Effects of COVID-19 pandemic on hip and knee joint replacement surgery in 2020 as demonstrated by data from the NJR

Derek Pegg, Adrian Sayers, Michael Whitehouse and Timothy Wilton On behalf of NJR (ahead of annual report September 2021)

Derek Pegg is a Consultant Trauma and Orthopaedic Surgeon in Mid Cheshire Hospitals Foundation Trust, Leighton Hospital, Crewe. He is Chair of both NJR Regional Clinical Coordinators Committee and NJR Data Quality Committee.

Adrian Sayers is a Medical Statistician at Musculoskeletal Research Unit, Translational Health Sciences, Bristol Medical School, Southmead Hospital, Bristol. He is the senior statistician for the NJR lot 2 contract for Statistical Analysis, Support and Associated Services.

Michael Whitehouse is a Professor of Trauma and Orthopaedics at Bristol Medical School, University of Bristol and Consultant Trauma and Orthopaedic Surgeon at North Bristol NHS Trust. He is a member of the NJR lot 2 contract for Statistical Analysis, Support and Associated Services.

Timothy Wilton is a Consultant Orthopaedic Surgeon at Department of Orthopaedics, Royal Derby Hospital, Derby, with specialist interests in knee and hip replacement surgery. He is Medical Director of the NJR.

We live history, in the present, while it is only future analysis that can provide a true portrayal of our times.

The COVID-19 pandemic continues to exert a profound influence on the lives of individuals and societies around the world. As anticipated in the early phases of the response to the health crisis, it is having a significant effect on orthopaedic surgeons’ ability to provide joint replacement surgery (JRS) for patients. The National Joint Registry (NJR) provides independent and accurate data on this aspect of healthcare. Such data demonstrates that there has been over a 50% reduction in provision of JRS over the last twelve months. To alleviate this shortfall, if all hospital units were able to return to pre-pandemic levels along with an ambitious 10% increase in activity, we would see a minimum of five years before the ‘backlog’ is fully conquered. These estimates do not account for the ‘natural’ annual increase in the volume of service provision for joint replacements of approximately 5% that has been observed consistently to occur in the NJR data. Current trends suggest this backlog is continuing to increase and there is speculation that ‘catch up’ will take very much longer, even if considerable resources and investment can be provided.

Last year was an unusual time for the provision of joint replacement surgery. By presenting analysis of registry data from 2020, we can clearly demonstrate significant lowering of the volume of activity and get some insight into projected increases needed for recovery. At the time of writing (April 2021) volumes continue to be lower in comparison to pre-pandemic levels. Plans for recovery to previous levels of surgery are starting to be implemented in some hospital units but many other units continue to struggle, and some have barely re-commenced JRS. The ability to catch up with lost activity is a huge challenge everywhere, but we know, even as lockdown is lifted, that we may well face further issues in the months and years ahead, such as repeated waves of COVID-19.

We hope this article will provide the nations’ health economy with objective insight into the effects COVID-19 has had on this type of elective surgery, assist in evaluating the magnitude of the challenge and help us return to pre-pandemic levels of JRS provision. It could also help calculate the time and potential resource required to regain the lost activity which will be crucial for complete recovery.

We reviewed NJR data in total for years 2018 through to March 2021. We looked at hip and knee operations, performed in 2020. This was compared with 2019 activity, preceding the COVID-19 pandemic. We also reviewed the activity data across regions, and for both NHS and independent sector units.

Analysis of the data from Northern Ireland, Wales and England (Scotland has its own registry and does not submit data to the NJR) enables comparison of the effects of the pandemic on the devolved healthcare regions. Further separation of England into regions allows variation due to structural and organisational differences to be highlighted.

In 2020, the NJR recorded 59,343 primary hip and 53,888 knee primary joint replacement procedures (to date*). This represents 57% and 49% of the usual activity of primary procedures compared with 2019, across the whole of the NJR’s geographical footprint. Early data demonstrates this significant loss of activity has continued into 2021 (Figure 1). Thus analysis of the last twelve months (financial year 2020/21) is likely to see significantly greater reduction in overall activity, although the precise figures cannot yet be provided since some data is still being entered for the last few months (historically the ‘missing’ data due to delayed entry are unlikely to provide more than a further 15% for the first three months of 2021).

Across the devolved health economies of Northern Ireland and Wales, we saw a greater reduction in activity compared to England, (Table 1) and hence the recovery period may be longer.

Across the regions in England’s NHS units there was also variation in activity, London having been able to maintain 62% hip and 56% knee activity, while in the East Midlands only 41% of hip and 33% knee JRS was achieved (Table 2).

Absolute numbers for both NHS and Independent providers both fell but as expected, proportionally less so for Independent units (Table 3).

Figure 1 shows how all JRS activity recorded on the NJR fell dramatically at the end of March 2020 (week 13) and then a slow but steady recovery started more than eight weeks later. Recovery then peaked at the end of October, week 40, with a steady decline until mid-December, at week 51. This reflects issues with the prevalence of COVID-19 variants and increase in related hospital admissions during this period. Several geographical regions struggled at different times with community incidents and the demand this placed on secondary care, in general.

Table 1 shows in the case of primary surgery, a greater loss of activity is seen with knee surgery than with hip surgery across the devolved health economies. This is also seen across all regions in England when looking at data for both primary and revision surgery. Total hip replacements performed for management of a fractured neck of femur may account for some of the relative preservation of total hip numbers vs total knees.

Figure 2 demonstrates variation in NHS units across the former Strategic Health Authorities in England for primary and revision surgery combined.

Table 3 illustrates figures across all providers and across both public and independent funding. Knee replacement activity has fallen proportionally more than hip replacement surgery, other than the small number of ISTC cases privately funded.

Clearly COVID-19 has had a severe and detrimental effect on JRS in all geographical areas shown. Although the spring of 2020 had virtually zero activity there has been a steady partial recovery. However, the data demonstrates that this is still far short of pre-pandemic levels of activity. As a result, the backlog of patients awaiting surgery continues to increase.

The burning question is not only when will some units be able to return to their previous orthopaedic productivity levels but also where and when will increased activity allow catch up with the backlog of patients awaiting JRS? Estimates based on this data suggest, with an expected >50% reduction over 2020/21, and an ambitious increased activity for each unit by 10%, it will take over five years for recovery to pre-pandemic levels. However, even before COVID-19 coloured the landscape, demands and waiting times for JRS were increasing. There is no short-term fix and it would be valuable to see recovery as part of a planned medium and long term solution.

As ever with healthcare, cause and resolutions are multi-factorial and therefore it becomes very difficult to give precise calculations and time-to-recovery estimates given the number of variables involved in the delivery of JRS in the context of wider healthcare delivery. The effects and response to COVID-19 potentially change with every mutation COVID-19 throws at mankind. We have fortunately seen early encouraging signs that successful vaccinations will provide some degree of protection for the often elderly and vulnerable who are commonly undergoing major joint replacement surgery. This is an obvious beacon of hope when many of us have witnessed the devastating effects COVID-19 can have on both colleagues and patients. This appears particularly so for patients in the peri-operative and immediate post-operative period following major surgery such as JRS for trauma1. At the time of writing, the full effects of COVID-19 have yet to be realised. We can estimate that the current trends demonstrate that during the financial year 2020/21 we will see well over 50% loss of activity, proportionally greater in NHS units, over this 12-month period. It is our ability to return to above pre-pandemic levels of surgery that will minimise the devastating and disabling effects that joint pathology can have on the individuals and the distress this can cause to immediate family and friends. Orthopaedic patients surveyed during the pandemic reported an increase in their symptoms and associated feelings being ‘worse than death’2. There is also a sense that there will be an increased burden such patients are likely to place on community care services in their aftercare, as well as hospitals; and the very real danger that some will have sub optimal results because of the delay in their surgery.

One of the many unknowns will also be how many patients either succumbed to COVID-19 or other health issues, before they were due to undergo arthroplasty surgery? Or how many patients will have decided to change their decision to have surgery by considering the additional risk of COVID-19 and all that it entails; thus tipping their risk stratification and informed decision towards continued conservative management rather than subject themselves to the risks of surgery at this time. While such decisions might have a small effect of reducing the waiting list for such surgery, this won’t in any way improve the health outcomes for these individual patients, nor will it lessen the overall societal burden of future disability due to arthritis which will still have to be managed by the health service, as well as individual patients and their carers.

Over the last year, there has been an increase in the number of excess deaths as shown by national mortality figures. It is epidemiologists who will only truly be able to ‘judge our present by analysis in the future’. How many delayed cases of JRS will have a sub-optimal outcome as a result of the delay as a consequence of COVID-19? How many cases will have an earlier need for revision surgery? Only the future holds the answer. For now, we know we have a problem that currently has no easy answer, but it seems likely that the longer we continue to accumulate an increased waiting list burden, the worse will be the consequences for our arthritic patients in terms of both delay, and quite possibly quality of outcome.

*The registry is only as good and accurate as the data input, in a timely manner. In 2019 80% of data was uploaded within one month and 90% within three months, therefore small changes in total numbers for the last quarter may still occur, as ongoing data quality audit confirms data accuracy with hospital units.

We continue to be grateful for the continued work of all those responsible for data entry into the NJR, the surgeons and all the patients who consent to their data being held on the NJR, helping drive forward safety, quality and shaping joint replacement surgery for the future.

Data provided by Northgate Public Services - NJR Lot 1 contract for NJR data management, data solutions and associated services.

References

1. COVIDSurg Collaborative. Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS- CoV-2 infection: an international cohort study. Lancet. 2020;396(10243):27-38.

2. Clement ND, Scott CEH, Murray JRD, Howie CR, Deehan DJ, IMPACT-Restart Collaboration. The number of patients “worse than death” while waiting for a hip or knee arthroplasty has nearly doubled during COVID-19 pandemic. Bone Joint J. 2021;103-B(4):672-80.