CC Nov 2015 Cruciate ligament injury

echoecho's version from 2015-11-16 01:08


Question Answer
What provides stability to the knee joint?a collection of muscles and ligaments
Within the joint, what two ligaments crisscross, connecting the distal femur to the proximal tibia?1) anterior cruciate ligament (ACL) 2) posterior cruciate ligament (PCL)
List the two functions of the ACL and PCL?1) prevent the femur and tibia from slipping on each other 2) provide some degree of reotational stability to the knee
Are ACL injuries usually traumatic or atraumatic?atraumatic
What is the mechanism of ACL injuries?patient plants their foot and turns sharply and feels a popping sensation and immediate swelling
Up to ____% of acute hemarthroses in athlethes are the result of ACL injuries?70
What 3 sports are ACL injuries more common in?1) soccer 2) football 3) basketball
List the 3 tests that can be used to diagnose ACL injury?1) Anterior Drawer test 2)Lachman Test 3) Pivot-Shift Test
Regarding the anterior drawer test, what is the positive likelihood ratio and the negative likelihood ratio?3.7; 0.6
How is the anterior drawer test performed?1) patient is supine 2) the hip is flexed to 45 degrees and the knee to 90 degrees while the foot stablized on the exam table 3) the lower leg is pulled anteriorly by the examiner, looking for movement of the tibia on the femur 4) a normal test is no more than 6-8 mm of laxity
Regarding the lachman test, what is the positive likelihood ratio and the negative likelihood ratio?12.4; 0.14
How is the lachman test performed?1) the patient is supine 2) the leg at the examiner's side \is slightly externally roted and flexed 3) the femur is stabilized with one hand and pressure is applied to the back of the knee with the other hand 3) a positive result is anterior movement of the knee with a soft endpoint
Regarding the Pivot-Shift test, what is the positive likelihood ratio and the negative likelihood ratio?20.3; 0.4
How is the Pivot-Shift test performed?1) the knee is fully extended and the foot is internally rotated 2) a valgus stress is applied to the knee while progressively flexing the joint, watching and feeling for translation of the tibia on the femur
*** Of the 3 tests, which of the test has the best positive predictive value and which test has the best negative predictive value for ACL inuries?1) Pivot-Shift test 2) Lachman test
Why are serial exams often needed?due to the difficulty of performing these manuevers after an acute injury
What is the imaging modality of choice (particularly if associated injuries like meniscal) are suspected?MRI
What treatments are recommended for minor strains?1) physical therapy 2) bracing
In the elderly with limited activity, how are they treated even if the ACL is completely torn?conservatively
Younger and active patients with a torn ACL require what treatment?surgery
Unlike the ACL, injuries to the PCL typically require more significant forces. List two examples?1) MVA collision 2) football player falling on a bent knee
Which are most common, ACL or PCL injuries?ACL
What test can be done to diagnose PCL injuries?posterior drawer test
How is the posterior drawer test performed?1) with the hip flexed at 90 degrees, the knee flexed at 90 degress and the foot stabilizied on the examination table 2) the tibia is forcibly pused posteriorly 3)detection of a sag when observed from the side is a positive test
Mild PCL injuries are treated with what?1) physical therapy 2) bracing
More significant PCL injuries require what treatment?surgery
*** SUMMARY = List the 3 tests that are useful for evaluation of anterior cruciate ligament injuries?1) Lachman 2) Pivot-shift 3) anterior drawer test
*** SUMMARY = What imaging modality is the imaging of choice?MRI
*** SUMMARY = Which is less common, ACL or PCL injuries?PCL
*** SUMMARY = ____ cruciate ligament injuries require surgical repair?PCL