Pigmented villonodular synovitis, or PVNS, is a disease caused by the abnormal growth of the hip joint’s lining tissue, known as the synovium. Excessive growth of this tissue leads to inflammation in the joint causing pain, tenderness, and stiffness. The condition occurs most commonly in patients in their 30s and 40s, but the actual cause of PVNS is still unknown.
PVNS is identified in two different forms:
- Localized – Pain and swelling occurs in just one area of the joint, and responds well to treatment.
- Diffuse – More common than localized PVNS, diffuse PVNS involves the entire joint, and can be more destructive and difficult to treat.
Symptoms of PVNS include hip pain, weakness, and stiffness of the joint. Patients with localized PVNS may experience joint locking, a catching sensation or a feeling of instability. Patients with diffuse PVNS may experience a gradual onset in symptoms.
PVNS may not necessarily be evident on a standard X-ray, though an X-ray could show other potential problems that could be causing the hip pain. Dr. Anz may choose to order an MRI scan that will more accurately show evidence of a nodular mass with bone changes if the condition is localized PVNS. If the condition is diffuse PVNS, an MRI will show a thickening of the joint lining or an extensive mass, potentially with destructive bone changes.
In some cases Dr. Anz may perform a procedure called a joint aspiration, whereby he releases fluid from the hip joint. Typically with PNVS cases, the joint fluid appears bloody. A biopsy is the confirmatory test for PVNS of the hip.
Surgery is the best option to treat a diagnosis of PVNS. Dr. Anz will remove the painful, inflamed synovial lining through a procedure called a synovectomy, which, can be done via arthroscopic or open surgery.
In an arthroscopic synovectomy, Dr. Anz surgically removes the affected lining with the mass only using small incisions. This is the most common way to treat localized PVNS. However in the instance of diffuse PVNS, a total synovectomy may be required, which is an open surgery procedure that removes the mass and the entire joint lining.
Following a synovectomy, patients should avoid full weight bearing as discussed with Dr. Anz at the first post-operative visit. For patients recovering from arthroscopic procedures, the recovery time is shorter, and will involve a short course of physical therapy before resuming normal daily activities. However for those who undergo the open procedure, a more extensive physical therapy program will be prescribed to prevent post-op stiffness and a return to normal mobility, often taking months.
For more information on PVNS (pigmented villonodular synovitis) or other disorders of the hip, please contact the Gulf Breeze, Florida orthopedic surgeon, Dr. Adam Anz located at the Andrews Institute.