A high physical activity level after total knee arthroplasty does not increase the risk of revision surgery during the first twelve years: A systematic review with meta-analysis and GRADE.

BACKGROUND: High physical activity (HPA) levels after total knee arthroplasty (TKA) might be related to increased wear and subsequent aseptic loosening, negatively affecting TKA survival. This systematic review studied the association between activity levels and risk of revision surgery at medium (3-10 years) and long term (>10 years) follow up in patients with TKA. METHODS: Databases (PubMed, Embase) were searched up to 12 October 2021. Studies comparing low physical activity (LPA) and HPA levels in TKA patients and related risk of revision surgery were eligible for inclusion. After data extraction and evaluation of methodological quality, a meta-analysis was performed. Quality of evidence was assessed using the GRADE framework. PROSPERO registration: CRD42020194284. RESULTS: Five cohort studies and one case-control study met the inclusion criteria, involving 4811 TKA procedures in 4263 patients (mean follow up 4-12 years). Five studies were of moderate methodological quality and one of low quality. Meta-analysis demonstrated no association between HPA level and an increased risk of all-cause revision surgery (risk ratio (RR) 0.62, 95 % confidence interval (CI) 0.24-1.63, level of certainty: very low) or revision surgery due to aseptic loosening (RR 1.33, 95 % CI 0.34-5.24, level of certainty: moderate). Only one study reported on survivorship, with an improved survivorship for the HPA group (odds ratio of 2.4, 95 % CI 1.2-4.7, level of certainty: low). CONCLUSION: During the first 12 postoperative years after TKA, there seems to be no increased risk for revision surgery for patients with a HPA level compared with patients with an LPA level.

Correction to: No difference in mid-term survival and clinical outcome between patient-specific and conventional instrumented total knee arthroplasty: a randomized controlled trial.

In the original article, one of the co-author's (W. van der Weegen) middle name has been missed in the publication of the article. The correct complete name should be W. van der Weegen.

No difference in mid-term survival and clinical outcome between patient-specific and conventional instrumented total knee arthroplasty: a randomized controlled trial.

PURPOSE: The purpose of this multicentre prospective randomized controlled trial was to compare the survival rate and clinical outcome in total knee arthroplasty (TKA) after MRI-based patient-specific instruments (PSI) and conventional instruments 5 years after initial surgery. METHODS: At a mean follow-up of 5.1 years (0.4), 163 patients (90.6%) with a mean age of 71.8 years (8.7) were analysed. A survival analysis with revision of the TKA as endpoint was performed. The Knee Society Score (KSS), evaluations on plain radiographs and patient-reported outcome measures (PROMs) were obtained preoperatively and at each FU. RESULTS: At final follow-up, one TKA in the PSI- (1.2%) and 3 TKAs in the conventional group (3.8%) had undergone revision surgery (n.s.). No radiological abnormalities were noted at any time point. Postoperatively, the KSS and PROMs significantly improved within each group compared with the preoperative values. There were no clinically relevant differences for the KSS [PSI: 77.4, 9.8 (95% CI 75.0-79.7) vs. conventional: 77.3 10.5 (95% CI 74.9-79.8)] and the PROMs between both groups (n.s.) at 5 years follow-up. CONCLUSION: There is still a lack of reliable data on the survival of TKA and clinical evidence, when using PSI for TKA. Longer follow-up studies are, therefore, needed. LEVEL OF EVIDENCE: I.

Intra-operative results and radiological outcome of conventional and patient-specific surgery in total knee arthroplasty: a multicentre, randomised controlled trial.

PURPOSE: This prospective, double-blind, randomised controlled trial was designed to address the following research questions: firstly, is there a significant difference in outliers in alignment in the frontal and sagittal plane between PSG TKA and conventional TKA. Secondly, is there a significant difference in operation time, blood loss and length of hospital stay between the two techniques. We hypothesise that there will be fewer outliers with PSG TKA and that operation time, blood loss and length of hospital stay can be significantly reduced with PSG. METHODS: A total of 180 patients were randomised for PSG TKA (group 1) or conventional TKA (group 2) in two centres. Patients were stratified per hospital. Alignment of the mechanical axis of the leg and flexion/extension and varus/valgus of the individual prosthesis components were measured on digital, standing, long-leg and standard lateral radiographs by two independent outcome assessors in both centres. Percentages of outliers (>3°) were determined. We compared blood loss, operation time and length of hospital stay. RESULTS: There was no statistically significant difference in mean mechanical axis or outliers in mechanical axis between groups. No statistically significant difference was found for the alignment of the individual components in the frontal plane nor for the percentages of outliers. There was a statistically significant difference in outliers for the femoral component in the sagittal plane, with a higher percentage of outliers in the group 1 (p = 0.017). No such significant result was found for the tibial component in that plane. All interclass correlation coefficients were good. Blood loss was 100 mL less in group 1 (p < 0.001). Operation time was 5 min shorter in group 1 (p < 0.001). Length of hospital stay was identical with a mean of 3.6 days (p = 0.657). CONCLUSIONS: The results in terms of obtaining a neutral mechanical axis and a correct position of the prosthesis components did not differ between groups. A small reduction in operation time and blood loss was found with the PSG system. Future research should especially focus on cost-effectiveness analysis and functional outcome of PSG TKA. LEVEL OF EVIDENCE: I.

Clinical efficacy of postoperative autologous transfusion of filtered shed blood in hip and knee arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) or total hip arthroplasty (THA) regularly results in postoperative requirement of blood transfusion. Because of the disadvantages of allogeneic blood transfusion (ABT) such as the risk of transfusion-associated infections, incompatibility-related transfusion fatalities, or immunomodulatory effects, a continuing effort to reduce allogeneic blood transfusion is important. For this purpose, the effect of reinfusion of drain blood, via a postoperative wound drainage and reinfusion system, on the need for allogeneic blood transfusion was evaluated. STUDY DESIGN AND METHODS: Using a prospective observational quality assessment design, we compared 135 patients scheduled for TKA or THA with a historic group of 96 patients. In the study group the Bellovac ABT autotransfusion system was used. The shed blood was returned either when 500 mL were collected or at most 6 hours after surgery. Compared were the preoperative, postoperative, and discharge hemoglobin, as well as the number of allogeneic blood transfusions. RESULTS: There were no statistical differences between preoperative, postoperative, and discharge hemoglobin levels. Autologous transfusion reduced the number of patients receiving ABT overall from 35 percent (control) to 22 percent (study). The decrease of allogeneic transfusion requirement was most significant after TKA: from 18 percent to 6 percent (p < 0.001). CONCLUSION: We conclude that the Bellovac ABT device reduces allogeneic blood transfusions in TKA and THA.