Anterior cruciate ligament (ACL) tearsare a common sports-related injury, and they often require surgical reconstruction. Without surgery, athletes with anACL tearmay have recurring problems withknee instability. Athletes with a torn ACL often feel like their knee is “giving way” or buckling, especially when playing sports that require cutting or pivoting maneuvers, such as soccer, basketball, or football.
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But does everyone who tears their ACL need surgery, and can your anterior cruciate ligament heal on its own once it has been torn?
The Injury and Recovery Process
After an ACL tear, the knee is usually swollen and painful. Patients who sustain this injury are uncomfortable and know they have a serious problem with the knee joint. The pain is often immediate, and many athletes can remember hearing a pop that occurs when their knee gives out and the ligament tears. The swelling typically occurs quickly, usually within a few hours, as the knee fills up with blood from the injury to the torn ligament.
Factors to Consider
Patients whosustain an ACL tearand then start to feel much better often wonder if they still need surgical reconstruction of the ligament. It can be hard to accept the rehabilitation needed after ACL surgery if the knee starts to feel good again. Rehab after an ACL reconstruction typically takes three to six months to return to full function. You may think the injury is not as severe as initially feared, and that perhaps it can heal with non-surgical treatment.
In the past, it was thought that a completely torn ACL has no chance of healing thoroughly. However, recent research has shown that occasionally the ACL can spontaneously heal over time, allowing the patient to return to high-level functioning with no knee instability. Whilenot everyone needs a functional ACLto perform their day-to-day or preferred activities, athletes who participate incertain sports that require pivoting maneuversdo require a fully functioning ACL. Typically, the ACL is repaired surgically. But it may also heal spontaneously over time.
Currently, there is no clinical prediction rule to figure out which patients will experience spontaneous healing and which will require surgical repair. Research indicates that some patients with spontaneous healing of the ACL experience a re-tear at a future time. That said, some patients with an ACL repair also experience re-injury to the ligament.
A Word From Verywell
After an ACL tear, your knee may begin to feel much better, but the decision for the next step in treatment should be based on other factors than how the knee feels. The more important considerations are theexamination findings, the MRI results, and your personal goals. Some people may choose to wait and see if the ACL heals, while others will want to quickly get into surgery to begin the ACL rehab process. It appears that non-surgical management certainly has a role in ACL treatment, so the decision to operate or not should be multi-factorial. A discussion with your surgeon regarding your expectations of treatment may be the best course of action.
5 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Diermeier T, Rothrauff BB, Engebretsen L, et al.Treatment after anterior cruciate ligament injury: Panther Symposium ACL Treatment Consensus Group.Orthop J Sports Med. 2020;8(6):2325967120931097. doi:10.1177/2325967120931097ACL injury: does it require surgery?. American Academy of Orthopaedic Surgeons.Anterior Cruciate Ligament (ACL) Tears. KidsHealth from Nemours. 2019.Wilk KE, Macrina LC, Cain EL, et al.Recent advances in the rehabilitation of anterior cruciate ligament injuries.Journal of Orthopaedic & Sports Physical Therapy. 2012;(42)3; 153-171.Roe, J, et al. “Spontaneous healing of the ruptured anterior cruciate ligament: A case series of 21 patients.” Orthopaedic Journal of Sports Medicine. 2016 July; 4(7): Suppl - 5.https://doi.org/10.1177/2325967116S00080Additional ReadingTambe AD, et al. “Anterior cruciate ligament insufficiency: does delay in index surgery affect outcome in recreational athletes.” Int Orthop. 2006 Apr;30(2):104-9.
5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Diermeier T, Rothrauff BB, Engebretsen L, et al.Treatment after anterior cruciate ligament injury: Panther Symposium ACL Treatment Consensus Group.Orthop J Sports Med. 2020;8(6):2325967120931097. doi:10.1177/2325967120931097ACL injury: does it require surgery?. American Academy of Orthopaedic Surgeons.Anterior Cruciate Ligament (ACL) Tears. KidsHealth from Nemours. 2019.Wilk KE, Macrina LC, Cain EL, et al.Recent advances in the rehabilitation of anterior cruciate ligament injuries.Journal of Orthopaedic & Sports Physical Therapy. 2012;(42)3; 153-171.Roe, J, et al. “Spontaneous healing of the ruptured anterior cruciate ligament: A case series of 21 patients.” Orthopaedic Journal of Sports Medicine. 2016 July; 4(7): Suppl - 5.https://doi.org/10.1177/2325967116S00080Additional ReadingTambe AD, et al. “Anterior cruciate ligament insufficiency: does delay in index surgery affect outcome in recreational athletes.” Int Orthop. 2006 Apr;30(2):104-9.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Diermeier T, Rothrauff BB, Engebretsen L, et al.Treatment after anterior cruciate ligament injury: Panther Symposium ACL Treatment Consensus Group.Orthop J Sports Med. 2020;8(6):2325967120931097. doi:10.1177/2325967120931097ACL injury: does it require surgery?. American Academy of Orthopaedic Surgeons.Anterior Cruciate Ligament (ACL) Tears. KidsHealth from Nemours. 2019.Wilk KE, Macrina LC, Cain EL, et al.Recent advances in the rehabilitation of anterior cruciate ligament injuries.Journal of Orthopaedic & Sports Physical Therapy. 2012;(42)3; 153-171.Roe, J, et al. “Spontaneous healing of the ruptured anterior cruciate ligament: A case series of 21 patients.” Orthopaedic Journal of Sports Medicine. 2016 July; 4(7): Suppl - 5.https://doi.org/10.1177/2325967116S00080
Diermeier T, Rothrauff BB, Engebretsen L, et al.Treatment after anterior cruciate ligament injury: Panther Symposium ACL Treatment Consensus Group.Orthop J Sports Med. 2020;8(6):2325967120931097. doi:10.1177/2325967120931097
ACL injury: does it require surgery?. American Academy of Orthopaedic Surgeons.
Anterior Cruciate Ligament (ACL) Tears. KidsHealth from Nemours. 2019.
Wilk KE, Macrina LC, Cain EL, et al.Recent advances in the rehabilitation of anterior cruciate ligament injuries.Journal of Orthopaedic & Sports Physical Therapy. 2012;(42)3; 153-171.
Roe, J, et al. “Spontaneous healing of the ruptured anterior cruciate ligament: A case series of 21 patients.” Orthopaedic Journal of Sports Medicine. 2016 July; 4(7): Suppl - 5.https://doi.org/10.1177/2325967116S00080
Tambe AD, et al. “Anterior cruciate ligament insufficiency: does delay in index surgery affect outcome in recreational athletes.” Int Orthop. 2006 Apr;30(2):104-9.
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