Inpatient Recovery of Function After Knee Replacement: A Longitudinal Evaluation Across Four Sequential Care Pathway...

Area of Science:

• Orthopedics
• Rehabilitation Medicine
• Health Services Research

Background:

• Inpatient recovery of activities (IRoA) is crucial after total knee replacement (TKR), indicating regained patient independence.
• Preoperative prediction of IRoA aids decision-making but may lose accuracy with evolving healthcare pathways.

Purpose of the Study:

• To assess the stability of IRoA predictors across different TKR care pathway redesigns.
• To evaluate the temporal transportability of IRoA prediction models over time.

Main Methods:

• Retrospective longitudinal cohort study of 1853 TKR patients (2009-2020).
• Analysis across four sequential care pathway periods (Joint-Care, Function Tailored, Fast Track, Prehabilitation).
• IRoA assessed via modified Iowa Levels of Assistance Scale (mILAS); predictors selected using multinomial regression and AIC.

Main Results:

• Predictor stability varied significantly across care pathways; age was consistently important, while others like BMI were not retained.
• Model performance declined when applied to later care pathways, with predicted correct proportions dropping.
• The Prehabilitation model achieved a predicted correct proportion of 0.65 within its own period.

Conclusions:

• Prediction of IRoA after TKR is sensitive to changes in care pathway design.
• Variable predictor relevance and declining model performance limit temporal transportability.
• Continuous model updating and local recalibration are essential for maintaining clinical utility in dynamic healthcare settings.