Articular System Flashcards
What are the two fundamental functions of Articulations?
- Mobility
2. Support
What are Articulations?
- They are joints
- Where two or more bones come together
- The joint is the weakest part of the skeleton
What are the two ways joints are classified?
- Functional Classification
2. Structural Classification
What is the functional classification of joints based on?
-Based on the amount of movement allowed at the joint
What are the three categories in functional classification of joints?
- Synarthroses
- Amphiarthroses
- Diarthroses
What is a Synarthroses and what classification of joints is it under?
- Immovable joints
- Functional classification
What is a Amphiarthroses and what classification of joints is it under?
- Slightly moveable joints
- Functional Classification
What is a Diarthroses and what classification of joints is it under?
- Freely moveable joints
- Functional Classification
What are the most common joints in the body?
Diarthrotic joints
Where are the Synarthrotic and Amphiarthrotic largely found?
Found in the Axial skeleton
What is the Functional Classification?
- Based on the amount of movement allowed at the joint
- Three categories
- Synarthroses: Immoveable joints
- Amphiarthroses: Slightly moveable joints
- Diarthroses: Freely moveable joints
- Diarthrotic joints are the most common in the body
- Synarthrotic and Amphiarthrotic are largely found in the axial skeleton
What is the structural classification of joints based on?
-Based on the material binding the bones together and whether or not a joint cavity is present.
What are the three categories in the structural classification of joints?
- Fibrous
- Cartilaginous
- Synovial
What are fibrous joints?
- Bones joined together by fibrous tissue are primarily dense connective tissue.
- No joint cavity
- Immoveable or Slightly moveable
- The amount of movement is based on the length of the connective tissue fibers connecting the bones
- There are three types of fibrous joints
What are the three different types of fibrous joints?
- Sutures Joint
- Syndesmosis Joint
- Gomphoses Joint
What are Sutures, what type of joint is it categorized under, and what classification of joints is it filed under?
Look at diagram on page 3 if needed
-“Seams” between the bones of the skull
-Wavy articulating bones for interlocking
-Immovable otherwise movement could damage the brain
-The only movement is to allow for skull to grow
Categorized under Fibrous Joints
Classified under the Structural Classification
What are Syndesmosis Joint, what type of joint is it categorized under, and what classification of joints is it filed under?
Look at diagram on page 4 if needed
-Bones connected exclusively by ligaments
-Connecting fibers are longer than sutures, but vary in length
-At the distal end of the tibia and fibula are short, thus little to no movement
-In between the ulna and radius fibers are long, thus a large amount of movement is possible
Categorized under Fibrous Joints
Classified under the Structural Classification
What are Gomphoses Joint, what type of joint is it categorized under, and what classification of joints is it filed under?
Look at diagram on page 4 if needed
-A peg-in-socket fibrous joint
-Articulation between the tooth and the bony alveolar socket
-Fibers are short, thus Immoveable
Categorized under Fibrous Joints
Classified under the Structural Classification
What are cartilaginous joints?
- Bones are joined together by cartilage
- No joint cavity
- Slightly moveable
- two types of cartilaginous joints
What are the two types of Cartilaginous joints?
- Synchondroses Joints
2. Symphyses Joints
What are Synchondroses Joints, what type of joint is it categorized under, and what classification of joints is it filed under?
Look at diagram on page 5 if needed
- Bones united by a bar or plate of hyaline cartilage
- Immovable
- Examples:
- Epiphyseal plates (aka growth plates)
- Joint between coastal cartilage of the first rib and manubrium of sternum - Categorized under Cartilaginous Joints
- Classified under the Structural Classification
What are Symphyses Joints, what type of joint is it categorized under, and what classification of joints is it filed under?
Look at diagram on page 6 if needed
- Bones united fibrocartilage
- Fibrocartilage is compressible and resilient
- Acts as a shock absorber and permits slight movement
- Examples:
- Intervertebral joints
- Pubic symphysis of the pelvis - Categorized under Cartilaginous Joints
- Classified under the Structural Classification
What are Synovial Joints?
Look at page 6 for diagram
- Bones are separated by a fluid filled joint cavity
- Free movement
- Nearly all joints are synovial
- There are 6 distinguishing features
1. Joint cavity
2. Synovial fluid
3. Articular capsule
4. Articular cartilage
5. Reinforcing ligaments
6. Nerves and blood vessels
What are the 6 distinguishing features of Synovial joints?
- Joint cavity
- Synovial fluid
- Articular capsule
- Articular cartilage
- Reinforcing ligaments
- Nerves and blood vessels
What are 6 different types of Synovial Joints?
- Plantar/gliding joint
- Hinge joint
- Pivot joint
- Condyloid joint
- Saddle joint
- Ball and socket joint
What is Plantar/Gliding joints?
- Two relatively flat Articular surfaces glide/side across one another
- Only Gliding Allowed
- Least moveable of synovial joints - Examples:
- Intercarpal Joints
- Intertarsal Joints
- Acromioclavicular joint
What is a hinge joint?
- Involves a concave and convex surface
- Permit angular motion in a single plane (uniaxial)
- Flexion/Extension only - Example:
- Knee
- Elbow
What is a condyloid joint?
Look at diagram on page 8 of notes
- Aka Ellipsoid joint
- An oval Articular surface of one bone articulates with elliptical surface of another bone
- Motion occurs in two planes
- Examples:
- Fingers
- Toes
- Atlantooccipital Joint
What is a pivot joint?
Look at diagram on page 9 in notes
- A cylindrical bone rotates inside a ring shaped bone
- Moniaxial
- Only permits rotation - Examples:
- Atlantoaxial Joint
- Radioulnar Joint
What is the saddle joint?
Look at the diagram on page 9 of notes
- Articulating surfaces fit together like a rider on a saddle
- One surface is concave and the other convex
- Example:
- Carpometacarpal joint
- Allows for opposition of the thumb
What is a ball and socket joint?
Look at the diagram on page 10 of the notes
- A round/spherical bone end articulates with a cup shaped cavity/depression of another bone
- Movements in all planes
- All movements can be performed, including circumduction
- Examples:
- Hip
- Shoulder
What are the movements at the synovial joints?
There are 17 movements
- Flexion
- Extension
- Abduction
- Addiction
- Internal/Medial Rotation
- External/Lateral Rotation
- Supination
- Pronation
- Inversion
- Eversion
- Plantarflexion
- Dorsiflexion
- Protraction
- Retraction
- Elevation
- Depression
- Circumduction
What is flexion movement at the synovial joint?
Bending of a joint bringing two bones closer together
What is extension movement at the synovial joint?
Straightening of a joint, moving two bones farther away from each other
What is abduction movement at the synovial joint?
Moving a limb laterally away from midline
What is adduction movement at the synovial joint?
Moving of a limb medically toward the midline
What is Internal/Medial Rotation movement at the synovial joint?
Rotation/turning a limb towards the midline
What is External/Lateral Rotation movement at the synovial joint?
Rotating/turning a limb away from the midline
What is supination movement at the synovial joint?
Turning upward of the forearm or foot
What is pronation movement at the synovial joint?
Turning downward of the forearm or foot
What is inversion movement at the synovial joint?
Movement of the sole of the foot toward the midline
What is eversion movement at the synovial joint?
Movement of the soul of the foot away from the midline
What is plantarflexion movement at the synovial joint?
Movement at the ankle to point the toes downward
What is dorsiflexion movement at the synovial joint?
Movement at the ankle to point the toes upward; pull toes toward the nose
What is protraction movement at the synovial joint?
Movement anteriorly; protrude
An example is: Punching
What is retraction movement at the synovial joint?
Movement posteriorly; retract
An example of this is jaw bone, head, & shoulder
What is elevation movement at the synovial joint?
Movement superiorly
An example of this is shrugging shoulders and your jaw
What is depression movement at the synovial joint?
Movement inferiorly
An example of this is pulling shoulders down also gravity pulling the shoulders down
What is circumduction movement at the synovial joint?
A combination of flexion/extension and abduction/adduction
An example of this is circling your arms
What is three types of joint injuries?
- Sprains
- Dislocations
- Cartilages tears
What is a sprain?
- Reinforcing ligaments are torn
- Commonly occur in the ankle, knee and elbow
- Partially torn ligaments will repair themselves, but heal slowly as they are poorly vascularized
- When completely torn surgery is recommended
What is a dislocation?
- Occurs when bones are forced out of the alignment
- Usually accompanied by sprains, inflammation, and immobility
- Commonly occurs in the fingers, thumb, and shoulder
What are cartilage tears?
- Example: Tearing of the knee Menisci
- Typically occur when compression and shear forces occur at the same time
- Does not have sufficient nourishment to repair itself
- It is recommended to get a menisci repair and not ameniscotomy
