Avascular Necrosis Of The Knee After Arthroscopy: Treatment With Minimally Invasive Knee Arthroplasty

Peter Bonnutti, Michael Mont, and Margot McMahon

Introduction: Avascular necrosis of the knee has recently been described to occur after various arthroscopic procedures around the knee. In this report, we described 19 cases that were treated with either a uni- or tricompartmental knee arthroplasty.

Materials and Methods: In this study, we characterized nineteen patients (19 knees) that were treated with a diagnosis of avascular necrosis that occurred after a knee arthroscopy. All of the knees had magnetic resonance imaging prior to the arthroscopy that were negative for avascular necrosis. Knees in the study had positive MRI findings and severe symptomatology requiring further treatment. Operative procedures performed included unicondylar (n=3) and total knee arthroplasties (n=16).

Results: Six patients had an arthroscopy with laser treatment, 7 had Arthrocare (radiofrequency) assistance, with 6 others having no special adjuncts. There were 5 men and 14 women with a mean age of 69 years (range, 42-86). All knees were doing well clinically (mean KSS score of 95 points, range 91-100), at a mean follow-up of 4 years (range, 2 to 7 years). Minimally invasive approaches were utilized for all knees.

Discussion: Avascular necrosis of the knee after arthroscopy is an uncommon and not well-characterized disorder. It can be successfully treated with minimally invasive uni or tricompartmenta;l knee arthroplasty,