A 17-year-old competitive female athlete reported injuring her knee while participating in a soccer game. On the field, she attempted to execute a cutting maneuver when an opponent collided slightly with her trunk and throwing her off balance. She felt a "pop" in her right knee and an immediate sensation of her knee "giving way." She was unable to continue playing and was removed from the game. On the sideline, you observe significant effusion in the suprapatellar region. The patient reports difficulty bearing weight on the right lower extremity due to pain and lack of muscle control.
Based on the patient's suspected diagnosis, what do you anticipate may be the contributing factors to her condition?
What examination signs may be associated with this diagnosis?
FUNCTIONAL INSTABILITY: Sensation of "giving way" due to excessive motion and/or translation within the knee joint or inadequate neuromuscular stability within the lower extremity
MECHANICAL INSTABILITY: Increase in translation of the knee joint due to ligamentous insufficiency
Describe the anatomic structure and function of the anterior cruciate ligament (ACL).
Identify potential secondary injuries that may occur at the time of an ACL injury and how these could affect rehabilitation prognosis.
Describe clinical tests with acceptable diagnostic accuracy to identify ACL laxity.
PT considerations during examination of the individual with suspected acute anterior cruciate ligament insufficiency:
- General physical therapy plan of care/goals: Decrease pain and effusion; increase muscular strength; increase lower quadrant strength; improve functional stability; prevent or minimize loss of aerobic fitness capacity
- Physical therapy tests and measures: Lachman examination, pivot shift examination
- Differential diagnoses: Patellar dislocation, osteochondral injury
Acute injury to the anterior cruciate ligament (ACL) is common in pivoting and cutting activities. As many as 200,000 to 300,000 ACL injuries occur each year in the United States.1,2 A thorough clinical assessment and diagnosis is critical for early treatment plan development.
The primary role of the ACL is to create stability in the knee joint. The ACL attaches distally in the knee joint on the tibial plateau, anterior to the medial tibial spine.3,4 The ACL ascends in a posterior lateral direction to its femoral attachment along the posterior inner surface of the lateral femoral condyle (Fig. 25-1).3,4 Functionally, the ACL comprises two functional bundles that provide mechanical stability through a full arc of motion.1 The anterior medial bundle (AMB) is taut in a flexed position, while the posterior lateral bundle (PLB) tends to be taut in full extension.2 Some authors discuss a third intermediate bundle whose functional contribution is significantly less than the AMB and PLB.2 Together, these bundles assist to create mechanical stability in the knee. Primarily, the ACL provides restraint to anterior tibial translation and assists in rotatory stability in the knee.3...