Dr. Ebraheim’s educational animated video describing the anatomy and associated injuries of the knee joint.
Disrupted quadriceps
•Patient is unable to actively extend the knee.
The most common cause of ACL ruptures:
•Traumatic force being applied during twisting motion.
•Side stepping or landing from a jump.
Patient complains of:
•Immediate pain
•Knee giving way
•Swelling
Aspiration of the knee
•If aspiration of the knee joint shows evidence of blood within the joint there is 7580% chance of ACL and meniscal injury.
Lachamn’s test ACL knee exam
•Knee is flexed at 30 degrees.
•ACL tear of the knee is identified by pulling on the tibia and examining the frontward motion of the lower leg in comparison to the upper leg.
Radiological exam – ACL
•MRI of the knee joint shows bone lesions or bruising associated with tears of the ACL. Injury is found in the typical location; middle of the femoral condyle and posterior part of the tibia laterally.
Posterior cruciate ligament tear (PCL)
•Common cause of injury is a bent knee hitting a dashboard in a car accident.
Tibial Sag Test –PCL knee exam
Quadriceps active testPCL knee exam
•The examiner stabilizes the leg of the patient and then the patient is asked to actively contract the quadriceps muscle.
•The tibia is seen actively reduced from the posterior subluxed position.
Lachman’s testPCL knee exam
•Knee is bent 2030 degrees.
•The posterior drawer test is carried out while the patient is in a supine position and the knee is flexed to 90 degrees.
•The amount of translation of the tibia relative to the femur is observed.
The dial test is performed while the patient is in the supine or prone position and both knees are in 90 and 30 degrees of flexion. More than 10 degrees of external rotation indicates significant injury.
Common meniscal tears
Symptoms include
•Knee pain
•Pain with straightening the knee
•Swelling
•Locking
•Weakness