A new proposal for the radiographic evaluation of cartilage wasting in osteoarthritic hip joints

The aim of the present study was to analyze the distinct locations of minimum joint space width (mJSW) across the articular surface among osteoarthritic (OA) hip joints and to correlate the radiographic signs of cartilage wasting with clinical measures of hip function. Forty patients (mean age 67.6 years, range 50-82 years) with 80 hips showing varying degrees of OA were included in this study. For each hip, the Lequesne Index and the passive range of hip motion were evaluated and the mJSW was localized and measured in a. p. radiographs. Independent of the mJSW localization, the lateral, superior, and axial joint space width (JSW) were additionally measured in radiographs. Radiographic and clinical data were analysed and correlated with each other. mJSW was found in the superiolateral and axial parts of the OA hip joint in 90% of the cases. A significant correlation was found among almost all variables; however, the highest correlation (P < 0.01) existed between all functional variables and the sum of lateral, superior, and axial JSW (lsaJSW). As compared to the traditional mJSW, the results strongly recommend the measurement of lsaJSW, since this radiographic parameter represents well the weight-bearing areas of cartilage and shows a superior correlation with clinical evidences of hip disability.