Multimodal Prehabilitation of Frail Patients 70 Years and Older Undergoing Elective Knee or Hip Replacement: A Pilot Randomized Controlled Trial

Background: Frailty is a geriatric syndrome of reduced physiologic reserve that increases surgical risk and is common among older adults undergoing hip or knee replacement. While prehabilitation has shown promise in enhancing outcomes, evidence from randomized controlled trials (RCTs) in frail orthopedic patients is limited. Objective: This study aims to evaluate the feasibility and preliminary data on the effectiveness of a multimodal prehabilitation program for frail patients undergoing elective hip or knee arthroplasty. Methods: A pilot RCT will be conducted at Landspítali-University Hospital. Patients ≥70 years scheduled for surgery with ≥2 months waiting time will be screened for frailty using PRISMA-7, the Clock Drawing Test, and Timed Up \& Go. Patients screening positive for any of the three screening tools will be randomized to multimodal prehabilitation or standard of care. The intervention includes comprehensive geriatric assessment, medication review, tailored physiotherapy using the Otago Exercise Programme, and nutritional counseling if at risk of malnutrition. We will conduct an external pilot for feasibility measures (overall enrollment, recruitment, retention, adherence). Secondary outcomes include physical performance, postoperative complications, patient-reported health status (WOMAC scale) and quality of life (EQ-5D-5L ), length of primary hospital stay, discharge location, falls postoperatively, 180-day readmission and 180-day mortality. Significance: This trial may aid in the design of larger RCT study and provide a signal of the role of multimodal prehabilitation on outcomes, including quality of life and health status among frail arthroplasty patients.