By Dr. Karim Meijer, Executive Director of Sports Medicine for CommonSpirit Health’s Mountain Region and Head Team Physician for the Denver Broncos
If you or your child plays a cutting or pivoting sport — think soccer, basketball, football, lacrosse, and skiing — it’s important to know the basics about ACL tears. As a longtime Head Team Physician for multiple NFL teams, including the Denver Broncos, as well as the Executive Director of Sports Medicine for CommonSpirit Health’s Mountain Region, I’ve seen and treated more ACL injuries than I can count. This overview is intended to help parents and athletes understand the ACL, including injury prevention, treatment and recovery.
If you or someone you care about needs ACL treatment, The Sports Center - CommonSpirit is the region’s leading sports medicine clinic. Visit our website or give us a call to learn more.
What is the ACL and why does it matter?
The ACL (anterior cruciate ligament) is a small but essential ligament inside the knee. Its job is to keep the shin bone (tibia) from sliding forward and to help control twisting of the knee. Even though it’s roughly the size of your pinky, when the ACL is damaged the knee can feel unstable and an athlete’s season — or even career — can be affected.
How ACL tears usually happen
Most ACL injuries are non-contact, meaning no one collides with the player. Typical situations include landing awkwardly from a jump, suddenly changing direction, or pivoting with the foot planted. You might hear a pop, feel the knee give out, and see quick swelling. Sometimes an athlete can even walk off the field, so don’t assume it’s a minor injury just because they can move.
Common signs of a torn ACL
- A loud “pop” at the time of injury
- Rapid swelling within a few hours
- Intense pain or the sensation that the knee “gave out”
- Difficulty bearing weight or feeling unstable
Immediate steps to take
Right after an injury, use the RICE method: Rest, Ice, Compression, and Elevation. Seek medical attention quickly — ideally from a sports medicine doctor or orthopedic surgeon. Early evaluation can help prevent further damage to the meniscus or cartilage. There is typically no need to go to the Emergency Room unless there is a loss of feeling, extreme pain that is unmanageable, or there is a deformity.
When you should call the doctor immediately
- You or your athlete heard a pop and the knee began to swell rapidly.
- Severe pain or inability to put weight on the leg.
- Sensation of instability or repeated giving way.
Early evaluation can start the right treatment and reduce additional damage.
What the doctor will check
Your clinician will do a physical exam (special tests like the Lachman and pivot-shift) and likely order imaging:
- X-rays to rule out fractures or to spot small bone fragments
- An MRI to confirm an ACL tear and to look for associated injuries such as meniscus tears or cartilage damage
Who’s most at risk?
Certain athletes have higher rates of ACL tears:
- Young athletes in pivoting sports
- Female athletes — statistics show higher rates among women in many youth and collegiate sports
- People with loose joints, knees that hyperextend, a high posterior tibial slope (a bone shape factor), or a family history of ACL tears
Why family history matters
Genetics play a big role. Studies show a strong familial pattern for ACL tears — if a parent or sibling had one, tell your doctor. That family history can change how your clinician assesses risk and recommends prevention.
Treatment choices: non-surgical vs. surgical
Deciding whether to take a surgical or non-surgical treatment route typically depends on the person’s age, activity level, and the knee’s overall damage.
Non-surgical: physical therapy and activity modification may be appropriate for less active adults or for some who don’t want surgery.
Surgical reconstruction: commonly recommended for young athletes who want to return to high-level sports or for those with other knee injuries that need repair.
If surgery is chosen, the torn ligament is replaced with a graft. Typical graft choices include:
- Bone–patellar tendon–bone (BTB): strong with bone-to-bone healing; sometimes causes mild anterior knee pain.
- Hamstring tendon: commonly used and effective; a bit more variable in size.
- Quadriceps tendon: gaining popularity; good size options and fixation methods.
- Donor (allograft): avoids a second surgical site but has higher failure rates in young active people—so it’s used selectively.
What to expect after ACL surgery
ACL surgery aims to restore knee stability. Many patients also have meniscus or cartilage work done at the same time. The surgery itself is only one part of recovery—the rehab that follows is critical.
Rehabilitation is a long, structured process. Note these key aspects of the rehabilitation process:
- Most athletes need between 9 and 12 months before returning to full sport, though some may be ready earlier if objective milestones are met.
- Rehab focuses on restoring strength (especially the quadriceps and hamstrings), balance, safe landing mechanics, and sport-specific skills.
- Return-to-play decisions are based on function and testing, not just the calendar — strength symmetry, movement tests, and confidence all matter.
Prevention tips for athletes and parents
You can reduce risk with consistent training and smart habits:
- Neuromuscular training programs teach safe landing, cutting, and deceleration mechanics.
- Strengthen hips, glutes, and legs to improve control during sports movements.
- Avoid year-round single-sport specialization too early; encourage balanced training and rest.
- If a family member had an ACL tear, ask about screening and targeted prevention programs.
Extra procedures and new ideas
For some high-risk cases — like repeated tears or severe rotational instability — surgeons sometimes add a lateral extra-articular tenodesis (LET). Studies suggest this can reduce re-injury risk for selected athletes. Other newer treatment options like platelet-rich plasma therapy, internal knee braces, and alternative repair techniques are still being studied and aren’t standard for everyone.
Summary
ACL injuries are serious but often treatable. With modern surgery (when needed), structured rehab, and smart prevention, many athletes return to the sports they love. Parents and players should prioritize prevention programs, full rehab, and careful return-to-play decisions.
Need help or have questions? If you’d like a referral, want to learn about injury-prevention programs, or have questions about ACL care, contact us at The Sports Center. We work with athletes and families to make informed choices and get players safely back in the game.
