Chapter 8 Part 1) Joints Flashcards
1
Q
Joints (Classifications)
A
- Articulations where two (or more) bones meet.
- Give the skeleton mobility and hold it together
- Two Classifications
- Structural) Based on what material binds the joints and weather a cavity is present
- Ex) Fibrous, Cartilaginous, Synovial (cavity)
- Funtional) Based on type of movment the joint allows
- Ex) Synarthoses, Amphiarthroses, Diarthroses
2
Q
Fibrous Joint
A
- Classifies the material the joint is being made of. Bones are joined by Dense Fibrous Connective Tissue.
- No Joint cavity. Most are immovable. (synarthrotic)
3
Q
Three Types of fibrous joint
A
- Sutures) Ridgid interlocking skull joints
- made of short connective tissue fibers that allow for some streatching.
- These sutures ossify when growing stops and become synostoses
- Syndesmoses) Bones connected by ligaments and bands of fibrous tissue
- Fibers varry in length
- Short fibers) little to no movment (ex inferior tibiofibular joint)
- Longer fibers) some movment (ex interosseous membrane connecting radius and ulna)
- Gomphoses) Peg-In socket joints
- held in place by the peridontal ligament
- Only found in the teeth in humans.
4
Q
Cartilaginous Joints
A
- Classified by the material that binds the joint. Joint is bound by cartlidge.
- Do not have a joint cavity
- Not very movable.
5
Q
Two types of Cartilaginous Joints
A
- Syncondroses) Bar or plate of hyaline cartlidge unites bone.
- Almost are are synarthrotic (immovible)
- Ex) ephiphyseal growth plate (becomes synostoses if the joint closes and becomes bone)
- Symphyses) Fibrocartlidge unites bones
- Hylaine is also present, but fibrocartlidge is main
- Strong, amphiarthrotic (slightly movable) joints
6
Q
Synovial Joints
A
- Joint has a cavity. Bones are seperated by a fluid filled cavity,
- All are diarthotic (freely movable)
- Include almost all of the limbs
- Charcteristics of Synovial Joints
- Have 6 general features
- Have Bursae and Tendon Sheaths
- Differing levels of Stability
- Allow several Movments
- 6 Diffrent types.
7
Q
General Structure of Synovial Joints (6 points)
A
- Articular Cartlidge) Hylaine cartlidge covers the ends of bones. This prevents the crushing of bones.
- Joint (synovial) cavity) small, fluid filled space that is unique to synovial joints
- Articular Joint Capsule) 2 Parts
- External Fibrous Layer) Dense irregular connective tissue connects periostia of both bones
- Inner Synovial membrane) Loose connective tissue that makes synovial fluid.
- Synovial Fluid) Viscous fluid that lubricates joints and removes debris.
- Reienforcing Ligaments) three types
- Capsular) thickened part of fibrous layer
- Extracapsular) Outside the capsule
- Intracapsuler) Deep to capsule but superior to synocial membrane.
- Nerves and Blood Vessels.
- Other structures
- Fatty pads)
- Artiucular dics) meniscui.
8
Q
A
9
Q
Bursae and Tendon Sheaths
A
- Bags of synovial fluid that act as lubricating ball bering.
- Not part of the joint but associated with them
- Bursae) Reduce friction where ligaments, muscles, skin, tendons, or bones rub together.
- Tendon Sheaths) Elongated bursae that wrap around tendons to reduce friction (hot dog)
10
Q
Factors influncing stabilty of synovial joints
A
- Shape of Articular Surfaces) plays a minor role in stability.
- Determines what movments are possible at a joint but do not provide much stability
- Ligament number and location) Plays a limited role
- More ligaments = more stable
- Muscle tone) most important
- Keeps tendons taught as they cross joints
- Keeps muscles ready to react to stimuli.
11
Q
Movments Allowed by Synovial Joints
A
- Muscles attach to bones in at least two points
- Origin) attacment to immovible bone (pulls toward)
- Inscertion) attacment to movible bone (pulls on)
- Movment can occur in transverse, sagital, or frontal planes
- Nonaxial) slipping movment only
- Uniaxial) movment in one plane
- Biaxial) movment in two planes
- Multiaxial) movment in three planes
12
Q
Gliding Movments
A
- One flat bone glides/slips over another similar surface. This occurs without rotation
- EX) intercarpal joints, Intertarsal Joints, Between articular process’ of vertebrae
13
Q
Angular Movments (6 total)
A
- Increase/decrease the angle between two bones
- Occurs along the sagital plane
- Flexion) decrese of joint angle
- Extension) increases joint angle
- Hyperextension) joint goes beyond anatomical position
- Abduction) movment away from midline
- Adduction) movment twoards midline
- Circumduction) Flexion, abduction, extension and abduction of a limb (arm Circles)
14
Q
Rotation
A
- Turning of a bone on its long axis
- Medial) to midline
- Lateral) away from midline
15
Q
Supination and Pronation
A
- Supination) palms face anteriorly
- Pronation) Palms face posteriorly
