Comparative analysis of two different types of alumina-alumina hip prosthesis retrieved for aseptic loosening.

We compared and quantified the modes of failure and patterns of wear of 11 Mittelmeier and 11 Ceraver-Ostal retrieved alumina-alumina hip prostheses with reference to the corresponding clinical and radiological histories. Macroscopic wear was assessed using a three-dimensional co-ordinate measuring machine. Talysurf contacting profilometry was used to measure surface roughness on a microscopic scale and SEM to determine mechanisms of wear at the submicron level. The components were classified into one of three categories of wear: low (no visible/measurable wear), stripe (elliptical wear stripe on the heads and larger worn areas on the cups) and severe (macroscopic wear, large volumes of material lost). Overall, the volumetric wear of the alumina-alumina prostheses was substantially less than the widely used metal and ceramic-on-polyethylene combinations. By identifying and eliminating the factors which accelerate wear, it is expected that the lifetime of these devices can be further increased.

Posterolateral release for idiopathic clubfoot: review of 18 patients.

The authors treated and reviewed 18 patients with 26 idiopathic clubfeet by posterolateral release and elongation of the tendo Achillis at a mean age of 14.6 months (range 7-32 months). The mean follow-up of these patients was 43 months (range 6- 100 months). Function, appearance, and pain were studied. The mean ankle dorsiflexion was 20 degrees at the time of review. In all but one case, the hindfoot equinus had been well corrected. Subtalar movement was 75% of normal in six feet, and 50% of normal in 16 feet. Revision of the posterolateral release combined with anteromedial release was carried out for six patients with residual hindfoot varus and forefoot adduction at an average of 13.5 months following the initial procedure. In one patient, the deformity was overcorrected, but the results of the rest of the revision operations were otherwise good. No skin or wound problems were observed in this series. In conclusion, of 26 feet undergoing posterolateral release for severe clubfoot, 70% had a satisfactory result. Six feet required further surgery (reoperation rate of 23.1%).

A 4- to 10-year follow-up study of the Tricon-M noncemented total knee replacement.

This study reviews the clinical and radiographic results of 207 consecutive noncemented Tricon-M (Smith & Nephew Inc, Memphis, Tenn) total knee replacements (TKRs) in 189 patients. The patella was surfaced in 119 cases, and mean follow-up was 8 years (range: 4-10 years). At final follow-up, mean Hospital for Special Surgery score improved 45 points in 187 cases. Survivorship, with failure defined as the need for revision, was 98% at 4 years, 97% at 7 years, 94% at 8 years, and 90% at 10 years. Twenty-one (11.3%) patients went on to revision. Results for overweight and obese patients did not differ significantly from normal-weight patients. The noncemented Tricon-M TKR prosthesis yields acceptable results; however, patella surfacing and the use of a tibial polyethylene insert > or = 12 mm thick are recommended.

Cementless ceramic hip arthroplasties in patients less than 30 years old.

Twenty-six cementless ceramic hip arthroplasties were performed in 22 patients with an average age of 24 years (range, 17-30 years) at the time of operation. One patient was lost to follow-up evaluation. Twenty-one patients (25 hips) were reviewed with an average follow-up period of 6.5 years (range, 4-13 years). Two hips had to undergo revision of the ceramic acetabular components because of fractures in the upper part of the cup in both. One further hip was explored because of persistent wound discharge, but a mass of indurated tissue was removed and there was no evidence of deep infection. No organisms were grown from the samples taken during operation. Harris hip scores were good to excellent in 64%, fair in 16%, and poor in 20% of cases. There was no or slight pain in 14 (56%), mild pain in 7 (28%), and moderate pain in 4 (16%) hips. Apart from the two sockets revised, progressive radiolucent lines were seen in five cups (20%) and significant vertical migration was present in nine cups (36%) with an average migration of 1.3 mm/y. In total, acetabular changes were observed in 11 cases (44%). Femoral stem subsidence of between 3 and 6 mm was seen in five cases (20%). The total number of hips showing loosening of one or both components was five (20%). Overall radiographic changes (migration and loosening) in one or both components were present in 13 hips (54%).

Long-term results of minimally invasive lumbar disc surgery.

Long-term results of minimally invasive primary lumbar discectomies are processed. The operation was fairly simple and inexpensive, with reduced hospital stay (24 hours). The subsequent rehabilitation was compared to the more extensive procedures. The Oswestry-style questionnaires were found to be gratifying with a high percentage (80.9%) of patients, who returned to normal or nearly normal lives. No significant difference was found with published results of microdiscectomy.

The three-dimensional anatomy of the proximal femur in Perthes' disease.

A new method of recording the three-dimensional anatomy of the proximal femur from a single anteroposterior radiograph is described. This technique shows that in Perthes' disease the femoral head and neck are in significant anteversion and true varus. This anatomical configuration may be important in the pathogenesis and treatment of this disorder.

The treatment of congenital vertical talus.

Operative correction of congenital vertical talus in nine feet in six patients is described. The operation consists of the comprehensive lengthening of the tendons in the foot and full peritalar release without excision of the navicular; it is performed through a dorsal transverse incision.

Hip dysplasia without dislocation in one-year-old boys.

Six boys were examined during the second year of life, each with symptoms in one hip. The affected femoral capital epiphysis was smaller or more irregular (or both) than that of the unaffected hip but was neither subluxed nor dislocated. The subsequent radiographs revealed changes similar to those in severe Perthes' disease. Nevertheless, we give reasons for believing that this disorder in boys under two years of age should be distinguished from Perthes' disease.

Rotational displacement of the lower tibial epiphysis due to trauma.

A rare form of injury to the distal tibial growth plate is described. Only two patients with such an injury have been reported previously. The injury, rotational displacement of the distal tibial epiphysis with posterior displacement of the fibula but without fracture, can be reduced easily and appears to have no lasting ill-effects.