The aim of this study was to identify the effect of COVID-19 lockdown on the rates, types, mechanisms and mortality of musculoskeletal trauma across Scotland.

Data for all musculoskeletal trauma requiring operative treatment was collected prospectively from five orthopaedic units across Scotland during the initial lockdown period (23/03/2020-28/05/2020). This was compared with data for the same timeframe in 2018 and 2019. Data collected included all cases requiring surgery, injury type, mechanism of injury, and inpatient mortality.

1315 patients received operative treatment in 2020 compared to 1791 in 2019 and 1719 in 2018. The numbers of all injury types decreased, but the relative frequency of hip fractures increased(36.3% 2020 vs 30.2% 2019, p<0.0001 & 30.7% 2018, p<0.0001). Significant increases were seen in proportion of DIY-related injuries(3.1% 2020 vs 1.7% 2019, p=0.01 & 1.6% 2018, p<0.01) and injuries caused by falls(65.6% 2020 vs 62.6% 2019, p=0.08 & 61.9% 2018, p=0.05). Significant decreases were seen in proportion of RTCs(2.6% 2020 vs 5.4% 2019, p<0.0001 & 4.2% 2018, p=0.02) and occupational injuries(1.8% 2020 vs 3.0% 2019, p=0.03 & 2.3% 2018, p=0.01). A significant increase in proportion of self-harm injuries was seen(1.7% 2020 vs 1.1% 2019, p=0.19 & 0.5% 2018, p<0.0001). Mortality of trauma patients was significantly higher in 2020 (4.9%), than in 2019 (3.2%, p=0.02) and 2018 (2.6%, p<0.0001).

In conclusion, lockdown has resulted in a marked reduction of musculoskeletal trauma requiring surgery in Scotland. There have been major changes in types and mechanisms of injury, and mortality of trauma patients has risen significantly.

The rising prevalence of osteoarthritis, associated with an ageing population, is expected to deliver increasing demand across Scotland for primary hip and knee arthroplasty in the future.

Understanding the scale of potential change to operative workflow is essential to ensure adequate provision of services, and prevent prolonged waiting times that can cause patient harm.

We therefore set out to provide projections of future primary hip and knee arthroplasty out to 2038 utilising historical trend data (2008–2018) from the Scottish Arthroplasty Project. All analyses were performed using the Holt's exponential smoothing projection method with the forecast package in R statistics. Results were adjusted for projected future population estimates provided by National Records of Scotland. Independent age & sex group predictions were also performed. All results are presented per 100,000 population at-risk per year (/100k/year).

The predicted rise of primary hip arthroplasty for all ages is from 120/100k/year in 2018 to 152/100k/year in 2038, a 27% increase. The predicted rise of primary knee arthroplasty for all ages is from 164/100k/year in 2018 to 220/100k/year in 2038, a 34% increase. Based on a static 3 day length of stay average this would see 4280 additional patient bed days for hips, and 7392 for knees, required nationally per year by 2038. The associated supplementary cost to the NHS is anticipated to be around £21 million per annum.

Knowledge of increasing resource utilisation and cost associated with predicted future demand for primary hip and knee arthroplasty provides key information for service organisation and delivery.