Anterior Cruciate Ligament (ACL) Injury

Symptoms of ACL Injury

Sudden and severe pain immediately following a knee injury is the most common complaint of an ACL injury. Other symptoms of an ACL injury include:

• A “popping” sound is often heard at the time of the injury

• Pain and tenderness along the joint line

• Decreased range of motion

• Difficulty or pain with weight-bearing

• Swelling and bruising of the affected knee

• Knee instability

To diagnose an ACL injury if present, Dr. Koscso will perform a comprehensive medical history and inquire about the events leading up to the injury. He will also perform a thorough physical examination including an evaluation for areas of pain and assessing knee range of motion and stability. Diagnostic imaging such as x-rays and magnetic resonance imaging (MRI) may be requested to confirm a diagnosis of ACL injury and identify any damage to other structures within the knee joint. For example, it is not uncommon for patients with ACL injuries to also injure surrounding structures such as the meniscus or articulating cartilage within the knee.

Non-Surgical Treatment

If a patient does not experience knee instability with an ACL injury, or if the ACL is not required for sports or daily activities for a particular patient, conservative therapy may be enough to successfully recover from an ACL injury. Avoiding weight-bearing with crutches and applying a knee brace can help the joint stabilize properly. A combination of RICE (rest, ice, compression, elevation) and non-steroidal anti-inflammatory medications can be used for pain management and reduce swelling associated with this injury. When the pain and swelling have dissipated, a physical rehabilitation program aimed at restoring muscle strength and range of motion becomes crucial. As stated above, imbalances in neuromuscular coordination with running, pivoting, jumping, and landing are often the largest modifiable risk factors for ACL injury, and a proper physical therapy program aims to improve this.

Surgical Treatment

In the event of a more severe or complex tear of the ACL, or if conservative therapy is unsuccessful, an arthroscopic ACL reconstruction may be necessary to restabilize the knee joint. This minimally invasive procedure involves a small camera (arthroscope) to visualize the muscles, tendons, and ligaments of the knee joint. Dr. Koscso uses specialized surgical instruments to excise the damaged fragments of the ACL that are then replaced with a tissue graft, either from the patient (autograft) or donor tissue (allograft). This arthroscopic procedure (as opposed to a traditional “open” procedure) provides a shorter recovery period for patients to return to their normal daily activities.

There are a number of important surgical considerations that go into performing an ACL reconstruction such as graft choice (autograft patellar tendon, quadriceps tendon, hamstring tendon or allograft tissue from a cadaver) and treatment of other potentially injured structures in the knee (meniscus, articular cartilage). These factors are addressed in a somewhat case-by-case basis after a careful discussion with the patient before surgery. A comprehensive surgical plan and discussion of risks, benefits, and expected recovery will be done at your visit with Dr. Koscso.

Insufficient left knee ACL after injury with gross laxity noted at the time of surgery (left). Successfully reconstructed left knee ACL with autograft tissue and appropriate tension (right).

Post-Operative Recovery

For a comprehensive reading of the expected post-operative recovery, including restrictions, physical therapy progressions, and return to work/sport guidelines after ACL reconstruction surgery, please see our corresponding protocol on our physical therapy protocols page.