Nationwide partial knee replacement uptake is influenced by volume and supplier--A Dutch arthroplasty register study.

BACKGROUND: Despite the established advantages of partial knee replacements (PKR), their usage remains limited. We investigated the effect of hospital knee arthroplasty (KA) volume and the availability of a frequently used PKR by the total KA supplier on the use of PKRs in a hospital. METHODS: A total of 190,204 total knee replacements (TKR) and 18,134 PKRs were identified in the Dutch Arthroplasty Register (LROI) from 2007 to 2016. For each hospital we determined the annual absolute KA volume (TKR+PKR) into quartiles (<103, 103-197, 197-292, >292 knee replacements/year), and determined whether the TKR supplier provided a frequently used PKR. Hospitals were divided in routine PKR users (≥13 PKRs/year) or occasional/non PKR users (<13 PKRs/year). Based on these parameters, the effect of total KA volume and supplier on PKR usage was investigated, using chi-square tests. Logistic regression analysis was performed to evaluate the influence of the combination of these factors. RESULTS: In the lowest volume group, around 15% of the hospitals used PKRs, compared to 75% in the highest volume group. Having a TKR supplier that also provides a frequently used PKR resulted in a higher likelihood of performing PKR, especially in low volume hospitals. CONCLUSIONS: Hospitals' total KA volume and the availability of a frequently used PKR appear to influence the use of PKR.

The Accolade TMZF stem fulfils the demands of modern stem design: Minimum 5-year survival in a cohort of 937 patients.

PURPOSE: Modern hip stem design includes a prosthesis that has a predictable outcome in all total hip arthroplasty (THA) patients, regardless of approach, surgeon or patient characteristics. Introduction without a learning curve and, in cases of problems, the possibility for a simple revision are other prerequisites. The purpose of this study is to evaluate whether the Accolade TMZF stem (Stryker Orthopedics, Mahwah, New Jersey, USA) is suitable to fulfil these demands. We report our mid-term survival of the Accolade TMZF hip stem in all patients from the first implantation at our institute. METHODS: From the start of using the Accolade TMZF stem (March 2009) until February 2011, 937 THA were performed by 12 surgeons using a posterolateral or anterolateral approach. Survival of the stem was calculated using Kaplan-Meier analysis. Effect of approach, patient age and comorbidity were analysed with a Cox proportional hazards' model. The learning effect was determined by comparing the number of revisions in the surgeons' first 20 THAs with their next 30 THAs and the subsequent THAs. RESULTS: At 5 years, cumulative stem survival was 97.9% based on revisions for all reasons and 98.8% with aseptic loosening as endpoint. We found no effect of surgical approach, patient age or comorbidity on stem survival. No learning effect was found. CONCLUSION: The Accolade TMZF stem fulfilled the demands of modern stem design.