Anterior Cruciate Ligament Injury and Knee Anatomy

Vocabulary flashcards covering knee ligament anatomy, mechanisms of injury, vascular supply, and clinical examination findings for ACL tears and related knee injuries.

Anterior cruciate ligament (ACL)

A ligament that originates on the lateral femoral condyle and courses anteriorly and medially to insert on the anterior intercondylar area of the tibia, functioning primarily to prevent anterior motion of the tibia relative to the femur.

ACL tear

A ligament rupture commonly caused by sudden changes in direction or landing from a jump with excessive internal rotation or valgus stress, characterized by rapid-onset hemarthrosis, swelling, and excessive anterior translation of the tibia.

Middle geniculate artery

The arterial blood vessel that provides the primary blood supply to the anterior cruciate ligament (ACL).

Lachman test

A physical examination stability test used to assess for anterior laxity of the tibia relative to the femur, indicative of an anterior cruciate ligament (ACL) injury.

Tibial (medial) collateral ligament

A knee ligament that is most commonly injured by direct impacts to the lateral knee, presenting with laxity upon valgus stress testing.

Fibular (lateral) collateral ligament

A knee ligament that can be injured by a forceful blow to the medial knee while the leg is extended, presenting with laxity upon varus stress testing.

Oblique popliteal ligament

A wide, fibrous band connecting the posterior distal femur to the posterior proximal tibia, injury to which causes laxity during knee hyperextension.

Patellar ligament

A robust fibrous structure that represents the inferior projection of the quadriceps femoris tendon; injury to it results in impaired knee extension.

Posterior cruciate ligament

A knee ligament extending from the medial condyle of the femur to the posterior head of the tibia, injury to which results in posterior laxity of the tibia relative to the femur.