Midterm (Human Structure & movement)
Examples of 2nd Law of Motion
-If you use the same force to push a truck and push a car, the car will have more acceleration than the truck, because the car has less mass.
1st Law of Motion (Law of Inertia)
-Objects at rest will remain at rest unless acted upon by a force or object, and an object moving at a constant speed will continue to move at that speed unless acted upon by a force or object.
Types of Diathrodial Joints
-Plane (gliding) -hinge -pivot -condyloid -saddle -ball & socket
Example of 1st Law of Motion
-Your textbook will stay in the same spot on a table until you pick it up and move it
linear motion
Movement in a straight line.
Roles of Muscles
Prime mover, Synergist, Antagonist, Stabilizer, Neutralizer
base of 5th metatarsal
enlarged & prominent to serve as insertion for peroneus brevis & tertius
curvilinear motion
motion along a curved line
Purpose of the muscular system
movement
fiber arrangements
parallel and oblique
mastoid process
round projection on the temporal bone behind the ear
external rotation
turning a joint outward away from the median line
Where is the center of gravity?
Standing - upper sacrum Sitting - buttocks, thighs, and feet (It is located in the mid-line slightly anterior; second sacral vertebrae of an adult)
Resultant force
The overall force on a point or object
Medial
Toward the midline of the body
lateral epicondyle of the elbow
Your forearm muscles extend your wrist and fingers. Your forearm tendons — often called extensors — attach the muscles to bone. They attach on the lateral epicondyle. The tendon usually involved in tennis elbow is called the Extensor Carpi Radialis Brevis (ECRB).
subtalar joint
a joint in the ankle found between the talus and calcaneus
talocrural joint
a joint in the ankle found between the tibia, fibula, and talus
lateral
away from the midline of the body; on the outer side of
parallel fibers
axons parallel to one another and perpendicular to the planes of the Purkinje cells
flexion and extension
bending and extension of a limb
triaxial joint
bones are free to move in three directions around three axes(multiple directions), ex: Plane - bones may glide on or rotate with one another on any plane, Ball and socket - flexion/extension, adduction/abduction & rotation
epiphysis of long bone
ends of the bone, composed mostly of spongy bone enclosed by thin layer of compact bone
Distal
farther from the origin of a body part or the point of attachment of a limb to the body trunk
What does the sartorius do?
flexes leg at knee, flexes thigh at hip (longest muscle in the body)
3rd law of motion (action/reaction)
forces act in pairs. For every action, there is an equal but opposite reaction. Action/Reaction forces are equal and opposite, but DO NOT cancel out because they act on different objects. They are NOT balanced!
Oblique fibers
from the root above the apical fibers obliquely toward the occlusal to resist vertical and unexpected strong forces
What do the hamstrings do?
hip extension, knee flexion
Line of Gravity (LOG)
imaginary vertical line passing through the COG toward the center of the earth
What does the subtalar joint do?
inversion and eversion
3 arches of the foot
medial longitudinal, lateral longitudinal, transverse
sustentaculum tali
medial projection on the superior surface that supports the talus
open chain exercise
motions in which the distal segment (hand or foot) is free to move in space, without necessarily causing simultaneous motions at adjacent joints; limb movement only occurs distal to the moving joint and muscle activation occurs in the muscles that cross the moving joints
eccentric contraction
muscle lengthens as it maintains tension
concentric contraction
muscle shortens as it maintains tension
isotonic contraction
muscle shortens because muscle tension exceeds load
parallel force
occur in the same plane and in the same or opposite direction
isokinetic contraction
occurs when tension developed by muscle is maximal over full range of motion while shortening or lengthening at a constant speed.
ASIS (anterior superior iliac spine)
origin of sartorius
linear force
results when two or more forces are acting along the same line
Base of Support (BOS)
the area on which an object rests and that provides support for the object
Center of Gravity (COG)
the point at which the mass of a body or object is centered
pronation/supination
turning the hand to a palm down or palm up position
concurrent forces
two or more forces must act on a common point but must pull or push in different directions
biaxial joint
type of diarthrosis; a joint that allows for movements within two planes (two axes)
uniaxial joint
type of diarthrosis; joint that allows for motion within only one plane (one axis)
active insufficiency
when a 2 joint muscle contracts (shortens) across both joints simultaneously
passive insufficiency
when a 2 joint muscle is lengthened over both joints simultaneously
Types of joints and examples of each
-Fibrous (sutures, syndesmosis/ligamentous, gomphosis) (None to slight movement) Ex. Sutures between the skull -Cartilaginous Ex. Synchondroses-the articulation of the costal cartilage of the first rib with sternum and symphyses-intervetrebral joints and pubis symphysis of the pelvis are symphyses) -Synovial Ex. ball-and-socket joint (shoulder joint), hinge joint (knee), pivot joint (atlantoaxial joint, between C1 and C2 vertebrae of the neck), condyloid joint(radiocarpal joint of the wrist), saddle joint (first carpometacarpal joint
Ways in which muscles are named
-Size -Direction of fibers -Location -Number of divisions -Origin and insertion -Shape -Action
2nd Law of Motion (Law of Acceleration)
-The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
Purposes of skeletal system
-provide shape and support -enable movement -protect organs -stores materials -makes blood cells
spinous process
-sharp, slender projection -ex. spinous process of vertebra
Planes and axes of movement
..., to describe joint movements, reference is made to rotation about one or more of three axes to movement in one of three cardinal planes. Planes are perpendicular to each other.
cranial nerves
12 pairs of nerves that carry messages to and from the brain
spinal nerves
31 pairs of nerves arising from the spinal cord
foreman magnum
A passage in the skull bone through which the spinal cord enters the spinal column.
Example of 3rd law: Action/ Reaction
A person pushes off the ground to jump high.
screw home mechanism
A phenomenon that increases knee joint stability by locking the femur on the tibia (or vice-versa) when the knee is fully extended.
closed chain exercise
Can be performed with manual or mechanical resistance, using the patient's body weight, and in a dynamic and static fashion; Involve concentric, eccentric and isometric contractions; Provide load for muscles, joints, bones and noncontractile tissues; Stimulate mechanoreceptors within joints-->co-contraction-->increased stability; Improve muscle power/strength/endurance, stability, balance, and coordination; Can't be performed if NWB; Goor for improving stability in shoulder and hip girdles
Diaphysis (long bone)
Center portion of the thick compact bone (the shaft of the long bone)
Proximal
Closer to the origin of the body part or the point of attachment of a limb to the body trunk
Degrees of motion
Degrees of Motion (Goniometry) Quantifiable clinical measurement of joint motion Degrees of ROM
external auditory meatus
Ear canal (part of the temporal bone) (allows sound to travel in)
center of gravity for humans
In the anatomical position, the COG lies approximately anterior to the second sacral vertebra.
Types of bones
Long, Short, Flat, Irregular, Sesamoid(round)
isometric contraction
Muscle contracts but there is no movement, muscle stays the same length