Lecture 16 - Anatomical Principles Flashcards
Describe the anatomical position and understand its importance in accurate anatomical communication
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
- List the correct anatomical terms to describe body planes, directions and anatomical relations
a. 3 major groups of planes
i. Coronal
ii. Sagittal
iii. Transverse/horizontal/axial
Sagittal
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
Coronal (frontal) plane
i. Lies vertically
ii. At right angles to sagittal plane
iii. Associated directional terms: anterior (front) and posterior (back)
Transverse (axial) plane
i. Runs horizontally from left to right
ii. Associated directional terms: superior (top) and inferior (bottom)
Cut sections definitions
a. Longitudinal = cut in the sagittal plane
b. Transverse = cut in the transverse plane
c. Oblique = cut at an angle
superficial
nearer to the surface
intermediate
between a superficial and a deep structure
deep
farther from the surface
hands terms of comparison
palmar = palm
dorsal = back of hand
feet terms of comparison
plantar = bottom of foot
dorsal = top of foot
what are the main functions of muscle?
a. Produce movement
b. Maintain posture and body position
c. Stabilize joints
d. Generate heat
what are the main properties of muscle tissue?
a. Electrical excitability
b. Contractility
c. Extensibility
d. Elasticity
Distinguish between the three types of muscle tissue
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)
Describe the structure of skeletal muscle
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
flexion
Bending, or decreasing the angle between body parts or bones
extension
straightening, or increasing the angle between body parts of bones
abduction
moving away from the midline
adduction
moving towards to the midline
medial (internal) rotation
rotation toward the midline
lateral (external) rotation
rotation away from the midline
elevation
movement in a superior direction
depression
movement in an inferior direction
protrusion/retrusion
movement anteriorly/posteriorly
protraction
anterolateral movement of the scapula
retraction
posterolateral movement of the scapula
pronation
rotation of radius medially so that the palm faces posteriorly from anatomical position
supination
rotating the radius laterally so that the palm faces anteriorly (anatomical position)
dorsiflexion
flexion of the ankle joint, lifting front of foot and toes off the ground
plantarflexion
bends the foot and toes toward the ground
eversion
movement of the sole of the foot away from the midline
inversion
movement of the sole of the foot away from the midline
Name the common patterns of muscle fascicle arrangement
circular
convergent
parallel
pennate
circular
i. Fascicle arranged into concentric rings
ii. Muscles surrounding external body openings e.g. mouth
iii. Example = orbicularis oris
convergent
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
parallel
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)
pennate
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
Define the terms origin and insertion and describe the types of connective tissue associated with skeletal muscle
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
muscle contractions
i. Isometric = plank
ii. Concentric = raising barbell in bicep curl
iii. Eccentric = lowering barbell from bicep curl
Prime mover = main muscle responsible for producing a specific movement i.e. concentric contraction
E.g. biceps brachii prime mover of elbow flexion
Synergists – compliment action of prime mover by either adding extra force to same movement or reducing undesirable or unnecessary movements
E.g. brachialis synergist of biceps in elbow flexion
Antagonist – muscle that opposes action of another muscle – eccentric contraction
E.g. triceps brachii opposes biceps during elbow flexion
Fixator – steadies proximal parts of a limb while movements occur in distal parts – isometric contraction
E.g. rotator cuff muscle stabilise shoulder during elbow flexion
Understand terminology for the naming of muscles
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)
Differentiate between superficial and deep fascial structures
a. Superficial – loose subcutaneous tissue (at/nearer to surface/skin)
b. Deep fascia – thin, rough sheet made primarily of collagen fibres
Describe the principles of the neurovascular supply of muscles
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)
