Subtalar osteoarthritis
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Diagnosis certain
Presentation
Two years of mechanical ankle pain. No history of trauma.
Patient Data
Age: 50 years
Gender: Female
From the case:
Subtalar osteoarthritis
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There are advanced changes of osteoarthritis in the posterior subtalar joint with subchondral sclerosis, loss of cartilage and osteophyte formation. Os trigonum is prominent, likely secondary to the osteoarthritis.
Case Discussion
There was no evidence of previous trauma (including calcaneal fractures) in this patient. Other possible causes included instability, inflammatory arthritides or tarsal coalition. Primary osteoarthritis of the subtalar joint is rare but may be the cause in this patient in the absence of other conditions.