Acute and Chronic Effects of Blood Flow Restriction Training in Physically Active Patients With Anterior Cruciate Ligament Reconstruction: A Systematic Review.

Context: Muscle atrophy and loss of knee function are common findings after anterior cruciate ligament (ACL) reconstruction. Rehabilitation through blood flow restriction (BFR) has gained clinical relevance when combined with low loads to improve these disorders in recent years.

Objective: To evaluate the rehabilitation effectiveness of ACL reconstruction with the use of BFR on pain, functionality, strength, and muscle mass in physically active people.

Data sources: A search of PubMed, Web of Science, and MEDLINE was performed on March 31, 2023, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines.

Study selection: Randomized clinical trials with active adults who underwent ACL surgery were included. They had to compare conventional treatments with the use of BFR, reporting values of pain, functionality, strength, or cross-sectional area (CSA). Articles whose participants presented concomitant injuries and whose intervention combined the use of BFR with treatments other than resistance training were excluded.

Study design: Systematic review.

Level of evidence: Level 2.

Data extraction: Study design, population, cuff pressure, and main outcomes including strength, quadriceps CSA, pain, and functionality.

Results: Six studies out of a total of 389 were included (152 participants; 90 men and 62 women). These included studies showed no differences on CSA or strength when comparing BFR training with high loads exercise. BFR has demonstrated improvements in knee functionality and pain compared with other interventions such as immobilization or high loads training.

Conclusion: The use of low loads combined with BFR improves pain, strength, functionality, and CSA. In addition, knee pain reduction and functionality are greater with BFR compared with the use of high loads or immobilization.