MS - Anat & Phys (Brachial plexus & Upper extremity nerves) Flashcards
Pg. 413-414 in First Aid 2014 Sections include: -Brachial plexus lesions -Upper extremity nerves
What are the main regions of the brachial plexus (in sequential order)?
Roots –> Trunks –> Divisions –> Cords –> Branches; Think: “Randy Travis Drinks Cold Beer”
Draw a schematic of the main regions and nerves of the brachial plexus, including the thoracic nerve.
See p. 413 in First Aid 2014 for visual at top of page
What condition results from a lesion of the upper trunk of the brachial plexus? Give 2 names for this condition.
Erb palsy (“waiter’s tip”)
What condition results from a lesion of the lower trunk of the brachial plexus? Give 2 names for this condition.
Claw hand (Klumpke palsy)
What condition results from a lesion of the posterior cord of the brachial plexus?
Wrist drop
What condition results from a lesion of the long thoracic nerve?
Winged scapula
What condition results from a lesion of the axillary nerve?
Deltoid paralysis
What condition results from a lesion of the radial nerve? Give 2 names for this condition.
“Saturday night palsy” (wrist drop)
What 2 symptoms result from a lesion of the musculocutaneous nerve?
Difficulty flexing elbow, variable sensory loss
What symptom results from a lesion of the median nerve, and what is its nickname?
Decreased thumb function, “Pope’s blessing”
What is affected by a lesion of the ulnar nerve, and what condition results?
Intrinsic muscles of hand, claw hand
What is another name for Erb palsy? With what injury is it associated?
Erb palsy (“waiter’s tip”); Traction or tear of UPPER (“Erb-er”) trunk: C5-C6 roots
What causes Erb palsy (“waiter’s tip”) in infants versus adults?
INFANTS - lateral traction on neck during delivery; ADULTS - trauma
What are 3 functional deficits seen with Erb palsy (“waiter’s tip”)? With what muscle(s) is each associated?
(1) Abduction (arm hangs by side) - Deltoid, supraspinatus (2) Lateral rotation (arm medially rotated) - Infraspinatus (3) Flexion, supination (arm extended and pronated) - Biceps brachii
Draw (or at least envision) the presentation of Erb palsy (“waiter’s tip”).
See p. 413 in First Aid 2014 for Erb palsy visual
What is another name for Klumpke palsy? With what injury is it associated?
Claw hand; Traction or tear of LOWER trunk: C8-T1 root
What causes Klumpke palsy in infants versus adults?
INFANTS - upward force on arm during delivery; ADULTS - trauma (e.g., grabbing a tree branch to break a fall)
What is the functional deficit seen with Klumpke palsy? With what muscle(s) is it associated?
Total claw hand: lumbricals normally flex MCP joints and extend DIP and PIP joints; Intrinsic hand muscles: lumbricals, interossei, thenar, hypothenar
With what injury is Thoracic outlet syndrome associated?
Compression of lower trunk and subclavian vessels
What are 2 causes of Thoracic outlet syndrome?
Cervical rib, trauma; Pancoast tumor
What is the functional deficit seen with Thoracic outlet syndrome? With what muscle(s) is it associated? Include symptoms associated with this.
Atrophy of intrinsic hand muscles; ischemia, pain, and edema due to vascular compression; Intrinsic hand muscles: lumbricals, interossei, thenar, hypothenar
What other condition has the same muscle deficit as Thoracic outlet syndrome?
Same as Klumpke palsy
With what injury is Winged scapula associated?
Lesion of long thoracic nerve
What are 2 causes of winged scapula?
Axillary node dissection after mastectomy, stab wounds
What is the functional deficit seen with Winged scapula? With what muscle is it associated?
Inability to anchor scapula to thoracic cage –> cannot abduct arm above horizontal position; Serratus anterior
Draw (or at least envision) the presentation of Klumpke palsy.
See p. 413 in First Aid 2014 for Klumpke palsy visual
Draw (or at least envision) the presentation of Winged scapula.
See p. 413 in First Aid 2014 for Winged scapula visual
What root(s) is (are) associated with the axillary nerve?
Axillary (C5-C6)
What are 2 causes of injury to the axillary (C5-C6) nerve?
Fractured surgical neck of humerus; Anterior dislocation of humerus
What are 3 characteristics of the presentation of axillary nerve injury?
(1) Flattened deltoid (2) Loss of arm abduction at shoulder (>15 degrees) (3) Loss of sensation over deltoid muscle and lateral arm
What root(s) is (are) associated with the musculocutaneous nerve?
Musculocutaneous (C5-C7)
What causes musculocutaneous nerve injury?
Upper trunk compression
What are 2 characteristics of the presentation of musculocutaneous nerve injury?
(1) Loss of forearm flexion and supination (2) Loss of sensation over lateral forearm
What root(s) is (are) associated with the radial nerve?
Radial (C5-T1)
What are 2 causes of radial nerve injury?
(1) Midshaft fracture of humerus; (2) Compression of axilla (e.g., due to crutches or sleeping with arm over chair (“Saturday night palsy”)
What are 3 characteristics of the presentation of radial nerve injury?
(1) Wrist drop: loss of elbow, wrist, and finger extension (2) Decreased grip strength (wrist extension necessary for maximal action of flexors) (3) Loss of sensation over posterior arm/forearm and dorsal hand
What is (are) the root(s) associated with the median nerve?
Median (C5-T1)
What are 2 causes of median nerve injury?
(1) Supracondylar fracture of humerus (proximal lesion) (2) Carpal tunnel syndrome and wrist laceration (distal lesion)
What are 4 characteristics of the presentation of median nerve injury?
(1) “Ape hand” and “Pope’s blessing” (2) Loss of wrist and lateral finger flexion, thumb opposition, lumbricals of 2nd and 3rd digits (3) Loss of sensation over thenar eminence and dorsal and palmer aspects of lateral 3 1/2 fingers with proximal lesion (4) Tinel sign (tingling on percussion) in carpal tunnel syndrome
What is (are) the root(s) associated with the ulnar nerve?
Ulnar (C8-T1)
What are 2 causes of ulnar nerve injury?
(1) Fracture of medial epicondyle of humerus “funny bone” (proximal lesion) (2) Fractured hook of hamate (distal lesion)
What are 4 characteristics of the presentation of ulnar nerve injury?
(1) “Ulnar claw” on digit extension (2) Radial deviation of wrist upon flexion (proximal lesion) (3) Loss of flexion of wrist and medial fingers, abduction and adduction of fingers (interossei), actions of medial 2 lumbrical muscles (4) Loss of sensation over medial 1 1/2 fingers including hypothenar eminence
What is (are) the root(s) associated with recurrent branch of median nerve?
Recurrent branch of median nerve (C5-T1)
What is the cause of injury to the recurrent branch of median nerve?
Superficial laceration of palm
What are 3 characteristics of the presentation of injury to the recurrent branch of median nerve (C5-T1)?
(1) “Ape hand” (2) Loss of thenar mucle group: opposition, abduction, and flexion of thumb (3) No loss of sensation
Draw and label the following upper extremity nerves, relating them to the arm & its bones: (1) Axillary (2) Median (3) Musculocutaneous (4) Radial (in spinal groove) (5) Recurrent branch of median (6) Ulnar.
See p. 414 in First Aid 2014 for visual on left at bottom of the page
Draw the palm of the hand, shading in and labeling the nerves innervating its different areas.
See p. 414 in First Aid 2014 for visual at bottom of the page
Draw the dorsum of the hand, shading in and labeling the nerves innervating its different areas.
See p. 414 in First Aid 2014 for visual at bottom of the page
Which branch of the radial nerve innervates the hand?
Radial nerve (superficial branch)
