What’s the Difference Between ACL Tear and ACL Sprain?
An ACL (Anterior Cruciate Ligament) injury is a sprain or tear of the ACL that happens to most people while they play sports. Your ACL is a tissue band of ligaments that hold the knee bones together.
The function of the ACL is to prevent your shinbone (tibia) from sliding out in front of your thighbone (femur). Because of this, ACL injuries can be painful and debilitating.
There is a risk for an ACL injury in activities involving jumping and landing, sudden stops, or changes in direction (like in football and soccer).
Many patients noted that they remember hearing or feeling a “pop” in their knee at the time of the injury. Typically the knee will swell, feel unstable, and be too painful to bear weight.
For some, a mild ACL injury may be treated with rest and physical therapy. This combination may help you recover your knee stability and strength. In more severe cases, surgery may be needed to replace the torn ligament, followed by physical therapy.
The Difference Between an ACL Tear and ACL Sprain
An ACL injury is either a tear or sprain. An ACL tear is when the ACL is actually torn. The tear can be complete or partial. An ACL sprain is when the ACL is overstretched (but not torn).
ACL Injury Grades
The severity of the ACL injury is graded from 1 to 3.
Grade 1: The ligament is intact, and the joint is stable, but there is minimal stretching and some microscopic tearing of the ACL. Surgery is typically not needed.
Grade 2 (Partial Disruption): Some tearing has occurred, and there is a separation of the ligament fibers. There is moderate knee instability. This grade may or may not require surgery, based on the person’s activity level and the degree of instability.
Grade 3 (Complete Disruption): There is a complete tear in the ligament fibers. The ligament is completely disrupted, and there is an unstable knee joint. Surgery is usually needed.
Chances are you have an ACL tear if you heard a loud pop in your knee when you were injured, followed by swelling, pain, and knee instability.
Symptoms of an ACL Tear:
- Severe pain
- Rapid swelling
- A loud “popping” in the knee
- Knee instability where the knee feels like it will buckle and cannot support the weight
- Loss of range of motion
How to Diagnose an ACL Tear?
Your doctor will manipulate your knee to see if there is an ACL tear. Imaging tests, such as an MRI or X-rays (to rule out a fracture), may also be performed.
How to Prevent an ACL Tear?
You can help prevent an ACL tear by:
- Exercise training that strengthens your leg muscles and core lower abdomen, pelvis, and hips).
- Exercise training that develops the proper sports techniques and knee position for pivoting, cutting, jumping, and landing motions.
When Should You See a Doctor for an ACL Tear?
If you have injured your knee, or hear popping noises or other signs of an ACL injury, call your doctor right away to see how severe the injury is and to receive treatment.
OrthoArizona has 21 offices throughout the Valley, each focused on quality care, compassion, and excellent customer service. Since 1994, OrthoArizona has been dedicated to compassionate care of the highest quality.
Make an appointment today at one of our 21 locations across Arizona to start your healing journey.
The advice and information contained in this article is for educational purposes only and is not intended to replace or counter a physician’s advice or judgment. Please always consult your physician before taking any advice learned here or in any other educational medical material.