSAIDs, physiotherapy, an...

Answer the questions to see explanations

Click T (True) or F (False) for each option