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Foot & Ankle
intermediate
X-Type

Os Trigonum - Posterior Ankle Impingement

Posterior Ankle Pain

A 19-year-old professional ballet dancer presents with chronic posterolateral ankle pain aggravated by going "en pointe." Examination reveals tenderness posterior to the lateral malleolus, pain with forced plantarflexion, and clicking with ankle motion. Lateral radiograph shows a separate ossicle posterior to the talus. Regarding os trigonum and posterior ankle impingement:

Mark each as TRUE or FALSE

A

The os trigonum is an accessory ossicle representing a separate ossification center of the lateral t...

B

Posterior ankle impingement syndrome (os trigonum syndrome) occurs when the os trigonum is compresse...

C

Os trigonum is always symptomatic when present; it only occurs in ballet dancers; the Stieda process...

D

The flexor hallucis longus (FHL) tendon runs between the medial and lateral tubercles of the posteri...

E

Clinical examination findings include posterolateral ankle tenderness (posterior to peroneal tendons...

Answer the questions to see explanations

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