A RANDOMISED CONTROLLED TRIAL COMPARING ACCELERATED DISCHARGE WITH STANDARD CARE AFTER UNICOMPARTMENTAL KNEE ARTHROPLASTY

Abstract

Introduction and Aims Unicompartmental knee arthroplasty (UKA) is appropriate for one in three osteoarthritic knees requiring replacement. An accelerated protocol enables patients undergoing UKA to be discharged within 24 hours of surgery. Before such an approach is universally accepted it must be safe, effective and economically viable. A study was performed to compare the new accelerated protocol with current standard care in a state healthcare system.

Method A single blind RCT design was used. Patients eligible for UKA were screened for NSAID tolerance, social circumstances and geographical location before allocation to either an accelerated recovery group (Group A) or a standard non accelerated group (Group S). The accelerated protocol included dedicated pain management and discharge support. Primary outcome was the Oxford Knee Assessment at 6 months post operation, compared using independent t tests. Pain, range of movement and incidence of complications were also recorded by assessors blind to group allocation. Cost effectiveness was calculated in quality life adjusted years (QLAY) using the Euroqual instrument. The study power was sufficient to avoid type 2 errors. The study was supported by a NHS Regional R& D grant.

Results Forty one patients (21 group A, 20 group S) were included. Groups had comparable age and patient profiles. Average discharge time was 37 hours (1.5 days) for group A and 114 hours (4.3 days) for group S. Pain on hospital discharge was similar for both groups. No significant difference was found between groups for pain or range of movement at any time, although patients in group S regained pre-operative flexion faster than group A. One major complication occurred in each group; one infection (group S) and one manipulation for poor movement (group A). The cost per QLAY for the new protocol was 59% of the standard care.

Conclusion The new protocol allows for safe accelerated discharge from hospital after UKA. The approach is cost effective and should help to increase the throughput of patients who require knee replacement.