Feasibility of a randomized trial comparing exercise-based rehabilitation to no exercise-based rehabilitation after total knee arthroplasty: DRAW-TKA hybrid 1 RCT.

OBJECTIVE

Trials comparing the effectiveness of exercise-based rehabilitation against no exercise-based rehabilitation are needed, but their feasibility is unclear. The DRAW-TKA feasibility trial aimed to assess recruitment-, retention-, harms-, and procedural feasibility to inform a full-scale effectiveness trial.

DESIGN

This pragmatic, multicentre, parallel, two-arm feasibility trial included participants scheduled for total knee arthroplasty due to osteoarthritis, aged ≥18, who could read and write Danish. Participants were recruited pre-operatively from two hospitals. At discharge, participants were encouraged to be physically active and randomised (one-to-one) to "Referral to exercise" (usual care) or "No exercise". Recruiters, outcome assessors, and intervention-deliverers were masked to allocation. The primary feasibility criteria were based on recruitment rate, retention, participation barriers, and data completeness. Secondary criteria on harms, procedural feasibility, and intervention acceptance.

RESULTS

Between Aug 22nd, 2023, and Feb 29th, 2024, all 445 patients planned for TKA were screened, of whom 338 (76 ​%) were ineligible, 49 of 107 eligible (45·8 ​%) declined participation (wanted exercise), and 25 of 107 (23·4 ​%) were randomly assigned exercise (n ​= ​12) or no exercise (n ​= ​13). Because of intervention-specific withdrawals (n ​= ​3) and attrition, 18 of 25 completed all three-month assessments. Three of four predefined, primary feasibility criteria were met. Clinicians and participants found the trial procedurally feasible and acceptable. No interventional harms occurred.

CONCLUSION

The trial's scientific rationale - allocation to exercise, or no exercise - introduced significant risk of selection and attrition bias in this clinical context, severely limiting the generalisability. Although recruitment was predominantly feasible, further adaptations are required to warrant full-scale initiation.NCT05935020.