The relationship between head-neck-shaft angle, calcar width, articular cartilage thickness and bone volume in arthrosis of the hip.

The thickness of articular cartilage and the macroscopic and morphometric characteristics of bone in the proximal femur were assessed in a group of 28 surgically-treated patients with advanced idiopathic osteoarthrosis, and compared with the findings in a group of 16 non-arthrotic femora obtained at autopsy. In arthrosis, the BMI was increased, cartilage thickness at two principal stress sites was found to be significantly reduced, and the femoral head-neck-shaft angle was reduced. The calcar width of the cortical bone in the femur was unchanged. Bone volume was increased at the principal compressive region and diminished at both of the tensile regions. Regression analysis showed that in arthrosis calcar width was dependent on BMI and bone volume in the medial principal compressive region of the proximal femur. Furthermore, the volume of bone medial to the greater trochanter was significantly correlated with BMI.