Elbow & Forearm Anatomy

Question 1

Identify the superficial muscles of the anterior arm and where they originates form

Answer 1

Pass, Fail, Pass, Fail (lateral to medial) - pronator teres, flexor carpi radialis, palmaris longus, flexor carpi ulnaris
All originate from medial epicondyle of humerus

Question 2

Flexor carpi ulnaris - AFI

Answer 2

Attachments - originates from medial epicondyle and also has a long origin from the ulna
Passes into the wrist and attaches to the pisiform carpal bone
Actions - flexion and adduction at the wrist
Innervation - ulnar nerve

Question 3

Palmaris longus - AFI

Answer 3

Attachments - originates from the medial epicondyle and attaches to flexor retinaculum
Actions - flexion at the wrist
Innervation - median nerve

Question 4

Flexor carpi radialis - AFI

Answer 4

Attachments - originates from the medial epicondyle and attaches to the base of metacarpals II and III
Actions - flexion and abduction at the wrist
Innervation - median nerve

Question 5

Pronator teres - AFI

Answer 5

Attachments - medial epicondyle and coronoid process of ulna
Attaches laterally to the midshaft of radius
Actions - pronation of the forearm
Innervation - median nerve

Question 6

Flexor digitorum superficialis - AFI

Answer 6

Attachments - originates from medial epicondyle and from radius
Splits into 4 tendons at wrist which travel through the carpal tunnel and attaches to middle phalanges of 4 fingers
Actions - flexes the metacarpophalangeal joints and proximal interphalangeal joints at the 4 fingers, and flexes at the wrist
Innervation - median nerve

Question 7

State the 3 deep muscles of the anterior forearm

Answer 7

Flexor digitorum profundus, flexor pollicis longus, pronator quadratus

Question 8

Flexor digitorum profundus - AFI

Answer 8

Attachments - originates from ulna and associated interosseous membrane
	At wrist, spits into four tendons, that pass through the carpal tunnel and attach to the distal phalanges of the four fingers
Action - flex the distal interphalangeal joints of the fingers, flexes at metacarpophalangeal joints and at the wrist
Innervation - medial half is innervated by the ulnar nerve
	Lateral half (acts on the middle and index fingers) is innervated by median nerve

Question 9

Flexor pollicis longus - AFI

Answer 9

Attachments - originates from anterior surface of radius and attaches to base of distal phalanx of thumb
Actions - flexes the interphalangeal joint and metacarpophalangeal joint of the thumb
Innervation - median nerve

Question 10

Pronator quadratus - AFI

Answer 10

Attachment - originates from anterior surface of ulna and attaches to anterior surface of radius
Actions - pronates forearm
Innervation - median nerve

Question 11

Identify the superficial muscles of the posterior forearm

Answer 11

Brachoradialis, extensor carpi radialis longus + brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris, anconeus

Question 12

Brachoradialis - AFI

Answer 12

Attachments - originates from lateral supracondylar ridge of humerus and inserts distal end of radius (radial styloid process)
Actions - flexion at elbow
Innervation - radial nerve

Question 13

Extensor carpi radialis longus - AFI

Answer 13

Attachments - originates from supracondylar ridge and inserts into metacarpal II
Actions - extends and abducts the wrist
Innervation - radial nerve

Question 14

Extensor carpi radialis brevis - AFI

Answer 14

Attachments - originates from lateral epicondyle and inserts into metacarpal III
Actions - extends and abducts the wrist
Innervation - radial nerve

Question 15

Extensor digitorum - AFI

Answer 15

Attachments - originates from lateral epicondyle and splits into 4
Central slip inserts into base of middle phalanx, two lateral slips insert into base of distal phalanx
Actions - extends medial 4 fingers at MCP and IP joints, extends wrist
Innervation - radial nerve

Question 16

Extensor digiti minimi - AFI

Answer 16

Attachments - originates from lateral epicondyle and inserts into small finger
Actions - extends little finger and contributes to extension at wrist
Innervation - radial nerve

Question 17

Extensor carpi ulnaris - AFI

Answer 17

Attachments - originates from lateral epicondyle and inserts into 5th metacarpal bone
Actions - extension and adduction at wrist
Innervation - radial nerve

Question 18

Anconeus - AFI

Answer 18

Attachments - originates from lateral epicondyle and inserts into olecrannon and ulna
Actions - extension of elbow joint
Innervation - radial nerve

Question 19

State the deep muscles of the posterior forearm

Answer 19

Supinator, abductor pollicis longus, extensor pollicis longus, extensor pollicis brevis, extensor indices

Question 20

Supinator - AFI

Answer 20

Attachments - originates from lateral epicondyle and posterior surface of ulna and inserts into posterior surface of radius
Actions - supinates forearm
Innervation - radial nerve

Question 21

Abductor pollicis longus - AFI

Answer 21

Attachments - originates from interosseous membrane and adjacent surfaces of radius and ulna and inserts into base of metacarpal I (thumb)
Actions - abducts thumb
Innervation - posterior interosseous nerve

Question 22

Extensor pollicis longus - AFI

Answer 22

Attachments - originates from interosseous membrane and posterior surface of ulna and inserts into distal phalanx of thumb
Actions - extends all joints of thumb (CMC, ICP, IP)
Innervation - posterior interosseous nerve

Question 23

Extensor pollicis brevis - AFI

Answer 23

Attachments - originates from interosseous membrane and posterior surface of radius and inserts into base of proximal phalanx of thumb
Actions - extends at MCP and carpometacarpal joints of thumb
Innervation - posterior interosseous nerve

Question 24

Extensor indicis - AFI

Answer 24

Attachments - originates from interosseous membrane and posterior surface of ulna and inserts into extensor hood of index finger
Actions - extends index finger
Innervation - posterior interosseous nerve

Question 25

Describe the joints at the lebow

Answer 25

- Humeroulnar joint between the trochlea of the humerus and the trochlear notch of the ulnar - Humeroradial joint between the capitulum of the humerus and the radial head - Proximal radio-ulnar joint located between the edge of the head of the radius and the radial notch of the ulna - Involved with supination and pronation alongside distal radio-ulnar joint

Question 26

Describe the bursa located at the elbow joint

Answer 26

- Olecranon bursa lies in the subcutaneous connective tissue overlying the olecranon - Reduces friction between bone and skin - Subtendinous bursa lies between the triceps tendon and the tip of the olecranon - Reduces friction between tendon and bone

Question 27

Identify the location of trochlea and capitulum on the humerus

Answer 27

Both located on the distal side | Capitulum located on the lateral side, trochlea located on the medial side

Question 28

Describe the structures that contribute to the strength of the elbow joint

Answer 28

Stability of elbow due to capsule, ligaments and muscles Annular ligament holds radial head in position Ulnar collateral ligament and radial collateral ligament also contribute to strength Constraints of arrangement of ulna and humerus means ball and socket joint of radio humeral cannot move in all directions

Question 29

Describe the arterial and venous structure of the arm

Answer 29

Brachial artery divides into radial and ulnar artery Common interosseous artery arises from ulnar artery Cephallic vein runs up lateral side, basillic vein runs up medial side of arm

Question 30

State the structures in the cubital fossa

Answer 30

Really Need Beer To Be At My Nicest | Radial nerve, biceps tendon, brachial artery, median nerve

Question 31

Describe the attachments and actions of the ligaments of the elbow joint

Answer 31

- Radial (lateral) collateral ligament attaches between the lateral epicondyle of the humerus and annular ligament of the radius - Keeps the radius and the capitulum close during pronation and supination of the forearm - Ulnar (medial) collateral ligament attaches between the medial epicondyle of the humerus and the coronoid process and olecranon of the ulna - Annular ligament stablises the proximal radioulnar joint by forming a collar around the radial head - Allows rotation of the radial head within the annular ligament during pronation/supination