Upper Limb Nerves Flashcards
From which spinal nerves is the brachial plexus formed?
C5 to T1
What is the source of the cutaneous nerve for the medial aspect of the upper part of the arm?
Derived from T2
What skin area does the upper lateral cutaneous nerve of the arm supply?
Over the lower ½ of the deltoid
What skin areas are supplied by the lateral cutaneous nerve of the forearm?
Anterior and posterior aspect of the lateral part of the forearm and the proximal part of the thenar eminence
Which nerve supplies the lateral aspect of the arm from the deltoid tuberosity to the elbow?
Lower lateral cutaneous nerve of arm (C5 & C6)
Which nerve supplies the posterior aspect of the arm?
Radial nerve
Which cutaneous nerves supply the shoulder over ½ of the deltoid?
Lateral supraclavicular nerves (C3 & 4)
What do the lateral and medial terminal divisions of the median nerve supply?
Palmar surface as well as the dorsal surface of distal and middle phalanges of the lateral 3-1/2 fingers
Which nerve supplies the lower half of the medial aspect of the arm?
Medial cutaneous nerve of arm (C8 & T1)
Which nerve supplies the middle of the back of the forearm?
Posterior cutaneous nerve of forearm (C5 – C8)
What does the intercostobrachial nerve supply?
Upper half of the medial aspect of the arm
Which nerve supplies the lateral two-thirds of the palm of the hand?
Palmar cutaneous branch of median nerve
What is the function of the medial cutaneous nerve of the forearm?
Supplies the anterior and posterior aspect of the medial part of the forearm
What is the cutaneous nerve of the arm that runs from the deltoid tuberosity to the elbow?
Cutaneous nerve of arm (C5 – C8)
Which nerve supplies the medial one-third of the palm of the hand?
Palmar cutaneous branch of ulnar nerve
What area does the superficial terminal branch of the ulnar nerve supply?
Palmar surface of medial 1-1/2 fingers
What area does the dorsal cutaneous branch of the ulnar nerve supply?
Medial 1/3 of the dorsum of the hand and the dorsal aspect of medial 1-1/2 fingers
What area does the superficial radial nerve supply?
Lateral 2/3 of the dorsum of the hand, proximal part of the thenar eminence, and dorsal aspect of the proximal phalanx of the lateral 3-1/2 fingers
Which dermatome includes the lateral part of the hand with the thumb and index fingers?
C6
Which spinal segment corresponds to the upper half of the deltoid?
C4
What does the C7 dermatome supply?
Middle finger and central part of hand and forearm
What does the T2 dermatome cover?
Medial aspect of upper part of arm and floor of axilla
What is a dermatome?
A segment of skin supplied by a specific segment of spinal cord
Which dermatome corresponds to the little and ring fingers?
C8
What areas does the C5 dermatome cover?
Lower half of deltoid, lateral aspect of arm, and upper part of lateral aspect of forearm
What areas are supplied by the T1 dermatome?
Medial aspect of upper part of forearm and lower part of arm
What is the segmental nerve supply of the upper limb?
The segmental nerve supply of the upper limb involves spinal nerves C3, C4, C5, C6, C7, C8, T1, T2
What is the significance of T1 in the upper limb nerve supply?
It contributes to the innervation of the upper limb
Which spinal nerve is associated with the hand in the diagram?
C8
Which spinal nerves are indicated in the segmental nerve supply of the upper limb?
C3, C4, C5, C6, C7, C8, T1, T2
Describe the anterior/posterior view of the segmental nerve supply of the upper limb.
The anterior view shows the distribution of nerves on the front side of the upper limb, while the posterior view shows the distribution on the back side
What spinal segment is responsible for radioulnar supination?
C8
Which spinal segments control wrist flexion and extension?
C6 and C7
Which myotome do the intrinsic muscles of the hand constitute?
T1
How are most muscles of the upper limb structured in relation to myotomes?
They are made up of more than one myotome, receiving motor fibers from several spinal cord segments
What spinal segment is responsible for shoulder flexion, abduction, and lateral rotation?
C5
Which spinal segments are responsible for radioulnar pronation?
C7 and C8
What is a myotome?
A unilateral embryological muscle mass receiving innervation from a single spinal cord segment or spinal nerve
Which spinal segments are involved in shoulder extension, adduction, and internal rotation?
C6, C7, and C8
Which spinal segments are involved in finger adduction and abduction?
T1
Which spinal segments are responsible for elbow flexion?
C5 and C6
