Objective

Cement thickness of at least 2 mm is generally associated with more favorable results for the femoral component in cemented hip arthroplasty. However, French-designed stems have shown favorable outcomes even with thin cement mantle. The biomechanical behaviors of a French stem, Charnley-Marcel-Kerboull (CMK) and cement were researched in this study.

Introduction

Excellent long-term survival rates associated with the absence of stem subsidence have been achieved with total hip arthroplasty (THA) using femoral components cemented line-to-line (“French Paradox”). Recently, short stems have been introduced in order to preserve diaphyseal bone and to accommodate to minimal invasive THA and a variety of clinical situations. The aim of the current study was to quantify the rotational and tilting stability of a Kerboull stem of varying length after line-to-line cementation using a validated in-vitro model.

Introduction

The purpose of this study was to evaluate the in vivo migration patterns of a polished femoral component cemented line-to-line using EBRA –FCA.

We present a new technique for TKA implantation which utilizes patient-specific femoral and tibial positioning guides developed from MRI to offer an individualized approach to total knee replacement.

This is a prospective non controlled study which aims to analyse the precision of this technique, its advantages and inconvenients in comparison with the conventional instrumented technique.

Introduction: The purpose of this study was to report on the minimal 10-year followup results of a prospective randomized and a historical series of low friction cemented hip arthroplasties according to the surface finish of the femoral implant.

Patients and Methods: The prospective randomized series included 284 patients (310 hips) with a mean age of 64.1 years. Among these 310 hips, the femoral component had a highly polished surface (Ra = 0.04 micron, MKIII, Stryker) in 165 hips, and a matte surface finish (Ra = 1.7 microns, CMK3, Vector Orthopedique) in the remaining 145 hips. The historical series that was operated by the sames surgeons according to the same surgical technique included 111 patients (123 hips) with a satin finish femoral component (Ra = 0.9 micron, CMK2, Sanortho). Clinical results were rated according to the Merle d’Aubigne hip score. Radiologic analysis was performed according to the criteria of Barrack et al. for the definition of loosening. Moreover, a survival analysis according to the actuarial method was conducted.

Results: At the minimum 10-year follow-up evaluation, 43 patients (48 hips) were lost to follow-up (0.3 to 8.7 years), 80 patients (83 hips) were deceased (0.1 to 13.6 years), 26 patients had revision of either or both components (0.9 to 15.9 years), and 246 patients (276 hips) were alive and had not been revised after a mean 12.3 ± 1.9 years (10 to 16 years). Radiologic loosening of the femoral component, including revision, occured in one, four, and 15 hips for the polished, stain, and matte groups, respectively. The survival rate at 13 years of the femoral component, using loosening as the end point, was 97.3 ± 2.6% (95% CI, 92.2 to 100%), 97.1 ± 2.1% (95% CI, 93 to 100%), and 78.9 ± 5.8% (95% CI, 67.6 to 90.3%) for polished, satin, and matte stems, respectively.

Discussion: This study demonstrated that cement fixation of a femoral component was more reliable in the long term with a polished or satin surface finish. Based upon our results and the review of the literature, we recommend abondoning the use of cemented stems with a surface roughness greater than 1 micron.

Purpose: The purpose of this retrospective study was to evaluate the clinical and radiological results of Charnley-Keroboull total hip arthroplasty performed in patients aged less than 50 years. We searched for factors which might affect wear and sustained fixation.

Material and methods: Among the 2,804 arthroplasties performed in patients aged less than 50 years between 1975 and 1995, we selected randomly 287 (10% of the annual operations). These prostheses were implanted in 222 patients (144 women and 78 men), mean age 40.1±8 years (15–50). All of the arthroplasties were inserted via a transtrochanteric approach. Charnley-Kerboull implants were cemented in all patients using a metal polyethylene bearing. Functional outcome was assessed with the Postel-Merle-d’Aubigné score. Cup wear was measured with the Chevrot technique. The actuarial method was used to calculate prosthesis survival.

Results: At last follow-up, 155 patients (210 hips) were living and had not had a revision procedure at mean 16.1±4.6 years, 23 patients (25 hips) required revision of the acetabular or femoral element, ten patients (10 hips) had died, and 34 patients (42 hips) were lost to follow-up. The mean preoperative functional score was 9.6±2.5 (9–15) versus 17.2±0.8 (9–18) at last follow-up (Wilcoxon rank test p< 0.001). For the acetabular element, there was certain loosening in 15 hips and possible loosening in 24. For the femoral element, loosening was certain for 12 implants and possible for four. Twentyfive hips required revision, including 17 for aseptic loosening. Mean wear was 0.12±0.21 mm (0–2.23). Among the 287 hips, 196 had wear measured at less than 0.1 mm/yr (mean 0.02 mm/yr). Mean overall implant survival, defining revision as failure, was 85.4±5.0% at twenty years (95%CI 78.4–92.4). Among the factors tested, only abnormally rapid wear (> 0.1 mm/yr) was predictive of failure.

Discussion: The results of this series allow us to conclude that total hip arthroplasty using a Charnley-Kerboull implant remains the best solution for young patients in terms of implant survival.

Purpose: Certain authors have indicated that the primum movens of loosening of cemented femoral stems is related to the decohesion of the cement implant interface. Under such conditions, improvement in this interface was attempted with the development of a rough surface for the femoral piece. The purpose of this retrospective analysis was to evaluate results a minimum ten years follow-up in a consecutive series of total hip arthroplasties comparing types of femoral implant surfaces.

Material and methods: Between January 1988 and December 1989, 311 THA were implanted in 286 patients aged 63.6±11.8 years (26–91). All implantations were performed via the transtrochanteric approach by two senior surgeons. Two types of femoral implant were used: 166 non-polished pieces with a round section Ra = 3 mm (CMK3, Vector Orthopédique) and 145 polished pieces with a quadrangular section Ra = 0.4 mm (MKIII, Stryker Howmedica). The preoperative data were comparable for the two groups. Functional results were assessed with the Postel Merle d’Aubigné score (PMA). Actuarial survival curves were plotted.

Results: At minimum ten years follow-up, 187 patients (204 hips) were living and had not required revision at mean follow-up of 11.7±2.5 years (10–14), 15 patients (15 hips) had revision of the acetabular and/or femoral element, 54 patients (58 hips) had died, and 30 patients (34 hips) were lost to follow-up. The mean preoperative function score was 11.2±2.5 (4–16) versus 17.5±0.5 (10–18) at last follow-up (Wilcoxon rank test, p< 0.001). Cumulative survival at 13 years, taking radiographic loosening of the femoral piece as the endpoint, was 78.9±5.8% (95%CI 67.6–90.3%) for unpolished implants versus 97.3±2.6 (95%CI 92.2–100) for polished implants. The difference was significantly different (p< 0.001).

Discussion: The results of this analysis indicate that radiographic survival of unpolished cemented femoral pieces is significant inferior compared with polished pieces. The increased adherence of the femoral cement is probably the cause of increased shear stress at the bone-cement interface. The respective influence of section and surface remain to be determined.

Aims: The purpose of this prospective randomized study was to report on the minimal 10-year follow-up results of a consecutive series of cemented total hip arthroplasty according to the surface finish of the femoral implant. Methods: Between January 1988 and December 1989, 311 total hip arthroplasties were performed in 286 patients. Implants were of Charnley Kerboull design combining a 22.2-mm femoral head and an all-polyethylene socket. The cemented femoral implant was available in two configurations: polished (Ra = 0.4 μm) and matte (Ra = 3 μm). The polished stem (MK III, Stryker Howmedica) was implanted in 166 hips, and the matte stem (CMK 3, Vecteur Orthopedic) in the remaining 145. The mean age of the patients was 63.6 years. Results: At the minimum 10-year follow-up evaluation, 187 patients (204 hips) were still alive and had not been revised at a mean of 11.7 years (10–14 years), 15 patients (15 hips) had been revised, 54 patients (58 hips) had died from unrelated causes, and 30 patients (34 hips) were lost to follow-up. The mean d’Aubigné hip score was 17.7 ± 0.3 at the latest follow-up. The survival rate at 13 years, using radiologic loosening as the end-point, was 97.3 ± 2.6% (95% confidence interval, 92.2 to 100%) for polished stems, versus 78.9 ± 5.8% (95% confidence interval, 67.6 to 90.3%) for matte stems (log-rank test, p = 0.0001). Conclusions: This study demonstrated that cemented fixation of femoral stems was significantly more reliable in the long-term with a polished surface.

Aims: The aim of this open prospective study was to evaluate the minimum 2-year follow-up outcome of a consecutive series of low friction total hip arthroplasties combining zirconia on polyethylene. Methods: Between January 1997 and June 1999 fifty-five total hip arthroplasties were performed in 51 patients. The mean age was 52.2 ± 12 years. The 22.2-mm femoral head made of zirconia ceramic was secured to the femoral component through a Morse taper that had an angle of 11°25 for 27 hips and 5°40 for 33 hips. All prostheses were of Charnley-Kerboull design. Clinical results were evaluated according to the Merle d’Aubigné hip score. Wear of the acetabular component and periprosthetic osteolysis was measured on serial radiographs of the pelvis. Results: The mean follow-up of the series was 32 months (24 to 48 months). No patient was lost to follow-up. The mean functional hip score significantly increased from 12.2 ± 2.6 preoperatively to 17.8 ± 0.2 at the latest follow-up (paired Student’s t test, p < 0.0001). None of the acetabular or femoral component had migrated. Wear of the socket was always undetectable on plain radiographs. However, lytic endosteal lesions of the calcar were observed in 19 of the 55 arthroplasties (34.5%). These lytic lesions appeared between the first and second postoperative year. Conclusions: Early calcar osteolysis observed in this study can be related to either run-in wear or to preliminary severe wear. The authors do not recommend further use of zirconia ceramic until long-term follow-up studies are available.

Purpose: New surfaces have been developed to reduce polyethylene wear. The zircone ceramic surface appears to have a theoretical advantage due to its interesting tribologic properties. The purpose of this prospective study was to assess clinical and radiological outcome at a minimal two years follow-up in a consecutive series of total hip arthroplasties using the polyethylene zircone junction.

Material and methods: La series included 56 total hip arthroplasties performed in 49 patients (30 women and 19 men), mean age 52.2 ± 12 years (25–76). Primary degenerative hip disease was the aetiology in 43% of the cases, dysplasia in 27%. The femoral component was made of 316L steel with a 11°25 Morse cone for 27 hips and a 5°40 cone for 29 hips. The femoral head measured 22.2 mm and was made of polycrystaline zircone ceramic stabilised in the tragonal form with yttrium (Y-TZP). All the arthroplasties were performed via transtrochanteric access using cemented Charnley-Kerboull implants. Clinical outcome was assessed with the Merle-d’Aubigné score. Classical landmarks on the AP pelvis views were used to assess implant migration. Cup wear was measured using the Livermore method. Actuarial survival curves were plotted.

Results: Mean follow-up was 32 months (24–48). None of the patients were lost to follow-up. The mean functional score at last follow-up was 17.8±0.2 (16–18) versus 12.2±2.6 before arthroplasty (Student t test for paired variables, p < 0.0001). No cases of migration of the femoral or acetabular component were observed. Acetabular wear was always less than the precision of the measurement method. Osteolytic lesions were however observed as endosteal defects in the Merkel region measuring less than 1 cm2, observed in 18 out of the 56 hips (32%). These osteolytic lesions generally appeared between the first and second year and did not appear to progress.

Discussion: Osteolysis in the Merkel region appeared early for one third of the hips, despite the absence of cup polyethylene wear. It would be reasonable to be prudent when using zirone ceramic heads. We are continuing our close follow-up of this group of patients. In addition, measurements of wear and migration are being made using the EBRA method.

Purpose of the study: Extensive loss of femoral bone subsequent to implant loosening raises an unsolved problem. The purpose of this work was to examine mid-term results of 18 iterative total hip arthroplasties with femoral reconstruction using massive allografts performed between 1986 and 1997.

Materials and methods: Using the Vives classification, the femoral bone lesions were grade 3 (n = 2) and grade 4 (n = 16). The reconstruction was achieved with radiated massive allografts measuring 11 to 35 cm implanted in a split host femur. Charnley-Kerboull implants with a long stem were cemented in the reconstructed femurs.

Results: Mean follow-up was 4 years 10 months (range 2 to 9 years). Nine complications in 7 hips were observed: 6 trochanter nonunions, two recurrent prosthesis dislocations and 1 femoral fracture. At last follow-up, the functional result was excellent or very good in 12 hips (Merle d’Aubigné classification). A stable fixation persisted for 15 implants and 3 had loosened. Graft-host femur consolidation was achieved in all cases except 1. There were 3 cases with extensive resorption of the graft including 2 associated with loosening of the femoral component.

Discussion: Reconstruction of the femur after extensive bone loss using a massive allograft appears to be a useful method for restoring bone tissue and providing immediate mechanical support for the femur.