2026/06/22 by Julius Sala, J Sirola, Antti Jaroma +2 · 1 voice
Medicine · #Total Knee Arthroplasty Outcomes #Orthopaedic implants and arthroplasty #Anesthesia and Pain Management
paper · doi:10.2340/17453674.2026.46072
openalex publication_date 2026/06/22 · openalex created_date 2026/06/23 · openalex updated_date 2026/07/27
BACKGROUND AND PURPOSE: Stiffness after total knee arthroplasty (TKA) is a common early complication and multiple risk factors are recognized. We aimed to investigate the risk factors for manipulation under anesthesia after primary TKA and for the subsequent revision TKA in patients requiring manipulation using national healthcare registers. METHODS: We used the comprehensive register data of the PERFECT project that included data from the Finnish arthroplasty register (FAR) and the Care Register of Health Care (CRHC). We excluded patients under 40 years old. The Aalen-Johansen estimator and Cox proportional hazards regression model were used in the risk assessment. RESULTS: 154,883 patients had primary TKA in Finland in 1999-2020 , of which 3,861 patients required manipulation within 1 year of primary TKA. The 1-year cumulative incidence of manipulation was 2.5%. In the multivariable analysis, female sex (hazard ratio [HR] 1.53, CI 1.42-1.64), diabetes mellitus (HR 1.19, CI 1.08-1.31), coronary artery disease (HR 1.25, CI 1.12-1.39), and hypercholesterolemia (HR 1.16, CI 1.06-1.28) were associated with an increased risk of manipulation. Increasing age was associated with a decreased risk of manipulation (multivariable HR 0.94 per year, CI 0.94-0.94). Patients requiring manipulation within 1 year of primary TKA had a significantly increased risk of revision TKA (HR 2.26, CI 2.05-2.50). The 10-year cumulative risk of revision TKA after manipulation was 15% (CI 14-16). CONCLUSION: Manipulation was more likely to be performed for females, relatively younger patients, and patients with diabetes mellitus, coronary artery disease, or hypercholesterolemia. Patients who had manipulation within 1 year of primary TKA had an increased risk of revision with a 10-year cumulative risk of revision of 15%.