Arm, Elbow, And Forearm

Question 1

Tri-joint complex

Answer 1

Humeroradial joint
Humeroulnar joint
Proximal radioulnar joint

Question 2

Humeroradial joint

Answer 2

Capitulum and radial head

Question 3

Humeroulnar joint

Answer 3

Trochlear and trochlear notch

Question 4

Proximal radioulnar joint

Answer 4

Radial head and radial notch

Question 5

Function of the Humeroradial and Humeroulnar joints

Answer 5

(Elbow) flexion/extension

Question 6

Function of the proximal radioulnar (forearm)

Answer 6

Supination/pronation

Radius rotates around ulna, from lateral to anterior during pronation

Question 7

Nursemaid elbow

Answer 7

Radial head dislocates from the annular ligament

Question 8

Functions of nursemaid elbow

Answer 8

Elbow extension and forearm pronation

Reduction: full supination and then flexion

Question 9

Carrying angle

Answer 9

Vertical axis of the humerus and forearm
Configurations of the articular surfaces
Males, 5 degrees
Female, 10-15 degrees

Question 10

What happens if there is too big carrying angle

Answer 10

Sprain of ulnar collateral ligaments

Valgus stress test

Question 11

Anterior arm muscle

Answer 11

Musculocutaneous nerve

Question 12

Posterior arm nerve

Answer 12

Radial nerve

Question 13

(Forearm) anteromedial component

Answer 13

Median and ulnar nerve- flexor compartment

Question 14

Median nerve

Answer 14

Crossing 2 heads of pronator teres

• continuous part: median nerve
• anterior interosseous nerve

Question 15

Ulnar nerve

Answer 15

Crossing two heads of flexor carpi ulnaris

• dorsal branch: sensory input of dorsal ulnar 1.5 digits
• palmar side: ulnar 1.5 digit sensory input and motor of intrinsic hand muscles

Question 16

Posterolateral component

Answer 16

Radial nerve and branches

• Divides into superficial and deep branches
• superficial branch: sensory input from dorsal radial head
• deep branch: posterior interosseous nerve after crossing supinator-posterior forearm muscles

Question 17

Grade III biceps tendon tear

Answer 17

Grade I: symptoms w/o visible damage
Grade II: visible incomplete tear, still partially functional
Grade III: complete tear w/o function

Question 18

Proximal and distal of grade III bicep tear

Answer 18

Proximal: most often long head tear (Popeyes arm) bump approaches to the elbow. May may not need surgery
Distal: whole tendon, surgical repair indicated, bump approaches to the shoulder. Heavy work, body builders who take steroids

Question 19

Radial nerve neuropathy

Answer 19

Mid numeral shaft fracture: most common radial nerve injury

Question 20

Radial nerve injury can cause what.

Answer 20

Saturday night palsy
Honeymoon palsy
Handcuff neuropathy
Crutch palsy
Squash palsy

Question 21

Golfers elbow: media, epicondylitis

Answer 21

Strain of flexor Caron radial is tendon
Similar symptoms w neighboring structure injury
-flexor carpi ulnaris and cubital tunnel syndrome

Question 22

Tennis elbow- lateral epicondylitis

Answer 22

Strain of extensor tendon: major cause is extensor carpi radial is brevis
Similar symptoms with neighboring structure injury
-brachioradialis
- radial tunnel syndrome: superficial radial and posterior interosseous nerve impingement