Patient Safety in Major Joint Replacement Surgery

The demand for hip and knee replacement in the UK is rising steadily despite efforts towards improving non-arthroplasty interventions. The National Joint Registry recorded roughly a quarter of a million hip and knee replacements in 2024 with an anticipated 40% increase by 2060 driven by population aging and an increased incidence of osteoarthritis related to longer life expectancy and obesity.

More younger patients are undergoing surgery in absolute numbers as surgeons gain confidence in the results with both new and established implants. This group of patients has often suffered previous sports injury and expect a continuing high level of activity.

In terms of survival of the implant without revision, 94% of hip replacements last over 20 years and 82% of knees over 25 years. In terms of function, the patient reported outcomes are generally excellent.

Despite this background, there are issues. It has been stated that as many as 20% of patients with knee replacements remain dissatisfied. In the best performing centres, the deep infection rate is well below 1%, but the impact of this is catastrophic and is associated with a 15-25% all cause mortality within 5 years.

Consequently, there is every reason to ensure patient safety in this large and often vulnerable population. Even at a basic level, it is sobering that the April 2025-March 2026 Never Event figures from NHS England show that the wrong hip implant was inserted in 4 patients and the wrong knee in 14.

There is a broad spectrum of strategies in place to mitigate risk and enhance safe delivery.

Patient and procedure selection – For most patients, the decision-making process is straightforward. However, for those with significant co-morbidities or more complex issues such as previous surgery, more extreme deformity or instability then peer discussion at a formally constituted multi-disciplinary team meeting is strongly advised.

Pre-operative optimisation – Management of obesity and ensuring best control of diabetes and other morbidities along with advice on maximising general physical fitness before surgery reduces the risk of significant complications.

Established pathway of care – Adherence to a standardised pathway such as that published by GIRFT plays a major role in delivering safe and effective care. Common shared protocols for antibiotic prophylaxis and prevention of VTE reduce the risk of error.

Theatre discipline – Strict adherence to aseptic technique along with keeping the number of personnel in theatre and their transits to a minimum is known to reduce the risk of infection.

Checklists – The use of checklists is now standardised across all surgical disciplines. However, instances of wrong site surgery, retained objects and mis-matched implants continue to be reported. Innovations such as bar-code checks of prostheses before final insertion are now used in many centres.

Enhanced recovery protocols – Post-operative analgesia regimes, rapid mobilisation and early discharge from hospital is both safe and reduces the risk of complications with increased patient satisfaction.

Registry data – In UK practice, submission is essentially mandated. Although analysis of outcomes is limited to re-operation or revision, data analysis demonstrates trends in underperformance of implants and any outliers at unit or individual surgeon level.

Enhanced implant surveillance – Beyond Compliance is a UK initiative involving the registration of new or modified implants to identify any problems as quickly as possible. It complements the work of the Orthopaedic Data Evaluation Panel (ODEP) which rates the strength of an implants established evidence of safety and performance.

Surgeon experience – Annual case volume is associated with better outcomes after knee and hip replacements. For primary knee replacement, lower volume surgeons and units have higher rates of complications, readmissions and revisions. For more technically demanding operations such as partial knee replacement the difference is more marked with a 5 year revision rate of 7.2% for low volume surgeons against 4.3% for high volume.

Introduction of robot assisted surgery – Mal-alignment of the implants, leg length discrepancy and abnormal soft tissue tension are all associated with poor results in terms of patient satisfaction and early failure in both hip and knee replacement surgery. It has been hoped that the precision of using robot assistance will improve outcomes. There is some evidence that in addition there is less blood loss, less soft tissue damage and lower analgesia requirements. However, a recent high quality prospective study (RACER-Knee) shows that robot assisted total knee replacement did not provide a clinically meaningful patient benefit at 12 months after randomisation and was more costly and had similar safety profiles.

Dual consultant operating – Across all surgical specialties, models of dual consultant operating (DCO)have been demonstrated to improve patient safety and outcomes. Recent guidance published by the RCSEd proposes that in the right circumstances DCO will aid learning new techniques, support less experienced surgeons, reduce fatigue, burnout and cognitive overload and supports surgeon confidence and resilience. In addition, it helps to build professional networks. For complex primary and revision joint replacement surgery, DCO is supported and encouraged, with a specific note to be made in the National Joint Registry data submission forms if surgery has been done in this way.

In conclusion, there are many layers to ensuring safe surgery in major joint replacement. It is not just down to an individual surgeon and their choice of implant but depends on teams and systems working together. These broader aspects of safe surgery will be explored in depth at the forthcoming Surgical Safey Summit at the RCSEd in April 2027.