Elbow joint complex

Question 1

Function of the elbow joint complex

Answer 1

Allows upper limb to shorten and lengthen

Question 2

What type of joint is the elbow joint

Answer 2

Synovial hinge composed of 2 inter related joints - humeroulnar and humeroradial joint

Question 3

Describe to 2 joints which the elbow joint is composed of

Answer 3

Humeroulnar joint - trochlea of humerus fits into trochlear notch of ulna

Humeroradial joint - head of radius articulates with capitulum of humerus

Question 4

Medial lateral epicondyles

Answer 4

Rounded projection of either side

Question 5

trochlea and capitulum articular surfaces

Answer 5

Trochlea (medial) - pulley shaped groove, articulates with the trochlear notch of the ulna
Capitulum (lateral) - small rounded process on the anterior inferior surface that articulates with the had of the radius

Question 6

Coronoid fossa (anterior)

Answer 6

receives coronoid process of ulna during elbow flexion

Question 7

Olecrannon fossa (posteror)

Answer 7

receives olecranon process of ulna during elbow extension

Question 8

Body landmarks of proximal ulna

Answer 8

Lies medial to the radius and is the longer of the 2 bones
Head of the radius sits ito the radial notch on the ulna
Has a hook like projection called the trochlear notch which articulates with the trochlea of the humerus
Olecranon process posteriorly
Coroniod process anteriorly

Question 9

Body landmarks of the proximal radius

Answer 9

lies lateral to the ulna
disc shaped head of the radius articulates with the capitulum and sits into the radial notch of the ulna
Radial tuberosity is a raised rough area on anterior and medial side

Question 10

What is the carrying angle?

Answer 10

A lateral values angle between the upper arm and forearm
Trochlea of the humerus protects more distally and anteriorly than the lateral edge
This L shaped angle allows the elbow to fit into the depression above the iliac crest and aids in carrying heavy loads

Question 11

State the usual carrying angles in males and females

Answer 11

Using 5 degrees in males

10 - 15 degrees in females

Question 12

Ulnar collateral ligament

Answer 12

Very strong, starts at medial epicondyle of humerus, fans out in triangular shape
Maintains medial joint stability

Question 13

Radial collateral ligament

Answer 13

Starts at lateral epicondyle of humerus and attaches to annual ligament
Provides lateral stability

Question 14

Annular ligament

Answer 14

Ancircles 4/5s of the radial head
Attaches to the anterior and posterior margins of the radial notch
Upper fibres strengthened by the radial collateral ligament
Ensures stability of radial head by holding it into the radial notch
Allows head to rotate

Question 15

Interosseous membrane

Answer 15

Strong fibrous sheet which connects inner borders of ulna and radius from proximal to distal end
Helps absorb forces transmitted from the hands
Prevents displacement of the radius from the ulna
Provides a large source area for muscle attachments

Question 16

Interosseous membrane

Answer 16

Strong fibrous sheet which connects inner borders of uni and radius from proximal to distal end
Helps to absorb forces transmitted from the hands
Prevents displacement of the radius from the ulna

Question 17

Elbow - pronation

Answer 17

Radius moves medially

Ends up crossing the ulna

Question 18

Supination

Answer 18

Radius moves laterally Ends up parallel to the ulna