Apr 26, 2017Rethinking ACL Repair
According to an article from the Cincinnati Business Courier, more than 300,000 people in the United States require reconstruction after sustaining an ACL tear. A common approach has been to have patients undergo two grafting surgeries, ensuring stronger stability of the knee. But what if instead of needing two surgeries, athletes could return to play with excellent knee stability after just one?
Frank Noyes, MD, an Orthopedic Surgeon at Mercy Health Cincinnati, feels that an athlete shouldn’t have to undergo multiple surgeries to the knee unless it is absolutely imperative. Because of this, he conducted a research study to find out whether the second surgery is as necessary as many surgeons believe.
To carry out the investigation, Dr. Noyes built a robot that utilized software designed by Edward Grood, PhD, Emeritus Professor of Engineering at the University of Cincinnati. This software allowed the robot to put a cadaver knee through the same movements that would regularly be placed on a live athlete’s knee.
“Rather than performing a surgical procedure that we think will add more stability, we are using sophisticated testing in a laboratory setting to prove what technique adds more stability,” said Dr. Noyes in a press release from Mercy Health. “The robot – works with a cadaveric knee and provides precise scientific loading. It induces loads and torques in three dimensions, like a gyroscope, to measure displacement or the result of those loads.”
After testing the stability of the cadaver knee both with and without the original ACL, Dr. Noyes performed an ACL reconstruction using the robust patellar tendon graft and measured the stability of the cadaver joint once again. Dr. Noyes then performed a second graft to see if this extra step provided the stability that it is known for. Through this process, Dr. Noyes found that if the right type of graft is used in the first procedure, the likelihood of needing a second surgery is lessened.
“What our research found is that if you use a high-strength patellar tendon graft, it will provide the stability that allows the patient to return to normal activity without requiring the second graft,” said Dr. Noyes. “The key is that the graft needs to come from the patient’s own tissue. A cadaver ligament is not robust enough to allow patients to return to activities that require cutting and twisting movements. The graft also needs to be fixed precisely to provide this support.
“So we can tell our patients with a great deal of accuracy: I’m able to restore your normal stability to the knee joint with the type of surgery I’m recommending to you,” he continued.
However, Dr. Noyes does explain that about five percent of people will still require the second graft. This can be due to the patient having an atypical knee, needing extra support, or if the initial ACL graft fails. To combat failure, Dr. Noyes emphasizes the importance of a full recovery after undergoing ACL reconstruction. He explains that continued rehab is necessary for each patient, because 10 to 20 percent of athletes will re-tear their ACL due to returning to activity too quickly.
A full report on Dr. Noyes’ research was published in the April issue of the American Journal of Sports Medicine.