[Five years of experiences with the Antega cementless anatomical stem]

The aim of this study was to access the changes in bone tissue directly adjacent to the Antega cementless stem adaptive remodelling. This stem is corresponds in shape to the femoral bone canal. The clinical material comprised a group of 109 patients aged 32-62 years (average age: 45.5 years), who underwent total hip arthroplasty with the Antega stem. The target group consisted of 79 women (average age: 45.5 years) and 30 men (average age 49.1). The function of the hip was evaluated using Charnley's test. Densitometry was performed basing on computer analysis of the X-ray images taken in standard conditions in the antero-posterior projection. Changes in bone tissue density were assessed using Densitometria software. Bone remodelling directly adjacent to the implant was correlated to the Antega stem construction. Big changes in bone density in the area surrounding the stem with micropore coating may indicate that the intense bone remodelling processes are related to the osteoinductive properties of micropores and load-transmission to the bone in that area. The stem shaped in such a way to correspond to the anatomical shape of the femoral bone showed only a very small tendency to create stress shielding zones in its surrounding which may indicate that load transmission must closely resemble the physiological one.