Anatomy 2200 Midterm 1

Anatomical Position

everything facing forward

Superior (cranial)

above

Inferior (caudal)

Below

Anterior (ventral)

Towards the front of the body

Posterior (dorsal)

Towards the back of the body

Medial

Towards or at the midline of the body

Lateral

Away from the midline of the body

Proximal

Closer to the point of attachment of a limb

Distal

Farther from the point of attachment of a limb

Superficial (external)

Toward of at the body surface

Deep (internal)

Away from the body surface

Ipsilateral

On the same side

Contralateral

On opposite sides

Frontal (coronal) plane

divides the body into anterior and posterior parts

saggital plane

divides the body into a right and left side

Transverse plane

horizontal division of the body into upper and lower portions

Flexion/extension of upper limb at shoulder joint

Flexion/extension of a lower limb at hip joint

Flexion/extension of the forearm at the elbow joint

Flexion/extension of the leg at the knee joint

Flexion/extension of vertebral column

Abduction

movement away from the midline

Adduction

movement toward the midline

Lateral rotation

rotation away from the midline

Medial rotation

Rotation toward the midline

Divisions of PNS

Sensory and motor

Type of sensory nerve fibres

Somatic and visceral sensory

What is a spinal nerve

a mixed nerve, which carries motor and sensory info the spinal cord and the body

How many pairs of spinal nerves are there?

31 pairs

Divisions of the Motor Division

somatic and autonomic

Divisions of the spinal cord and # of nerves for each division

Cervical (8 but 7 vertebrae), Thoracic (12), Lumbar (5), Sacral (5), Coccygeal (1)

Divisions of ANS

SNS and PNS

Spinal nerve nomenclature

-Cervical nerves exit above corresponding vertebrae
-C8 is the transition point and it exits below the vertebrae
-All other nerves exit below

Components of spinal nerve

Spinal cord--->Dorsal (sensory) and ventral (motor) rootlets-->Dorsal (sensory) and ventral (motor) roots---> Spinal nerve (mixed)--->Dorsal and ventral ramus (mixed)

Dermatome

Area of skin innervated by the sensory fibers of a single spinal nerve
-help narrow down where a spinal injury is

What does the ventral ramus communicate to?

NMJ and sensory receptors in the skin

What is the Brachial Plexus? Where does it start and end

"Arm braid"
-Begins at neck, ends in axilla (armpit)

What rami is the brachial plexus formed by?

The ventral rami

Why is the brachial plexus formed by mixed nerves?

Ensures that multiple nerves supply 1 muscle. Will still be able to move even if one nerve is damaged.

Paresis

numbness and weakness

Paralysis

Complete inability to use muscles

Acronym to remember organization of brachial plexus

Really Thirsty? Drink Cold Bear (roots, trunks, divisions, cords, branches/terminal branches)

roots of brachial plexus

C5, C6, C7, C8, T1

trunks of brachial plexus

superior, middle, inferior

divisions of brachial plexus

anterior and posterior

cords of the brachial plexus

lateral, posterior, medial

terminal branches of brachial plexus

Musculocutaneous, median, ulnar, axillary, radial

What makes up musculocutaneous branch?

C5,C6,C7 (3 muskateers)

What makes up median branch?

C5,C6,C7,C8,T1 (5 mice)

What makes up Axillary branch?

C5,C6

What makes up the radial branch?

C5,C6,C7,C8,T1

What makes up the ulnar branch?

C8,T1 (2unicorns)

Acronym to remember root contributions

3 Muskateers Assassinate: 5 Mice, 5 Rats, 2 Unicorns

Brachial Plexus

Motor function of musculocutaneous branch

Arm flexors

Motor function of median branch

forearm and hand flexors

Motor function of ulnar branch

forearm and hand flexors

Motor function of radial branch

arm and forearm extensors

What part of brachial plexus is affected by wrist drop?

Can't extend wrist thus radial nerve isn't working

What part of the brachial plexus isn't working when you can't abduct shoulder, have weakness in arm+forearm flexors and extensors, and have loss of sensation to all parts of arm/hand?

C5 and C6 roots