Neuro - Anat & Phys (Dermatomes & Reflexes)

Question 1

What is a way to remember the location of the landmark dermatome C2?

Answer 1

C2 - Posterior half of a skull “cap”

Question 2

What is a way to remember the location of the landmark dermatome C3?

Answer 2

C3- High turtleneck shirt

Question 3

What is a way to remember the location of the landmark dermatome C4?

Answer 3

C4 - Low-collar shirt

Question 4

What is a way to remember the location of the landmark dermatome T4?

Answer 4

T4 - At the nipple; Think: “T4 at the TEAT PORE”

Question 5

What is a way to remember the location of the landmark dermatome T7?

Answer 5

T7 - At the xiphoid process

Question 6

What is a way to remember the location of the landmark dermatome T10?

Answer 6

T10 - At the umbilicus (important for early appendicitis pain referral); Think: “T10 at the belly butTEN”

Question 7

What is a way to remember the location of the landmark dermatome L1?

Answer 7

L1 - At the inguinal ligament; Think: “L1 is IL (Inguinal Ligament)”

Question 8

What is a way to remember the location of the landmark dermatome L4?

Answer 8

L4 - Includes the kneecaps; Think: “Down on ALL 4’s (L4)”

Question 9

What is a way to remember the location of the landmark dermatome S2, 3, 4?

Answer 9

S2, 3, 4 - Erection and sensation of penile anal zones; Think: “S2, 3, 4 keep the penis off the floor”

Question 10

Where is diaphragm pain referred, and via which nerve? What other organ’s pain is referred to this same area?

Answer 10

Diaphragm and gallbladder pain referred to the right shoulder via the phrenic nerve

Question 11

Draw a human body and label the following landmark dermatomes: C2, C3, C4, T4, T7, T10, L1, L4, S2, S3. Shade in dermatomes based on region (i.e., cervical, thoracic, etc.) and fill in additional dermatomes (including V1-V3).

Answer 11

See p. 469 in First Aid 2014 for visual at bottom left

Question 12

With what nerve root is the biceps reflex associated?

Answer 12

Biceps = C5 nerve root

Question 13

With what nerve root is the triceps reflex associated?

Answer 13

Triceps = C7 nerve root

Question 14

With what nerve root is the patella reflex associated?

Answer 14

Patella = L4 nerve root

Question 15

With what nerve root is the achilles reflex associated?

Answer 15

Achilles = S1 nerve root

Question 16

Draw a stick figure, labeling the nerve roots according to the locations of the reflexes with which they are associated.

Answer 16

See p. 470 in First Aid 2014 for visual at top left

Question 17

What is a way to remember the nerve roots of all the important clinical reflexes?

Answer 17

Reflexes count up in order: S1, 2 - “buckle my shoes” (Achilles reflex); L3, 4 - “kick the door” (Patellar reflex); C5, 6 - “pick up sticks” (Biceps reflex); C7, 8 - “lay them straight” (Triceps reflex); Additional reflexes: L1, L2 - “testicles move” (Cremaster reflex); S3, S4 - “winks galore” (Anal wink reflex)

Question 18

With what nerve root(s) is the cremaster reflex associated?

Answer 18

L1, L2 - “testicles move” (cremaster reflex)

Question 19

With what nerve root(s) is the anal wink reflex associated?

Answer 19

S3, S4 - “winks galore” (anal wink reflex)

Question 20

In what patient populations are primitive reflexes found versus not found, and why?

Answer 20

Primitive reflexes: CNS reflexes that are present in a healthy infant, but are absent in a neurologically intact adult. Normally disappear within 1st year of life. These “primitive” reflexes are inhibited by a mature/developing frontal lobe. They may reemerge in adults following frontal lobe lesions –> loss of inhibition of these reflexes

Question 21

What is the Moro reflex? What is a nickname for it?

Answer 21

“Hang on for life” reflex - abduct/extend arms when startled, and then draw together

Question 22

What is the Rooting reflex? What is the significance of this?

Answer 22

Movement of head toward one side if cheek or mouth is stroked (nipple seeking)

Question 23

What is the Sucking reflex?

Answer 23

Sucking response when roof of mouth is touched

Question 24

What is the Palmar reflex?

Answer 24

Curling of fingers if palm is stroked

Question 25

What is the Plantar reflex? What is the name and significance of this reflex in an adult?

Answer 25

Dorsiflexion of large toe and fanning of other toes with plantar stimulation; Babinski sign - presence of this reflex in an adult, which may signify a UMN lesion

Question 26

What is the Galant reflex?

Answer 26

Stroking along one side of the spine while newborn is in ventral suspension (face down) causes lateral flexion of lower body toward stimulated side