Presentation
Post-traumatic knee pain.
Patient Data
Age: 51 years
Gender: Male
From the case:
Fractured fabella
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Lateral radiograph of the right knee shows a transverse radiolucent fracture line with irregular borders across an ossified fabella (arrow) consistent with fracture of the fabella. No definite fracture is evident in the frontal view. Mild osteoarthritis changes of the knee joint. Slight distension of the suprapatellar bursa by likely small joint effusion.
From the case:
Fractured fabella
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Arrow indicates fractured fabella.
Case Discussion
Fracture fabella is a rare entity usually post-traumatic or a stress fracture in patients with total knee replacement. The rare differential diagnosis is bipartite fabella with well-corticated regular margins.