Blood Flow Restriction Enhances Recovery After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta‐analysis of Randomized Controlled Trials

Purpose To conduct a systematic review and meta‐analysis of randomized controlled trials (RCTs) evaluating neuromuscular and clinical outcomes of blood flow restriction (BFR) training after anterior cruciate ligament reconstruction (ACLR) compared with non‐BFR rehabilitation protocols. Methods A systematic review was performed in accordance with the 2020 Preferred Reporting Items for Systematic reviews and Meta Analyses guidelines by querying PubMed, MEDLINE, Scopus, the Cochrane Database for Systematic Review, and the Cochrane Central Register for Controlled Trials databases from inception through December 2023 to identify Level I and II RCTs evaluating outcomes of BFR training after ACLR compared with non‐BFR rehabilitation. A meta‐analysis was performed using random‐effects models with standardized mean difference (SMD) for pain, muscle strength, and muscle volume, whereas mean difference was calculated for patient‐reported outcome measures. Results Eight RCTs, consisting of 245 patients, met inclusion criteria, with 115 patients undergoing non‐BFR rehabilitation compared with 130 patients undergoing BFR after ACLR. Mean patient age was 27.2 ± 6.7 years, with most patients being male (63.3%, n = 138/218). The length of the BFR rehabilitation protocol was most commonly between 8 and 12 weeks (range, 14 days to 16 weeks). Most studies set the limb/arterial occlusion pressure in the BFR group at 80%. When compared with non‐BFR rehabilitation, BFR resulted in significant improvement in isokinetic muscle strength (SMD: 0.77, P = .02, I 2 : 58%), International Knee Documentation Committee score (mean difference: 10.97, P ≤ .00001, I 2 : 77%), and pain (SMD: 1.52, P = .04, I 2 : 87%), but not quadriceps muscle volume (SMD: 0.28, P = .43, I 2 : 76%). Conclusions The use of BFR after ACLR led to improvements in pain, International Knee Documentation Committee score, and isokinetic muscle strength, with variable outcomes on the basis of quadriceps strength, volume, and thickness when compared with non‐BFR rehabilitation. Level of Evidence Level II, systematic review and meta‐analysis of Level I and II studies.