Elbow, Forearm

Question 1

Elbow Joint

Answer 1

• complex
• 3 distinct joints
• 2 DoF (flex/ext, pro/sup)

Question 2

Carrying Angle

Answer 2

• anatomical position
• normal = 5-15 degrees
• if >15, cubitus valgus
• if <15, cubitus varus
• disappears when forearm pronates

Question 3

Synovial Membrane of Elbow

Answer 3

• fat pads in fossae to provide cushion at end of ROM
• fibrous membrane
• tendon attachments

Question 4

Elbow Ligaments

Answer 4

• radial collateral ligament (RCL)
• ulnar collateral ligament (UCL)
• anular ligament

Question 5

RCL

Answer 5

• one band going over anular ligament
• prevents active adduction

Question 6

UCL

Answer 6

• 3 bands (anterior, posterior, oblique)
• prevents active abduction

Question 7

Anular Ligament

Answer 7

• circular over radial head
• keeps radial head in place

Question 8

Tommy John Surgery

Answer 8

• for UCL (tears, overuse, stretching)
• 2 options = autograft from palmaris longus or plantaris, synthetic ligament

Question 9

Monteggia Fracture

Answer 9

• ulnar fracture w/ radial head dislocation
• surgery needed

Question 10

Galleazzi Fracture

Answer 10

• radial fracture w/ distal radioulnar joint dislocation
• surgery needed

Question 11

Elbow Vascular Supply

Answer 11

• anastomotic network
• brachial artery splits into radial a. and ulnar a.

Question 12

Humeroulnar Joint

Answer 12

• trochlea of distal humerus + trochlear notch of olecranon process of proximal ulna
• “elbow proper”
• elbow flexion & extension

Question 13

Humeroradial Joint

Answer 13

• capitulum of humerus + radial head
• “elbow proper”
• synovial, hinge (flex/ext)

Question 14

Proximal Radioulnar Joint

Answer 14

• radial head + radial notch of ulna
• synovial, pivot (supination/pronation)

Question 15

Median Cubital Vein

Answer 15

• in cubital fossa
• venopuncture (punctured to draw blood)

Question 16

Cubital Fossa

Answer 16

• superior border = line b/w epicondyles
• medial border = pronator teres
• lateral border = brachioradialis
• contents = tendon (biceps), artery (brachial), nerve (median)

Question 17

Radioulnar Articulation

Answer 17

• complex of 3 joints
• proximal radioulnar joint
• interosseous membrane
• distal radioulnar joint

Question 18

Forearm Supination/Pronation

Answer 18

• radius spins (functionally shortens) over relatively stable ulna
• at elbow: radial head spins on capitulum and slides on radial notch of ulna
• at wrist: ulnar notch of radius slides over ulnar head

Question 19

Common Flexor Tendon

Answer 19

• at medial epicondyle
• formed by 4 muscles … pronator teres, flexor carpi radialis, palmaris longus, flexor carpi ulnaris

Question 20

Superficial Anterior Forearm Muscles

Answer 20

pronator teres
flexor carpi radialis
palmaris longus
flexor carpi ulnaris

Question 21

What muscle is the only one of the four muscles attaching to the medial epicondyle not innervated by median nerve?

Answer 21

flexor carpi ulnaris, ulnar nerve

Question 22

Pronators

Answer 22

pronator teres
pronator quadratus
(both innervated by median nerve)

Question 23

Supinators

Answer 23

supinator
biceps brachii (both heads)

Question 24

Interosseous Membrane

Answer 24

• ligament that hold radius and ulna together
• increases SA for attachments
• transfer forces from distal radius to proximal ulna
• gaps for arteries to run through

Question 25

Quadrate Ligament

Answer 25

• runs from radial notch of ulna to neck of radius
• keeps radial head in place by ulna

Question 26

Oblique Cord

Answer 26

• runs from radial tuberosity to below the radial notch of ulna
• limits distal (inferior) motion of radius (“pulled elbow”)

Question 27

Distal Radioulnar Joint

Answer 27

• ulnar head + ulnar notch of radius
• synovial, pivot (supination/pronation)
• articular disc