Knee

Question 1

Describe the 3 Degree Classifications of laxity.

Answer 1

First Degree: minimal laxity noted (integrity of the ligament is intact) and End feel normal

Second Degree: moderate laxity (tearing of fibers), tensile strength of the ligament is compromised, and end feel present but not normal

Third Degree: severe laxity noted (no tensile strength), and Empty end feel

Question 2

How do you manage a MCL/LCL First Degree Sprain?

Answer 2

PRICE, pain free ROM, progressive strengthening and conditioning, +/- bracing

Question 3

How do you manage a MCL/LCL Second Degree Sprain?

Answer 3

Post-op splint or hinge brace, PRICE, pain free ROM, progressive strengthening and conditioning

Prognosis = good function with minimal to no laxity and return to participation after appropriate healing and function equal to uninvolved extremity

Question 4

How do you manage a MCL/LCL Third Degree Sprain?

Answer 4

Post-op splint or hinge brace, PRICE

Prognosis: isolated MCL = 5-7 week rehab

Question 5

What separates the deep portions of the MCL from the superficial portions?

Answer 5

a bursa

Question 6

What is the role of the deep layer of the MCL?

Answer 6

It helps with meniscal support and control

Question 7

What aids in the MCL’s opportunity for healing?

Answer 7

Its rich blood supply

Question 8

What’s the mechanism of injury for an ACL tear?

Answer 8

Hyperextension with IR of the leg with ER of the body, abrupt deceleration, strong quadriceps contraction/a force that drives tibia anterior

Question 9

When is the ACL’s anteromedial and posterolateral bundles taut?

Answer 9

anteromedial = taut throughout flexion

posterolateral = taut in extension

Question 10

During what range of motion does the ACL’s posterolateral bundle provide the greatest restraint to anterior translation?

Answer 10

From extension to about 20 degrees of flexion

Question 11

What are key predictors for increased potential for ACL injury in females?

Answer 11

Increased valgus motion and moments at the knee joint during impact phase of jump-landing tasks

Question 12

What’s the mechanism of injury for a PCL injury?

Answer 12

Posterior directed force on the tibia with knee flexed to 90 degrees. Can occur with varus/valgus in conjunction with MCL or LCL

Question 13

During what range does the PCL provide the most stability?

Answer 13

between 30-90 degrees of flexion

Question 14

When would the greatest posterior translation occur during ROM with a torn PCL? Why?

Answer 14

70-90 degrees because secondary restraints are too lax at that point to contribute to stability

Question 15

What education should be provided to those with an PCL injury?

Answer 15

To limit activities which place high loads to these joints since this could lead to pain and degeneration of the PF joint and medial compartment

Question 16

What are the goals of PCL rehab?

Answer 16

minimize posterior shear forces (protect healing tissue), quadriceps strengthening (synergistic to PCL), neuromuscular control (dynamic stability), and protect articular cartilage

Question 17

What does an isolated meniscal injury result from?

Answer 17

A combination of compression and rotation forces

Question 18

How would you non-operatively manage a Meniscal Tear?

Answer 18

PRICE, pain free ROM, progressive strengthening and conditioning, and functional activities

Question 19

Which meniscus would result in a quicker arthritic progression if torn?

Answer 19

The lateral meniscus

Question 20

In those that are younger, under 50, or active 50-60 year olds, what part of the meniscus would be a repairable tear?

Answer 20

longitudinal tears in the peripheral ⅓rd of the meniscus

Question 21

During rehab of a repairable meniscus, what is the primary caution? How long is the recovery?

Answer 21

Caution = loading in flexion

Recovery = 12+ weeks

Question 22

What influences patellar movement? (11)

Answer 22

• Muscles – quads, hip groups
• medial retinaculum / medial PF ligament
• patellar shape (a flat undersurface more likely to displace)
• height of patella (patella alta)
• shape and height of condyles
• VMO/VLO imbalance
• lateral retinaculum tightness
• Q angle ( normal up to10 degrees males, 16 females)
• hip factors (anteversion of the femoral neck results in squinting patella)
• tibial torsion
• foot mechanics

Question 23

What occurs during patellofemoral joint pain?

Answer 23

irritation of the nerve endings in the subchondral bone which occurs because of loss of normal energy-absorption function of the intermediate and deep zones of the articular cartilage

Question 24

What are the local, proximal, and distal factors that may cause patellofemoral pain?

Answer 24

• Local factor (Those related to the PF joint)
• Proximal factors (Those related to the hip and pelvis – dynamic Q angle)
• Distal factors (Those related to the foot and ankle – dynamic Q angle)

Question 25

What angles should you perform squats and knee extensions in to minimize patellofemoral stress during quad strengthening?

Answer 25

Squat = 45-0 degrees

Knee extension = 90-45 degrees

Question 26

For runners, what two adaptation to running form would decrease patellofemoral joint stress?

Answer 26

(1) a small degree increase in trunk lean
(2) shorter stride length

Question 27

Why do patellar dislocations occur?

Answer 27

Commonly as non-contact injuries secondary to combination of quadriceps contraction and angle of kne

Question 28

What injuries often occur along with a patellar dislocation? (3)

Answer 28

(1) tearing of medial stabilizing structures of knee (i.e. MPFL)
(2) articular cartilage damage
(3) osteochondral fractures

Question 29

What are the 3 most important structures of the posterolateral corner of the knee?

Answer 29

• Popliteus tendon
• Popliteofibular ligament
• Fibular collateral ligament