Total and partial knee arthroplasty versus non-surgical interventions of the knee for moderate to severe osteoarthritis

Total and partial knee arthroplasty (TKA, PKA) are common treatments for moderate to severe knee osteoarthritis. While effective in symptom management, these surgeries carry potential risks, necessitating careful evaluation of benefits and harms. High-quality evidence comparing TKA/PKA to placebo, sham, or non-surgical interventions is essential to support informed decision-making.

To assess the benefits and harms of TKA and PKA for people with moderate to severe knee osteoarthritis compared to placebo, sham (efficacy), or non-surgical interventions for the knee (effectiveness).

We searched CENTRAL, MEDLINE, Embase, and two trial registers from 2010 to January 2025. We also performed reference and citation checks. Two reviewers independently screened studies, extracted data, and assessed risk of bias and the certainty of evidence.

We included randomised controlled trials of adults with moderate to severe osteoarthritis receiving TKA/PKA compared to placebo, sham, or non-surgical treatments including physiotherapy, weight loss, pharmacotherapy, braces, insoles, and any intraarticular injection. We excluded studies including participants with other joint conditions or having TKA/PKA because of trauma (e.g. fracture), infection, or revision.

We reported on pain, physical function, knee surgery, patient satisfaction with treatment outcomes, health-related quality of life, serious adverse events, and withdrawals due to adverse events. We measured outcomes at short-term (≤ 6 months), intermediate-term (6 to 12 months), and long-term (≥ 1 year) follow-up.

We used the Cochrane RoB 1 tool to assess risk of bias.

We conducted a narrative synthesis, reported on risk ratios (RRs) for dichotomous data and mean differences (MDs) for continuous data with a 95% confidence interval (CI), and used GRADE to assess the certainty of evidence.

One randomised controlled trial conducted in Denmark met the inclusion criteria. The study enrolled 100 adults with primary mild to severe knee osteoarthritis (Kellgren-Lawrence score ≥ 2 to 4) and compared TKA followed by a non-surgical programme (exercise, osteoarthritis education, dietary advice, insoles, pain medication) to the same non-surgical programme alone.

Pain Compared to a non-surgical programme, unilateral TKA may reduce pain at a level that is clinically important at one year (MD 17.60, 95% CI 8.25 to 26.95; 1 study, 100 participants; low-certainty evidence). The certainty of evidence was low given the imprecision of results and risk of bias. Physical function Compared to a non-surgical programme, unilateral TKA may improve physical function at one year, but the improvement might not be clinically important (MD 12.40, 95% CI 3.06 to 21.74; 1 study, 100 participants; low-certainty evidence). The certainty of evidence was low given the imprecision of results and risk of bias. Knee surgery Compared to a non-surgical programme, unilateral TKA may reduce the need for a follow-up knee surgery (revision or subsequent knee surgery and initial knee surgery) at one year (RR 0.04, 95% CI 0.00 to 0.62; 1 study, 99 participants; low-certainty evidence). The certainty of evidence was low given the imprecision of results and risk of bias. Patient satisfaction with treatment outcomes The included trial did not assess patient satisfaction with treatment outcomes. Health-related quality of life There is probably no clinically important difference in health-related quality of life between unilateral TKA and non-surgical treatment at one year (MD 0.09, 95% CI 0.01 to 0.18; 1 study, 100 participants; moderate-certainty evidence). The certainty of evidence was moderate due to risk of bias and was not downgraded for imprecision because the effect estimates and the CI did not cross the minimal clinically important difference line. Serious adverse events Compared to a non-surgical programme, unilateral TKA may increase serious adverse events, but the evidence is very uncertain (RR 4.00, 95% CI 1.79 to 8.94; 1 study, 100 participants; very low-certainty evidence). The certainty of evidence was very low given the imprecision of results, indirectness, and risk of bias. Withdrawals due to adverse events There may be no difference in withdrawals due to adverse events between unilateral TKA and non-surgical treatment, but the evidence is very uncertain (n = 0 in both groups, Not estimable; 1 study, 100 participants; very low-certainty evidence). The certainty of evidence was very low given the imprecision of results.

Compared to a non-surgical programme alone, TKA followed by a non-surgical programme may reduce pain at a level that is clinically important; may improve physical function at a level that is not clinically important; and may reduce the need for follow-up knee surgery. There is probably no clinically important difference in health-related quality of life between TKA followed by a non-surgical programme and a non-surgical programme alone. TKA followed by a non-surgical programme may increase the risk of serious adverse events, but the evidence is very uncertain. There may be no difference between groups in withdrawals due to adverse events, but the evidence is very uncertain. The conclusions of this study should be interpreted with caution due to several limitations: the evidence is based on a single study conducted in Denmark; TKA eligibility criteria used by surgeons were not clearly reported; 12% of adults had mild osteoarthritis; adults who reported severe pain in the previous week were excluded; and the included study employed a broad definition of serious adverse events. These factors may affect the reliability and generalisability of the findings.

LPB was supported by the Arthritis Society PhD Award (#21-0000000085), matched funding from the University of Ottawa and co-supervisors' research funds, the Ontario Graduate Scholarship, and the University of Ottawa Admission Scholarship. In the past five years, LPB also received support from the Hans K. Uhthoff MD FRCSC Graduate Fellowship (#712240301930), the Queen Elizabeth II Graduate Scholarships in Science and Technology, the University of Ottawa Excellence Scholarship, the Eastern District of the Ontario Physiotherapy Association (#712140302327, #712200305332), and l'Ordre Professionnel de la Physiothérapie du Québec.

Protocol (2023) 10.1002/14651858.CD015378.