NCT04917952

Effectiveness of Blood Flow Restriction Exercise Therapy to Reduce Pain in Knee Osteoarthritis Patients

Effectiveness of Blood Flow Restriction (BFR) Exercise Therapy to Reduce Pain in Knee Osteoarthritis (OA) Patients. A Double-blinded Randomised Clinical Trial

• Status: Unknown
• Phase: N/A
• Study type: Interventional
• Enrollment: 42 (estimated)
• Sponsor: University of West Attica · Academic / Other
• Sex: All
• Age: —
• Healthy volunteers: Not accepted

Summary

Resistance training of knee extensor muscles is being used in physiotherapy management in knee osteoarthritis (OA) to improve pain and physical function. Blood flow restriction (BFR) has been suggested to improve pain and increase muscle strength in healthy subjects and certain diseases. Although there are clinical studies suggesting improvements in knee osteoarthritis symptoms after 4-12 weeks of exercise with BFR, the acute effects of the intervention have not been known. This study aims to assess the effectiveness of low load exercise therapy combined with BFR on acute pain reduction and within 24 hours post-intervention on people with knee OA compared to a placebo group. This study will take place in Athens, Greece, as part of the postgraduate MSc program of the Physiotherapy department of the University of West Attica.

Detailed description

A double-blinded randomised clinical trial with a total of 42 participants will be randomly assigned to the intervention (n=21) or the control group (n=21). The intervention group will complete a single exercise session with BFR 80%, 30% 1RM, while the control group will have sham BFR, 30% 1RM. Pain Pressure Threshold (PPT) will be assessed with the use of a digital pressure dynamometer.

Conditions

• Knee Osteoarthritis

Interventions

Type	Name	Description
DEVICE	Blood Flow Restriction (BFR)	* Exercise: Bilateral knee extension at range 90ο-0ο * Load: 30% 1RM * BFR: Yes, 80% at both legs * Sets: 4 * Reps: 30-15-15-15 * Rest: 30'' between sets * Tempo: 2-0-2-0 Participants of the intervention group will receive an exercise protocol with blood flow restriction once and will be measured for changes in PPT by the use of a digital dynamometer. Exercise protocol will be four sets of bilateral knee extension 90ο-0ο, reps per set 30-15-15-15, tempo 2-0-2-0 and rest 30 sec between sets. In order to determine the training load 30% of 1RM, participants will perform bilateral knee extension in range 90ο-0ο with pain-free maximum resistance. The derived 1RM will be used to determine the 30% 1RM load. Blood flow restriction will be applied at 80% by using pressure cuffs. The cuffs will be applied to the proximal thigh. Cuff pressure needed for a 100% vascular occlusion will be determined for each individual at a seated and relaxed position.
DEVICE	Sham Blood Flow Restriction (sham BFR)	* Exercise: Bilateral knee extension at range 90ο-0ο * Load: 30% 1RM * BFR: Yes, Sham BFR, 10mm Hg at both legs * Sets: 4 * Reps: 30-15-15-15 * Rest: 30'' between sets * Tempo: 2-0-2-0 Participants of the control group will receive an exercise protocol with sham blood flow restriction once and will be measured for changes in PPT by the use of a digital dynamometer. Exercise protocol will be four sets of bilateral knee extension 90ο-0ο, reps per set 30-15-15-15, tempo 2-0-2-0 and rest 30 sec between sets. In order to determine the training load 30% of 1RM, participants will perform bilateral knee extension in range 90ο-0ο with pain-free maximum resistance. The derived 1RM will be used to determine the 30% 1RM load. Sham technique for blood flow restriction will be applied by using pressure cuffs inflated at 10mm Hg. The cuffs will be applied to the proximal thigh. Cuff pressure will be applied for each individual at a seated and relaxed position.

Timeline

• Start date: 2021-06-01
• Primary completion: 2021-08-01
• Completion: 2021-08-01
• First posted: 2021-06-08
• Last updated: 2021-06-08

Regulatory

• FDA-regulated device study