Trajectories of Work Ability After Total Hip and Knee Arthroplasty: A Latent Class Growth Analysis

Gernert, M., Schuler, M., Dejonghe, L. A. L., & Schaller, A. (2026). Trajectories of Work Ability After Total Hip and Knee Arthroplasty: A Latent Class Growth Analysis. Journal of occupational rehabilitation, 10.1007/s10926-025-10358-4. Advance online publication. https://doi.org/10.1007/s10926-025-10358-4

Abstract: 

Purpose: Total hip arthroplasty (THA) and total knee arthroplasty (TKA) as treatments for osteoarthritis increasingly affect working-age adults. However, little is known about the development of work ability after THA and TKA. This study investigated different trajectory classes of work ability after THA and TKA.

Methods: This prospective study included 146 working patients (THA n = 51, TKA n = 95). They received THA/ TKA treatment as usual, including surgery, rehabilitation, and optional post-rehabilitation programmes. The primary outcome work ability was assessed five times (before surgery, end of rehabilitation, 3-month, 6-month, and 12-month follow-up) with the Work Ability Score. Additionally, the questionnaires included sociodemographic, health-, rehabilitation-, and work-related data. We applied a latent class growth analysis to identify distinct trajectory classes of work ability over 12 months, and examined associated factors using univariable multinominal logistic regression analyses in MPlus.

Results: We found three distinct trajectory classes of work ability within one year after THA/ TKA: no improvement (24.5%), delayed improvement (36.6%), and early improvement in work ability (38.9%). Preoperative predictors for work ability trajectory classes were sex, pain intensity, functional ability in everyday life, and risk of work-related disabilities. Furthermore, work ability trajectory classes were associated with participation in the T-RENA post-rehabilitation programme, and with pain intensity one year after having started rehabilitation.

Conclusion: Despite the fact that most patients showed improvements in work ability after THA and TKA, there is a noteworthy proportion who did not. Further studies are needed to enhance identification of these individuals, and to offer targeted interventions.

Trial registration: The study is registered in the German Clinical Trials Register (DRKS00029630).