Bone support of a custom triflange acetabular component over time.

Aims: To investigate the extent of bone development around the scaffold of custom triflange acetabular components (CTACs) over time. Methods: We performed a single-centre historical prospective cohort study, including all patients with revision THA using the aMace CTAC between January 2017 and March 2021. A total of 18 patients (18 CTACs) were included. Models of the hemipelvis and the scaffold component of the CTACs were created by segmentation of CT scans. The CT scans were performed immediately postoperatively and at least one year after surgery. The amount of bone in contact with the scaffold was analyzed at both times, and the difference was calculated. Results: The mean time between the implantation and the second CT scan was two years (1 to 5). The mean age of the patients during CTAC implantation was 75 years (60 to 92). The mean scaffold-bone contact area increased from 16% (SD 12.6) to 28% (SD 11.9). The mean scaffold-bone distance decreased from a mean of 6.5 mm (SD 2.0) to 5.5 mm (SD 1.6). None of the CTACs were revised or radiologically loose. Conclusion: There was a statistically significant increase of scaffold-bone contact area over time, but the total contact area of the scaffold in relation to the acetabular bone remained relatively low. As all implants remained well fixed, the question remains to what extend the scaffold contributes to the observed stability, in relation to the screws. A future design implication might be an elimination of the bulky scaffold component. This design modification would reduce production costs and may optimize the primary fit of the implant.

Long-term follow-up of 96 patients younger than age 25 with 119 primary cemented total hip arthroplasties.

BACKGROUND AND PURPOSE: Long-term follow-up of young patients following cemented primary THA is scarce. Therefore, we analyzed the survival of all consecutive primary THAs in patients under 25 years performed at our institute. PATIENTS AND METHODS: All primary THAs performed in patients younger than 25 years in our tertiary care institute between 1988 and 2015 were included (n = 119). Cemented fixation was used in all patients. In the case of acetabular bone deficiencies, reconstruction was performed using impaction bone grafting (IBG). We used Kaplan-Meier analysis to determine the survival of the primary THA with endpoints revision for any reason and aseptic loosening. RESULTS: The mean age at the primary THA was 20 years. The most prevalent diagnosis was avascular necrosis (31%). The mean follow-up of the primary THA was 11 years (range 0-32). 2 patients (2 hips) were lost to follow-up. 16 revisions were registered. The survival of any component for endpoint revision for any reason was estimated at 92% (95% confidence interval [CI] 84-96) and 81% (CI 67-90) at 10- and 15-year follow-up, respectively. The survival of any component for endpoint revision for aseptic loosening was 99% (CI 93-100) and 88% (CI 71-95) at 10 and 15 years, respectively. 3 hips were revised due to infection. CONCLUSION: Favorable long-term outcomes of primary THA in very young patients can be obtained using cemented fixation and IBG.

Thirty years of experience with instrumented femoral impaction bone grafting and a cemented polished Exeter stem : a prospective cohort study of 208 revision arthroplasties performed between 1991 and 2007.

AIMS: The aim of this study is to report the long-term outcomes of instrumented femoral revisions with impaction allograft bone grafting (IBG) using the X-change femoral revision system at 30 years after introduction of the technique. METHODS: We updated the outcomes of our previous study, based on 208 consecutive revisions using IBG and the X-change femoral revision system in combination with a cemented polished stem, performed in our tertiary care institute between 1991 and 2007. Kaplan-Meier survival analyses were used to determine the survival rate of the revisions with endpoint revision for any reason and aseptic loosening. Secondary outcomes were radiological loosening and patient-reported outcome measures. RESULTS: Mean age at revision total hip arthroplasty (THA) was 64.9 years (30 to 86). The most prevalent diagnosis for the femoral revision was aseptic loosening. At review in May 2021, 81 patients (85 hips) were still alive and 118 patients (120 hips; 58%) had died. Three patients (3 hips; 1%) were lost to follow-up at 11, 15, and 16 years after surgery, respectively. Data of all deceased and lost patients were included until final follow-up. The mean follow-up was 13.4 years (0 to 28). During the follow-up, 22 re-revisions were performed. The most common reason for re-revision was infection (n = 12; 54%). The survival with endpoint re-revision for any reason was 86% (95% confidence interval (CI) 79 to 91) at 20 years and 74% (95% CI 43 to 89) at 25 years after surgery. The survival for endpoint re-revision for aseptic loosening was 97% (95% CI 91 to 99) after both 20 and 25 years. CONCLUSION: We conclude that femoral IBG is a valuable technique that can reconstitute femoral bone loss in the long term. After 25 years of follow-up, few re-revisions for aseptic loosening were required. Also, the overall revision rate is very acceptable at a long follow-up. This technique is especially attractive for younger patients facing femoral revisions with extensive bone loss.Cite this article: Bone Joint J 2022;104-B(9):1039-1046.