Presentation
Severe knee pain during football game after doing vigorous exercise.
Patient Data
Age: 25 years
Gender: Male
From the case:
Posterior cruciate ligament avulsion fracture
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The patient encountered a hyperextension injury of the knee with the resultant constellation of findings:
- avulsion fracture of the PCL with bony fragment from its tibial attachment
- horizontal tear of the lateral meniscus with large parameniscal cyst
- abnormal signal within the belly of popliteus muscle likely hematoma with intact popliteal tendon
- bone bruise at the posterolateral corner of the tibial plateau
Lateral collateral ligament, biceps femoris tendon, popliteo-fibular ligament, arcuate ligament and iliotibial tracts are intact.
From the case:
Posterior cruciate ligament avulsion fracture
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The white arrows point to the parameniscal cyst.
The red arrow refers to the torn posterior root ligament of lateral meniscus.
Dashed blue arrows refer to the popliteus muscle which is enlarged and shows abnormal signal
Case Discussion
Hyperextension of the knee can induce overstretch of the PCL with avulsion of its bony attachment at the tibia as in this case.