ACL Tear & Reconstruction – Knee Ligament Injury

The knee is a complex joint formed by three bones: the femur (thighbone), the tibia (shinbone), and the patella (kneecap), which moves in a groove on the femur. The knee relies on large muscle groups for strength and stability. The quadriceps muscles at the front of the thigh help extend the leg, while the hamstrings at the back bend the knee.

Four key ligaments connect the bones in the knee. The medial collateral ligament (on the inner side) and lateral collateral ligament (on the outer side) provide side-to-side stability. The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) cross inside the knee, controlling forward and backward movement and rotation. These ligaments keep the bones in proper alignment during movement.

Cartilage called menisci act as shock absorbers between the bones, and a thin tissue capsule surrounds the knee joint, lined with a synovial membrane that produces lubricating fluid. Proprioceptive nerve fibers in the ligaments and joint capsule help the body sense and control movement, enabling precise leg motions.

ACL tears often occur during quick, twisting movements of the knee, or when the knee is overextended or bent backward. These types of injuries frequently happen in sports that require sudden changes in direction or jumping, such as football, basketball, soccer, and skiing.

Female athletes have a higher risk of ACL tears than males, possibly due to differences in hip and leg alignment. Hormonal factors can also make ligaments more prone to injury. An ACL tear often comes with additional damage to the surrounding structures like the meniscus or cartilage, and sometimes even fractures.

After tearing an ACL, people often experience immediate pain, swelling, and knee instability. The knee may buckle or give out, making it difficult to straighten or walk. Significant swelling usually develops within hours of the injury.

If you suspect an ACL tear, see a doctor as soon as possible. A medical evaluation, including a physical exam and imaging tests like X-rays or an MRI, can confirm the diagnosis. The Lachman and Pivot Shift tests are commonly used to check for ACL integrity by assessing knee movement. X-rays will identify fractures, while MRIs provide detailed images of soft tissue damage.

Initial treatment for an ACL tear involves rest, ice, compression, and elevation (RICE) to reduce swelling and pain. Crutches or a knee brace may be recommended. Pain relief medication can also be prescribed.

Treatment plans vary depending on the severity of the injury and the patient’s lifestyle. Non-surgical options like physical therapy may be appropriate for partial tears or for patients who don’t require high levels of knee stability. Physical therapy focuses on strengthening the quadriceps and hamstrings to restore function.

Surgical reconstruction is often recommended for athletes, active individuals, or those with unstable knees. The surgery involves replacing the damaged ACL with a tendon graft, which can be sourced from the patient’s patellar tendon, hamstring, quadriceps, or a donor.

After surgery, physical therapy is crucial for recovery. It helps regain knee motion, strength, and stability, and most people can return to their regular activities within six months to a year.

Post-surgery recovery typically involves physical therapy, pain management, and careful monitoring of the knee’s progress. Walking aids like crutches are used at first, and patients gradually resume normal movement and strength training. Recovery times vary but most people regain functional movement within several months, with full activity possible after six months.