Background: Pigmented villonodular synovitis of the hip is a rare
disease. Synovectomy is generally accepted as the only surgical treatment for
the disorder, but there have been few studies with a sufficient sample size
and duration of follow-up to allow the evaluation of long-term outcomes. The
aim of this study was to determine the long-term outcome of the treatment in
Methods: Sixteen patients (nine men and seven women), with a mean
age of 35.5 years at the time of surgery, were treated between 1970 and 1996.
Complete synovectomy was performed in all patients; in addition, three had a
cup arthroplasty, four had a total hip arthroplasty, and one had a monopolar
arthroplasty. Clinical and radiographic outcomes were evaluated
retrospectively at a mean of 16.7 years postoperatively. Only one patient was
followed for less than eight years.
Results: Nine patients needed repeat surgery, but only one had
recurrent synovitis, as detected with pathological examination fourteen years
after treatment with synovectomy and cup arthroplasty. Secondary
osteoarthritis developed in all eight patients who had been treated with
synovectomy alone, and four of them required a total hip arthroplasty within
the follow-up period.
Conclusions: These results support earlier data indicating that
osteoarthritis consistently develops in patients with pigmented villonodular
synovitis of the hip. Complete synovectomy seems to be effective in preventing
recurrence of the synovitis, but it does not appear to prevent the development
of secondary osteoarthritis.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.