Article

The Lateral Compartment in Knees With Isolated Medial and Patellofemoral Osteoarthritis A Histologic Analysis of Articular Cartilage

Department of Orthopaedic Surgery, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, USA.
The Journal of arthroplasty (Impact Factor: 2.37). 08/2011; 26(5):783-7. DOI: 10.1016/j.arth.2010.07.004
Source: PubMed

ABSTRACT The purpose of this study was to examine, at a histologic level, the articular cartilage of the radiographically normal lateral compartment in knees with isolated medial and possibly patellofemoral osteoarthritis. Twenty patients with radiographic evidence of medial compartment osteoarthritis and a radiographically osteoarthritis-free lateral compartment underwent a tricompartmental total knee arthroplasty. The resected lateral femoral condyle and lateral tibial plateau were evaluated by a fellowship-trained musculoskeletal pathologist for the presence, or lack thereof, of osteoarthritis at a microscopic level. Both the tibia and femur showed evidence of mild osteoarthritis at a microscopic level. This study shows that in patients with radiographic evidence of medial osteoarthritis and a radiographically normal lateral compartment, there is mild osteoarthritis in the lateral compartment.

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