Configuration of anchorage holes affects cemented fixation of the acetabular component in total hip replacement: an in vitro study.

Although surgical fixation techniques are major contributing factors to the survivorship of total hip replacements, they vary considerably among orthopaedic surgeons. We investigated the effect of the following configuration of anchorage holes on the stability of acetabular component fixation: 3 x 12 mm, 3 x 6 mm, 6 x 6 mm, and 12 x 6 mm. The reconstructed acetabulae were tested to torque failure, whilst being subjected to a compressive load of 2.1 KN. Higher torque to failure values were obtained for specimens with three 12 mm anchorage holes, compared with six or more 6 mm anchorage holes and were in line with our computer simulation results. We propose that the longevity of cemented total hip replacements could be improved by drilling a few large anchorage holes.