Second Midterm - Week 6 knee Flashcards
(110 cards)
1
Q
What three joints make up the knee complex?
A
- tibiofemoral joint (posterior)
- tibiofibular joint
- patellofemoral joint (anterior)
2
Q
The femoral condyles are separated by a fossa and are egg shaped. It has a larger (anterior/posterior) radius and a smaller (anterior/posterior) radius
A
Larger anterior radius
Small posterior radius
3
Q
The femoral condyles have a divergent axes of motion which creates conjoint rotation. What is the screw home mechanism?
A
The tibiofemoral joint rotates around the lateral condyles
(Tibia externally rotates and femur internally rotates to lock the knee into extension and visa versa. This maximally stabilizes the knee)
4
Q
Which femoral condyle has a larger and longer articular surface?
A
Medial condyle
5
Q
Which femoral condyle has a smaller epicondyle?
A
Lateral condyle
6
Q
Which femoral condyle is more obliquely orientated?
A
Medial condyle
7
Q
Which femoral condyle extends more distally?
A
Medial condyle
8
Q
When the knees are anatomically touching but the ankles are not (knock-knees), this is called genu _____
A
Valgum
9
Q
When the knees are anatomically distant but the ankles are touching (bow-legged), this is called genu ______
A
Varum
10
Q
A normal medial twist of the knee is _____ degrees
A
10-20
11
Q
Anteverted femur is _____ degrees. This correlates with genu ______ and a (medial/lateral) orientation
A
> 20
Genu valgum
Medial orientation
12
Q
Retroverted femur is _____ degrees. This correlates with genu ______ and a (medial/lateral) orientation
A
<10
Genu varum
Lateral orientation
13
Q
The tibial condyles are the flat superior surface. The tibial spine provide attachment points for WHAT THREE STRUCTURES and what is their FUNCTION
A
- ACL/PCL and meniscus
- help stabilize the knee
14
Q
Which tibial condyle is larger?
A
Medial tibial condyle
15
Q
T/F the tibial condyles are concave
A
F they are flat
16
Q
The medial and lateral articular surfaces of tibial condyles are separated by ________
A
Intercondylar eminence
17
Q
What are the fibrocartilage shock absorbers that sit on the surface of tibial condyles and what are their functions (4)
A
- medial and lateral menisci
- deepen the articular surface to increase stability
- Makes a flexible socket to condyles
- Accommodate slide and decrease shear stress
- Reduce wear and tear
18
Q
The slight posterior ngulation of the condyles helps to ________
A
Prevent hyperextension
19
Q
External tibial torsion may be responsible for foot _____
A
Foot flare
20
Q
What type of cartilage lines the patellar surface of the femur?
A
Hyaline cartilage
21
Q
T/F the patellar surface of the femur is anterior to the condyles
A
T
22
Q
On the patellar surface of the femur the lateral facet is (smaller/larger) and the lateral lip is (shorter/taller) than the medial?
A
Larger
Taller
23
Q
What is the main function of the patella?
A
Increase the angular pull of the quads
24
Q
The lateral facet on the patella is (smaller/larger) than the medial?
A
Larger
25
The patella has the (thinnest/thickest) cartilage in the body?
Thickest
26
Patella Baja is when the patellofemoral ratio is _____
<0.8 and the patella is too distal to the knee
27
Patella Alta is when the patellofemoral ratio is ______
>1.2 and the patella is too proximal to the knee
28
What makes up the patellofemoral ratio X:Y or X/Y?
```
X = length of the infrapatellar tendon
Y = S-I diameter of patella
```
29
During flexion, the patella glides _________ and __________ in the patellar sulcus.
Inferior and posterior
30
How much contact between the patella and femur exists when the knee is in flexion at
- 0 degrees
- 30 degrees
- 60-90 degrees
- 135 degrees
- no contact
- Inferior pole of patella contacting superior part of condyles
- max contact
- superior pole of patella contacting inferior aspect of condyles. And the odd medial facet contact
31
At what degree of flexion is the max contact between the patella and femur?
60-90 degrees
32
At what degree of flexion is the odd medial facet in contact with the femur
135
33
At what degree of flexion is the inferior pole of the patella in contact with the femur? What about the superior pole?
30
| 135
34
What two intersecting lines create the patellofemoral Q-angle?
- ASIS -> center of patella
| - center of patella -> tibial tuberosity
35
What is the normal range of patellofemoral Q-angle? For women? For men?
5-15
Women = 10-12
Men = 8-10
36
The patellofemoral Q-angle represents the pull of the ______
Quads
37
Genu varus (increases/decreases) the Q angle? Genu Valgum (increases/ decreases) the Q angle?
Decreases
| Increases
38
The patella is less stable when
1. knee is (flexed/extended)
2. VMO is (weak/strong)
3. Genu _______
4. vastus lateralis is (too loose/too tight)
5. patella is (too small/too large)
6. patellar facet angle is (too flat/too angled)
7. (small/large) lateral lip or (deep/shallow) groove
8. patella (baja/alta)
9. (internally/externally) rotated tibia
10. (decreased/increased) foot flare
11. excessive foot (pronation/supination)
1. Knee EXTENDED
2. VMO WEAK
3. Genu VALGUM
4. VL too TIGHT
5. Patella too SMALL
6. Patellar facet angle too FLAT
7. SMALL lateral lip or SHALLOW groove
8. Patella ALTA
9. EXTERNALLY rotated tibia
10. INCREASED foot flare
11. Excessive foot PRONATION
39
What type of cartilage is the meniscus?
Fibrocartilagenous
40
A partial meniscectomy creates ______% increase in wear and tear. A full meniscectomy creates _____%
50-60
| 100+
41
The shape of the medial menisci is (C/O)? The lateral menisci is (C/O) shaped?
```
Medial = C
Lateral = O
```
42
Which menisci is thinner and more fixed? Which is stronger and more mobile?
Medial
| Lateral
43
Which menisci is more often injured?
Medial
44
The lateral menisci makes up ____% of menisci tears?
25
45
The MCL and semimbranosus tendon attach to the ____ menisci
Medial
46
The popliteus attached to the ____ meniscus
Lateral
47
Which ligament arises form the posterior horn of the lateral meniscus travels anterior to the PCL and attaches to the lateral surface of the medial condyle of the femur?
Anterior meniscofemoral ligament (Humphrey)
*The posterior meniscofemoral ligament (Wrisberg) travels posterior to the PCL
48
During flexion, the menisci slide (anterior, posterior). Which moves more, the lateral or medial?
Posterior
| Lateral moves more
49
During flexion, there is more focal weight on the (anterior/posterior) horns of the menisci ?
Posterior
50
Deep squats increase stress on the (anterior/posterior) horns of the menisci?
Posterior
51
During flexion, synovial fluid is squeezed (anterior, posterior) in the menisci?
Posterior
52
During extension the menisci slide (anterior/posterior)? Which moves more, the lateral or medial
Anterior
| Lateral moves more
53
During extension the (medial/lateral) menisci deforms more?
He medial deforms more
| **attached to the MCL
54
At full extension, there is (more/less) total pressure on the menisci and (more/less) focal pressure?
More total
| Less focal
55
During extension, the synovial fluid in the menisci is pushed (anterior/posterior)
Anterior
56
T/F menisci rotate with the femur
T
*abnormal motion leads to tears
57
During tibial internal rotation, the medial meniscus rotates (anterior/posterior) which increases the pressure.
The lateral meniscus moves (anterior/posterior)
Anterior
| Posterior
58
During tibial external rotation, the medial meniscus rotates (anterior/posterior)
The lateral meniscus moves (anterior/posterior) which increases the pressure
Anterior
| Posterior
59
Genu varus pinches he (medial/lateral) meniscus & tractions the (medial/lateral) meniscus through coronary ligaments
Medial
| Lateral
60
Genu valgum pinches he (medial/lateral) meniscus & tractions the (medial/lateral) meniscus through coronary ligaments
Lateral
| Medial (also through the collateral ligament)
61
Which part of the menisci has a blood supply?
Outer 1/3 in young and healthy
62
Are the menisci innervated?
Yes for pain and proprioception
63
What affect does aging have on the menisci? (3)
- decreased vascularization
- increased wear and tear
- increased friability
64
Where does the MCL attach? It resists (valgus/varus) stress
Medial femoral condyle & medial tibial condyle
*hence aka tibial collateral ligament
Valgus
65
How is the MCL sprained?
Direct blow to the lateral side of the knee
| External rotation force (twisting)
66
Where does the LCL attach? It resists (valgus/varus) stress?
Lateral femoral epicondyle & fibular head
*hence aka fibular collateral ligament
Varus
67
How is the LCL sprained?
- Direct blow to the medial side of the knee
| - hyper extension
68
Medial rotation (increases/decreases) tension on collaterals? Lateral rotation?
Decreases
| Increases
69
The ACL and PCL are (intra/extra)capsular, (intra/extra)synovial and support vessels for nutrients
Intracapsular
| Extrasynovial
70
Where does the ACL attack?
Anterior tibial plateau and tibial spine & the medial aspect of the lateral femoral condyle
71
The ACL is (larger/smaller) than the PCL
Smaller
72
The ACL is always tense because the (anterior/posterior) band is taut in flexion and the (anterior/posterior) band is taut in extension
Anterior
| Posterior
73
T/F the ACL is not vascularized?
False. It is highly vascularized and the knee will fill with blood if it is torn
74
The ACL resists (anterior/posterior) translation of the tibia
Anterior
75
What is the most common serious ligament injury to the knee?
ACL
76
___ of all knee hemiarthrosis involve the ACL
3/4
77
What is the test for ACL
Anterior drawer test: anterior tibial translation joint play (anterior glide)
78
Where does the PCL attach?
Posterior tibial plateau and posterior tibial spine & lateral aspect of the medial femoral condyle
79
The PCL is ____________ in relation to the ACL
Posteromedial
80
The PCL is __ times as strong as the ACL
2x
81
The PCL is always tense but is lest tense at ____ degrees of flexion
25-40
*it also has two parts like the ACL
82
Which crucial ligament is lest likely to require surgery?
PCL
83
The PCL resists (anterior/posterior) translation of the tibia
Posterior
84
How can you see if a PCL is torn? (2)
- posterior sag sign
| - posterior drawer test: posterior tibial translation join play (posterior glide)
85
The cruciates twist around each other in (internal/external) rotation of the femur?
Internal
*helps lock out with screw home mechanisms during extension
86
Which cruciate is weaker and more likely to tear due to internal rotation?
ACL
87
The cruciates untwist during (internal/external) rotation of the femur?
External
| *help to unlock during takeoff
88
The IT blends with the __________ and attaches to ______
Lateral retinaculum
| Gerdy’s tubercle
89
A tight IT band rubs on the lateral femoral condyle and pulls on the ______. This is called ______
Patella
| ITB syndrome
90
The posteriormedial capsular complex consist of what 3 things?
- posterior part of MCL
- semimebranosus tendon
- oblique popliteal ligaments
91
The posteriomedial capsular complex resists:
- hyper (extension/flexion)
- (anterior/posterior) translation
- (varus/valgus) stress
- extreme rotation: lateral (>/
- hyperextension
- anterior translation
- valgus stress
- extreme rotation (lateral >medial)
92
The posterolateral capsular complex consists of? (6)
- LCL
- poplitiofibular ligament (PFL)
- arcuate ligament
- biceps femoris tendon
- popliteus
- ITB
93
The Posterolateral capsular complex resists:
- hyper (extension/flexion)
- (anterior/posterior) translation
- (varus/valgus) stress
- extreme rotation: lateral (>/
- hyper extension
- anterior translation
- varus stress
- extreme rotation: medial > lateral
94
What does the PFL stand for? It _____ during flexion and helps provide support to the knee
Poplitiofibular ligament
| - tenses
95
What 4 bursa/cysts is the joint cavity connected to?
- Suprapatellar bursa
- popliteal bursa
- bakers cyst (aka popliteal cyst)
- gastrocnemius bursa
96
What 4 bursa are not connected to the joint cavity?
- pre-patellar
- infrapatellar
- pes anserine
- ITB
97
What ”ligaments” are actually extensions of he quadriceps tendon?
Medial and lateral retinaculum
98
Valgus sprain and patellar dislocations tear the (medial/ lateral) retinaculum?
Medial
99
Weak or stretched (medial/lateral) retinaculum OR tight (medial/lateral) retinaculum can cause patellar instability
Medial
| Lateral
100
What is the synovial plica?
Remnant embryonic sac
| *most are small and asymptomatic
101
Which one has more co-contracted, closed or pen chain?
Closed
102
Increased velocity = (increased/decreased) co-contraction of antagonist
Increased
103
What is the balance between quads and hamstrings ratio?
~60:40
104
VMO is most important to ______ stability
Patellar
105
Muscle contraction is _____ stability
Dynamic
| * they are secondary stabilizers
106
Walking on a stable surface produces _____ BW on quad tension.
- Jogging = ?BW
- sprinting = ?BW
- jumping = ?BW
1x
- 5x
- ~7x
- >10x
107
The patella increases extensor leverage ___% when knee is flexed 90-120
13
108
The patella increase extensor leverage ___% when the knee is flexed 0-5
31
109
What is PERCENTAGE of BW on quadriceps force during squats at the following degrees:
- 5
- 15
- 30
- 45
- 75
- 30% of BW
- 100% of BW
- 200% of BW
- 300% of BW
- 500% of BW
110
What is the compression force on the patella during
1. walking?
2. Jogging?
3. Stair climbing?
4. Down a stair?
5. 90 degree squat?
6. Knee extension?
7. Jumping?
1. 0.5x BW
2. 4x BW
3. 2.4x BW
4. 3.5x BW
5. 7.5x BW
6. 8x BW
7. >10x BW
