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Intra-articular Chondral Fragment After Acute Patellar Dislocation
The Journal of Orthopaedic and Sports Physical Therapy
|January 2, 2019
Summary
A young military cadet experienced a lateral patellar dislocation. Magnetic resonance imaging revealed a full-thickness patellar cartilage defect and a loose fragment, impacting her ability to participate in field training.
Area of Science:
- Orthopaedic Surgery
- Sports Medicine
- Radiology
Background:
- Direct-access physical therapy allows for prompt evaluation of musculoskeletal injuries.
- Patellar dislocations can occur in young, active individuals, including military cadets.
- Assessing intra-articular pathology is crucial for return to activity decisions.
Observation:
- An 18-year-old military cadet presented with a self-reduced lateral patellar dislocation.
- Initial radiographs were negative for fractures.
- Magnetic resonance imaging (MRI) was performed to evaluate for internal knee derangement.
Findings:
- MRI revealed a full-thickness articular cartilage defect on the medial facet of the patella.
- A loose body was identified within the suprapatellar pouch.
- The findings indicated significant intra-articular pathology following patellar dislocation.
Implications:
- This case highlights the importance of advanced imaging after patellar dislocation, even with negative radiographs.
- Identifying loose bodies and cartilage defects is critical for surgical planning and prognosis.
- Accurate diagnosis impacts return-to-duty decisions for military personnel and athletes.
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