VALIDITY OF ECHOGRAPHIC EVALUATION OF CARTILAGE IN GONARTHROSIS - PRELIMINARY-REPORT

We studied an echographic technique by which precise reproducible measurements of articular cartilage thickness of the knee is possible. Two groups of individuals were studied: a group of 18 patients with gonarthrosis and a control group of 10 normal individuals. The group of 18 patients with gonarthrosis was studied by ultrasound (US) before knee prosthesis surgery. The cartilage thickness was measured within the weight-bearing area. US re-evaluation and histological measurements were made on the pathological specimen following the operation. Results of pre- and post-operative US data were compared with histological data. A good correlation between these measurements was found [P(t)>10%]. In order to have comparative reference values of the articular cartilage within the weight-bearing area of the femoral trochlea a group of 10 control subjects was also studied with US as above. We found that the articular cartilage thickness of the femoral trochlea in the weight-bearing area has a mean of 2.2 +/- 0.3 mm for the lateral condyle and 2.3 +/- 0.2 mm for the medial condyle. The intra-observer and inter-observer difference in measurements was evaluated with Student's t-test. Our data demonstrate that US measurements of articular cartilage thickness of femoral condyles is a sensitive and reproducible technique which permits early diagnosis and management of knee arthropathy as well as quantification of cartilage damage.