The Effect of Blood Flow Restriction Exercise Prior to Total Knee Arthroplasty on Postoperative Physical Function, Lower Limb Strength and Patient-Reported Outcomes: A Randomized Controlled Trial.

UNLABELLED

The trial aimed to examine the effect of eight weeks preoperative low-load blood flow restricted resistance training (BFR-RT) on physical function, lower limb strength, and patient-reported outcomes in knee OA patients 3 and 12 months after total knee arthroplasty (TKA) compared with preoperative usual care. An assessor blinded randomized controlled trial (RCT) was conducted. Eighty-six patients scheduled for TKA who were allocated to 8 weeks BFR-RT on the affected leg 3x/week or preoperative usual care involving no exercise (CON).

PRIMARY OUTCOME

30-s sit to stand (30STS).

SECONDARY OUTCOMES

Timed Up&Go, 40-m walk test (40mWT), knee range of motion (ROM) 1-repetition maximum (1RM) leg press and knee extensor strength, maximal isometric contraction (MVIC) for the knee extensors and flexors, Knee injury and Osteoarthritis Outcome Score (KOOS), and Euroqol 5-dimensions (EQ-5D-L5) questionnaire. Data were collected at baseline (12 weeks pre-surgery), ~3 days pre-surgery, 3 and 12 months postoperatively. Intention-to-treat analysis revealed no significant between-group differences in the change from baseline to 3 and 12 months postoperatively on 30STS, TUG, or 40mFWT. Significant between-group differences were observed at 3 but not 12 months postoperatively for the corresponding changes in 1RM leg press strength, 1RM knee extensor strength, and MVIC knee extensor favoring BFR-RT. No between-group differences were observed for the delta changes from baseline in knee ROM, KOOS subscales or EQ-5D-L5 at any postoperative time points. These findings suggest that preoperative BFR-RT offered no superior effects compared with usual preoperative care on postoperative physical function or patient-reported outcomes. Preoperative BFR-RT produced amplified gains in lower limb muscle strength at 3 months postoperatively.

TRIAL REGISTRATION

NCT04081493.