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631: Clinical Management of the Musculoskeletal System I > Knee > Flashcards

Flashcards in Knee Deck (117):
1

What are the 2 joints of the knee?

- Tibiofemoral joint
- Patellafemoral joint

2

What are the 3 most common types of knee injuries seen clinically?

- Unspecified sprains, strains or overuse injuries
- Contusions
- Meniscal or ligamentous injuries

3

Which knee joint is the largest joint in the body?

the tibiofemoral joint

4

The tibiofemoral joint has _ degrees of freedom, what are they?

3:
Flexion/Extension
Internal Rotation/External Rotation
Abduction/Adduction

5

The lateral condyle serves as the origin of what 3 structures?

- Popliteus
- Lateral head of the gastrocnemius
- Lateral collateral ligament (LCL)

6

The medial condyle serves as the origin of what 3 structures?

- Adductor magnus
- Medial head of the gastrocnemius
- Medial collateral ligament (MCL)

7

Tibial plateaus are con___ in the mediolateral direction

concave

8

The medial tibial plateau is con___ in the A/P direction

concave

9

The lateral tibial plateau is con___ in the A/P direction

convex

10

Does the medial or lateral tibial plateau have a larger surface area? How much larger is it?

The medial plateau has a surface area that is approximately 50% greater than that of the lateral plateau

11

Medial plateau’s articular surface is __ times thicker than the lateral plateau's

3

12

The presence of what accentuates the concavity of the tibial plateaus?

the menisci

13

What is the resting position of the tibiofemoral joint?

25 degrees of flexion

14

What is the closed-packed position of the tibiofemoral joint?

Full Extension and External Rotation of the Tibia

15

What is the capsular pattern for the tibiofemoral joint?

Flexion > Extension

16

What type of joint is the patellofemoral joint?

Modified plane joint

17

The patella has _ facets. What are they?

5:
Odd
Superior
Inferior
Medial
Lateral

18

Which patellar facet is most frequently affected with chondromalacia patella?

the odd facet

19

What are the 5 functions of the patellofemoral joint?

- Provide the articulation with low friction
- Protect the distal aspect of the femur from trauma and the quadriceps from attritional wear
- Improve the cosmetic appearance of the knee
- Improve the moment arm (distance between the center of gravity and the center of rotation) of the quadriceps
- Decrease the amount of A/P tibiofemoral shear stress placed on the joint

20

Describe the positioning of the knee joint capsule in reference to the patella. What does it form?

The capsule ascends superiorly/anteriorly above the patella to form the suprapatellar pouch

21

What lines the inner portion of the knee joint capsule?

synovial membrane

22

What does the synovial membrane exclude from the interior portion of the knee joint?

the cruciate ligaments

23

The cruciate ligaments are ___-synovial and ___-articular

extrasynovial and intra-articular

24

What type of the joint is the proximal tibiofemoral joint?

Plane synovial joint between the Tibia and the Fibular Head

25

Which aspects of the proximal tibiofibular joint are convex and which are concave?

There is a slight convexity on the oval tibial facet and a slight concavity of the fibular head

26

In what direction does the tibial facet at the proximal tibiofemoral joint face?

laterally, posteriorly, and inferiorly

27

Does the proximal or distal tibiofemoral joint have more motion?

proximal

28

What are the 2 glides that can occur at the proximal tibiofemoral joint?

- Superoinferior direction
- Anteroposterior direction

29

The ACL is the primary restraint for which motions?

Anterior translation and medial rotation of the tibia on the femur

30

The PCL is the primary restraint for which motions?

Posterior translation and medial rotation of the tibia on the femur

31

Both the ACL and PCL are the secondary restraints for which motions?

Valgus and varus rotation of the tibia

32

The MCL is the primary restraint for which motions?

Valgus and lateral rotation of the tibia

33

The LCL is the primary restraint for which motions?

Varus and lateral rotation of the tibia

34

Both the MCL and LCL are the secondary restraints for which motions?

anterior and posterior translation of the tibia on the femur

35

The ACL and PCL contain mechanoreceptors, so if there is disruption of these ligaments what happens?

There can be an interruption or elimination of sensory nerve fibers in the joint

36

The ACL's ability to adjust to internal stress influences what 3 things?

- laxity of the joint
- stresses of the joint
- kinematics of the joint

37

Which knee ligament is the strongest?

the PCL

It is twice as strong as the ACL, MCL, and LCL

38

Forcing the ACL more than _% beyond its resting length may result in rupture.

5

39

The PCL provides __-__% of the total restraint to posterior translation of the tibia on the femur

90 - 95%

40

Are the MCL and LCL extra- or intra-articular ligaments

extra-articular ligaments

41

Describe the structure of the MCL

It develops as a thickening of the medial joint capsule and is subdivided into a superficial band and a deep band

42

Describe the superficial band of the MCL

It is a thick, flat band that has a fan-like attachment proximally on the medial femoral condyle and blends with the posteromedial corner of the capsule

43

Describe the deep band of the MCL

It is a continuation of the capsule that blends with the Medial Meniscus

44

Which part of which ligament is the first to be injured when a valgus stress is applied

Superficial band of the MCL

45

Where does the LCL originate and insert at?

It arises from the lateral femoral condyle and runs distally and posteriorly to insert onto the head of the fibula

46

Does the LCL blend with the lateral meniscus?

No it develops independently, and remains completely free from the joint capsule and the lateral meniscus

47

The secondary knee restraints include structures in what aspects of the knee?

the posterolateral and posteromedial corners of the knee

48

What do secondary knee restraints serve to control?

anterior tibial translation relative to the femur

49

What provides dynamic stability to the knee?

Unopposed contraction of the quadriceps complex

50

What does the unopposed contraction of the quadriceps complex increase? And what is it synergistic to?

anterior tibial translation and is synergistic to the PCL

51

What does the unopposed contraction of the hamstrings complex increase? And what is it synergistic to?

posterior tibial translation and is synergistic to the ACL

52

What are 4 other structures that provide support to the knee?

- Popliteus
- Patellar Tendon
- Oblique popliteal ligament
- Fabella

53

What aspect of the menisci are more prone to tear with trauma?

the inner (thinner) regions

54

The outer __% of the lateral meniscus is vascularized

25%

55

The outer __% of the medial meniscus is vascularized

30%

56

What shape is the medial meniscus? What does this result in?

Semilunar (half circle)

Results in a wider separation of its anterior and posterior horns

57

How does the medial meniscus attach to the tibial plateau?

by coronary ligaments

58

What does the MCL also attach to?

to the deeper portion of the MCL and the knee joint capsule

59

What shape is the medial meniscus?

C-shaped

60

The lateral meniscus has an excursion of approximately __ mm, whereas the medial meniscus has an excursion of approximately __ mm.

10

2

61

Which menisci is larger and thicker?

medial

62

What are the 6 functions of the menisci?

- Load Transmission
- Shock Absorption
- Joint Lubrication
- Nutrition
- Secondary Mechanical Stability
- Guiding of Movements

63

List the 8 bursae of the knee

- Superficial Infrapatellar Bursa
- Deep Infrapatellar Bursa
- Prepatellar Bursa
- Tibiofemoral Bursa
- LCL Bursa
- Inferior Subtenindous Bursa (Biceps Femoris Tendon)
- Anserine Bursa
- Semimembranosus Bursa

64

What is a plica?

a remnant of the 3 cavities in the synovial mesenchyme of the developing knee

65

What is the retinacula formed from?

structures in the first and second layers of the knee joint

66

In summary, because the bony surfaces of the knee lend little to inherent stability, what is joint stability reliant on?

The restraints of:
- joint capsule
- ligaments
- menisci
- musculature

67

During flexion of the knee, the femur rolls ____ and glides ______.

posteriorly

anteriorly

68

During extension of the knee, the femur rolls ____ and glides ______.

anteriorly

posteriorly

69

When are the lateral condyle of the femur and the lateral meniscus congruent?

From 30 - 5 degrees of WB knee extension

70

What does the lateral shift of the axis of movement during weight-bearing knee extension produce?

Internal rotation of the femur

71

What movement is the only one to accompany extension in the last 5 degrees of extension? What is this referred to as?

rotation

The “screw home mechanism”

72

During the “screw home mechanism” the tibia ______ rotates and the femur _______ rotates as the knee approaches full extension

externally

internally

73

Knee hyperextension is usually available from _ - _ degrees

0 - 15

74

During knee hyperextension, the femur tilts _____. What does this create?

forward

This creates anterior compression between the femur and the tibia

75

The Q angle is an angle formed by the bisection of what 2 lines?

- ASIS to the center of the patella
- Center of the patella to the tibial tubercle

76

What is the Q angle a measure of?

The tendency of the patella to move laterally when the quadriceps muscles are contracted

77

What is the normal Q angle for males? Females?

- 8–14 degrees for males
- 15–17 degrees for females

78

A Q angle greater than __ degrees is considered abnormal. What is this indicative of?

20

potential displacement of the patella

79

The Patellofemoral Joint Reaction Force is a function of what 2 things?

- Quadriceps and patellar tendon tension
- Angle formed between the quadriceps and patellar tendon

80

During OKC exercises, maximum patellofemoral joint reaction force in the quad/patellar tendon is generated when?

going from 90 degrees to full extension

81

During OKC exercises, the lowest patellofemoral joint reaction force in the quad/patellar tendon is generated when?

at 90 - 40 degrees

82

During CKC exercises, maximum patellofemoral joint reaction force in the quad/patellar tendon is generated when?

at 60 degrees

83

CKC exercises should initially be prescribe at _ - _ degrees and then can progress to _ - _ degrees

0 - 16

0 - 30

84

Describe patellar tracking in the normal knee

the patella glides inferiorly and superiorly during flexion and extension

85

The patella tracks _ - _ cm with respect to the femur during flexion and extension

5 - 7cm

86

The patella moves in a ____ C-shaped curve from 20 to 30 degrees of motion

lateral

87

Between 45 to 15 degrees the lateral curvature produces what 2 things?

- Gradual medial glide of the patella
- Medial tilt of the patella

88

Between 15 to 0 degrees the lateral curvature produces what 2 things?

- Lateral glide of the patella
- Lateral tile of the patella

89

What are 4 abnormal patellar tracking patterns?

- Medial tracking patella
- Lateral tracking patella
- Patella Alta
- Patella Baja

90

What is the Waldron test used to assess?

patellofemoral function

91

A posterior glide of the tibia on the femur increase _____.

flexion

92

An anterior glide of the tibia on the femur increase _____.

extension

93

Describe the 3 grades of a valgus and varus stress test

- Grade I: The joint space opening is within 2mm of the contralateral side
- Grade II: The joint space opens 3-5mm more than the contralateral side in 20 degrees of knee flexion and less than 2mm more than the normal knee in full extension
- Grade III: The joint space opens 5-10mm more than that of the normal knee in 20 degrees of flexion and full extension

94

What 2 tests assess for ACL tear?

- Lachman's Test
- Anterior Drawer Test

95

How is Lachman's test graded?

o 1+ (mild): 5mm or less
o 2+ (moderate): 5-10mm
o 3+ (serious): more than 10mm

96

What 2 tests assess for PCL tear?

- Posterior Sag (Godfrey) Sign
- Posterior Drawer Test

97

What is the pivot shift?

The anterior subluxation of the lateral tibial plateau that occurs when the lower leg is stabilized in (almost) full extension, whereby further flexion produces a palpable spring-like reduction

98

What 2 tests assess for the pivot shift?

- Subluxation Test
- Reduction Test

99

What patient position must patellar stability tests be assessed in?

90 degrees of flexion

100

What does a patellar glide determine?

the amount of lateral deviation of the patella in the frontal plane

101

A 5mm lateral displacement of the patella causes a __% decrease in VMO tension

50%

102

Patella can be passively displaced medially and laterally approximately _ cm, which is 1/_ the width of the patella

1 cm

1/3

103

What is considered abnormal patellar displacement?

more than 1/2 the patella over the medial or lateral aspect

104

What may cause a decrease in the medial glide of the patella?

IT Band and/or lateral retinaculum tightness

105

A slight ____ tilt of the patella is normal.

lateral

106

What does a medial tilt result from?

a tight lateral retinaculum

107

If the inferior pole of the patella is sitting lateral to the long axis of the femur, the patient has an _______ rotated patella

externally

108

If the inferior pole of the patella is sitting medial to the long axis of the femur, the patient has an _______ rotated patella

internally

109

What are the 6 meniscal tear tests?

- McMurray's Test
- Apley's Test
- Anderson Mediolateral Grind Test
- Bounce Home Test
- Figure-4 Test
- Payr Sign

110

When performing McMurray's test how does the clinician test the integrity of the medial meniscus?

ER the tibia while slowly extending the knee

111

When performing McMurray's test how does the clinician test the integrity of the lateral meniscus?

ER the tibia while slowly extending the knee

112

What is indicative of a positive test for a rotation sprain of the soft tissue when performing Apley's test?

Pain upon distraction and IR and ER rotation of the tibia

113

What is indicative of a positive test for a meniscal tear when performing Apley's test?

Pain upon compression while IR and IR the tibia

114

When performing the Anderson mediolateral grind test a ____ stress should be applied while the knee is flexed and a ____ stress should be applied while the knee is flexed

valgus

varus

115

Which meniscus test assess for a lateral meniscus tear? Medial meniscus tear?

Figure-4 Test

Payr Sign

116

What are the 4 characteristics of plical irritation?

- Anterior pain in the knee
- Painful clicking
- Giving way
- Catching

117

What are the 2 tests that assess for patellar chondromalacia?

- Zohler’s Sign
- Clarke’s Test