New Research Confirms Best Practice for ACL Reconstruction

Mercy Health - Cincinnati, which provides advanced, quality, compassionate care in your neighborhood through its care network, announces that groundbreaking new research from orthopaedic surgeon and knee expert Frank Noyes, MD has confirmed best practice in patients undergoing anterior cruciate ligament (ACL) reconstruction following a tear or rupture.

The ACL serves as a knee stabilizer. It connects the thigh bone to the shin bone and works to prevent these bones from extending beyond a normal angle while also guarding against over rotation that causes giving way and knee instability. As many as 300,000 people in the United States and millions worldwide require ACL reconstruction surgery to restore stability to the knee following injury.

It has been common practice, particularly in Europe, for surgeons to perform two surgeries involving grafting ligaments on the inside and the outside of the knee to stabilize the joint.

With the aid of a robot and sophisticated software designed by University of Cincinnati professor Edward S. Grood PhD, University of Cincinnati College of Engineering, Dr. Noyes tested ACL reconstruction techniques to determine if the second graft was necessary for stability.

“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,” says Dr. Noyes. “The robot, funded by the Noyes Knee Institute and housed at The Jewish Hospital, 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.”

In other words, the robot puts a cadaver knee through the range of movement knees undergo in the real world to determine its stability across different loads and forces.

Dr. Noyes measured the stability of a normal knee and then removed the ACL to measure stability again. He then performed an ACL reconstruction using the robust patellar tendon graft and took stability measures. Next, he performed a second graft, an anterolateral ligament reconstruction, to test the common wisdom that it added extra stability.

“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,” says 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.”

He notes that about five percent of patients – those whose initial reconstructions have failed or who have knees that are atypical and need extra support – may require the second ALL graft in addition to the ACL graft.

The appropriate time to heal and rehabilitation focused building strength and flexibility in the muscles surrounding the knee are important factors in the patient’s recovery from ACL reconstruction using the patellar tendon graft.

“It’s unacceptable that 10-20% of patients will retear their ACL during what should be the healing period. Immediate rehab is necessary however the early return to sports is not the way to go,” says Dr. Noyes. “When we put in an ACL graft, it weakens in the initial healing process, with stability dropping from 100% to 30%. This is part of the healing process as the body begins to remodel the graft with strong collagenous tissue and it takes nine months to heal.”

Women can be more vulnerable to reinjury. Dr. Noyes adds that before returning to athletics, female athletes should undergo a special neuromuscular conditioning and strengthening program such as SportsMetrics to lessen the high reinjury rate and necessity for repeat ACL surgery.

The American Journal of Sports Medicine published Dr. Noyes’ research in January and it’s available here:  http://journals.sagepub.com/doi/abs/10.1177/0363546516682233?url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org&rfr_dat=cr_pub%3Dpubmed&