Everything We Know About Treating ACL and Tendon Injuries Is Wrong
After most MCL and ACL surgeries, doctors focus on treating and rehabbing the soft-tissue, while almost completely ignoring motor patterns and biomechanics
Outside's long reads email newsletter features our strongest writing, most ambitious reporting, and award-winning storytelling about the outdoors. Sign up today.
In the opening minutes of the 2006 AFC championship game between the Cincinnati Bengals and the Pittsburgh Steelers, Bengals quarterback Carson Palmer hurled a 66-yard pass to wide receiver Chris Henry. As Palmer released the ball, 299-pound Steelers tackle Kimo von Oelhoffen corralled Palmer’s left leg with his right arm, leaving the star quarterback writhing on the ground. The instant replay revealed a nausea-stirring inward collapse of the knee, which tore Palmer’s ACL.
In the off-season, Dustin Grooms, an intern trainer with the Bengals, watched as the team frantically tried to rehab Palmer’s shredded ligaments and cartilage. Grooms was baffled by their approach, which included ice, elevation, soft-tissue treatment, and strength work. They had millions of dollars at their disposal, yet the techniques they were using, says Grooms, “weren’t any different than what I’d seen done with college soccer players.” What’s more, the standard rehab protocol rarely seemed to restore complete stability to the knee. Reinjury was common. Palmer, for instance, despite his efforts, tore his ACL again in 2014.
Over the past few years, Grooms, now a 32-year-old professor of athletic training at Ohio University, has published a series of studies suggesting that for all joint injuries, standard physical therapy isn’t enough because it fails to address neuroplasticity, the process by which the brain rewires damaged neural connections. If rehabilitation doesn’t address weak spots left by that rewiring process, returning to the field can be risky. Following typical therapy, the best many athletes can hope for is a joint that’s weaker than it was before the injury; at worst, it will eventually require more time under the knife—nationally, ACL tears account for 350,000 surgeries each year.
The key to smooth and effective rewiring, says Grooms, is to apply a stress to brain pathways, which can improve a patient’s biomechanics. This involves things like sight-restricted lunges and targeted foam rolling, treatments you’re unlikely to get from most physical therapists.
Following typical therapy, the best many athletes can hope for is a joint that’s weaker than it was before the injury; at worst, it will eventually require more time under the knife.
“We’ve become tissue-ists,” says Kelly Starrett, a physical therapist whose clientele includes the New Orleans Saints, the U.S. Army’s Special Forces, Tour de France cyclists, and the San Francisco Ballet. “We’re really good at knee surgery and managing tissues after surgery.” Addressing motor patterns, Starrett argues, is just as important, but “insurance doesn’t incentivize a physical therapist to look at that.” The result, he says, is that the bad mechanics of healing tissues are never corrected, and they remain that way despite rehabilitation, degrading performance and making another injury likely.
There are a few clinical early adopters of the neuroplastic approach. Brad Cox heads the Acumobility clinic outside Boston and works with runners, triathletes, and Spartan Race competitors. This year, Cox used a custom foam roller to fix the running mechanics of American middle-distance Olympian Morgan Uceny after a back injury. “In the science literature it’s called neuromuscular repatterning,” Cox says. This involves stunningly painful exercises in which you tense up your quadriceps while plunging a lacrosse ball deep into a hip flexor. “It increases tension in larger muscle groups and along fascial lines,” Cox says. The upside is that smaller, unused muscles get reactivated. The downside is enduring a program that can feel like torture.
Grooms is experimenting with less painful approaches, including disrupting vision to reactivate latent sensory pathways. In an article in the Journal of Orthopedic and Sports Performance Therapy, Grooms and his colleagues elaborate on how the brain inefficiently relies on eyesight to stabilize an injured joint and how the process of confusing this loop with strobe glasses while rehabbing with drills, jumps, and exercises forces adaptation. “Your brain lets go of using vision to stabilize the joint and ramps up input from the remaining sensors,” Grooms says. As a result, the body relearns how to use muscles and tendons for stability.
It’s unlikely that insurance companies will cover this sort of rehab regimen anytime soon; the science on neuroplasticity is too new. But there’s interest from athletes—Grooms’s calendar is filling up with presentations at sports-medicine conferences, and Starrett’s book, Becoming a Supple Leopard, is a bestseller. Perhaps clinics like Acumobility will eventually lead physical therapy out of the RICE dark ages. Below are some tools to aid your recovery.
Acumobility’s Brad Cox begins the rewiring process by assessing where the restriction is. In the case of a torn ACL, this could mean foam-rolling quads with full body weight. From that rather uncomfortable position, a patient flexes and extends the leg for two minutes with the surrounding muscles tensed. Sounds easy, but this is where you enter the pain cave. After two minutes, pay attention to any differences in how it feels to move and any range of motion you may have recovered.
Dustin Grooms and his colleagues have produced good results by compounding movement therapies, such as multiplanar lunges, with the use of strobe glasses like those sold by MeyeND ($325). The intermittent visuals can decrease feedback to the nervous system, forcing the brain to “upregulate” the joint’s remaining mechanoreceptors, essentially bringing the nerve endings back online.
Kelly Starrett advocates a lower-tech approach. As soon as healing allows, he recommends daily body-weight squats, with a focus on perfect technique. “You can disrupt your vision’s involvement by doing one-legged squats with your eyes closed,” he says. “Or do them while you wash dishes.”