USMLE Step 1 Musculoskeletal and Derm
Knee Anatomy:
What does the ACL connect?
What does the PCL connect? ------- ✔ CORRECT ANSWER ✓✓What does the ACL connect?
- extends from the lateral femoral condyle to the anterior tibia
- prevents anterior translocation at the knee joint
What does the PCL connect?
- extends from the medial femoral condyle to the posterior tibia
Anterior Drawer Sign
What does it test for?
How do you perform it and when is it positive? ------- ✔ CORRECT ANSWER ✓✓What does it test
for?
- tear of the ACL
How do you perform it?
- bending knee at 90 degree, pull knee anteriorly
- increased anterior gliding of the tibia seen in ACL injury
Note:
,Lachman test is similar but at 30 degree angle
Posterior Drawer Sign
What does it test for?
How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
- torn PCL
How do you perform it?
- bend knee at 90 degree
- increased posterior gliding of tibia = PCL injury
Abnormal Passive Adduction of the knee (VALGUS stress test)
What does it test for?
How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
- tear of the MCL
How do you perform it?
- knee extended or at 30 degree, apply force laterally (VALGUS/external rotation) while
stabilizing knee
- if there is medial space widening --> MCL injury
Abnormal Passive Adduction of the knee (VARUS stress test)
What does it test for?
,How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
- tear of the LCL
How do you perform it?
- knee extended or at 30 degree, apply force medially (VARUS/internal rotation) while stabilizing
knee
- if there is lateral space widening --> LCL injury
McMurray Test
What does it test for?
How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
- meniscal injury/tear
How do you perform it?
- flexion and extension of knee with rotation of the tibia/foot
IF pain, "popping" on external rotation --> medial meniscal tear
IF pain, "popping" on interal rotation --> lateral meniscal tear
Knee Anatomy ------- ✔ CORRECT ANSWER ✓✓
What does it test for?
How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
How do you perform it?
What is the "unhappy triad" knee condition caused by?
, What is injured?
How does it present? ------- ✔ CORRECT ANSWER ✓✓What is the "unhappy triad" knee
condition?
- a common injury in contact sports due to lateral force applied to a planted leg
What is injured?
- classically consists of damage to the ACL, MCL and menial meniscus
- however, damage to the lateral meniscus is more common
How does it present?
- acute knee pain and signs of joint injury and instability
What is prepatellar bursitis?
What causes it? ------- ✔ CORRECT ANSWER ✓✓What is prepatellar bursitis?
- inflammation of the knee's largest sac of synovial fluid
What causes it?
- repeated trauma or pressure from excessive kneeling
What is a Baker's cyst? ------- ✔ CORRECT ANSWER ✓✓What is a Baker's cyst?
- popliteal fluid collection in the gastrocnemius-semimembranous burse
- commonly communicates with the synovial space and is related to chronic joint disease
Knee Anatomy:
What does the ACL connect?
What does the PCL connect? ------- ✔ CORRECT ANSWER ✓✓What does the ACL connect?
- extends from the lateral femoral condyle to the anterior tibia
- prevents anterior translocation at the knee joint
What does the PCL connect?
- extends from the medial femoral condyle to the posterior tibia
Anterior Drawer Sign
What does it test for?
How do you perform it and when is it positive? ------- ✔ CORRECT ANSWER ✓✓What does it test
for?
- tear of the ACL
How do you perform it?
- bending knee at 90 degree, pull knee anteriorly
- increased anterior gliding of the tibia seen in ACL injury
Note:
,Lachman test is similar but at 30 degree angle
Posterior Drawer Sign
What does it test for?
How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
- torn PCL
How do you perform it?
- bend knee at 90 degree
- increased posterior gliding of tibia = PCL injury
Abnormal Passive Adduction of the knee (VALGUS stress test)
What does it test for?
How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
- tear of the MCL
How do you perform it?
- knee extended or at 30 degree, apply force laterally (VALGUS/external rotation) while
stabilizing knee
- if there is medial space widening --> MCL injury
Abnormal Passive Adduction of the knee (VARUS stress test)
What does it test for?
,How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
- tear of the LCL
How do you perform it?
- knee extended or at 30 degree, apply force medially (VARUS/internal rotation) while stabilizing
knee
- if there is lateral space widening --> LCL injury
McMurray Test
What does it test for?
How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
- meniscal injury/tear
How do you perform it?
- flexion and extension of knee with rotation of the tibia/foot
IF pain, "popping" on external rotation --> medial meniscal tear
IF pain, "popping" on interal rotation --> lateral meniscal tear
Knee Anatomy ------- ✔ CORRECT ANSWER ✓✓
What does it test for?
How do you perform it? ------- ✔ CORRECT ANSWER ✓✓What does it test for?
How do you perform it?
What is the "unhappy triad" knee condition caused by?
, What is injured?
How does it present? ------- ✔ CORRECT ANSWER ✓✓What is the "unhappy triad" knee
condition?
- a common injury in contact sports due to lateral force applied to a planted leg
What is injured?
- classically consists of damage to the ACL, MCL and menial meniscus
- however, damage to the lateral meniscus is more common
How does it present?
- acute knee pain and signs of joint injury and instability
What is prepatellar bursitis?
What causes it? ------- ✔ CORRECT ANSWER ✓✓What is prepatellar bursitis?
- inflammation of the knee's largest sac of synovial fluid
What causes it?
- repeated trauma or pressure from excessive kneeling
What is a Baker's cyst? ------- ✔ CORRECT ANSWER ✓✓What is a Baker's cyst?
- popliteal fluid collection in the gastrocnemius-semimembranous burse
- commonly communicates with the synovial space and is related to chronic joint disease
