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Anterior Cruciate Ligament (ACL) Tear


The anterior cruciate ligament (ACL) is a cable-like structure made of collagen fibers in the center of the knee that attaches the femur to the tibia and stabilizes the knee joint to resist rotational forces.

The anterior cruciate ligament is most commonly injured during cutting, pivoting, or landing on a flexed knee with a planted foot. Patients may experience “classic” symptoms of a “pop” followed by immediate swelling, but these stereotypical indicators are not always present. Especially in females, an ACL tear can sometimes present after a twisting knee injury but with relatively little pain and swelling. That is why it is prudent for all significant knee sprains to be taken seriously and evaluated by a specialist. Once the anterior cruciate ligament tears, the knee may become unstable with rotational movements, so it is essential that an evaluation is performed, and a diagnosis made before the patient returns to sports or other high-risk activities. Allowing patients with ACL-deficient knees to experience recurrent instability episodes risks further damage to the menisci, articular cartilage, and other stabilizing structures. It predisposes to worsening instability and painful post-traumatic osteoarthritis.

Prompt diagnosis of ACL injury is paramount and involves a physical examination to assess indicators of laxity, including the anterior drawer test and Lachman test. Magnetic resonance imaging (MRI) is instrumental in evaluating the integrity of the anterior cruciate ligament fibers. Instrumented laxity tests in the office using devices such as the KT-1000 can help assess the functional status of the ACL, especially in cases of partial tears or when the MRI scan may be inconclusive.

Partial ACL tears or ACL sprains that result in minimally increased knee laxity can be treated nonoperatively with a period of rest and rehabilitation. However, for complete ACL tears that result in significant knee laxity in physically active individuals, anterior cruciate ligament (ACL) reconstruction surgery is usually the recommended treatment to stabilize the knee to restore athletic function and help protect the knee against damaging recurrent instability. Since, in most cases, the torn ligament is damaged beyond repair, reconstruction with a tendon graft is the standard approach. ACL reconstruction surgery involves drilling precisely-placed bone tunnels in the femur and tibia through which the surgeon places a tendon graft and secures it into place on either end. This tendon graft will then heal to the bone, functionally replacing the original anterior cruciate ligament. The surgeon can obtain graft tissue from the patient (autologous) or a tissue donor (allogenic). Familiar autologous graft sources are the patellar tendon, hamstring tendons, or quadriceps tendon. Common allogenic graft sources are the Achilles tendon and the tibialis anterior.

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I recieved Regenerative Injection Therapy on my right hip back in early March, 2018 from Dr. Meier. The result thus far have been very good - I have less pain and much better mobility. Dr. Meier and his staff are true professionals and have been great at setting expectations for the potential results of the Regenerative Injection Therapy process, making sure all my questions are answered in detail both before and after the procedure. I highly recommend Dr. Meier to anyone looking for alternatives to a hip replacement.

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