Uncemented and custom made hip prostheses in patients younger than 50 years.

One hundred and nine hip arthroplasties using custom cementless stems performed in patients 50 years of age or younger were reviewed after a minimum follow-up of two years. The etiologies included mainly major deformation of the upper femoral metaphysis such as CDH or after osteotomy and some cases of AVN or post-traumatic osteoarthritis. Two stems (1,8%) were revised and the overall clinical and radiographic failure rate was 5,5%. The intramedullary part of the custom stem (CT based) is able to match any kind of femoral metaphysis to provide stem stability, and the extramedullary part, the neck offset (CT based) can provide an optimal orientation of the prosthetic neck in the frontal and the horizontal planes, to restore physiological hip function.