Author: Justin Thompson, MD
Co Author #1: George H. Canizares, MD
Co Author #2: Carlos R. Rodriguez, MD
Co Author #3: Nicholas D. Heathscott, MD

Patient Presentation:
Knee injuries are some of the most common joint related injuries documented in the literature. According to sources, approximately 40% of the injuries sustained occur at the knee joint. The knee is a complex joint that has multiple intricate parts that allow it to have multi-planar motion. The anatomical make up includes multiple ligaments, muscles, tendons, cartilage, and other soft/connective tissues. This is why so many different possibilities arise when our athletes come to us and say "my knee hurts." At that time, you should be considering some of the following questions: Did I see what happened? What did happen? Did someone else see the play? What was the mechanism of injury? Are they able to bear weight? Is the knee swollen? Is the knee stable? Did they tear a ligament?' The last question that is not always one of the first on your mind, however, considering the publicity surrounding the structure and negative outlook on return to play afterwards, consideration needs to be made that the first question on the mind of the athlete, fans, parents, and coaches is 'Is the ACL torn?'

History:
An 18 year-old college soccer player presented to the training room after a mid-season game. He stated that he was having posterior and lateral knee pain after getting slide tackled during a game. He reported that the tackle was from the outside and behind. He denied feeling any popping sensation, instability after the incident, or swelling. He was able to bear weight immediately, but was unable to finish that game secondary to pain. He did not practice prior to follow up. He was evaluated 5 days post injury. He reiterated that all his pain was posterior and lateral in his knee. He reported that he had not been practicing because the pain was limiting his running and knee range of motion. He denied any prior injuries to this knee. He reported there was no swelling at time of injury or anytime after.

Physical Exam:
General: NAD, calm, slow steady gait, slender and athletic build
CV: 2+ posterior tibialis bilaterally, warm extremities
Pulm: breathing comfortably on room air
GI: non-distended
Skin: No bruising, no swelling
Neuro: sensation grossly intact in lower extremities bilaterally
MSK:
Inspection: no deformity, appreciable swelling, or bruising
Palpation: pain with palpation of biceps femoris tendon insertion, no other muscle related discomfort, no pain along joint line, no bony tenderness, no patella pain with palpation or movement, no appreciable effusion on exam
ROM: Full AROM and PROM of knees, hips, and ankles bilaterally
Strength testing: 4/5 knee flexion on the right secondary to pain, 5/5 with knee flexion on left. 5/5 bilaterally with knee extension, hip flexion/adduction/abduction, ankle dorsiflexion/plantarflexion/inversion/eversion
Special testing: (+) R anterior drawer, R lever sign, R lachman.
(-) R varus stress at 0, R valgus stress at 0, McMurray's, Thessaly's; all L special tests negative as well

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