Source of the study: University of Auckland, Auckland, New Zealand and University of Otago, Christchurch, New Zealand. Outcomes following knee arthroplasty are typically defined as implant survivorship at defined timepoints, or revision incidence over time. These estimates are difficult to conceptualise, and lack context for younger patients with more remaining years of life. We therefore aimed to determine a ‘lifetime’ risk of revision as a more useful metric for total (TKA) and unicompartmental knee arthroplasty (UKA). The New Zealand Joint Registry was used to identify 96,497 primary TKAs and 13,481 primary UKAs performed between 1999 and 2019. Patient mortality and revision incidence were also extracted. Estimates of lifetime risk were calculated using an actuarial lifetable method. The estimates were stratified by age and gender. Reasons for revision were categorised using previously published standardised definitions. The lifetime risk of UKA revision was two-fold higher than TKA across all age groups (range 3.7-40.4% UKA, 1.6-22.4% TKA). Revision risk was higher for males with TKA (range 3.4%-25.2% males, 1.1%-20% females), but higher for females with UKA (range 4.3%-43.4% vs. 2.9%-37.4% for males). Revision due to infections were higher for TKA (1.5% males, 0.7% females) compared with UKA (0.4% males, 0.1% females). The increased risk in younger UKA patients was associated with higher incidence of aseptic loosening (UKA 2%, TKA 1%) and ‘unexplained pain’ (UKA 2%, TKA 0.2%). The risk for UKA was two-fold higher than TKA, and this was partially explained by a higher proportion of revisions due to ‘unexplained pain’. For TKA, males had higher risk of revision, in contrast to UKA where females had higher risk; this gender difference was associated with higher incidence of infections with TKA. Younger age, gender and higher ASA status were also associated with increased lifetime risk of UKA revision. Lifetime risk of revision can provide a meaningful measure of arthroplasty outcomes to aid patient counselling

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: Among 115 cemented patellofemoral Bechtol-Blazina prostheses implanted between 1974 and 1991, we reviewed 59 knees in 41 women and nine men (nine bilateral implants). Material and methods: Mean patient age was 60 years and mean follow-up was ten years (6–16). The main indication was primary degenerative disease (82%) followed by chondrocalcinosis (6%), chondromalacia (7%) and secondary degeneration (5%). A previous procedure had been performed on 18 knees (14 patellofemoral and four femorotibial). Associated procedures were tubercle translocation (n=15), tibial osteotomy (n=2), and tension of the medial wing (n=1). The International Knee Society score was noted. Results: According to the IKS, outcome was good or excellent in 91% of the knees and insufficient in 9% (knee score and function score). Mean ten-year survival determined with the actuarial method was 84.4%. It fell from 91.1% to 75.5% between the ninth and eleventh year due to femorotibial deterioration. There were no cases of phlebitis, infection or prosthetic loosening. Causes of failure were predominantly femorotibial (eight degradations) rather than femoropatellar (two snaps and three painful syndromes involving the lateral parapatellar area). Thirteen reoperations were necessary: tri-compartmental arthroplasty (n=8), modification of the trochlear orientation (n=1), release of the lateral patellar wing (n=3), demaquetisation (n=1). Total or nearly total pain relief was achieved for 80% of the knees. The mean flexion angle was 123° and stair climbing was considered normal in 91% of the patients. All knees were stable. Radiographically, there were six cases of polyethylene remodelling and one case of wear associated with major femorotibial deterioration. This absence of significant wear was, in our opinion, essentially due to the absence of a metal-backed patellar insert. Discussion: The following indications can be retained on the basis of this series: the ideal indication is isolated patellofemoral osteoarthritis with dysplasia, relative indications are advanced-stage patellofemoral osteoarthritis with axial deviation having no clinical or radiographic (tangent view) impact. In this case, the patellofemoral implant allows postponing insertion of a tricompartmental prosthesis in middle-aged patients. Contraindications are patellar chondromalacia, chondrocalcinosis, low patella, and presence of associated femorotibial degradation. Conclusion: The long-term clinical and radiographic results after patellofemoral arthroplasty make this procedure the treatment of choice for isolated and advanced-stage patellofemoral osteoarthritis on a normally axed limb when a conservative procedure cannot be performed or has failed. It provides effective pain relief and good knee stability. The operation is difficult and must use congruent implants to avoid the problem of prosthetic instability and patellar snaps

The topic of this study was to research the survival rate of ATLAS hip prosthesis (acetabular cup) performed by one operating surgeon only and with a minimum of 10 years follow up. Material and method: The ATLAS cup was hemispheric, in titanium alloy TA6V4, with a thin layer (2.5mm). It had a large central orifice as well as a radial slot allowing a certain elasticity enabling a pressfit impaction. Between January 1989 and December 1995, 297 ATLAS were implanted in the Clinique Saint André of Reims, 171 ATLAS II non hydroxyapatite coated and 126 ATLAS III hydroxyapatite coated. There were 176 women (59,2%) and 121 men (40,8%). The average age was 66 (20 to 94). Each patient was contacted by phone to find out if the prosthesis was still in place or whether a new operation had been performed. For the deceased patients, the family or the usual doctor were contacted by phone to answer the question with a maximum of details. The non-parametric survival rates were performed using the actuarial method according to Kaplan-Meier. The results were given with a reliability rate of 95%. The PRISM program was used. RESULTS: On the 1st of January 2006, out of the 297 patients present at the start, 38 patients (12,8%) could not be contacted, 70 patients (23,5%) had died, 35 were reviewed and 120 answered the phone inquiry. 32 patients had undergone a revision: 23 due to the cup: there were 15 cases of wear of the polyethylene, 4 osteolysis, 3 cases of recurring dislocation and a secondary tilt of the cup, 5 cases of acetabular and femoral revision for 4 femoral loosening (change of cup by principal) and 4 cases of revision of the femoral components only. The survival rate of the global series of 297 ATLAS (coated and non coated with hydroxyapatite) taking into consideration only the revisions due to the acetabular cup (wear of polyethylene, wrong position) was evaluated at 90% after 10 years and 85,5% after 15 years. The results were better for the ATLAS III coated in hydroxyapatite: 92,3% after 10 years and 88,4% after 14 years, which confirms the advantages of this surface treatment. In this series, the revision rate for wear of the polyethylene was less important (3%). With a maximum of 17 years follow up no mobilisation of the insert in the cup had been observed and no metallosis. Conclusion: The survival rate of the global series of 297 ATLAS (coated and non coated with hydroxyapatite), taking into consideration only the revisions due to the cup (wear of the polyethylene, wrong position) was of 90% after 10 years and 85,5% after 15 years. The rate was higher for the ATLAS III coated with hydroxyapatite: 92,3% after 10 years and 88,4 % after 14 years, which confirmed the advantages of this surface treatment