Children's Hospital Colorado

ACL Rehabilitation and Recovery

An athletic trainer checks a young male athletes knee after a knee injury.

The anterior cruciate ligament (ACL) is one of the main stabilizing ligaments within the knee. It prevents the tibia (shinbone) from sliding forward on the femur (thighbone). It also helps prevent the tibia and femur from rotating out of position during various sports movements.

Research has shown that about one in every 60 young athletes will experience an ACL tear at some point during their athletic career. Unfortunately, these numbers are increasing due to the increased intensity of sports.

The importance of physical therapy after ACL surgery

ACL repair surgery will help you progress 10% of the way back to a healed ACL, but the remaining 90% of the work will be up to you through physical therapy. Each athlete's rehabilitation experience is different, and your length of recovery time will depend on your specific progress.

Our physical therapists (PTs) tailor their rehabilitation methods to your injury, progress and the demands of your sport. You must put in the work to be successful in rehabilitation so that you can safely return to your sport.

Our PTs focus on helping you regain strength, balance and range of motion after surgery. They also address faulty movement patterns that may contribute to the original injury itself. This approach helps decrease your risk of re-injury on the same side that you injured and assists with preventing additional injuries on the opposite side.

Components of ACL rehabilitation

If you break our rehabilitation approach down to a simple process, the physical components of ACL recovery and preparation for return to sport are:

  1. Get rid of the swelling in the injured knee.
  2. Get the motion back in the joint.
  3. Make the quadriceps work again.
  4. Walk normal.
  5. Recover the strength in the entire leg to be comparable with the other leg.
  6. Re-train balance, agility, symmetry of movement and the ability to move with explosive, quick patterns.
  7. Recover foot speed and every other skill your particular sport requires.

Timeline for ACL rehabilitation

To complete ACL rehabilitation thoroughly and safely, our sports medicine experts use a 9-12 month average timeframe for returning an athlete to their sport. While this process and timing will vary for each athlete, below is the typical timeline:

  • Change your dressing within 48 hours after your surgery. Make sure that your steri-strips remain intact.
  • Re-apply your ace bandage; this will help with swelling and will act as a barrier between the ice and your skin.
  • Schedule your first physical therapy visit (usually 5 to 7 days after your surgery).
  • Meet with your PT to summarize what to expect. Your PT will remove the compression sleeve and wrap around your knee; it's normal to have a swollen and bruised knee at this time.
  • Focus on reducing pain and inflammation, moving your knee and working on strengthening your quadriceps.

  • Slowly start to wean off the dependence on crutches and begin weight bearing as your PT directs.
  • Wear your brace at all times until you can perform 75 straight leg raises; this will ensure safety when you walk without your brace.
  • Continue to improve your range of motion between 0 to 90 degrees in the first two weeks, then up to 110 degrees by the third and fourth week.
  • You'll likely start core and hip training. Hip strength plays a crucial role in controlling your knee.
  • Ride the stationary bike to help your blood circulate around your knee; this will help the recovery process and increase your range of motion.
  • Start balance, stability and strength exercises as guided by your PT.

  • Biking should feel normal; increase resistance as your strength improves.
  • Continue to work on reducing swelling, regaining (and maintaining) range of motion and building strength in your legs, hips and core.
  • Remember to be aware of your body's pain and swelling and use this as a guide to how far you can push your limits.
  • Focus on improving your single leg so that it's similar to your other leg before you start running and jumping.
  • You should have your full range of motion returned by 10-12 weeks; this means getting your heel to your buttock just like your other side.
  • Your PT will determine when you're ready to run based on your strength and how well you can control your knee during specific exercises.
  • Typically at 3 to 4 months, you are fitted with your return-to-sport brace that should be worn whenever you run or jump outside of therapy.

  • During 4 to 9 months, focus on building strength in your quadriceps, hamstrings and hip stabilizers.
  • After sufficient strength is achieved, you will progress slowly to impact activities.
  • At Children's Colorado, you will progress through a jumping program in your home exercise program.
  • Work on regaining cardiovascular and muscular endurance to prepare for the physical demands of your sport.

  • At Children's Colorado, you must be cleared by your surgeon and PT before you can start playing sports again. This will usually require a test conducted by your PT to assess your strength, speed and how well you control your knee. The test typically covers demands that will be expected for your sport.
  • The return-to-sport test varies for each young athlete. You could take it anywhere between month 9 and 11 depending on your recovery process.
  • Once you're cleared to return to sports, it is important to return progressively. This means practicing for several weeks or months before you are ready to play in a game. Your PT will help you plan a safe return-to-sport progression depending on your sport, level and time of season.
  • Typically, we require that you wear your return-to-sport brace for at least one year with physical activity, and then gradually progress out of the brace pending your strength and comfort. Most patients will continue to wear their brace for two years after their surgery.
  • Remember to continue strength training at least 2-3 times per week, in addition to any practices or other sporting events you might have. This keeps your legs strong and helps reduce the risk of future injuries.
  • Continue working on is mental training and trusting your body and all the work you've put in throughout your rehabilitation process.

Getting back into the game takes patience

Prior to clearing you to return to your sport, our PTs will conduct the return-to-sports test once deemed appropriate. This test measures:

  • Endurance
  • Strength
  • Power production
  • Balance
  • Agility

In order to "pass" the return-to-sport test, the athlete must achieve more than 95% in each category when comparing the surgical side to the uninvolved side. Quality of movement and form is also assessed by the testing PT. The PT will discuss gradual progression back to sport(s) to help ensure that a safe return to the field or court is achieved.

Returning to your sport after recovering from your ACL injury will be exciting – athletes start to feel like themselves again. However, you, your coach and your team will all need to have patience and understand that getting back to playing as you did before, or even better, will take time.

Sports injuries and recovery don't just affect an athletes body, it can also take a mental toll on an athlete. Learn about the psychology of recovering from a sports injury.