Lecture 8 -Elbow Joint and Forearm

Question 1

Elbow Joint

Answer 1

-Hinge joint
-Medially formed by trochlea of humerus and trochlear notch of ulna
-laterally formed by capitulum of humerus and head of radius
Motion: flexion/extension
Major support: -collateral ligaments :medial/lateral aka ulnar/radial)
-joint capsule

Question 2

Supporting Structures of elbow

Answer 2

Ligaments: -Ulnar collateral ligament (medial)

• radial collateral ligament (lateral)
• Bursa: -subtendinous olecranon bursa betwen triceps tendon and olecranon
• subcutaneous olecranon bursa

Question 3

Radio-ulnar Joint

Answer 3

Proximal Radio-ulnar Joint: -head of radius held in place by annular ligament (attaches to ulna @ anterior and posterior margins of radial notch, encircling head of radius)
Distal Radio-ulnar Joint: -Head of ulna articulation with ulnar notch
-pivot type of synovial joint: ulnar notch of radius rotates around head of ulna -stabilized by triangular ligament (fibrocartilage articular disc) that binds ends of ulna and radius together

Question 4

Forearm compartments

Answer 4

-anterior/flexor-posterior/extensor

Question 5

Anterior forearm

Answer 5

• attach on medial epicondyle
• predominantly median nerve innervation - 2 muscles are ulnar nerve
• 3 groups : -superficial, intermediate, deep (dont cross elbow)

Question 6

Pronator Teres

Answer 6

-superficial
Originates: on medial epicondyle
-superficial
Innervation: median nerve
Action: pronates forearm

Question 7

Flexor carpi radialis

Answer 7

-superficial
Originates: on medial epicondyle
-superficial
Innervation: median nerve
Action:flexes/abducts wrist

Question 8

Palmaris longus

Answer 8

-superficial
Originates: on medial epicondyle
-superficial
Innervation: median nerve
Action: flexes wrist

Question 9

Flexor carpi ulnaris

Answer 9

-superficial
Originates: on medial epicondyle
-superficial
Innervation: ulnar nerve
Action flexes/adducts wrist

Question 10

Flexor digitorum superficialis

Answer 10

Originates: on medial epicondyle
-intermediate
-Innervation: median nerve
Action: flexes PIP joints of digits 2-5

Question 11

Flexor pollicis longus laterally

Answer 11

Originates: on medial epicondyle
-Deep
Innervation: anterior inerosseous nerve
Action: flexes IP joints of thumb

Question 12

Flexus digitorum profundus medially

Answer 12

Originates: on medial epicondyle
-Deep
Innervation: - laterally: median nerve Medially: ulnar nerve
Action: flexes DIP joints of diits 2-5, can assist w wrist flexion

Question 13

Pronator quadratus distally

Answer 13

Originates: on medial epicondyle 
-Deep
Innervation: 
anterior interosseous nerve
Action: pronates forearm