Why it's done

Ligaments are strong bands of tissue that connect one bone to another. The ACL, one of two ligaments that cross in the middle of the knee, connects your thighbone (femur) to your shinbone (tibia) and helps stabilize your knee joint.

Most ACL injuries happen during sports and fitness activities that can put stress on the knee:

  • Suddenly slowing down and changing direction (cutting)
  • Pivoting with your foot firmly planted
  • Landing from a jump incorrectly
  • Stopping suddenly
  • Receiving a direct blow to the knee

A course of physical therapy may successfully treat an ACL injury for individuals who are relatively inactive, engage in moderate exercise and recreational activities, or play sports that put less stress on the knees.

ACL reconstruction is generally recommended if:

  • You're an athlete and want to continue in your sport, especially if the sport involves jumping, cutting or pivoting
  • More than one ligament or the cartilage in your knee is injured
  • You're young and active
  • The injury is causing your knee to buckle during everyday activities
Dec. 19, 2015
  1. Friedberg RP. Anterior cruciate ligament injury. http://www.uptodate.com. Accessed Oct. 10, 2015.
  2. Frontera WR. Anterior cruciate ligament tear. In: Essentials of Physical Medicine and Rehabilitation: Musculoskeletal Disorders, Pain, and Rehabilitation. 3rd ed. Philadelphia, Pa.: Saunders Elsevier; 2015. http://www.clinicalkey.com. Accessed Oct. 22, 2015.
  3. Knee arthroscopy. American Academy of Orthopaedic Surgeons. http://orthoinfo.aaos.org/topic.cfm?topic=A00299. Accessed Oct. 15, 2015.
  4. ACL injury: Does it require surgery? American Academy of Orthopaedic Surgeons. http://orthoinfo.aaos.org/topic.cfm?topic=A00297. Accessed Oct. 15, 2015.
  5. DeLee JC, et al. Anterior cruciate ligament injuries (including revision). In: DeLee & Drez's Orthopaedic Sports Medicine: Principles and Practice. 4th ed. Philadelphia, Pa.: Saunders Elsevier; 2015. http://www.clinicalkey.com. Accessed Oct. 22, 2015.
  6. Knee arthroscopy exercise guide. American Academy of Orthopaedic Surgeons. http://orthoinfo.aaos.org/topic.cfm?topic=A00300. Accessed Oct. 15, 2015.
  7. Shea KG, et al. The American Academy of Orthopaedic Surgeons evidence-based guideline on management of anterior cruciate ligament injuries. Journal of Bone and Joint Surgery. 2015;97:672.
  8. Stuart MJ (expert opinion). Mayo Clinic, Rochester, Minn. Oct. 28, 2015.