[Total hip prosthesis at or beforeSO years old - Personal series of 188 cases]

215 cases operated on by one surgeon have been studied. Several prosthesis types, cemented and cementless were used. 188 cases could be analyzed correctly for this study, and rewied after a variable period, from 3 to 25 years.The year 90 being considered as a turning point in the evolution of our ideas, we divided this study into two parts : before 1990 (156 cases), and after 1990 (32 cases).Before 1990: The loosening rate is rather high: 46 reoperations in 156 cases, with a few being examined with a first intention, which represents a 29% rate. For the primary implantation, the rate is close to 19%. The 8th year seems to be a decivise one with many reoperations. Another rise in the number of revisions appears near the 13th year -several reoperations before 5 years correspond to technical weaknesses. - The reoperation rate is higher for cemented prostheses (34% of two pole cementing). - It is lower for cementless prostheses, especially for the femoral component, but the use of screwed rings led to failures. - The group of metal-metal prosthesis (type Mc Kee - Farrar) shows a higher loosening rate (around 50%), but it's the oldest range (more than 15 years). One the other hand, excellent results have been underlined in these series of «Mc Kee-Farrar» prosthesis after more than 20 years (this analyzed later). - The number of reoperations for the bearing shows a clear improvement thanks to the use of 22 mm or 28 mm heads, and of ceramics (Alumina), for the femoral head. Our short experience of alumina-alumina bearings with cup cementing was not favorable at the beginning of the 80's. - The loosening risk appeared all the more marked when the person was young. - The oldest prostheses (more than 15 years), were reoperated in 50% of the cases. 10 years later, the rate is near 30%. For 50 cases, after a 5 to 10 year period following the first operation, it is still close to 10%. It concerns the latest prostheses, that are sometimes cementless. After 1990: The study period is not long but the results of a short series of 32 cases are extremely positive. Only one prosthesis was cemented: the 31 other cases were operated on without cement. Cups were impacted respecting the acetabulum's elasticity. The femoral components were customised prostheses (Computer Assited Design), or ESOP type prostheses, since the Modularity allows good adaptation to the femur. Two revisions were necessary, but were not related to the type of the prosthesis.Hence, our ideas changed in terms of hip prosthesis implantation under 50 years and we think today that we should use: - cementless prostheses, - which allow a good stress distribution, at the femoral and acetabular fixation, - with an improved bearing surface material and size, - particulary easy to implant and possibly easy to take out, since it may be necessary to change so young and active patient's prostheses some day.