Knee injuries

Question 1

Unhappy triad is the damage to which ligaments following a lateral blow to the knee?

Answer 1

anterior cruciate ligament
medial collateral ligament
meniscus (classically the medial meniscus but recent evidence shows that the lateral meniscus is more commonly injured)

Question 2

Which injuries damages ACL and which tests do you do to find out

Answer 2

Twisting injuries

Anterior drawer test and Lachman test

Question 3

Posterior cruciate ligament - how do the injuries occur

Answer 3

Damage following dashboard injuries

Question 4

MCL how do injuries occur

Answer 4

Damage result from skiing and following valgus stress

Damage causes abnormal passive abduction of the knee

Question 5

If the knee locks and gives way- what damage is done?

Answer 5

Damage to the Menisci

Question 6

Knee pain- ACL features

Answer 6

More common in women
Instability: feels like knee will give way
- Anterior draw test: knee at 90 degrees
- Lachman’s test: knee at 30 degrees- more reliable than anterior draw test

Question 7

Knee pain- meniscal tear features

Answer 7

Typically from twisting injuries
pain worse on straightening the knee
knee may ‘give way’
displaced meniscal tears may cause knee locking
tenderness along the joint line
Thessaly’s test - weight bearing at 20 degrees of knee flexion, patient supported by doctor, postive if pain on twisting knee