Lecture 16 - Anatomical Principles

Question 1

Describe the anatomical position and understand its importance in accurate anatomical communication

Answer 1

a. The anatomical position is:
i. Standing erect
ii. Head, toes, eyes directly forward
iii. Upper limb by the side with palms facing out
iv. Lower limbs together with toes forward

Question 2

32. List the correct anatomical terms to describe body planes, directions and anatomical relations

Answer 2

a. 3 major groups of planes
i. Coronal
ii. Sagittal
iii. Transverse/horizontal/axial

Question 3

Sagittal

Answer 3

i. Vertical plane divides body into left and right
ii. Sagittal planes offset from the midline are parasagittal plants
iii. Associated directional terms are medial and lateral

Question 4

Coronal (frontal) plane

Answer 4

i. Lies vertically
ii. At right angles to sagittal plane
iii. Associated directional terms: anterior (front) and posterior (back)

Question 5

Transverse (axial) plane

Answer 5

i. Runs horizontally from left to right
ii. Associated directional terms: superior (top) and inferior (bottom)

Question 6

Cut sections definitions

Answer 6

a. Longitudinal = cut in the sagittal plane
b. Transverse = cut in the transverse plane
c. Oblique = cut at an angle

Question 7

superficial

Answer 7

nearer to the surface

Question 8

intermediate

Answer 8

between a superficial and a deep structure

Question 9

deep

Answer 9

farther from the surface

Question 10

hands terms of comparison

Answer 10

palmar = palm
dorsal = back of hand

Question 11

feet terms of comparison

Answer 11

plantar = bottom of foot
dorsal = top of foot

Question 12

what are the main functions of muscle?

Answer 12

a. Produce movement
b. Maintain posture and body position
c. Stabilize joints
d. Generate heat

Question 13

what are the main properties of muscle tissue?

Answer 13

a. Electrical excitability
b. Contractility
c. Extensibility
d. Elasticity

Question 14

Distinguish between the three types of muscle tissue

Answer 14

a. Skeletal
i. Attaches to and covers the skeleton, voluntary contraction for overall body motility
b. Cardiac
i. Only exists in the heart, not voluntary contracts without direct stimulation from the nervous system
c. Smooth
i. Present in the walls of hollow organs (i.e. stomach, intestines, trachea); involuntary contractions (autonomic nervous system)

Question 15

Describe the structure of skeletal muscle

Answer 15

a. Muscle
i. Individual muscle cells, blood vessels, nerves
ii. Wrapped in epimysium
b. Fascicle
i. Bundle of individual muscle cells
ii. Wrapped in perimysium
c. Fibre
i. Individual muscle cell
ii. Wrapped in endomysium

Question 16

flexion

Answer 16

Bending, or decreasing the angle between body parts or bones

Question 17

extension

Answer 17

straightening, or increasing the angle between body parts of bones

Question 18

abduction

Answer 18

moving away from the midline

Question 19

adduction

Answer 19

moving towards to the midline

Question 20

medial (internal) rotation

Answer 20

rotation toward the midline

Question 21

lateral (external) rotation

Answer 21

rotation away from the midline

Question 22

elevation

Answer 22

movement in a superior direction

Question 23

depression

Answer 23

movement in an inferior direction

Question 24

protrusion/retrusion

Answer 24

movement anteriorly/posteriorly

Question 25

protraction

Answer 25

anterolateral movement of the scapula

Question 26

retraction

Answer 26

posterolateral movement of the scapula

Question 27

pronation

Answer 27

rotation of radius medially so that the palm faces posteriorly from anatomical position

Question 28

supination

Answer 28

rotating the radius laterally so that the palm faces anteriorly (anatomical position)

Question 29

dorsiflexion

Answer 29

flexion of the ankle joint, lifting front of foot and toes off the ground

Question 30

plantarflexion

Answer 30

bends the foot and toes toward the ground

Question 31

eversion

Answer 31

movement of the sole of the foot away from the midline

Question 32

inversion

Answer 32

movement of the sole of the foot away from the midline

Question 33

Name the common patterns of muscle fascicle arrangement

Answer 33

circular
convergent
parallel
pennate

Question 34

circular

Answer 34

i. Fascicle arranged into concentric rings
ii. Muscles surrounding external body openings e.g. mouth
iii. Example = orbicularis oris

Question 35

convergent

Answer 35

i. Broad origin, fascicles converge toward a single tendon of insertion (indirect insertion)
ii. Triangular or fan shaped
iii. Strongest contraction
iv. E.g. pectoralis major

Question 36

parallel

Answer 36

i. Length of fascicles runs parallel to the long axis of the muscle
ii. Greatest shortening of length during contraction
iii. Either straplike (e.g. sartorius – hip to inner thigh muscle) or spindle shaped with an expanded belly (e.g. fusiform – biceps brachii)

Question 37

pennate

Answer 37

i. Fascicles are short and attached obliquely (penna = feather)
1. Unipennate
a. Fascicles insert onto only one side of the tendon e.g. extensor digitorum longus
2. Bipennate
a. Fascicles insert onto the tendon from opposite sides of the muscle e.g. rectus femoris
3. Multipennate
a. Fascicles insert onto the tendon from many directions e.g. deltoid

Question 38

Define the terms origin and insertion and describe the types of connective tissue associated with skeletal muscle

Answer 38

b. Insertion – usually at distal end of muscle
c. Can have more than one of each
d. Connective tissue associated with muscle
i. Ligaments
1. Fibrous connections between bones, composed of collagen fibres, usually blend with periosteum of bones at the joint
ii. Tendon
1. Fibrous tissue linking a muscle bely attachment site at bone
iii. Aponeurosis
1. broad, flat connective tissue linking muscle belly to site of attachment; spread over a greater area than tendon
iv. Raphe
1. Line of fibrous tissue where one muscle joins another; usually a long attachment

Question 39

muscle contractions

Answer 39

i. Isometric = plank
ii. Concentric = raising barbell in bicep curl
iii. Eccentric = lowering barbell from bicep curl

Question 40

Prime mover = main muscle responsible for producing a specific movement i.e. concentric contraction

Answer 40

E.g. biceps brachii prime mover of elbow flexion

Question 41

Synergists – compliment action of prime mover by either adding extra force to same movement or reducing undesirable or unnecessary movements

Answer 41

E.g. brachialis synergist of biceps in elbow flexion

Question 42

Antagonist – muscle that opposes action of another muscle – eccentric contraction

Answer 42

E.g. triceps brachii opposes biceps during elbow flexion

Question 43

Fixator – steadies proximal parts of a limb while movements occur in distal parts – isometric contraction

Answer 43

E.g. rotator cuff muscle stabilise shoulder during elbow flexion

Question 44

Understand terminology for the naming of muscles

Answer 44

a. Location: Temporalis lies over the temporal bone
b. Shape: Trapezius is shaped like a trapezoid
c. Size: Maximus (largest); longus (long); brevis (short)
d. Number of origins: Biceps (two heads/origins)
e. Attachments: origin then insertion Ex. Sternocleidomastoid- Sternum and clavicle (origin) Mastoid process (insertion)

Question 45

Differentiate between superficial and deep fascial structures

Answer 45

a. Superficial – loose subcutaneous tissue (at/nearer to surface/skin)
b. Deep fascia – thin, rough sheet made primarily of collagen fibres

Question 46

Describe the principles of the neurovascular supply of muscles

Answer 46

a. One nerve, one artery and one or more veins serve each muscle
i. All enter or exit near centre/belly of muscle
b. Every skeletal muscle fibre is supplied with a nerve ending that controls activity
c. Has rich blood supply as contraction muscles needs a lot of energy, oxygen and nutrients as well as giving off large amounts of metabolic waste (removed through veins)