Clinical Scenario: Knee pathologies often require rehabilitation to address the loss of knee-extensor (KE) strength, function, and heightened pain. However, in the early stages of rehabilitation, higher loads may be contraindicated. Blood flow restriction (BFR) resistance training does not require high loads and has been used clinically to promote strength improvements in a variety of injured populations. BFR resistance training may be an effective alternative to high-intensity resistance training during early rehabilitation of knee pathologies. Clinical Question: Following a knee injury, does BFR resistance training improve KE strength and function, and reduce patient-reported pain? Summary of Key Findings: Four randomized controlled trial studies met the inclusion criteria. Each included study evaluated the use of BFR resistance training on knee pathologies and the effects on KE strength, functional outcomes, and pain compared with high- or low-load resistance training. All 4 studies reported significant improvements in KE strength, function, and pain through a variety of outcome measures, following BFR resistance training use as the treatment. Clinical Bottom Line: There is consistent evidence to support the use of BFR resistance training as a treatment intervention following knee injury and as a means to improve KE strength and function and to reduce pain. Strength of Recommendation: Grade A evidence supporting the use of BFR resistance training for improvement in KE strength and function, and the reduction of patient-reported pain following an acute or chronic knee pathology.
