[Imaging of hip joint cartilage and its significance for the intertrochanteric transposition osteotomies in coxarthrosis].

The purpose of the study was to examine the accuracy of MRI in distinguishing between the cartilage of the femoral head and the acetabulum in vivo. In 20 healthy and 41 arthrotic hips an MRI was performed, using a special traction on the hips. With T1-weighted 3-dimensional gradient-echo sequence it is possible to distinguish between the high-signal femoral head and acetabular cartilage by having a low signal of the joint space. In the horizontal position of the phase encoding parameters a reduction of the chemical-shift artefact can be achieved mainly in the ventro-lateral areas. In addition it is possible to discriminate between four qualities of cartilage. The extent and localisation of degenerative cartilage in the hip joint can influence the indication of osteotomies for the hip joint.