Risk of venous thromboembolism after knee, hip, or shoulder arthroplasty

Aims: Arthroplasty is a widely used surgery for end-stage arthritis, but venous thromboembolism (VTE) remains a major postoperative complication. Most previous studies have relied solely on hospital data; no study has examined the effect of national clinical guidelines on the rates of VTE in the UK. This study aimed to assess VTE trends after arthroplasty using linked primary and secondary care data, and the impact of the National Institute for Health and Care Excellence (NICE) guidelines in the UK on VTE rates after arthroplasty. Methods: We used the Clinical Practice Research Datalink (CPRD) Aurum version, the largest primary care database in the UK, and linked hospital and death data for patients undergoing knee, hip, or shoulder arthroplasty between October 2007 and September 2019. The outcome was VTE event within six months of surgery. Trends in VTE were assessed using the Cox-Stuart trend test, and the impact of seasonality and clinical guidelines introduced in 2010, 2012, and 2018 via logistic regression with a polynomial function. Results: A total of 476,620 arthroplasty records were included. The overall VTE incidence was 1.5% (knee (1.6%), hip (1.4%), and shoulder arthroplasty (1%)). More than 30% of the VTEs were found through the linked data. A decline in VTE rates was observed over time for hip (p = 0.004) and knee arthroplasty (p = 0.001). Introduction of NICE guidelines did not significantly change the VTE rate in knee and hip arthroplasty. In shoulder arthroplasty, VTE decreased by 9% after the introduction of the 2018 guidelines. Seasonal variation in the VTE risk differed by joint. Conclusion: Future research should investigate the factors driving the seasonal association in VTE rates, and determine why shoulder arthroplasty showed a unique response after 2018.