Double-approach synovectomy (anterior and posterior) for diffuse pigmented villonodular synovitis of the knee: Adjuvant treatment, functional and radiographic outcomes.

Abstract

Introduction: Pigmented villonodular synovitis (PVNS) of the knee is a rare joint disease characterized by proliferation of the synovial membrane. This benign tumor can seriously affect patients' quality of life by causing disabling symptoms such as joint pain, limited movement, and painful effusions. Total synovectomy is considered the standard treatment to prevent local recurrences. However, the role of adjuvant treatments, such as radioisotopic synoviorthesis, remains controversial.

Hypothesis: The main hypothesis is that double-approach surgical synovectomy in the context of diffuse PVNS of the knee would significantly reduce recurrences and complications while improving joint function. The secondary hypothesis is that adding a radioisotopic synoviorthesis as an adjuvant treatment could enhance the effectiveness of synovectomy alone by further reducing the risk of recurrence.

Materials and methods: In this retrospective descriptive observational study, all patient records diagnosed with diffuse PVNS and who underwent a double-approach synovectomy at the CHRU of Tours between July 2007 and January 2023 were reviewed and analyzed. A total of 25 patients were included.

Results: Postoperative functional outcomes showed a marked improvement in the KSS score for functional activities (increasing from 46.54 to 83; p < 0.05) and for symptoms (decreasing from 15.09 to 4.36; p < 0.05). The overall recurrence rate observed was 16%, with a slight trend towards fewer recurrences in patients who underwent synoviorthesis (5.8% versus 37.5%; p = 0.08). The complication rate was low; only 12% of cases presented complications, including deep vein thrombosis and neuropathic pain.

Conclusion: Surgical treatment of diffuse PVNS of the knee through double-incision synovectomy appears to yield positive functional outcomes with a low recurrence rate in the treated cases. The possible addition of synoviorthesis could help reduce the risk of symptom recurrence; however, this hypothesis needs to be confirmed by further research, ideally randomized studies. The observed complications were relatively rare and manageable, which reinforces the reliability of this therapeutic approach.

Level of evidence: IV; Retrospective observational study.