Acetabular loosening in cemented arthroplasty of the hip. Relationship with atrophic arthrosis.

Between 1976 and 1982, 126 low friction arthroplasties were implanted in primary arthrosis of the hip. The displacement rate or acetabular loosening related to the type osteoblastic response to the disease were studied. The hips were subdivided into three groups based on the radiographical aspect observed prior to implant. The atrophic type revealed a greater incidence for this type of complication (27.3%) whereas cases classified as normotrophic revealed a 5.6% incidence and hypertrophic a 6.1% incidence. The authors conclude that the type of bone response in primary arthrosis plays an important role in the occurrence of acetabular mobilization, and that osteoblastic response may be considered to be of prognostic value together with other well-known factors in the evolution of this type arthroplasty.