الفهرس 
Anatomy of the ACLOnly 14 pages are availabe for public view
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Abstract
The Anterior cruciate ligament (ACL) is the most commonly injured ligament in the knee. Most ACL tears occur in athletes by noncontact mechanisms versus contact mechanisms, such as rotational forces versus a direct hit to the knee. The most at-risk athletes for noncontact injury include skiers, soccer players, and basketball players, while the most at-risk athletes for contact injury are football players. (1)
There is no age or gender bias; however, it has been suggested that women are at increased risk of ACL injury secondary to a multitude of factors. Some studies suggest that females may have weaker hamstrings and preferentially utilize the quadriceps muscle group while decelerating. When engaging the quadriceps musculature while slowing down, this places abnormally increased stress on the ACL, as the quadriceps muscles are less effective at preventing anterior tibial translation versus the hamstring muscles. A second factor that may increase the risk of ACL injury is the increased valgus angulation of the knee. (2)
Typically, injury occurs during sports play that includes sudden changes in the direction of movement, rapid stopping, jumping and landing abnormally, a direct blow to the lateral aspect of the knee, or slowing down while running. (3)
The physical exam should include timing of the injury, mechanism of injury, ambulatory status, joint stability, mobility, strength, palpation and evaluation of possible associated injuries. Multiple maneuvers are employed to test the ACL and include the anterior drawer, the pivot shift, and the Lachman tests. These tests should be performed whenever there is suspicion of injury to the ACL. Although ACL injury can be diagnosed clinically, imaging with MRI is often utilized to confirm the diagnosis. MRI is the primary modality to diagnose ACL pathology with a sensitivity of 86% and specificity of 95%. (4)
ACL injuries, depending upon their severity, can be managed nonoperatively or operatively. In a recent study, 81% of those involved treated with ACL Reconstruction (ACLR) returned to some athletic activity, 65% returned to the preinjury level of competition, and 55% of high-level athletes returned to normal play and competition. Although, it has been reported that of those who undergo surgical repair, overall, 90% return to near-normal functioning. (Table 1) (5)