Brachial Plexus

Question 1

Brachial Pexus

Answer 1

Musculocutaneous Nerve Median Nerve Ulnar Nerve Radial Nerve Axillary Nerve

Question 2

Infraclavicular

Answer 2

Divisions Cords Major Terminal Branches (brachial plexus)

Question 3

Supraclavicular

Answer 3

Roots (ventral rami) Trunks

Question 4

C5 Root

Answer 4

Dorsal Scapular Nerve

Question 5

C5, 6, 7

Answer 5

Long Thoracic Nerve

Question 6

Upper Trunk (C5 and C6)

Answer 6

Nerve to Subclavius Suprascapular Nerve

Question 7

Anterior Compartment Nerve Divisions

Answer 7

Lateral Cord Medial Cord

Question 8

Posterior Compartment Nerve Divisions

Answer 8

Posterior Cord

Question 9

Lateral Cord

Answer 9

Lateral Pectoral Nerve Musculocutaneous Nerve Median Nerve

Question 10

Medial Cord

Answer 10

Medial Pectoral Nerve Medial Brachial Cutaneous Nerve Medial Antebrachial Cutaneous Nerve Median Nerve Ulnar Nerve

Question 11

Posterior Cord

Answer 11

Upper Subscapular Nerve Lower Subscapular Nerve Thoracodorsal Nerve Radial nerve

Question 12

Upper Limb Innervation

Answer 12

Anterior Compartment of Arm (Brachium) Musculocutaneous Nerve Elbow Flexors Posterior Compartment of the Arm Radial Nerve Elbow Extensors

Question 13

Forearm Innervation

Answer 13

Antebrachium and Hand Anterior Compartment Ulnar and Median Nerve Posterior Compartment of Forearm and Hand Radial Nerve

Question 14

Upper Superior Trunk Lesion (brachial plexus injury)

Answer 14

Erb’s Palsy Excessive foreceful inc. in angle between neck and shoulder Most common Can occur in adults from fall on shoulder as well

Question 15

Clinical Presentation of Erb’s Palsy

Answer 15

Shoulder: Arm ABducted Arm internally rotated Elbow: Prontated Extended

Question 16

Nerve Deficits in Erb’s Palsy

Answer 16

C5 Spinal Nerve Root Axillary Nerve (deltoid & teres minor weakness) Suprascapular nerve (supra/infraspinatus weakness) Musculocutaneous nerve (biceps weakness) C6 Spinal Nerve Root Radial Nerve (brachioradialis and supinator weakness)

Question 17

Inferior/Lower Trunk Lesion

Answer 17

Klumpke’s Palsey From force abduction of arm Rare Associated w/ Homer Syndrome

Question 18

Clinical Presentation of Klumpke’s Palsey

Answer 18

Median and ulnar Nerves Wrist: extended Hand and fingers: MC/Prox. phalanx joint hyperextended Fingers flexed Claw hand

Question 19

Injuries to Radial Nerve

Answer 19

Axillary region (before triceps) Improper use of crutches weakness difficult to extend wrist difficult to extend fingers and open hand wrist drop posture

Question 20

Injuries to Radial Nerve: Spinal groove of humerus

Answer 20

Compression along midshalf of humerus Humeral fracture Sleep Palsey Clinical Presentation: difficult to extend wrist difficult to extend/straighten/open hand wrist drop

Question 21

Injuries to Axillary Nerve (C5, C6)

Answer 21

Causes: fracture of surgical neck of humerus Ant. dislocation of glenohumeral joint Rotator cuff repair surgery Clinical Presentation: Numbness in post. deltoid region difficulty ABducting arm diminished lateral rotation of arm deltoid muscle wasting (prolonged injury)

Question 22

Injury to Long Thoracic Nerve (C5-7) (innervation of Serratus Ant.)

Answer 22

Causes: Penetrating wound to axillary region Surgical removal of axillary lymph nodes Clinical Presentation: Cannot raise arm above 90 degrees winged scapula

Question 23

Injuries to Ulnar Nerve (C7, C8, T1)

Answer 23

Causes: fracture to medial epicondyle of humerus Entrapment of nerve in cubital tunnel Rotator cuff repair surgery Damage will involve wrist digit flexors and intrinsic hand muscles Clinical Presentation: Numbness/tingling in 4th/5th fingers worse when elbow is bent Weak grip/loss of flexion loss of ab/adduction of fingers

Question 24

Injuries to Median Nerve (C6-T1)

Answer 24

Causes: Fracture of humerus above condyles Entrapment by pronator teres Inflammation or irritation in carpal tunnel (syndrome) Damage affects wrist/digit flexors and intrinsic hand muscles (mainly those that move thumb) Clinical Presentation: Pain & Tenderness in ant. proximal Decreased sensation along median nerve course Hand of Benedication Ape hand (latrophy of thenar eminence) Inability to flex 2nd and 3rd digits

Question 25

Brachial Plexus Map

Answer 25

Question 26

Hand of Benedication (Median Nerve Damage)

Answer 26

Question 27

Cutaneous Innervation of Hand

Answer 27

Question 28

Ulnar Claw Simplified:

Answer 28

Nerve: Ulnar at wrist

Presentation: long standing

Digits: little and ring

Muscles paralysed: medial 2 lumbricals

Movements:

unopposed extension at the MCP joints

Unopposed flexion at IP joints

Question 29

Hand of Benediction Simplified

Answer 29

Nerve: Median at elbow or wrist

Presentation: when pt attempts to make fist

Digits: middle and index

Muscles Paralyzed: Lateral 2 lumbricals & lateral half of FDP

Movements:

Inability to flex at MCP and IP joints of middle & index

Voluntary flexion at MCP and IP joints of ring and little fingers