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In order to avoid polyethylene wear observed in total hip replacement, an alumina-alumina combination has been used since 1977. The aim of this prospective study was to assess the results of an alumina-alumina total hip arthroplasty with a cementless press-fit plain alumina socket and a cemented titanium alloy stem with special attention for socket fixation because of previously encountered problems.Fifty-five patients (62 hips) were operated on between 1982 and 1990. The main parameter for inclusion was a high level activity demand. The bearing surfaces were a 32 mm alumina head articulating within the alumina socket. Mean follow-up was 6 years.Four revisions occurred in this series: 3 for aseptic loosenings of the socket and 1 for femoral head fracture. Considering acetabular revision for aseptic loosening as the end point, the survival rate was 93.2 % at six years and 78.8 % at six years when considering acetabular loosening as the end point. At a mean of 72.1 month-follow-up, 92.4 % of the remaining hips were graded as very good or good while 44.6 % showed radiolucent lines around the socket and 4 had migrated with no radio-clinical correlation. On the femoral side, there was no radiolucent line nor loosening, and the value of the colar calcar resorption was low (mean 0.4 mm). In all four revisions, the stem was left in place, and there was no bone loss, which allowed simple revisions.Thin radiolucent lines around bulk alumina press-fit sockets can be understood as a normal bone reaction to material as the Young's modulus is much higher. They do not necessarily signify mechanical failure of the fixation. However when considering the rate of acetabular loosening, an improvement of the alumina/bone interface is still required.

Alumina on alumina friction couple has proven its reliability in the field of total hip arthroplasty. However, loosening of the alumina socket has been responsible for most of the failures. An improvement of the bone/alumina interface could be achieved with the use of an osteconductive material as a coating on alumina. The aim of this study was to evaluate the osteconductive properties of two types of bioactive glasses as a coating on alumina substrates.Two types of coated implants (silicate glass coated alumina - AVSi, and phosphate glass coated alumina - AVP) were evaluated in a rabbit cancellous bone model. Pure alumina implants (A) were used as negative controls and bulk glasses (silicate - VSi and original 45S5, and phosphate glasses -VP) as negative controls. Sacrifices were performed at 3, 12 and 24 weeks. The interface evaluation included histomorphometry using an image analyzer.Silicate glasses demonstrated high osteoconductive properties. However, non mineralized osteoid tissue was the main tissue in contact with both coated implants and bulk phosphate glasses. This tissue covered over 70 p. 100 after 24 weeks of implantation, while it was never observed around pure alumina implants after 3 weeks.Amongst the hypotheses that could explain this mineralization inhibitory process, the one involving an Al(3+) glasses contamination from Al(2) O(3) is the likeliest. The high temperature coating procedure could be responsible for alumina transformation into a more soluble phase.

To avoid polyethylene wear observed in total hip replacement, an alumina-alumina combination has been used since 1977. The aim of this study is to report the results of a hybrid alumina-alumina total hip arthroplasty with a cementless press-fit bulk alumina socket and a cemented titanium alloy stem in 55 patients (62 hips) operated on between 1982 and 1990. The bearing surfaces were a 32-mm alumina head articulating within the alumina socket. Four failures occurred: 3 aseptic loosenings of the socket and 1 femoral head fracture. Considering aseptic loosening as the endpoint, the survival rate was 93.2% after 6 years. At a mean of 72.1 months' follow-up, 92.4% of the surviving hips were graded as very good or good using the Merle d'Aubigné-Postel hip score. Radiolucent lines were observed on the acetabular side in 68.1 of the hips. The future of this interface, which is probably fibrous, remains questionable. With the exception of 1 femoral head fracture, all revisions were related to failure of the bony fixation of the socket, and no problem was encountered related to the alumina-alumina friction coupling. Alumina sockets with other types of cementless fixation have therefore been designed and are presently under clinical investigation.

Sixty-three total knee replacements were performed after a failed tibial osteotomy. The goal of this study was to compare the perioperative problems and the outcome of this group of patients (study group) to a group of patients with primary arthroplasties matched for age, gender, length of follow-up, weight, and preoperative Charnley class. Operative problems were more frequently encountered in the study group, with 7 tibial tubercle elevations and 15 lateral retinaculum releases needed, whereas lateral retinaculum release was necessary for only 1 knee in the control group. Outcome was assessed using both the International Knee Society (IKS) scoring system and Hospital for Special Surgery (HSS) knee score. The follow-up period averaged 4.6 years. The IKS score of the control group was significantly higher, averaging 80.9 +/- 13.8, whereas it was 74.4 +/- 14.8 for the study group (P = .0001). Among the parameters included in the knee score, only pain was significantly different with the control group (P = .03). The IKS function score and the HSS score were not statistically different. Conversion of a failed tibial osteotomy is a technically demanding procedure. Careful preoperative planning is needed. Results, especially on pain, appeared to be inferior to those for primary arthroplasties.

A new case of bilateral, diaphyseal hyperostosis of the leg bones is reported. Strictly unilateral symptoms appeared when the patient was 35 years old consisting of unbearable pain in the middle section of the antero-medial side of the left leg. Diagnosis was based on X-rays and a pre-operative bone scintiscan, showing localised hyperfixation opposite the pain site. Preoperative locating using a radioactive marker enabled circumscribed but complete excision of the hyperfixation site. This diagnosis was confirmed by the pathologist examination. The patient, who experienced immediate relief after surgery, has remained pain-free for one year to date. The relationship between this case and Camurati-Engelmann disease (diaphyseal dysplasia) is discussed.