Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

knee > muscles and movements > Flashcards

muscles and movements Flashcards

1
Q

knee locking mechanism (standing knee extension)

A
  • knee joint is ‘locked’ in closed pack position
  • joint surfaces more congruent
  • COG anterior to knee joint maintaining extension
  • femoral medial rotation and extension tightens ligaments
  • popliteus initiates ‘unlocking’ mechanism by laterally rotating femur on fixed tibia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

knee locking mechanism (locking into closed packed position extension, sitting to standing)

A

Femoral condyles roll anteriorly over tibial condyles
Femoral condyles glide posteriorly over tibial condyles (stops femoral condyles rolling off tibial condyles)
Shorter lateral femoral condyle movement stops first
Femur medially rotates (spins) around fixed lateral condyle to complete the movement.

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

Knee (Un)Locking MechanismClosed Kinetic Chain
Unlocking knee joint into Open Packed Position (Flexion)
Standing to Sitting

A

Femur rotates (spins) laterally on the tibia
Femoral condyles roll posteriorly on the tibial condyles (relatively fixed)
Femoral condyles glide anteriorly on the tibial condyles. (This stops femoral condyles from rolling off the tibial condyles.)

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

quadriceps muscles

A

Rectus Femoris
Vastus Medialis
Vastus Intermedius
Vastus Lateralis

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

knee flexors

A 
-hamstrings
  biceps femoris
  semitendinosus
  semimembranosus
-sartorius
-popliteus
-gastrocnemius
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

biceps femoris

A 
Origin:2 heads
Long head; inferomedial part of upper area ischial tuberosity
Short head; lateral lip linea aspera (Lateral supracondylar ridge)
Insertion
Head of fibula
Action at the Knee
Flexion and ER
Nerve Supply
Sciatic Nerve L5-S2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

semitendinosus

A 
Origin
Inferomedial part upper area ischial tuberosity
Insertion
Medial surface proximal tibia
Action at the Knee
Flexion and IR
Nerve Supply
Sciatic Nerve L5-S2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

semimembranosus

A 
Origin
Superolateral impression ischial tuberosity
Insertion
Groove and adjacent bone medial and posterior surface medial tibial condyle
Action at the Knee
Flexion and IR
Nerve Supply
Sciatic Nerve L5-S2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

hamstrings action

A

Actions:
All 3 extend the hip and flex the knee joint
BF laterally rotates the hip and knee joints
ST and SM medially rotate the hip and knee joints
Nerve supply
Sciatic nerve
L5-S2(S3-LongHeadBF)

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

sartorius

A 
Origin
Anterior superior iliac spine
Insertion
Anterior surface of tibia just inferomedial to tibial tuberosity
Actions at the Knee
Medial rotation, flexion knee
Nerve supply
Femoral nerve L2,3
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

popliteus

A

Small, flat, deep, posterior muscle
Part of floor of popliteal fossa
Origin - Lateral femoral condyle
Insertion - Proximal surface of posterior tibia
Action - Unlocks the extended knee by laterally rotating femur on fixed tibia, rotates knee medially, flexes knee
Nerve supply - Tibial nerve L4,5,S1

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

planters

A

Origin
Lateral supracondylar line above lateral head of gastrocnemius
Insertion
Medial border of TA and post. surface of calcaneus
Action
Weak knee flexor and plantar flexor of foot
Nerve supply
Tibial L4,5,S1.

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

gastrocnemius

A

Origin - 2 heads - Medial and lateral heads from medial and lateral femoral condyles
Insertion - Achilles tendon into postero-superior calcaneus
Actions - knee flexion and ankle plantarflexion
Nerve supply - Tibial nerve -S1,2

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

knee extensors

A 
Quadriceps:
Rectus Femoris
Vastus Intermedius
Vastus Lateralis
Vastus Medialis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

rectus femoris

A 
Actions
2 joint muscle
Extends knee and flexes hip
Nerve supply
Femoral nerve L2,3,4
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

vastus intermedius

A

Origin
Femur-upper 2/3rds anterior and lateral surfaces
Insertion
Quadriceps tendon (deep part) and lateral border of patella

17
Q

vastus medialis

A

Origins
Femur-medial part of inter-trochanteric line,pectineal line, medial lip of linea aspera, medial supracondylar line
Insertion
Quadriceps tendon and medial border of patella

18
Q

vastus lateralis

A

Origin
Lateral part of intertrochanteric line, lateral margin of greater trochanter, lateral margin gluteal tuberosity, lateral lip linea aspera
Insertion
Quadriceps tendon and lateral margin of patella

19
Q

knee medial rotators (of tibia on femur)

A

Semitendinosus
Semimembranosus
Sartorius
Popliteus

20
Q

knee lateral rotators (of tibia on femur)

A

biceps femoris

21
Q

biceps femoris

A 
Origin:2 heads
Long head; inferomedial part of upper area ischial tuberosity
Short head; lateral lip linea aspera (Lateral supracondylar ridge)
Insertion
Head of fibula
Action at the Knee
Flexion and ER
Nerve Supply
Sciatic Nerve L5-S2
22
Q

vastus medialis controversy

A

VM - historically thought to be the only muscle to produce the final 15 degrees of knee extension - therefore patients were given specific exercises to train VM muscle in that range!
Evidence now that VM is not specifically responsible for the final 15 degrees of knee extension
VM acts throughout the range of knee extension with or without external resistance.

23
Q

Knee Joint Movements, Range, and Limiting Factors

A 
Flexion - +/-135°
Limited by soft tissue apposition, patellar tendon, PCL
Extension 0° (Hyperextension 0-5°)
Posterior capsule, ACL, PCL, MCL, LCL, Oblique popliteal ligament), tension in antagonists
Rotations (in 90° flexion)
Medial; 20-30°
Lateral; 30-40° 
Limited by tension in antagonists
24
Q

Popliteal Fossa Borders

A 
Borders (Laterally)
Biceps femoris
Lateral head Gastrocnemius
Borders (Medially)
Semimembranosus
Semitendinosus
Medial head Gastrocnemius
Floor
Popliteal surface of femur
Roof
Fascia and skin
25
Q

Popliteal Fossa Contents

A

Contents
Popliteal artery and vein
Common peroneal and tibial nerves
Lymph nodes and fat

26
Q

Tensor Fasciae Latae (TFL)

A 
Origin
Anterior superior iliac spine (and outer iliac crest to iliac tubercle)
Insertion
Anterior surface of tibia just inferolateral to tibial tuberosity (Gerdy’s tubercle)
Actions at the Knee
Stabilises knee laterally
Nerve supply
Femoral L2,3,4

knee (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions