Higher incidence of diffuse Pigmented Villonodular Synovitis in patients with ruptured cruciate ligament: A case report

INTRODUCTION: Pigmented Villonodular Synovitis (PVNS) is a kind of extremely rare and not easily diagnosed disease, while the occurrence following the anterior cruciate ligament (ACL) rupture is comparably high. CASE PRESENTATION: Here we reported 2 patients presenting knee swelling, pain, and giving away symptoms following a rupture of ACL history. Clinical and radiological findings were supportive of ACL rupture and PVNS, prompting the patient to undergo surgery. The synovium was completely removed with the help of an arthroscope. Reconstruction of the ruptured ACL was carried out a few months later. At the last follow-up visit, both the patients were doing well with no recurrence of pain, swelling, or give way sensation. DISCUSSION: The diagnosis of PVNS is often difficult because in the early stages, symptoms are often non-specific and pathological examination remains the gold standard for the diagnosis of PVNS. We have reviewed some of the previously reported literature on PVNS, suggesting that joint instability may be an important risk factor for PVNS and summarizing the treatment options for PVNS. CONCLUSION: More attention should be paid to the incidence of PVNS in patients with joint instability, particularly in patients with cruciate ligament injuries. Early and reliable stabilization of the joint may significantly prevent PVNS and ensure a better clinical outcome.