BACK TOTOP Browse A-ZSearchBrowse A-ZABCDEFGHIJKLMNOPQRSTUVWXYZ0-9 E-mail FormEmail ResultsName:Email address:Recipients Name:Recipients address:Message: Print-FriendlyBookmarksbookmarks-menuAnterior cruciate ligament (ACL) injuryCruciate ligament injury - anterior; ACL tear; Knee injury - anterior cruciate ligament (ACL)An anterior cruciate ligament injury is the over-stretching or tearing of the anterior cruciate ligament (ACL) in the knee. A tear may be partial or complete.Previous imagePlay SlideshowStop SlideshowNext image / Considerations The knee joint is located where the end of the thigh bone (femur) meets the top of the shin bone (tibia).Previous imagePlay SlideshowStop SlideshowNext image / Four main ligaments connect these two bones:Medial collateral ligament (MCL) runs along the inside of the knee. It prevents the knee from bending inward. Lateral collateral ligament (LCL) runs along the outside of the knee. It prevents the knee from bending outward. Anterior cruciate ligament (ACL) is in the middle of the knee. It prevents the shin bone from sliding out in front of the thigh bone. Posterior cruciate ligament (PCL) works with the ACL. It prevents the shin bone from sliding backward under the femur. Women are more likely to have an ACL tear than men.Related video goes here for no-HTML5 browsers Causes An ACL injury can occur if you:Get hit very hard on the side of your knee, such as during a football tackle Overextend your knee joint Quickly stop moving and change direction while running, landing from a jump, or turning Basketball, football, soccer, and skiing are common sports linked to ACL tears.Previous imagePlay SlideshowStop SlideshowNext image / ACL injuries often occur with other injuries. For example, an ACL tear often occurs along with tears to the MCL and the shock-absorbing cartilage in the knee (meniscus).Most ACL tears occur in the middle of the ligament, or the ligament is pulled off the thigh bone. These injuries form a gap between the torn edges, and do not heal on their own. Symptoms Early symptoms:A "popping" sound at the time of injury Obvious knee swelling within 6 hours of injury Knee swellingJoint swelling is the buildup of fluid in the soft tissue surrounding the joint or the joint itself.ImageRead Article Now Book Mark Article Pain, especially when you try to put weight on the injured leg Difficulty in continuing with your sport Feeling of instabilityThose who have only a mild injury may notice that the knee feels unstable or seems to "give way" when using it. First Aid See your health care provider if you think you have an ACL injury. Do not play sports or other activities until you have seen your provider and have been treated.Your provider may send you to get an MRI of the knee. It can confirm the diagnosis. It may also show other knee injuries.First aid for an ACL injury may include:First aidA ligament is a band of tissue that connects a bone to another bone. The anterior cruciate ligament (ACL) is located inside your knee joint and conn...ImageRead Article Now Book Mark Article Raising your leg above the level of the heart Putting ice on the knee Pain relievers, such as nonsteroidal anti-inflammatory drugs (for example, such as ibuprofen) You also may need:Crutches to walk until the swelling and pain get better Brace to give your knee some stability Physical therapy to help improve joint motion and leg strength Surgery to reconstruct the ACL Some people can live and function normally with a torn ACL. However, most people complain that their knee is unstable and may "give out" with physical activity. An unstable knee after an ACL tear can lead to further knee damage. You are also less likely to be able to return to the same level of sports if you have a torn ACL. Do Not Do NOT move your knee if you have had a serious injury. Do NOT use a splint to keep the knee straight until you see a provider. Do NOT return to play or other activities until you have been treated. When to Contact a Medical Professional Contact your provider right away if you have a serious knee injury.Get immediate medical attention if the foot is cool and blue after a knee injury. This means that the knee joint may be dislocated, and blood vessels to the foot may be injured. This is a medical emergency. Prevention Use proper techniques when playing sports or exercising. Some college sports programs teach athletes how to reduce stress placed on the ACL. This involves a series of warm up exercises and jumping drills. There are jumping and landing exercises that have been shown to reduce ACL injuries.The use of knee braces during vigorous athletic activity (such as football) is controversial. It has been shown to reduce the number of certain knee ligament injuries, but not specifically ACL injuries.Open ReferencesReferencesBolgla LA. Gender issues in ACL injury. In: Giangarra CE, Manske RC, eds. Clinical Orthopaedic Rehabilitation: A Team Approach. 4th ed. Philadelphia, PA: Elsevier; 2018:chap 49.Brotzman SB. Anterior cruciate ligament injuries. In: Giangarra CE, Manske RC, eds. Clinical Orthopaedic Rehabilitation: A Team Approach. 4th ed. Philadelphia, PA: Elsevier; 2018:chap 47.Cheung EC, McAllister DR, Petrigliano FA. Anterior cruciate ligament injuries. In: Miller MD, Thompson SR, eds. DeLee, Drez, & Miller's Orthopaedic Sports Medicine. 5th ed. Philadelphia, PA: Elsevier; 2020:chap 98.Gokeler A, Dingenen B, Hewett TE. Rehabilitation and return to sport testing after anterior cruciate ligament reconstruction: where are we in 2022? Arthrosc Sports Med Rehabil. 2022;4(1):e77-e82. PMID: 35141539 pubmed.ncbi.nlm.nih.gov/35141539/.Kalawadia JV, Guenther D, Irarrázaval S, Fu FH. Anatomy and biomechanics of the anterior cruciate ligament. In: Prodomos CC. The Anterior Cruciate Ligament: Reconstruction and Basic Science. 2nd ed. Philadelphia, PA: Elsevier; 2018:chap 1.Miller RH, Azar FM. Knee injuries. In: Azar FM, Beaty JH, eds. Campbell's Operative Orthopaedics. 14th ed. Philadelphia, PA: Elsevier; 2021:chap 45.AllVideoImagesTogKnee arthroscopy - illustration Knee arthroscopy is surgery that is done to check for problems, using a tiny camera to see inside your knee. Other medical instruments may also be inserted to repair your knee. Knee arthroscopyillustrationACL degrees - illustration An injury to the anterior cruciate ligament (ACL) may be described as a partial tear, complete tear or an avulsion (tearing away) from the bone attachments that form the knee.ACL degreesillustrationACL injury - illustration Anterior cruciate ligament (ACL) injuries may occur from coming to a quick stop with a directional change while running, pivoting, landing, or overextending the joint in either direction.ACL injuryillustrationNormal knee anatomy - illustration The ligaments which attach the upper leg bone (femur) to the large lower leg bone (tibia) create a hinge joint called the knee. The anterior and posterior cruciate ligaments are 2 short, strong ligaments which criss-cross each other in the middle of the joint.Normal knee anatomyillustrationAnterior cruciate ligament (ACL) injury - illustration Injury to the anterior cruciate ligament (ACL) is very common and usually the result of a twisting of the leg while applying full downward pressure.Anterior cruciate ligament (ACL) injuryillustrationAnterior cruciate ligament repair - seriesPresentation Knee arthroscopy - illustration Knee arthroscopy is surgery that is done to check for problems, using a tiny camera to see inside your knee. Other medical instruments may also be inserted to repair your knee. Knee arthroscopyillustrationACL degrees - illustration An injury to the anterior cruciate ligament (ACL) may be described as a partial tear, complete tear or an avulsion (tearing away) from the bone attachments that form the knee.ACL degreesillustrationACL injury - illustration Anterior cruciate ligament (ACL) injuries may occur from coming to a quick stop with a directional change while running, pivoting, landing, or overextending the joint in either direction.ACL injuryillustrationNormal knee anatomy - illustration The ligaments which attach the upper leg bone (femur) to the large lower leg bone (tibia) create a hinge joint called the knee. The anterior and posterior cruciate ligaments are 2 short, strong ligaments which criss-cross each other in the middle of the joint.Normal knee anatomyillustrationAnterior cruciate ligament (ACL) injury - illustration Injury to the anterior cruciate ligament (ACL) is very common and usually the result of a twisting of the leg while applying full downward pressure.Anterior cruciate ligament (ACL) injuryillustration Anterior cruciate ligament repair - seriesPresentation Self Care Anterior cruciate ligament (ACL) injury - aftercareCollateral ligament (CL) injury - aftercareMeniscus tears - aftercareRelated Information Knee arthroscopy(Surgery)ACL reconstruction(Surgery)ACL reconstruction - discharge (Discharge) Review Date: 6/17/2024 Reviewed By: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited. © 1997- All rights reserved. A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.Content is best viewed in IE9 or above, Firefox and Google Chrome browser.
Anterior cruciate ligament (ACL) injuryCruciate ligament injury - anterior; ACL tear; Knee injury - anterior cruciate ligament (ACL)An anterior cruciate ligament injury is the over-stretching or tearing of the anterior cruciate ligament (ACL) in the knee. A tear may be partial or complete.Previous imagePlay SlideshowStop SlideshowNext image / Considerations The knee joint is located where the end of the thigh bone (femur) meets the top of the shin bone (tibia).Previous imagePlay SlideshowStop SlideshowNext image / Four main ligaments connect these two bones:Medial collateral ligament (MCL) runs along the inside of the knee. It prevents the knee from bending inward. Lateral collateral ligament (LCL) runs along the outside of the knee. It prevents the knee from bending outward. Anterior cruciate ligament (ACL) is in the middle of the knee. It prevents the shin bone from sliding out in front of the thigh bone. Posterior cruciate ligament (PCL) works with the ACL. It prevents the shin bone from sliding backward under the femur. Women are more likely to have an ACL tear than men.Related video goes here for no-HTML5 browsers Causes An ACL injury can occur if you:Get hit very hard on the side of your knee, such as during a football tackle Overextend your knee joint Quickly stop moving and change direction while running, landing from a jump, or turning Basketball, football, soccer, and skiing are common sports linked to ACL tears.Previous imagePlay SlideshowStop SlideshowNext image / ACL injuries often occur with other injuries. For example, an ACL tear often occurs along with tears to the MCL and the shock-absorbing cartilage in the knee (meniscus).Most ACL tears occur in the middle of the ligament, or the ligament is pulled off the thigh bone. These injuries form a gap between the torn edges, and do not heal on their own. Symptoms Early symptoms:A "popping" sound at the time of injury Obvious knee swelling within 6 hours of injury Knee swellingJoint swelling is the buildup of fluid in the soft tissue surrounding the joint or the joint itself.ImageRead Article Now Book Mark Article Pain, especially when you try to put weight on the injured leg Difficulty in continuing with your sport Feeling of instabilityThose who have only a mild injury may notice that the knee feels unstable or seems to "give way" when using it. First Aid See your health care provider if you think you have an ACL injury. Do not play sports or other activities until you have seen your provider and have been treated.Your provider may send you to get an MRI of the knee. It can confirm the diagnosis. It may also show other knee injuries.First aid for an ACL injury may include:First aidA ligament is a band of tissue that connects a bone to another bone. The anterior cruciate ligament (ACL) is located inside your knee joint and conn...ImageRead Article Now Book Mark Article Raising your leg above the level of the heart Putting ice on the knee Pain relievers, such as nonsteroidal anti-inflammatory drugs (for example, such as ibuprofen) You also may need:Crutches to walk until the swelling and pain get better Brace to give your knee some stability Physical therapy to help improve joint motion and leg strength Surgery to reconstruct the ACL Some people can live and function normally with a torn ACL. However, most people complain that their knee is unstable and may "give out" with physical activity. An unstable knee after an ACL tear can lead to further knee damage. You are also less likely to be able to return to the same level of sports if you have a torn ACL. Do Not Do NOT move your knee if you have had a serious injury. Do NOT use a splint to keep the knee straight until you see a provider. Do NOT return to play or other activities until you have been treated. When to Contact a Medical Professional Contact your provider right away if you have a serious knee injury.Get immediate medical attention if the foot is cool and blue after a knee injury. This means that the knee joint may be dislocated, and blood vessels to the foot may be injured. This is a medical emergency. Prevention Use proper techniques when playing sports or exercising. Some college sports programs teach athletes how to reduce stress placed on the ACL. This involves a series of warm up exercises and jumping drills. There are jumping and landing exercises that have been shown to reduce ACL injuries.The use of knee braces during vigorous athletic activity (such as football) is controversial. It has been shown to reduce the number of certain knee ligament injuries, but not specifically ACL injuries.Open ReferencesReferencesBolgla LA. Gender issues in ACL injury. In: Giangarra CE, Manske RC, eds. Clinical Orthopaedic Rehabilitation: A Team Approach. 4th ed. Philadelphia, PA: Elsevier; 2018:chap 49.Brotzman SB. Anterior cruciate ligament injuries. In: Giangarra CE, Manske RC, eds. Clinical Orthopaedic Rehabilitation: A Team Approach. 4th ed. Philadelphia, PA: Elsevier; 2018:chap 47.Cheung EC, McAllister DR, Petrigliano FA. Anterior cruciate ligament injuries. In: Miller MD, Thompson SR, eds. DeLee, Drez, & Miller's Orthopaedic Sports Medicine. 5th ed. Philadelphia, PA: Elsevier; 2020:chap 98.Gokeler A, Dingenen B, Hewett TE. Rehabilitation and return to sport testing after anterior cruciate ligament reconstruction: where are we in 2022? Arthrosc Sports Med Rehabil. 2022;4(1):e77-e82. PMID: 35141539 pubmed.ncbi.nlm.nih.gov/35141539/.Kalawadia JV, Guenther D, Irarrázaval S, Fu FH. Anatomy and biomechanics of the anterior cruciate ligament. In: Prodomos CC. The Anterior Cruciate Ligament: Reconstruction and Basic Science. 2nd ed. Philadelphia, PA: Elsevier; 2018:chap 1.Miller RH, Azar FM. Knee injuries. In: Azar FM, Beaty JH, eds. Campbell's Operative Orthopaedics. 14th ed. Philadelphia, PA: Elsevier; 2021:chap 45.
