RAT 10 Flashcards
Describe some important functions of joints.
- joints enable movement
- joints provide stability
- joints allow long bones to lengthen
Functional Classification
according to the amount of motion they allow
Structural Classification
according to their anatomical features
Synarthrosis
doesn’t allow movement; greatest stability
Amphiarthrosis
only a small amount of movement; less stability than synarthrosis
Diarthrosis
freely moveable; least amount of stability
What are the 3 structural classification of joints?
Fibrous Cartilaginous Synovial
What do all fibrous joints have in common?
dense regular collagenous connective tissue
What are the structural and functional properties of a suture? Where are sutures located?
- very stable synarthrosis
- skull bones
- held together by very short collagen fibers that are part of dense regular collagenous connective tissue
What are the structural and functional properties of gomphoses?
- synarthrosis
- function: provide function and hold the tooth in place
Where are gomphoses located?
Between a tooth and its corresponding alveolus in the mandible/maxilla
Single form of Gomphoses
gomphosis
What is the name for the ligament in gomphoses?
Periodontal ligament
What are the structural and functional properties of symdesmoses?
Fibrous, Amphiarthroses
Where are syndesmoses located?
Between radius and ulna / between fibula and tibia
What do all cartilaginous joints have in common?
All held together by cartilage
What are the two types of cartilaginous joints?
Synchondroses
Symphyses
What type of tissue joins bones in a synchondrosis?
Hyaline
How is synchondrosis classified functionally?
Synarthroses
List three examples of synchondrosis
Epiphyseal plate
Intervertebral joint
Pubic symphysis
What type of tissue join bones in a symphysis?
Fibrocartilage pad
List two examples of a symphysis
Intervertebral joint
Pubic symphysis
Gliding Movement
When 2 bones slide on one another’s surfaces
Describe the lateral flexion of the following: head and trunk
moving something to the side
Abduction
The motion of a limb of appendage away from the midline of the body
Ex. Raising your arms to the side
Adduction
Movement of a limb toward the midline of the body
Ex. If you have your arms out out, bringing them back to your body
Circumduction
Where the limb moves in a circle
Ball and socket joint
Ex. Hip and shoulder
Internal (medial) Rotation
Rotational movement toward the median plane
External (lateral) Rotation
Rotation away from the center of the body
What joint movement is associated with the opposable thumb?
Saddle joint
What is reposition?
Restoration of an organ or tissue to its correct or original position
Elevation and Depression
- movements of the mandible or scapulae within the frontal plane
- moving lower jaw in a downward direction = depression
- moving mandible upward = elevation
Protraction
Scapulae move forward and to the side (anterolateral)
Retraction
Scapulae move back and toward the middle (posteromedial)
Supination and Pronation
When your palm or forearm faces up, it’s supinated.
When your palm or forearm faces down, it’s pronated
What type of tissues compose skeletal muscles?
Skeletal
Connective
Nervous
What is another term for a skeletal muscle cell?
Skeletal Muscle Fibers
Name the connective tissue that surrounds a muscle cell.
Muscle: endomysium
Fascicle: perimysium
Entire Muscle: epimysium
What composes a motor unit?
A single motor neuron and the multiple muscle fibers it controls
How do skeletal muscles work?
Contract in order to generate force
What are muscle knots?
Hyperirritable spots in muscle or fascial tissue (bands or sheets of connective tissue) known as myofascial trigger points
What causes muscle knots?
Repetitive motion
What provides most of the force for a given movement? What is an alternate name for this term?
Agonist; prime mover
Antagonist
Usually lies on the opposite side of a joint from its agonist partner and tends to oppose and slow the actions
Synergists
Muscles that work together with the agonist; help guide the movement and ensure it is smooth
Fixator
Muscles that hold a bone in place, an anchoring function that makes movement more efficient and reduces the risk of injury
Why are multiple muscles needed to create a smooth, coordinated movement?
A skeletal’s muscles action depends on the bones or parts to which it is attached and the joints that it crosses
Origin
The less moveable attachment point of a muscle on a bone
Insertion
The end of a muscle attached to the structure that will be moved when the muscle contracts
Force (lever system)
Tension generated by muscle contractions
Fulcrum (hinge point)
Joint at which the movement occurs
Load
Object you are trying to move
When does a lever work at a mechanical advantage?
A relatively small force can move a large load
Fulcrum must be located closer to the load being moved and farther away from the force that is moving the load
When does a lever work at a mechanical disadvantage?
The fulcrum is located farther from the load being moved and closer to the force moving the load
More force has to be applied in order to move the load
