What is an ACL Tear?
The anterior cruciate ligament (ACL) runs through the knee from the front of the tibia (shinbone) to the back of the femur (thighbone) and is considered the main stabilizing ligament. The ACL is responsible for providing proper knee movement and preventing knee instability while performing athletic, work and everyday activities. An anterior cruciate ligament injury is common in the active population. An injury to the ACL can range from a mild sprain to a complete ACL tear. Dr. Jervis Yau, orthopedic knee specialist, specializes in diagnosing and treating ACL injuries in order to return Santa Barbara, Goleta, Santa Maria and Ventura, California patients to the activities they enjoy.
The ACL plays an important role within the knee joint by maintaining knee stability and providing protection to the two menisci of the knee. ACL injuries are commonly seen in sports such as skiing, football, basketball, soccer, tennis and gymnastics. ACL tears are typically a result of abnormal knee pivoting or twisting with the foot planted, but sometimes can occur from a direct blow. If not completely torn, the ACL can be stretched beyond its normal range, resulting in laxity of the ligament and persistent instability.
What are the Symptoms of an ACL Tear?
The symptoms of acute anterior cruciate ligament injury are pain, swelling, and stiffness of the knee joint. After the initial injury calms down, the most common complaint is that the knee buckles or shifts with certain movements (instability). Symptoms vary based on injury severity. A mild sprain may cause pain with limited swelling, while a severe ACL tear may cause a “popping” sound or sensation followed by significant swelling, pain and the inability to bear weight.
How are ACL Tears Diagnosed?
Dr. Yau will perform a complete medical review and physical examination to assess the injury severity and determine the level of knee instability. X-rays are commonly performed to rule out fractures, osteoarthritis and other potential knee injuries. Dr. Yau commonly recommends a MRI scan to confirm the diagnosis and evaluate for concomitant injuries.