Presentation
Direct fall onto the flexed left knee. Swollen knee upon physical examination with positive patellar tap test.
Patient Data
Age: 25 years
Gender: Male
From the case:
Patellar fracture
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Radiographs revealed a comminuted patellar fracture. There is moderate knee joint effusion.
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Knee joint effusion annotated.
Case Discussion
Patellar fractures are usually caused by direct trauma, such as a fall from standing height onto the flexed knee or a dashboard impact from a motor vehicle collision.
In this case, there is also a noticeable knee joint effusion. It is always important to be aware of joint effusion in a trauma scenario as it might be a sign of a hidden injury.