Executive summary (across all report areas)

Executive summary

Mr Martyn Porter, NJR Medical Director and Chairman, Editorial Board 

On 31 March 2018, the NJR celebrated 15 years of collecting data when 2,520,000 procedures had been registered. Quite an achievement!

Main headlines and achievements for 2017/18

Data quality has been a major focus for the NJR over the last three years and continues to be so. Only by providing and analysing high quality data that is complete and accurate will the NJR maintain credibility with its various stakeholders.

The data quality audit has now expanded to include the independent sector. Compliance with the audit has been excellent and plans are underway to incorporate a significant amount of automation in to this process to reduce the burden on the hospitals.

The audit itself identifies cases that have not been registered with the NJR but were recorded on hospital systems, further improving compliance with the NJR. Precise calculations of compliance are complex but at the conclusion of the 14/15 audit, approximately 95% of all primary hip and knee operations had been registered and 90% of all revisions.

Within the year, the NJR has worked hard to develop its Accountability and Transparency Model. Twice a year, the NJR carries out a structured analysis of revision and post-operative mortality to identify unexpected variations of both individual surgeons and hospitals. The NJR is now working with the BOA, CQC and NHS Improvement to ensure that the appropriate governance actions are carried out in a timely way. The NJR’s symposium at the 2018 BOA Congress entitled “How to use NJR data responsibly to improve care”, includes the use of data to potentially improve outcomes as well as identifying causes for concern.

This is further supported by enhancements to the consultant level report available from the clinician feedback portal. By providing more detail and early warnings to surgeons regarding potential adverse performance, hopefully any issues can be addressed before they become problematic. The ethos of the registry is to enable surgeons to practice safely rather than to alert them to matters that may be at variance with expected outcomes.

The minimum dataset has also been updated this year. One of the changes will now allow for the registration of Debridement and Implant Retention (DAIR) procedures used in treating infected joint replacements in the early periods following surgery as a separate procedure type, distinct from single stage revision under which they were previously recorded.. To counter the argument that this may encourage surgeons not to carry out exchange of the modular components, simple debridement and washout will also be recorded. These changes will allow more accurate and detailed assessment of these procedures in relation to later revision surgery that may be required for deep infection.

The NJR component database is in the process of being redesigned to allow for more detailed analysis of the types of components that are implanted. This should lead to a better understanding of how the attributes of devices may affect their performance.

The NJR continues to work closely and has strengthened its relationships with GIRFT, ODEP and Beyond Compliance. The NJR also collaborates with other international joint replacement registries and is part of ISAR - the International Society for Arthroplasty Registers. The 2018 symposium was held in Reykjavik, Iceland in May 2018. The NJR was also represented at the EFORT meeting (European Federation of Orthopaedics and Traumatology) in Barcelona in June 2018. The focus of this international work has been on collaboration, sharing registry research findings, developing new methodologies, discussing the utility of PROMs (Patient Reported Outcome Measures), early signal detection and benchmarking of devices.

Main headlines for 2017: Outcomes

The data builds on last year’s findings and the main message of the report is that revision estimates following joint replacement surgery remain low.

The data is structured to show the effect of patient and implant factors on revision estimates. For example, patient factors include gender and age at time of surgery, while implant factors include type of fixation, brand, bearing and head size. The debate has moved on from a comparison of fixation method to one of comparison of joint replacement ‘constructs’. In a hip replacement, for example, a construct would include a description of the brand of socket, femoral stem and bearing material. It is the ‘whole replacement’ that is important to the patient rather than the individual components or method of fixation.

Some hip constructs have revision estimates as low as 2% at 14 years and some knee brands have revision estimates as low as 3% at 14 years. These results are quite remarkable in terms of outcomes for patients and value for the taxpayer.

Although there is variation in revision estimates for implants, the patient continues to be a major factor in outcomes. In particular, it is the young patient who has a much higher revision risk compared to more elderly patients. For example, for hip replacement in male patients under the age of 55 years at the time of surgery, overall, the revision estimate is nearly 16% at 14 years compared to just 2.5% in male patients over 75 years. A similar pattern is evident in knee replacement with revision estimates of nearly 15% at 14 years in female patients less than 55 years at the time of surgery, compared to just 2.5% in female patients over 75 years.

This does not mean that young patients should be denied joint replacement surgery just because they are young and have a high risk of revision, but it does mean that both surgeons and patients should be aware of these facts in order to facilitate ‘shared decision-making’. In this regard the development of an NJR ‘risk calculator’ by Mark Wilkinson and his research team in Sheffield may prove to be timely. Risk calculators are not a new concept but the NJR model is nearing the end of its development and should be available for clinical testing early in 2019. The aim is to be able to enter individual patient information such as age, gender, BMI etc. and for the tool to predict the likelihood for revision, mortality or patient reported outcome measures (PROMs) in a ‘patient like them’. The science and methodology behind this is complex and the current indications are that the predictive power is at the best modest but certainly an improvement on the current general advice on risk given to patients. It is envisaged that these tools will be used in the outpatient setting by the surgeon and patient to facilitate ‘shared decision-making’.

In relation to knee replacement surgery, revision rates are higher for partial knee replacement, compared to total knee replacement. However, other data demonstrates that partial replacements have lower mortality rates and fewer complications than total knee replacement. The effect of surgeon volume is also important. The NJR’s role is not to discourage partial knee replacement surgery, but it would be advisable to consider the implications of these other factors and perhaps limit surgical activity to surgeons who have sufficient volume and can achieve low revision rates.

Much work has been carried out on the classification of components used in shoulder replacement surgery. This is not a straightforward matter as the plethora of implants available and the modes in which they combine are complex. The section on shoulder replacement is very impressive thanks to this classification work. Revision estimates for all elective shoulder replacements in male patients over 75 years are approximately double those for female patients in the same age group.

There are over 700 ankle replacement procedures carried out per year and revision estimates are just under 9% at seven years for all cases, but as for hips and knees, there is considerable variation according to the gender and age of the patient.

Concluding acknowledgements

As mentioned earlier there is considerable additional information available online and I would encourage you to explore the NJR’s dedicated annual report website at www.njrreports.org.uk. The website offers a helpful interactive platform for Part Two of the report, which is the descriptive NJR data; supporting appendices; and, when published, the latest NJR Patient and Public Guides to the annual report.

The NJR continues to work with many stakeholders; the most important, of course, are the patients whom I would like thank for allowing the NJR to use their data.

Many thanks also to the following without which the NJR could not function:
All members of the NJR Steering Committee Members of the NJR sub-committees:
Data Quality Editorial Board Executive
Implant Performance Implant Scrutiny Medical Advisory
Regional Clinical Coordinators Research
Surgical Performance
Members of Data Access Review Group Members of the NJR Patient Network
Other organisations: MHRA
NHS England NHS Improvement
British Orthopaedic Association BHS
Northgate Public Services (UK) Ltd University of Bristol
University of Oxford

On a personal note I would particularly like to thank Laurel Powers-Freeling, Chairman of the NJR and Elaine Young, NJR Director of Operations.
Northgate Public Services and University of Bristol teams have, yet again, done an exceptional job.

Finally, having served on the NJR Steering Committee for over 15 years I will be standing down from the NJR later this year. I have very much enjoyed and learnt from the experience. 

Thank you,

Martyn Porter