Peripheral Nervous System Flashcards
What is a dermatome?
A region of skin innervated by a specific nerve root
Where is the C2 dermatome?
The back of the head and the middle section of the front of the neck
Where is the C3 dermatome?
The back of the neck and the bottom of the anterior neck and trapezius muscles
Where is the C4 dermatome?
From shoulder to shoulder anteriorly and posteriorly
Where is the C5 dermatome?
Along the bicep anteriorly and posteriorly from the shoulder down to the antecubital fossa
Where is the C6 dermatome?
The lateral forearm down to the thumb and forefinger
Where is C7 dermatome?
The middle finger and the majority of the medial palm and the corresponding back of the hand
Where is the C8 dermatome?
The medial palm and the pinky finger and ring finger and the corresponding back of the hand
Where is the T1 dermatome?
The medial forearm up to the elbow and antecubital forearm
Where is the T2 dermatome?
The tricep, up the medial aspect of the upper arm to cross the chest around the level of the manubriosternal joint and to arch across the back below the C4 dermatome
Where is the T3 dermatome?
The armpits and a horizontal strip of the chest and an arch of the back
Where is the T4 dermatome?
Just above the nipples across the chest and arching across the back
Where are the T5-T12 dermatomes?
They stripe across the chest from the nipples down to below the umbilicus, and arch across the back not as low down
Where is the L1 dermatome?
The waist area and the perigenital regions, and arches across the back
Where is the L2 dermatome?
L2 innervates a major part of the anterior thigh. It arches posteriorly from the lateral buttocks up to the small of the back
Where is the L3 dermatome?
L3 innervates the inferior portion of the anterior thigh, the knee and the area slightly below. Posteriorly, it innervates a small arch above the buttocks as well as the medial thigh
Where is the L4 dermatome?
The medial lower leg down below the medial malleolus
Where is the L5 dermatome?
The lateral lower leg and the medial 3 toes and superior foot
Where is the S1 dermatome?
The lateral 2 toes to the heel and back of the ankle
Where is the S2 dermatome?
A major region of the posterior legs
Where is the S3 dermatome?
The penis, part of the scrotum, and part of the buttocks
Where is the S4 dermatome?
The most distal part of the scrotum, and a small medial region of the buttocks
Where is the S5 dermatome?
Perirectal
What area of skin is innervated by the median nerve
The palmar. side of the thumb, index finger, middle finger, and the lateral 1/2 of the ring finger, and the radial aspect of the palm (C6 and C7 dermatomes)
