Tenosynovial giant cell tumor arising from the posterior cruciate ligament: a case report and literature review.

The localized form of tenosynovial giant cell tumor or pigmented villonodular synovitis is rarely intraarticular in the knee. We reported a 40-year-old woman with a tenosynovial giant cell tumor arising from posterior cruciate ligament (PCL). She suffered sudden knee pain and locking without any reason for two days. A mass with a size of 1.7 × 0.8 × 0.7 cm in the fossa intercondyloidea was detected on the MRI. After one time hyperextension physical examination the patients felt sudden pain relief. During the arthroscopy examination, a loose soft tissue mass was found under the lateral meniscus. Only the synovium tissue lesion on the proximal PCL was detected. The mass had a conceivable thin pedicel and the shape matched well with the tumor bed on the PCL. The histopathology of the mass demonstrated a tenosynovial giant cell tumor. At six weeks follow-up, no clinical evidence of recurrence was noted. A Literature Review of tenosynovial giant cell tumor or pigmented villonodular synovitis arising from the PCL is present.