The ACL is a band of regularly oriented connective tissue that connects the femur and tibia. It is narrow in the middle, fanning out inferiorly, and to a lesser extent, further superiorly. The ACL passes from the anterior tibia to the posterior part of the inner aspect of the lateral femoralcondyle. The femoral attachment is in the form of a circle.
The ACL prevents anterior displacement (forward movement) of the tibia in relation to the femur, eg. preventing hyperextension, as well as providing a check to rotation at the knee joint.
Mechanism of Injury
Rotation or flexion (knee bend) injury.
May be direct trauma or excessive stresses from landing from a jump or rapid deceleration.
The patient may have sudden pain or hear a ‘pop’.
The knee may give way at the time of injury and/or have a recurrent ‘giving way’ problem after the injury.
After the initial trauma and associated pain, the athlete can often walk off the field even if it is a complete rupture.
Onset of swelling is rapid; it is the result of hemarthrosis (blood in the joint).
The active and passive ranges of motion may be limited.
Please consult with your medical professional for a complete diagnosis and treatment plan.