Upper Limb Palsies

Question 1

Scapular winging

Answer 1

• nerve involved: long thoracic n (nerve roots)
• most commonly affected during axillary lymph node dissection after mastectomy or with stab wounds
• muscle deficit: serratus anterior
• presentation: uneven scapula - unable to hold the medial border of the scapula against the rib cage on one side

Question 2

Erb-Duchenne Palsy

Answer 2

Nerve Involved: Upper Trunk (C5-C6)

Cause: Lateral traction on the neck during delivery or trauma associated with increase angle between shoulder and head

Muscle Deficit: Deltoid/Supraspinatus, Biceps Brachii, Infraspinatus

Presentation: Arm held in adduction and internal rotation w/ flexion and pronation at elbow

Question 3

Klumpke’s palsy

Answer 3

• injury to the lower or inferior trunk. most commonly cause separation of the C8-T1 nerve root attachments from the trunk
• cause of lesion: upward force on the arm,
  
  • during difficult delivery or reaching out to grab something while falling
  • also caused by thoracic outlet syndrome
• muscle deficit: intrinsic hand muscles
  
  • lumbricals - normally flex MCP and extend PIP and DIP
  • palmar and dorsal interossei
  • thenar and hypothenar muscles
• presentation: total claw hand
  
  • extension at MCP and flexion at IP joints
  • entire hand!

Question 4

Axillary Nerve Lesion

Answer 4

Cause of Injury: Fracture or Anterior Dislocation of the Humerus

Muscles Affected: Deltoid, Teres Minor, Triceps Brachii Long Head

Sensory Loss: Lateral Shoulder and Upper Arm

Presentation: Inability to abduct shoulder and potential atrophy of deltoid

Will also be a slight deficit in extension, flexion, and rotation

Question 5

musculocutaneous nerve

Answer 5

Nerve Involved: musculocutaneous nerve (peripheral nerve lesions

Cause: rarely directly injured but rather injured in association with lateral cord or upper/superior trunk injury

Muscle Deficit: biceps brachii, brachialis muscles, most prominent

Presentation: pt will have weak flexion at the elbow with loss of sensation in the proximal lateral forearm; decreased deep tendon reflex

Question 6

Radial Nerve Lesion (“Saturday Night Palsy”)

Answer 6

Cause: Midshaft Humeral Fracture or Compression within the Axilla

Muscle Deficit: Triceps Brachii, Extensor Carpi Radialis Longus and Brevis, Extensor Carpi Ulnaris

Sensory Deficit: Loss of sensation over posterior forearm and forearm and dorsal aspect of the hand

Presentation: Wrist drop due to an inability to extend the wrist or elbow, decreased grip strength due to loss of extension of the wrist

Question 7

Proximal nerve lesion (Pope’s blessing)

Answer 7

Nerve Involved: proximal median nerve

Cause: typically injured by a supracondylar fx of the humerus

Muscle Deficit: 1st and 2nd lumbricals (intrinsic hand muscle deficits are less pronounced in proximal lesions but can be seen when attempting to flex digits - ie, no claw hand at rest)

also hits FDS and FDP

Sensory deficit: loss of sensation over the lateral palm and thenar eminence

Presentation: pt will be unable to flex wrist or first, second, and third digits at the IP joints

Question 8

Distal Median Nerve Lesion (Median Claw or Carpal Tunnel)

Answer 8

Cause: Compression within the flexor retinaculum or laceration of the wrist

Muscle Deficit: Lumbricals (Normally flex MCP joint and extend IP joints)

Sensory Deficit: No sensory deficit, compression is distal to the superficial palmar branch

Presentation: Pain in wrist and possibly in distal forearm, When trying to extend fingers patient will be unable to extend 2nd and 3rd digits, Positive Tinnel’s sign at carpal tunnel, Positive Phalen’s Test

Question 9

proximal ulnar nerve lesion

Answer 9

Nerve Involved: proximal ulnar nerve

Cause: compression within cubital tunnel; can also be injured withmedial epicondylar fx

Muscle Deficit: FCU, FDP,

Sensory Deficit: loss of sensation over the medial dorsal hand, hypothenar eminence and proximal 4th and 5th digits

Presentation: at rest, no weakness; wrist deviates to radial side; unable to flex 4th and 5th digit when asked to make a fist - resulting in OK gesture;

Question 10

Distal Nerve Lesion (Ulnar Claw)

Answer 10

Cause: Fracture of hook of the hamate causing compression of nerve in Guyon’s canal or Compression of Guyon’s Canal from cycling or typing

Muscle Deficit: 3rd and 4th Lumbricals (Normally extend IP Joints and Flex MCP

Similar to Median Claw, Distal Nerve injuries make intrinsic hand muscle weakness more obvious. Makes it possible to see deficits at rest.

Sensory Deficit: Loss of sensation over the hypothenar eminence, as well as 4th and 5th digits

Presentation: At rest or trying to extend fingers, patient will be unable to extend IP joints of 4th and 5th Digits w/ loss of sensation over the hypothenar eminence and 4th and 5th digits