SAN ANTONIO -- Researchers at Brooke Army Medical Center are using a "tourniquet training" to help wounded warriors return to full health -- and they think it could change the way athletes recover from orthopedic injuries, as well.
Formally known as blood flow restriction (BRF) training, the technique could be a revolutionary shift in rehabilitation. A pneumatic surgical tourniquet -- similar to a blood pressure cuff -- is applied to the injured limb to partially restrict blood flow while the patient engages in strength training. Unlike traditional strength training methods that require high loads to make appreciable gains, this form of training is performed at very low resistance.
Johnny Owens, physical therapist and chief of human performance optimization at the Center for the Intrepid (CFI) at BAMC, who introduced the training to the facility, said the ability to train at low loads is precisely why it is so beneficial for wounded service members -- and possibly professional athletes looking to recover from injuries like torn ACLs, ruptured patellar tendons and damaged cartilage.
"Many of these warriors have severely damaged limbs due to blast injuries or burns, preventing them from participating in traditional forms of high load strengthening," Owens said. "BFR training allows them to gain strength and improve their function without compromising vulnerable joints or soft tissue."
Exercising with diminished blood flow is showing remarkable results, Owens said. He noted that researchers at BAMC are seeing improvements in both muscle girth and the work a muscle can perform in their patients undergoing BFR training. While individual results vary, patients are achieving an average of 50 to 80 percent strength gains in as little as a few weeks -- numbers previously unheard of in the world of muscular rehabilitation.
Once clinical trials of BFR training began at BAMC, the dramatic results were eye-opening for researchers. Colonel Don Gajewski, director of the CFI and an orthopedic surgeon, said he was skeptical initially about the treatment, which has its origins in Japan and is virtually unheard of in the United States. But after Owens brought several scientific papers published in Japan and Europe on the potential benefits to his attention, Gajewski wondered, "Why hasn't anybody tried this?"
"Our next thought was how this training could help the civilian world," Gajewski said. He pointed out that historically some of the most significant medical advancements have resulted from caring for those injured during conflict. While numerous traumatic orthopedic injuries that occur on the battlefield result in amputated or severely damaged limbs, others are similar to ones athletes typically face. BFR training may open the door in the sports world for those with potentially season- or even career-threatening injuries to recover more effectively.
"Hopefully the research bears it out," Gajewski said, "but if you extrapolate the outcomes, the potential is huge."
That has caught the attention of the NFL. Dr. Matthew Matava, head team physician for the St. Louis Rams and president of the NFL Team Physicians Society, said he is encouraged by BAMC's early results and believes BFR training could have practical application for players recovering from injury or surgery.
"The most beneficial aspect of this technique," said Matava, "may be the ability to improve muscle strength while avoiding the stress of high-resistance exercise in the early phases of rehabilitation."
While BFR training appears to hold promise in the sports medicine realm, Matava said he believes further research is necessary to evaluate any potential risks.
Owens said questions about the safety of applying a tourniquet during exercise are understandable. He is quick to point out, however, that this training is being done in a controlled, supervised environment with trained staff and specialized tourniquets that have safety measures built in, such as automatic shut-offs, the ability to ensure blood flow is not completely restricted and sensors to monitor ongoing pressure changes.
"We have done this training on over 200 patients," Owens said, "and we haven't had a single issue."
Although the exact mechanism is not fully understood, researchers have consistently found that the low oxygen state created by the tourniquet forces the body to use specific muscle fibers generally reserved for only the most strenuous tasks, such as sprinting or very heavy weight lifting. This signals the brain to release anabolic substances like human growth hormone (HGH), as much as 290 times greater than baseline.
Owens and his colleagues are engaged in ongoing research to study the effects of BFR training on various populations, including post-ACL surgery and post-arthroscopy of the knee. Most recently Owens submitted a $4 million grant for a multi-center clinical trial studying the effect of BFR training on patients post-fracture.
"One of the great things about our facility," Gajewski said, "is that everyone's focus is on the patients, our heroes, that we want to get back to action and our therapists are encouraged to innovate with that in mind."