Elsevier

The Lancet

Volume 392, Issue 10158, 3–9 November 2018, Pages 1672-1682
The Lancet

Series
Knee replacement

https://doi.org/10.1016/S0140-6736(18)32344-4Get rights and content

Summary

Knee replacement surgery is one of the most commonly done and cost-effective musculoskeletal surgical procedures. The numbers of cases done continue to grow worldwide, with substantial variation in utilisation rates across regions and countries. The main indication for surgery remains painful knee osteoarthritis with reduced function and quality of life. The threshold for intervention is not well defined, and is influenced by many factors including patient and surgeon preference. Most patients have a very good clinical outcome after knee replacement, but multiple studies have reported that 20% or more of patients do not. So despite excellent long-term survivorship, more work is required to enhance this procedure and development is rightly focused on increasing the proportion of patients who have successful pain relief after surgery. Changing implant design has historically been a target for improving outcome, but there is greater recognition that improvements can be achieved by better implantation methods, avoiding complications, and improving perioperative care for patients, such as enhanced recovery programmes. New technologies are likely to advance future knee replacement care further, but their introduction must be regulated and monitored with greater rigour to ensure patient safety.

Introduction

Knee replacement surgery has been routinely done for more than 40 years and usage continues to grow worldwide. Its success is based on improving the quality of life for patients with knee arthritis by reducing pain and improving long-term function. However, 20% of patients are dissatisfied with the outcome of surgery, and research and development in the field focuses on this deficiency. This review concentrates on a number of topical areas in knee replacement, starting with the epidemiology of knee replacement and the variability in intervention rates alongside the indications for surgery. The increasingly important role of patient-reported outcomes and analysis of registry data is considered, together with an overview of the health–economic evidence relating to knee replacement. Enhanced recovery programmes are commonplace and have the potential to positively affect patient outcomes. Development of new implants and supportive technologies is continuously led by the industry, but more robust evidence to support their introduction is still required; we therefore review the regulatory requirements for assessment of new devices and strategies to ensure patient safety in this process.

Section snippets

Epidemiology of knee replacement

The use of knee replacement as a treatment for arthritis continues to increase. In the UK, more than 100 000 knee replacements are now done each year and a similar pattern of increased frequency is reported by many worldwide joint registries.1, 2, 3, 4, 5 Total numbers of procedures in the USA have now reached 700 000 per year, and the number is increasing as predicted despite periods of economic downturn (figure 1).6, 7 Projected analyses from different counties all suggest that, even with

Indications for knee replacement surgery

Total knee replacement has traditionally been offered to older patients with intolerable knee pain, unacceptable activity limitation with the loss of highly valued activities, and severe end-stage osteoarthritis of the joint.21 Historically, arthroplasty surgeons have been reluctant to operate on patients with either morbid obesity (because of the higher risk of perioperative complications), and on patients younger than 55 years (because of the increased likelihood of revision in their

Patient-reported outcome after knee replacement surgery

The evaluation of knee replacement has improved over time and the use of patient-reported outcome measures have become more common and influential. A recent systematic review showed 32 different measures that have been used for this purpose, with the Western Ontario and McMaster Universities Osteoarthritis (WOMAC), the Knee Injury and Osteoarthritis Outcome Score, and the Oxford Knee Score (OKS) widely used.34 These instruments have shown that knee replacement improves quality of life for the

Cost-effectiveness of knee replacement surgery

As one of the most commonly done elective procedures in the world, total knee replacement has not surprisingly been the subject of a substantial number of cost-effectiveness analyses. Using the health economists' favoured outcome measure—quality-adjusted life-years (QALYs)—these studies have typically estimated the ratio of incremental costs to health gain from total knee replacement to be between approximately £1000 and £12 000 for the average patient in different health-care systems, which is

Enhanced recovery after knee replacement surgery

Enhanced recovery programmes use a multimodal approach aimed at improving the care and subsequent clinical outcome for patients undergoing knee arthroplasty. First proposed in 1997,54 this approach aims to minimise the physiological and psychological stresses of surgery through the use of specific interventions throughout the care pathway.55 The principal components of enhanced recovery programmes can be broadly thought of in terms of preoperative optimisation of patients' comorbidities,

Patterns of implant use

Analysis of national registry data has become a cornerstone of assessment of knee replacement surgery, reinforced by improvements in data capture, as seen in the UK National Joint Registry (UK NJR).1 Data from all published registries show expanding usage of knee replacement over time, with women most likely to have surgery, and increasing numbers of patients younger than 60 years having surgery.1, 2, 3, 4, 5 Most implantations are cemented total knee replacements, with far fewer partial

Design of total condylar knee replacement

Posterior cruciate retaining or sacrificing total condylar knee designs remain the two most widely used total knee replacement options.1, 2, 3 Incremental design development continues, such as gender-specific and high-flex components, but evidence that these changes in component shape produce any meaningful improvement in outcome is sparse.75 Most knee replacements still use a metal on polyethylene-bearing surface and polyethylene wear remains a major cause of implant failure.1, 2, 4 Around 20

The regulation and evaluation of innovation in knee replacement surgery

The majority of medical devices and surgical implants, including knee replacements, are used without problem or concern, but in some situations problems have arisen. For example, in the use of metal-on-metal hip replacements in which modifications to design resulted in the production of excessive metal wear products, in some patients substantial local and sometimes systemic toxic effects were observed.91 As a result, the regulatory authorities throughout the world have begun to make changes to

Conclusion

Knee replacement surgery is a highly successful established technology, with good evidence of successful treatment outcome and long-term implant survival. A proportion of patients continue to have poor results and addressing this issue is the major challenge for improving care, particularly given the continued increase in worldwide usage and the increasing numbers of younger patients undergoing surgery. Continued incremental changes in implant design do not appear to have achieved any

Search strategy and selection criteria

We searched MEDLINE and PubMed from Jan 1, 1970, to April 30, 2018, using the search term “knee” in combination with “replacement”, “joint”, “total”, “partial”, “arthroplasty”, “epidemiology”, “mortality”, “morbidity”, “outcomes”, “registry”, “enhanced-recovery”, “indications”, “effectiveness”, “cost-effectiveness”, “survivorship”, “follow-up”, “innovation”, “evaluation”, and “regulation”. We concentrated on results from randomised trials, registries, and large population cohort studies. We

References (100)

  • A Escobar et al.

    Patient acceptable symptom state and OMERACT-OARSI set of responder criteria in joint replacement. Identification of cut-off values

    Osteoarthritis Cartilage

    (2012)
  • S Kent et al.

    Hospital costs in relation to body-mass index in 1·1 million women in England: a prospective cohort study

    Lancet Public Health

    (2017)
  • H Kehlet

    Multimodal approach to control postoperative pathophysiology and rehabilitation

    Br J Anaesth

    (1997)
  • RL Johnson et al.

    Neuraxial vs general anaesthesia for total hip and total knee arthroplasty: a systematic review of comparative-effectiveness research

    Br J Anaesth

    (2016)
  • T Chen et al.

    Comparison of the effectiveness and safety of topical versus intravenous tranexamic acid in primary total knee arthroplasty: a meta-analysis of randomized controlled trials

    J Orthop Surg Res

    (2017)
  • P O'Toole et al.

    Projected Increase in periprosthetic joint infections secondary to rise in diabetes and obesity

    J Arthroplasty

    (2016)
  • B Zmistowski et al.

    Diagnosis of periprosthetic joint infection

    J Arthroplasty

    (2014)
  • AD Liddle et al.

    Adverse outcomes after total and unicompartmental knee replacement in 101 330 matched patients: a study of data from the National Joint Registry for England and Wales

    Lancet

    (2014)
  • LP Hunt et al.

    45-day mortality after 467 779 knee replacements for osteoarthritis from the National Joint Registry for England and Wales: an observational study

    Lancet

    (2014)
  • AK Nebergall et al.

    Five-year experience of vitamin E-diffused highly cross-linked polyethylene wear in total hip arthroplasty assessed by radiostereometric analysis

    J Arthroplasty

    (2016)
  • C Rivière et al.

    Alignment options for total knee arthroplasty: a systematic review

    Orthop Traumatol Surg Res

    (2017)
  • V Kulshrestha et al.

    Outcome of unicondylar knee arthroplasty vs total knee arthroplasty for early medial compartment arthritis: a randomized study

    J Arthroplasty

    (2017)
  • AJ Smith et al.

    Failure rates of metal-on-metal hip resurfacings: analysis of data from the National Joint Registry for England and Wales

    Lancet

    (2012)
  • 14th annual report 2017. National Joint Registry for England, Wales, Northern Ireland and the Isle of Man: surgical data to 31 December 2016

  • Hip, knee & shoulder arthroplasty: annual report

  • The New Zealand Joint Registry: eighteen year report January 1999 to December 2016

  • O Robertsson et al.

    Annual report 2016—The Swedish Knee Arthroplasty Register

  • American Joint Registry 2017 annual report

  • SM Kurtz et al.

    Impact of the economic downturn on total joint replacement demand in the United States: updated projections to 2021

    J Bone Joint Surg Am

    (2014)
  • AM Weinstein et al.

    Estimating the burden of total knee replacement in the United States

    J Bone Joint Surg Am

    (2013)
  • H Maradit Kremers et al.

    Prevalence of total hip and knee replacement in the United States

    J Bone Joint Surg Am

    (2015)
  • BL Young et al.

    Trends in joint replacement surgery in patients with rheumatoid arthritis

    J Rheumatol

    (2017)
  • E Losina et al.

    The dramatic increase in total knee replacement utilization rates in the United States cannot be fully explained by growth in population size and the obesity epidemic

    J Bone Joint Surg Am

    (2012)
  • AD Hanchate et al.

    Massachusetts health reform and disparities in joint replacement use: difference in differences study

    BMJ

    (2015)
  • I Falbrede et al.

    Utilization rates of lower extremity prostheses in Germany and Switzerland: a comparison of the years 2005–08

    Orthopade

    (2011)
  • MJ NiemeläInen et al.

    Different incidences of knee arthroplasty in the Nordic countries: a population-based study from the Nordic Arthroplasty Register Association

    Acta Orthop

    (2017)
  • P Dieppe et al.

    Who should have knee joint replacement surgery for osteoarthritis?

    Int J Rheum Dis

    (2011)
  • GMMJ Kerkhoffs et al.

    The influence of obesity on the complication rate and outcome of total knee arthroplasty: a meta-analysis and systematic literature review

    J Bone Joint Surg Am

    (2012)
  • LC Burns et al.

    Pain catastrophizing as a risk factor for chronic pain after total knee arthroplasty: a systematic review

    J Pain Res

    (2015)
  • JE Collins et al.

    Effect of obesity on pain and functional recovery following total knee arthroplasty

    J Bone Joint Surg Am

    (2017)
  • PR Fortin et al.

    Timing of total joint replacement affects clinical outcomes among patients with osteoarthritis of the hip or knee

    Arthritis Rheum

    (2002)
  • PA Manner et al.

    AAOS appropriate use criteria: surgical management of osteoarthritis of the knee

    J Am Acad Orthop Surg

    (2018)
  • Osteoarthritis: care and management. Clinical guideline [CG177]

  • ST Skou et al.

    A randomized, controlled trial of total knee replacement

    N Engl J Med

    (2015)
  • Hip & knee replacement for osteoarthritis top 10

  • Price AJ, Smith J, Dakin HA, et al. Introducing standardized and evidence based thresholds for hip and knee replacement...
  • NJ Giori et al.

    Risk reduction compared with access to care: quantifying the trade-off of enforcing a body mass index eligibility criterion for joint replacement

    J Bone Joint Surg Am

    (2018)
  • K Harris et al.

    Systematic review of measurement properties of patient-reported outcome measures used in patients undergoing hip and knee arthroplasty

    Patient Relat Outcome Meas

    (2016)
  • DW Murray et al.

    A randomised controlled trial of the clinical effectiveness and cost-effectiveness of different knee prostheses: the Knee Arthroplasty Trial (KAT)

    Health Technol Assess

    (2014)
  • H Dakin et al.

    Rationing of total knee replacement: a cost-effectiveness analysis on a large trial data set

    BMJ Open

    (2012)
  • Cited by (458)

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