Anatomy - Elbow Joint

Question 1

Elbow joint

Answer 1

• 4 articular surfaces
• 3 bones
• 4 ligaments
• hinge joint (humeroradial joint + humeroulna)
• pivot joint (proximal radioulnar)

Capitulum of humerus + head of radius
Trochlea of humerus + trochlea notch of ulna

Question 2

3 Bones

Answer 2

Humerus
Radius (lateral)
Ulna (medial)

Question 3

4 Ligaments

Answer 3

1. Joint capsule
2. MCL (3 bands)
   - anterior band (medial humeral epicondyle to medial coronoid process of ulna)
   - posterior band (medial humeral epicondyle to olecranon)
   - transverse band (connecting two bands on ulnar)
3. LCL (tip of lateral humeral epicondyle to annular ligament)
4. Annular ligament (radial head)

Question 4

8 Muscles attachment at lateral humeral epicondyle

Answer 4

Extensors of elbow joint

1. Supinator
2. ECRB
3. ECRL
4. EDM
5. ECU
6. ED
7. Brachioradialis
8. Anconeus

++along lateral shaft
APL
EPL
EI

Question 5

5 Muscles attachment at medial humeral epicondyle

Answer 5

Flexors
Posteriorly
1. FDS
2. FCU

Anteriorly

3. FCR
4. PL
5. PT

Question 6

Capsular attachment

Answer 6

Anteriorly: Margin of radial fossa and coronoid fossa of humerus + Margin of coronoid fossa of ulnar + Annular ligament of radius

Posteriorly: Margin of olecranon fossa of humerus + olceranon process of ulna + annular ligament of radius

Question 7

Movement of the elbow joint

Answer 7

1. Flexion

2. Extension

Question 7

4 flexors of elbow joint

Answer 7

1. Brachialis
2. Biceps brachii
3. Brachioradialis
4. Pronator teres

Question 8

2 extensors of elbow joint

Answer 8

1. Triceps

2. Anconeus

Question 9

Angle between long axis of arm and forearm on full extension?

Answer 9

“Known as carrying angle”

• 170 degree in male
• 167 degree in female

*angle dissapears in full flexion

Question 10

Structures passes anterior to elbow joint

Answer 10

2 tendons
1 nerve
1 artery

brachialis
biceps brachii
median nerve
brachial artery

Question 11

Structures passes posterior to elbow joint

Answer 11

Triceps tendon

Question 12

Structures passes medial to elbow joint

Answer 12

Ulnar nerve

Question 13

Structures passes lateral to elbow joint

Answer 13

1. Common extensors tendon

2. Supinator

Question 14

Muscles attachment at medial proximal ulna

Answer 14

1. FDP

Question 15

Isosceles triangle formed by _____ during elbow flexion

Answer 15

1. Medial humeral epicondyle
2. Lateral humeral epicondyle
3. Olecranon prominence

*all these three points become in-line on elbow extension