When Can I Return To Sports After An Anterior Cruciate Ligament (ACL) Injury?

Question: When can I return to sports after an anterior cruciate ligament (ACL) injury?

Answer: This obviously is a very common question following successful anterior cruciate ligament reconstructive surgery or even after treating such an injury nonsurgically with brace and physical therapy. The question is always, "When can I return to my previous sport, etc.?"

Well, there's two important factors: One has to do with rehabilitation, and that is when will you be able to regain all of your motion and all of the strength in your knee as well as the skill we call proprioception or balance in your knee. And that has to do with working with a physical therapist, hitting your marks, getting your strength marks back, getting your balance back, etc. And people will recover that at varying levels.

What is not very variable is the healing of the ligament. And that ligament, once it's put in your knee, takes time to heal and to become a natural part of your body again. When you take it from a donor or from elsewhere in your knee it really is just a dead piece of tissue, and your body has to convert that into a living ACL ligament again. And that takes time.

So when is it safe along that healing phase or the healing curve of that ligament to return to sport? When is that ligament strong enough? Well, the standard or the gold standard for returning to sports is about six months. In other words, most surgeons if you question them across the country, will use six months as the hallmark for the graft, for the ligament being strong enough to withstand the rigors of a contact sport such as soccer, football, basketball or a cutting sport -- skiing, etc.

But, studies have shown, and certain surgeons have shown, that you can get the individual back sooner than that. In other words, based on the recovery of strength and motion in the knee as well as proprioception, some individuals have been able to return to sport as early as two months following the ligament surgery.

Obviously, if you are returning that soon to sports you are taking a greater risk with re-injuring the ligament because it's not as strong as it's going to be at six months or even a year. Even at six months it's not 100 percent strong, and we know that it might take up to two years for the graft to be fully incorporated or become a new ligament in your knee.

Should we make patients wait two years to get back to sports? Most of us feel that six months is a nice compromise between the graft being strong enough as well as not keeping the athlete out for a second season. So, most of us use the six-month period as a gold standard for returning to sports.

Sherwin Ho, M.D., The University of Chicago Medical Center Play