Quiz 6: 1

Question 1

What are the Ottawa knee rules?

Answer 1

1. Age over 55
2. Isolated tenderness of patella
3. Tenderness at fibular head
4. Inability to flex knee past 90˚
5. Inability to bear weight both immediately and in the ER (4 steps)

*Do #5 if all others are negative

Question 2

If the Ottawa knee rules are positive, what do these rules indicate?

Answer 2

Radiograph needed

Question 3

What are concomitant injuries seen with grade III MCL sprains?

Answer 3

1. Medial meniscus tear
2. Articular cartilage injury
3. Avulsion fx

Question 4

How much medial restraint does the MCL provide at 0˚ of knee extension?

Answer 4

57%

Question 5

What other structures help provide medial restraint at 0˚ of knee extension?

Answer 5

• ACL
• PCL
• ant/mid capsule
• posterior capsule

Question 6

Why do you perform testing at both 0˚ and 30˚ for the MCL?

Answer 6

To isolate the MCL from other structures

MCL makes up 78% of the medial restraints at 30˚ vs 57% at 0˚

Question 7

Most common MCL sprain MOI

Answer 7

Traumatic valgus force

Question 8

Compare ACL MOI to MCL MOI

Answer 8

• ACL is non-contact (no outside force)

- MCL generally involved contact

Question 9

What is the cluster of s/s for an MCL tear?

Answer 9

1. Pt describes MOI
2. Pt may describe “tearing” sensation
3. Pain
4. Pain with palpation over MCL

Question 10

Differentiate between sprain and strain

Answer 10

• Sprain: noncontractile tissue

- Strain: contractile tissue

Question 11

What is the AMA classification of knee instability testing and what type of laxity do you have with each?

Answer 11

1. Grade 1: mild sprain, no laxity
2. Grade 2: moderate sprain (1+, 2+)
3. Grade 3: severe sprain (3+)

Question 12

Grade 1 MCL sprain: laxity

Answer 12

None

Question 13

Grade 2 MCL sprain: laxity

Answer 13

Moderate
1+ = 1-5 mm more laxity than uninvolved side
2+ = 6-10 mm more laxity

Question 14

Grade 3 MCL sprain: laxity

Answer 14

Severe

3+ = more than 10 mm more laxity

Question 15

What special test can you do to test the MCL?

Answer 15

valgus stress test

Question 16

What is the first thing you should do to start the valgus stress test?

Answer 16

Go to varus position to close the joint

Question 17

Why do you need to move into varus position prior to valgus stress test?

Answer 17

To approximate the joint so you can palpate and kinesthetically feel it

Question 18

What should a positive valgus stress test in a younger person make you think?

Answer 18

Femoral epiphyseal plate injury

Question 19

If an epiphyseal plate injury is present, what is happening?

Answer 19

The ligament is stronger than the physis

Question 20

What is an additional comorbidity with an MCL valgus stress injury?

Answer 20

PF subluxation