The BEAR Procedure

At Deerfield and in youth sports across the country, anterior cruciate ligament (ACL) injuries are plaguing young athletic careers at increasingly alarming rates. The ACL is one of four major ligaments in the knee and is critical for gross stability of the knee joint. The Center for Disease control approximates that approximately 250,000 people in the United States tear their ACL annually and subsequently generates a healthcare cost of over $2 billion dollars. Unlike most of the other ligaments in the knee, the ACL cannot repair itself and patients need surgical intervention in order to regain normalcy in the joint. The current standard for an ACL reconstruction procedure consists of completely removing the torn ligament from the knee, harvesting a graft or a piece of living tissue from another tendon in the body like the hamstring or patella, and maneuvering the new graft to take the place of the old ACL. Although most patients regain full stability after rigorous physical therapy and rehabilitation, a significant percentage of patients also suffer surrounding muscle weakness, a graft rupture, and premature arthritis (painful inflammation and stiffness) on top of long recovery times that can range from 6 to 12 months. Dr. Martha Murray of Boston Children’s Hospital has set out to challenge the byproducts and long recovery time of the current ACL surgery by introducing the Bridge-Enhanced ACL repair (BEAR) procedure.

Murray’s BEAR procedure utilizes a bio-engineered sponge composed of special proteins which is stitched to both ends of the torn ACL. Her interest in ACL’s began when she was a materials science and engineering graduate student in the 1980s and in 1991, she began conducting research in Dr. Myron Specter’s lab at Harvard. The sponge, which acts as a bridge between the two torn ends of the ACL, is injected with the patient’s blood to stimulate healing of the ACL in and around the sponge. In order for the sponge to be stitched to both ends of the ACL, there must enough viable ACL to hold the sponge in place. If patients have enough of their ACL left to effectively receive the bridge treatment, there is convincing evidence that recovery time, risks of arthritis, and risk of complications due to harvesting graft from another part of the body are all severely reduced.

Dr. Murray’s exploration of this idea was housed early on by a Harvard University football players research initiative. Her research efforts have also been supported by the National Football League Players Association (NFLPA), Boston Children’s Hospital, and the National Institute of Health (NIH). From that, Dr. Murray founded MIACH Orthopaedics in 2016 which owns this ACL scaffolding sponge device. In September 2018, MIACH completed a series A investment round of 22.5 million dollars.

Dr. Murray ran phase 1 of the BEAR study in patients aged 18-35 with the requirement that they had 6-8mm left of their ACL, no knee damage other than an ACL tear, and no longer than 30 days out from their injury. In phase 2, the same patient requirements remained but Murray opened up the study pool to people with closed growth plates aged 14 to 35. Dr. Murray is currently working on phase 3 of the BEAR trial.

With the promise of the early clinical trials, Dr. Murray’s innovation could very well alter ACL the way the devastating injury is thought about forever. The BEAR procedure will continue to make strides to become the new standard for ACL surgery and hopefully, eventually reduce the heartache associated with the long and uncertain recovery time, early throbbing arthritis, and high risk of complications associated with the current ACL procedure.