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Arthroscopic Excision of Posterior Cruciate Ligament Cysts Using a Double Posteromedial Approach
Published on: October 20, 2023
Mucoid degeneration of the posterior cruciate ligament: a case report
Ken Okazaki1, Shinji Deguchi, Kenso Katai
1Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. okazaki@med.kyushu-u.ac.jp
Abstract:
We report a case of mucoid degeneration of the posterior cruciate ligament (PCL) who complained of knee joint pain on flexion. Magnetic resonance imaging (MRI) showed a diffusely thickened PCL with increased signal intensity on the T2-weighted sequence. A few intact fibers were observed with continuous margin from origin to insertion. Arthroscopy revealed yellow crumbly tissues among the PCL fibers. There was no tear of PCL fibers, thus their tension was preserved. Curettage of degenerative tissue and decompression of the PCL resulted in symptom relief without instability of the knee joint. Notably, the MRI features of mucoid degeneration of the cruciate ligament can be mistaken for those of partial tear of the ligament.
Insights
Mucoid degeneration of the posterior cruciate ligament (PCL) causes knee pain and can mimic a partial tear on MRI. Surgical decompression relieved symptoms without causing knee instability.
Area of Science:
- Orthopedic Surgery
- Musculoskeletal Radiology
Background:
- Mucoid degeneration of the posterior cruciate ligament (PCL) is a rare condition causing knee pain.
- Diagnosis can be challenging due to overlapping imaging features with ligament tears.
Observation:
- A patient presented with knee joint pain during flexion.
- Magnetic resonance imaging (MRI) revealed a thickened PCL with increased T2 signal intensity.
- Arthroscopy showed degenerative yellow, crumbly tissues within the PCL fibers.
Findings:
- The PCL fibers remained intact with preserved tension, ruling out a tear.
- Curettage of the degenerative tissue and PCL decompression led to symptom relief.
- No knee joint instability was observed post-procedure.
Implications:
- This case highlights the importance of differentiating PCL mucoid degeneration from partial tears on MRI.
- Conservative surgical management (curettage and decompression) can effectively treat PCL mucoid degeneration.
- Accurate diagnosis through combined imaging and arthroscopic findings is crucial for successful patient outcomes.
