The Anterior Cruciate Ligament (ACL) is a commonly torn ligament in the knee accounting for 20% of the knee injuries in young athletes. 50% of patients with an ACL injury have additional damage to other knee structures. ACL injuries send more athletes to the bench for longer periods than almost any other acute injury. These injuries occur most often in people who participate in high impact sports like tennis, basketball, football, skiing, soccer, and sports that requires abrupt changes in direction but can occur in non-sports related cases as well. Unfortunately, female athletes suffer more ACL tears than male athletes. These injuries also increase the risk of a subsequent knee injury and chronic knee problems like early onset osteoarthritis.
Knee anatomy and function
The anterior cruciate ligament (ACL) is one of the four major ligaments that stabilize the knee. The anterior and posterior cruciate ligaments (PCL)are located inside of the knee joint and cross each other to form an X. The ACL is in front, and the PCL is in the back of the knee. The ACL connects the femur (thighbone) to the tibia (shinbone) and helps keep the knee stable. The two collateral ligaments known as the medial collateral ligament (MCL) and the lateral collateral ligament (LCL) are found on the sides of the knee and restrain sideway knee motions.
What causes an ACL tear?
- Rapid changes in direction with the foot planted – cutting, pivoting, and sidestepping.
- Stopping suddenly.
- An awkward landing from a jump.
- Direct contact like a football tackle or a fall.
- 70% of ACL injuries occur without contact.
- 30% are the result of direct impact.
What are the symptoms of an ACL tear?
ACL tears are either partial or complete, although partial tears are rare. With a complete ACL tear, the ligament is split into two pieces or is torn off the bone. Patients often report hearing an audible pop and complain on the knee giving way or buckling. Other symptoms include pain, swelling, inflammation, bruising, tenderness along the joint, and difficulty with walking.
How is an ACL injury diagnosed?
Dr. Harrison will review your medical history and perform a thorough physical exam of your knee. He will carefully examine the injured knee and compare range of motion with the uninjured knee. Most ACL tears can be diagnosed with an orthopedic exam. However, Dr. Harrison may order imaging studies to confirm his diagnosis. These will include x-rays to examine the bones, and an MRI to view the soft tissues to diagnose the ligament damage. Dr. Harrison often aspirates the injured knee looking for blood in the fluid which indicates there is a high likelihood of an ACL tear. Your treatment options may vary with the severity of the injury and your needs and goals. If you have had imaging performed from an outside facility, please bring the imaging on a disk as well as any written reports. Dr. Harrison is unable to review or access this information.
Your ACL plays an essential role in the function of your knee and is a major stabilizer of the knee. Dr. Harrison has been in practice for over 24 years treating thousands of patients from all walks of life including high school, college, Olympic, and professional athletes. When you injure your ACL, contact Dr. Harrison to schedule a consultation.
Dr. Harrison is a board-certified fellowship trained orthopedic and sports medicine surgeon who specializes in arthroscopic knee and shoulder surgery. He is the Head Team Physician for the United States Alpine Ski Team and the Head Team Physician for Weber State University for over 20 years. Dr. Harrison completed his undergraduate degree at Baylor University and received his medical degree from the University of Arizona College of Medicine. He completed his orthopedic residency at the University of Utah followed by a fellowship in sports medicine at the Cincinnati Sports Medicine and Orthopedic Center. He finished his formal training with an additional AO Trauma Fellowship in Bern, Switzerland.
At a Glance
Dr. Jeffrey Harrison
- Board-Certified, Fellowship-Trained Orthopedic Surgeon
- Head Team Physician US Women's Alpine Team and Weber State University
- Performs over 800 surgeries per year
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