Q: Have you ever heard of someone with an ACL injury being called a "noncoper"? That's what I was referred to as today and it sounds like criticism to me. Is that what it means really?

A: We can see how a person might get this mistaken view of the term, so we're glad you asked and happy to set the record straight. Twenty-five years ago, it was decided to create something now known as the rule of thirds describing ACL patients. The break down is as follows:

One-third of all patients with ACL injuries will recover without surgery. They will be able to participate in recreational activities but not competitive sports. This group of patients is referred to as copers.
One-third (the noncopers) will require surgery to restabilize the knee.
And the remaining one-third were labeled the adapters referring to patients who get by without surgery. They adapt by modifying or lowering their activity level.
Copers are athletes who can go back to their preinjury level of sports without knee problems. They do not have episodes of the knee giving out from underneath them. And they are even able to perform activities requiring jumping, pivoting, cutting, and quick stop-start moves. Noncopers are unable to return to their previous level of activity and/or they report episodes of knee instability described as "giving-way."

Some research has been done trying to identify the differences between copers and noncopers. The difference is not related to whether or not the person is trying to get well versus not trying. Noncopers really do have significant objective findings to explain why they can't perform normal knee activities. Their quadriceps muscles are weak and the noncopers have decreased quadriceps control. They have more cocontraction of the quadriceps and hamstrings muscles (both contract at the same time), and significant changes in the way the knee moves.

Cocontraction is just one way the body has of automatically protecting an injured joint by increasing stiffness around the joint. This is an effective way to help the joint compensate for loss of ligamentous support. Some studies also showed that the way the quadriceps and hamstrings muscles contract during movement changes in noncopers.

Although surgery is not automatically needed just because you are a noncoper, this treatment approach is often recommended. Current evidence does not support the need for immediate surgery for all ACL tears. It is possible that even with ACL repair or reconstruction, the high-level of sports play will not protect the knee from future injuries. And there is some question whether this type of surgery really restores full stability and biomechanical function of the knee.

there's enough evidence to support a nonsurgical approach to ACL tears -- even for athletes who intend to return to full sports participation. Specific training programs that include strength training combined with perturbation (balance) training helps retrain the muscles (reducing cocontraction) and restores more normal knee motion. This type of training may eliminate the need for surgery for noncopers.

Right now there isn't a tool or test that can sort out one group from the other. But the idea is being investigated. In the future, the designation "coper" versus "noncoper" may be used to determine who needs surgery and who doesn't. Patients will be placed in one or the other category based on evidence-based predictive factors and treated accordingly. Having an ACL tear won't be a ticket straight into surgery for everyone involved in high-level sports.

Reference: Yonatan Kaplan, PT, MSc (Med). Identifying Individuals with an Anterior Cruciate Ligament-Deficient Knee as Copers and Noncopers: A Narrative Literature Review. In Journal of Orthopaedics & Sports Physical Therapy. October 2011. Vol. 41. No. 10. Pp. 758-766.