Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biomechanics > Knee > Flashcards

Knee Flashcards

(88 cards)

Start Studying
0
Q

What bones are involved in the knee joint?

A

Femur, tibia, patella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

What type of joint is the knee joint?

A

Modified ginglymus joint (hinge joint)

Provides flexion and extension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Joints of the knee

A

Tibiofemoral joint

Patellofemoral joint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Tibiofemoral joint

A

Proximal concave tibia articulated with the convex distal femur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What makes the tibia concave for the tibiofemoral joint?

A

Meniscus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Patellofemoral joint

A

articulation of posterior surface of the surface of the patella and the trochlear surface of the anterior femur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the Q Angle?

A

Alignment at patellofemoral joint formed between a line connecting the ASIS to the midpoint of the patella and a line to the tibial tuberosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a normal Q-angle?

A

185-190 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What can a smaller than normal Q-angle cause?

A

increased medial knee pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What can a larger Q-angle cause?

A

Increase lateral knee pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Genu Valgum

A

(knock kneed) q-angle greater than 190….5-10 is normal and normally higher on females
increase compression in lateral compartment of the knee

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Genu Varum

A

(bow legged) knee angle less than 170…less common.
Can be predisposed by: coxa vara-angle less than 125/weak hip abductors
increase compression in medial compartment of knee

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Genu Recurvum

A

(hyperextension) extension beyond +10 of neutral
area of condyles in contact during end range extension is decreased resulting in increased compressive forces secondary to smaller area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Proximal Tibioiblar

A

Articulation of the proximal tibial and fibula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are some functions of the proximal tibiofibular joint?

A

Dissipation of torsional stresses applied at ankle
Dissipation of lateral tibial bending movements
Tensile weight bearing (most joints have compressive forces)
movement occurs with movement of ankle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Does proximal tibiofibular joint move the same or opposite direction of the distal tibiofibular joint?

A

Opposite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of joint is the tibiofemoral joint?

A

Double condyloid synovial joint

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Tibiofemoral Joint

A 
3 degrees of freedom
convex femur articulates with concave tibia
2 perspectives (tibia on femur-open/femur on tibia-closed)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Arthrokinematics of Tibiofmoral Joint

A

Open Chain-Roll and Glide occur together

Closed Chain-Roll and Glide opposite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Tibia on Femur Arthrokinematics

A

(concave on convex)
Extension: Anterior Roll and Glide
Flexion: Posterior Roll and Glide
IR/ER=spin?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Femur on Tibia Arthrokinematics

A

(convex on concave)
Extension: Anterior Roll and Posterior Glide
Flexion: Posterior Roll and Anterior Glide
IR/ER: Spin?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Tibiofemoral Closed

A

Full Extension w/ ER

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Tibiofemoral Open

A

25-30 Knee Flexion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Tibiofemoral Capsular Patter

A

Flexion > Extension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Screw Home Mechanism
Occurs in the final 20-30 degrees of knee extension If the foot is planted on the floor with knee flexed, extension of the knee causes: -ACL to become tight which restrits movement of lateral femoral condyle -Medial condyle isnt so keeps moving -causes tibial ER (Femoral IR) -This "locks" the knee at full extension
25
what happens if this lock knee does not occur?
Other joints compensate, shortened flexors and lengthened extensors
26
What muscle unlocks the knee?
Popliteus - causes the tibia to medially rotate during flexion of the knee
27
Patellofemoral Joint
Patella slides along fixed intercondylar groove in open chain Intercondylar groove slides along fixed patella in closed chain most commonly referred at open chain
28
What is a function of the patellofemoral joint?
increases the angle of insertion for quads and increases the torque producing capacity for quads
29
Gliding motions of patellofemoral joint
``` flexion and extension (superior and inferior glides) medial and lateral glides medial and lateral tilts medial and lateral rotation anterior and posterior tilts ```
30
Patella Alta
High Riding Patella | Increased length of patella tendon and higher chance of subluxation
31
Patella Baja
Low riding patella | shortened patella tendon...increases compression can lead to arthritis
32
Contraction of quads causes a ______ compressive force on the patella.
increased
33
What type of joint is the proximal tibiofibular joint?
Plane synovial joint
34
Proximal Tibiofibular Joint
``` Proximal fibular slightly convex articulating with the slightly concave proximal tibia 3 degrees of freedom -anterior/posterior -superior/inferior -rotation ```
35
Tibiofibular joints open positions
0 degrees plantar flexion
36
Tibiofibular joints closed position
full ankle dorsiflxion
37
Tibiofibular joints capsular pattern
pain with biceps femoris muscle contraction
38
Lateral Patellar Tracking
*Tight lateral bands ITB Bowstringing (more common in runners) Lateral patellar retinacular fibers
39
Medial Patellar Tracking
*tight medial fibers/muscle activity VMO Raised lateral facet Medial Patellar retinacular fibers
40
External Force Patellar Tracking
Valgus force (increased genu valgum-to compensate) ER of femur IR of Tibia
41
What are the effects of patellar tracking?
increased tension at Quadricep Tendon and Patellar Tendon | increases bowstringing force
42
Where is the Anterior Cruciate Ligament (ACL) located?
Attaches to the anterior tibia and runs in a posterior, lateral, and proximal direction attaching to lateral femoral condyle.
43
What are the bands of the ACL?
Anteromedial Intermedial Posterolateral
44
What are the functions of the ACL?
1. most effective in extension 2. resist excessive tibial anterior slide/translation 3. resist excessive femoral posterior slide/translation 4. Resist excessive axial rotation, varus and valgus 5. resists knee extension (prevent hyperextension)
45
Which bands of the ACL are tight/slack in knee extension?
posterolateral band tight (control rotation at tibia) and anteromedial band is slack
46
Which bands of the ACL are tight/slack in knee flexion?
Posterolateral band is slack | Anteromedial band is tight
47
How is the ACL injured?
Large valgus force with foot planted Large axial rotation force applied with foot planed Combination of the previous two Severe hyperextension
48
What is the Terrible Triad
ACL, MCL, Medial Meniscus
49
Can cruciate ligaments repair on their own?
No
50
Where is the Posterior Cruciate Ligament (PCL) located?
Attaches to the posterior tibia and runs in a proximal, medial and anterior direction attaching to the medial femoral condyle
51
What is the function of the PCL?
Most effective in flexion Resist excessive tibial posterior slide/translation Resist excessive femoral anterior slide/translation Resist excessive axial rotation, varus, and valgus forces
52
How is the PCL injured?
Falling on fully flexed knee with proximal tibia striking 1st Force posterior translation of tibia Worse with increasing flexion Rotation, varus, and/or valgus force applied w/ foot planted Severe hyperextension w/ gapping to posterior side
53
Where is the Medial Collateral Ligament (MCL) located?
Superficial Portion - Attaches proximally to the medial femoral epicondyle and distally and shaft of the tibia and tibia condyle Deep portion- attaches to medial meniscus and blends with joint capsule
54
What is the function of the MCL?
Resists valgus force, knee extension, reinforce medial capsule and prevent ER of leg with knee extended
55
How is the MCL injured?
Valgus force with foot planted or severe hyperextension | - most commonly torn with ACL
56
Where is the Lateral Collateral Ligament (LCL) located?
Runs from the lateral epicondyle of the femur to the head of the fibula
57
Does the MCL or LCL attach to adjacent meniscus?
Only the MCl
58
What is the function of the LCL?
``` Resist varus force Resist knee extension Prevent ER of the leg (with knee extension) Reinforce lateral capsule Reinforce posterior-lateral capsule ```
59
How is the LCL injured?
Varus force with foot planted | Severe hyperextension
60
What structures reinforce the capsule of the knee anteriorly?
``` Connective tissue (patellar tendon and retinacular fibers) Muscular - tendinous (quads) ```
61
What structures reinforce the capsule of the knee laterally?
``` Connective tissue (LCL, lateral retinaculum, ITB) Muscular-tendinous (biceps femoris, popliteus, gastroc) ```
62
What structures reinforce the capsule of the knee posteriorly?
``` Connective tissue (oblique popliteal ligament, arcuate ligament) Muscular-tendinous (gastrocs, hamstrings) ```
63
What structures reinforce the capsule of the knee posterior-lateral?
Arcuate complex, LCL | Popliteus
64
What structures reinforce the capsule of the knee medially?
Retinaculum, MCL, posterior-medial capsular, posterior oblique ligament Pes anserine
65
What muscles have an insertion point that make the pes anserine?
Semitendinosus, gracilis, sartorius
66
What is the most common orthopedic repair?
Meniscus
67
What are the meniscus?
Fibrocartilaginous discs | Located directly between the femoral condyles and the tibial plateau
68
Why does the meniscus have limited healing potential?
the meniscus only has a peripheral blood supply so it cannot heal on its own
69
What is the function of the meniscus?
Deepen surface of the tibia makes a concavity atop the tibial plateauj Shock absorbers (compression provides nutrients?)
70
Which meniscus is more likely to be injured?
Medial by 2X
71
What are characteristics of the medial meniscus?
larger and more C-shaped anterior and posterior horns Firms attachment to the MCL and medial capsule
72
Why is the medial meniscus more frequently injured?
Due to firm attachment to the tibia and decreased mobility makes it more prone to injury
73
What are characteristics of the lateral meniscus?
More circular shape, loosely attached to tibia and absorbs more of the stress for less inury
74
What soft tissues attach to the meniscus?
MCL and semimembranosus to Medial | Poplieus to Lateral
75
How does the menisci move during knee extension?
menisci move anteriorly with tibia
76
How does the menisci move during knee flexion?
menisci move posterior with tibia
77
How are the menisci injured?
axial rotation and valgus force most common
78
50 percent of all ______ tears associates with meniscal injury.
ACL
79
Injury can be associated with early onset ________
Osteoarthritis......less cartilage = less shock absorption
80
What is the function of bursae in the knee?
Reduces friction between the moving structures
81
Infrapatellar Fat Pad
Between the patellar tendon and tibia Very sensitive Helps reduce friction in the knee
82
What muscles extend the knee?
``` Quads -rectus femoris -vastus medialis -vastus lateralis -vastus imtermedius Articularis genu ```
83
What muscles flex the knee?
``` Hamstrings -semitendinosus -semimembranosus -bieps femoris (long and short head) Sartorius Gracilis Popliteus Gastrocnemius Plantaris ```
84
What knee flexor is not biarticular?
Popliteus
85
What is the length tension relationship?
Muscles at full contraction or extension lose contractile capabilities
86
Active insufficieny
Extreme shortened muscle results in decreased motor recruitment (must shorten over both joints)
87
Passive insufficiency
Tightened/lengthened muscles causes decreased muscle contraction

Biomechanics (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions