ABSTRACT
Aims: This prospective study reports longitudinal, within-patient, patient-reported outcome measures (PROMs) over a 15-year period following cemented single radius total knee arthroplasty (TKA). Secondary aims included reporting PROMs trajectory, 15-year implant survival, and patient attrition from follow-up. Methods: From 2006 to 2007, 462 consecutive cemented cruciate-retaining Triathlon TKAs were implanted in 426 patients (mean age 69 years (21 to 89); 290 (62.7%) female). PROMs (12-item Short Form Survey (SF-12), Oxford Knee Score (OKS), and satisfaction) were assessed preoperatively and at one, five, ten, and 15 years. Kaplan-Meier survival and univariate analysis were performed. Results: At 15 years, 28 patients were lost to follow-up (6.1%) and 221 patients (51.9%) had died, with the mean age of the remaining cohort reducing by four years. PROMs response rates among surviving patients were: one-year 63%; five-year 72%; ten-year 94%; and 15-year 59%. OKS and SF-12 scores changed significantly over 15 years (p < 0.001). The mean improvement in OKS was 18.8 (95% confidence (CI) 16.7 to 19.0) at one year. OKS peaked at five years (median 43 years) declining thereafter (p < 0.001), though at 15 years it remained 17.5 better than preoperatively. Age and sex did not alter this trajectory. A quarter of patients experienced a clinically significant decline (≥ 7) in OKS from five to ten years and from ten to 15 years. The SF-12 physical component score displayed a similar trajectory, peaking at one year (p < 0.001). Patient satisfaction was 88% at one, five, and ten years, and 94% at 15 years. In all, 15-year Kaplan-Meier survival was 97.6% (95% CI 96.0% to 99.2%) for any revision, and 98.9% (95% CI 97.9% to 99.9%) for aseptic revision. Conclusion: Improvements in PROMs were significant and maintained following single radius TKA, with OKS peaking at five years, and generic physical health peaking at one year. Patient satisfaction remained high at 15 years, at which point 2.4% had been revised.
ABSTRACT
AIMS: The primary aim was to assess the incidence of venous thromboembolism (VTE) following total hip replacements (THR) in a low-risk patient group when using 150 mg aspirin as the pharmacological component of VTE prophylaxis on discharge. The secondary aim was to identify factors associated with an increased risk of a VTE event in this low-risk group. PATIENTS AND METHODS: Retrospective review of a consecutive cohort of patients undergoing THR during a 63-month period. Patient demographics, socio-economic status, ASA grade, type of anaesthetic, length of surgery and BMI were recorded. A diagnosis of VTE was assigned to symptomatic patients with positive imaging for a deep vein thrombosis (DVT) and/or a pulmonary embolism (PE) within 8 weeks of surgery. Multivariate logistic regression modeling was used to identify factors associated with VTE after THR. RESULTS: 3880 patients underwent THR during the study period, of which 2740 (71%) were low risk and prescribed aspirin for VTE prophylaxis. There were 34 VTE events, of which 15 were DVTs and 18 were PEs, with 1 patient diagnosed with both. The incidence of VTE was 1.2%, with no VTE-related deaths. Patients incurring a VTE postoperatively were more likely to be male (odds ratio [OR] 2.06, p = 0.022), of older age (OR 0.43, p = 0.047) and were more likely to be socially deprived (OR 0.32, p = 0.006). There was no significant difference with patients given low-molecular-weight heparin (LMWH) as an inpatient prior to discharge on aspirin (p = 0.806), nor any difference with the type of anaesthetic used during surgery (p = 0.719). CONCLUSIONS: Aspirin is a relatively safe and effective choice for VTE prophylaxis in low-risk patients undergoing THR. Male sex and age >70 years were twice as likely to sustain a VTE and patients from the most deprived socio-economic background are 3 times as likely.
