Second ACL tear 7 times more likely in young athletes.

If you return to knee-strenuous sporting activities (e.g. soccer, volleyball) within 9 months of your ACL reconstruction and you are 25 years old or younger, you are 7 times more likely to sustain a second ACL tear!

Those who returned to their sport 12 months after surgery fared substanitially better.

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The reason is insufficient tissue healing and insufficient advanced physical therapy. Loss of an ACL changes knee joint function from a stable joint to a functionally and structurally unstable joint. With an intact ACL, appropriate feedback about motion (direction, magnitude of movement, speed and force) in the joint goes to the brain. The brain then puts this information together with other incoming data from your sight, your inner ear and muscles surrounding the joint and sends the correct impulses down to the correct muscles to do the correct contractions at the correct time to avoid instability and thus injury. Remove your ACL or replace your ACL with a tendon and this information is deficient and so the brain control mechanism is insufficient to provide functional stability and thus a second tear can occur.

Some examples of early to mid ACL rehab – the physical therapists at Custom Physical Therapy will decide when these are appropriate to use in your recovery based on their clinical expertise and knowledge of tissue healing properties as well as your individual progress.

The tendon that replaces your ACL remodels over a period of three years to actually become an ACL structurally. The stimulus for this remodeling is that the tendon is now performing the role of an ACL ligament and thus tissue structure changes to best suit the function required. The human body is truly amazing!

My message to you is to be patient with returning to knee intensive activities and to follow through with all your physical therapy. You should also be doing a very specific ACL rehabilitation physical therapy progression which not only involves regaining range of motion and muscle strength but also develops both static and dynamic balance. A progressive agility program must also be part of your recovery. Sports-specific training should also be completed before attempting to return to full activity.

Agility training in ACL rehabilitation is absolutely essential to avoid subsequent reinjury.

If you have any questions regarding your ACL injury or postoperative rehabilitation, feel free to call us at Custom Physical Therapy at 775-331-1199 or simply swing by to one of our 3 locations (see and ask to talk to a physical therapist.

We welcome your questions and even better, we would love to meet you!

By the way, a great resource for ACL specific as well as any other physical therapy questions is . Check it out!

Reference: JOSPT 50(2):83-91,2020