[Polyethylene wear of the Optifix cementless acetabular component after 5 years]. / Usure du polyéthylène de la composante acétabulaire non cimentée Optifix à 5 ans.

The aim of this study is to review our experience with the Optifix porous-coated cementless acetabular component at an average 5 year follow-up. In a retrospective clinical investigation, the amount and rate of linear wear of the polyethylene of 26 cementless Optifix acetabular components implanted during a primary Hybrid (Spectron femoral component) total hip replacement in 24 patients, were determined by a comparison of the thicknesses of the cup as measured on the initial and most recent follow-up radiographs. The measurements were corrected for magnification error by direct measurement of the diameter of the femoral head on each radiograph according to the technique of Livermore et al. The mean duration of follow-up was 60 months (range, 48 to 73 months). Linear wear averaged 0.53 +/- 0.12 mm (0 to 2.28 mm) overall, with a mean rate of 0.11 +/- 0.02 mm (range 0 to 0.46 mm) per year p < 0.005. No osteolysis of the acetabulum was seen. None of the acetabular components migrated. Osteolysis of the endosteum of the femur was found in six hips. None of the femoral components subsided. In conclusion, wear of the polyethylene in this cup has not been previously reported, and is consistent with results published with other types of acetabular components.

[Mitchell's osteotomy in the treatment of hallux valgus]. / Ostéotomie de Mitchell dans le traitement de l'hallux valgus.

Ninety-one (91) Mitchell osteotomies on 63 patients (60 females and 3 males) were reviewed. The average follow-up was 40 months (min. 12, max. 70). The average age at the time of the surgery was 51 years (min. 20, max. 74). The presence of a apinful bunion justified the surgery in a majority of cases (92%). The clinical evaluation was done by an independent observer. Weight bearing X-rays of the feet were made in each case. The results show a satisfactory improvement of the pain in 92% of the cases. The patients were satisfied with the appearance of their foot in 93% of the cases. The average active articular range of motion was 47 degrees (min. 20 degrees, max. 120 degrees). The Das De scale showed 75% of excellent and good results. Twelve per cent (12%) of the patients presented residual metatarsalgia. We observed minor complications in 10 cases (11%). We report no cases of avascular necrosis, pseudarthrosis or infection. Clinico-radiological correlations were made. We obtained an average correction of 13 degrees (min. -5 degrees, max. 28 degrees) of the hallux valgus and 3.5 degrees (min. -7 degrees, max. 7 degrees) of the intermetatarsal angle. We recommend the Mitchell osteotomy as long as the indication criterias and the surgical technique are respected.

[Non-cemented self-locking total arthroplasty of the hip. Clinical and radiological results after three years]. / L'arthroplastie totale de la hanche non cimentée de type autobloquant. Résultats cliniques et radiologiques à trois ans.

We reviewed 47 patients who had fifty-one (51) primary, cementless biofit total hip arthroplasties (THA) implanted at Maisonneuve-Rosemont Hospital between 1986 and 1990. An independent observer rated the patients on the Harris Hip Score (HHS) by questionnaire, physical examination and radiological assessment. The average follow-up was 40 months. Twenty-two percent (22%) of the femoral components had been revised because of incapacitating pain, limping or a HHS inferior to 60. A little more than 20% of the unrevised prostheses had a mediocre result (HHS inferior to 70). There was no correlation between results and radiological signs of instability. The femoral component of the hip arthroplasty has a poor clinical performance which compares unfavourably with cemented prostheses.