Joints Flashcards
1
Q
Articulations/Joints
A
- Place where two bones come together
- Freely movable to limited to no apparent movement
- Structure correlated with movement
- Named by bones or parts united at joint – According to only one of articulating bones – By Latin equivalent of common name
2
Q
Classification of joints
A
Structural - major connective tissue types that bind bones
- fibrous
- cartilaginous
- synovial
Functional - based on degree of motion
- Synarthrosis: non movable
- Amphiarthrosis: slightly
- Diarthrosis: freely
3
Q
Fibrous Joints - Suture
A
- bones tightly bound by minimal fiber
- only skull
4
Q
Fibrous Joints - Syndemoses
A
Bones connected by ligaments
– E.g. tibiofibular ligament, interosseous membrane of radius/ulna
5
Q
Fibrous Joints - Gomphosis
A
Peg in socket joint
– Only found in teeth/alveoli
6
Q
Cartilaginous Joints
A
- Synchondrosis and Symphysis
7
Q
Synchondrosis
A
Hyaline cartilage unites bones
- Epiphyseal growth plates
- Costal cartilage-sternum
8
Q
Symphysis
A
- Fibrocartilage unites bones
- Pubic symphysis
- Intervertebral disc
9
Q
Synovial Joints
A
- Most common joints in body
- Most mobile joints
- Articular surfaces on bone with hyaline cartilage
- Completely enclosed joint capsule formed from ligamentous connective tissue
- Synovial fluid within capsule lubricates joint
- Some have meniscus or articular disc (e.g. knee, jaw joint)
10
Q
Components of Synovial Joints
A
Articular cartilage
Joint capsule
Synovial fluid
11
Q
Articular cartilage
A
- Resemble hyaline cartilage - Matrix contains more water comparatively
- Has no perichondrium
- Slick and smooth, so reduce friction
- Separated by thin film of synovial fluid
12
Q
Joint Capsule
A
- Dense and fibrous
- May be reinforced with accessory structures (tendons and ligaments)
- Continuous with periosteum of each bone
13
Q
Synovial Fluid
A
- Similar in texture to egg whites
- Produced at the synovial membrane
- Circulates from areolar tissue to joint cavity
- Percolates through articular cartilages
- Total quantity is less than 3 mL
14
Q
Functions of synovial fluid
A
- *Lubrication**
- With articular cartilage compression, synovial fluid is squeezed out and reduces friction between moving surfaces
- *Synovial fluid distribution**
- Provide nutrients and oxygen, as well as waste disposal for the chondrocytes of articular cartilages
- Compression and reexpansion of articular cartilages pump synovial fluid in and out of cartilage matrix
Synovial fluid absorption
- Distributes compression forces across articular surfaces and outward to joint capsule
15
Q
Joint accessory - Bursa
A
Bursa (a pouch)
- Small pocket filled with synovial fluid
- Often form in areas where tendon or ligament rubs against other tissues
- Reduce friction and act as shock absorbers
16
Q
Fat pads (accessory structure in knee)
A
- Adipose tissue covered by synovial membrane
- Protect articular cartilages
- Act as packing material for joint
17
Q
Meniscus (accessory structure in knee)
A
- Pad of fibrous cartilage between bones of synovial joint
- May subdivide joint cavity and affect fluid flow or allow variations in shapes of articular surfaces
18
Q
Tendons of quadriceps
A
Pass across joint
– Limit movement
– Provide mechanical support
19
Q
Acccessory ligaments
A
- strengthen, and reinforce joint
- Intrinsic ligaments
- Localized thickening of joint capsule
- Example: cruciate liagments of knee
20
Q
Ligament
A
- Separate from joint capsule
- May pass inside (intracapsular) or outside (extracapsular) the joint capsule
- Intracapsular example: cruciate ligaments
- Extracapsular example: patellar ligament
21
Q
Displacement (Luxation)
A
- Movement beyond normal range of motion
- Articulating surfaces forced out of position
- Can damage joint structures
- No pain from inside joint but from nerves or surrounding structures
22
Q
Types of synovial joints
A
Plane or gliding
- Saddle
- Hinge
- Pivot
- Ball-and-socket
- Ellipsoid
23
Q
Plane joints
A
Monoaxial
– Example: Articular processes between vertebrae
24
Q
Pivot joints
A
Monoaxial
– Example: Articulation between dens of axis and atlas
25
Saddle joint
Biaxial
– Example: Thumb
26
Hinge joint
Monoaxial
– Example: elbow, knee
27
Ellipsoid joint
Modified ball-and-socket
– Biaxial
– Example: Atlantooccipital joint
28
Ball and Socket joint
Multiaxial
– Examples: shoulder and hip joints
29
Types of movement
**Gliding**
**Angular**
- Flexion and Extension - Hyperextension, Plantar and Dorsiflexion
- Abduction and Adduction
**Circular**
**-** Rotation
- Pronation and Supination
- Circumduction
30
Flexion and Extension
31
Dorsiflexion and Plantar flexion
32
Abduction and Adduction
33
Rotation, Pronation and Supination
34
Circumduction
35
Elevation and Depression
36
Protraction and Retraction
37
Excursion
38
Opposition and Reposition
39
Inversion and Eversion
40
Rang of Motion
- Amount of mobility demonstrated at a given joint
Types:
– Active
– Passive
41
What is range of motion influenced by?
– Shape of articular surfaces forming joint
– Amount and shape of cartilage covering surfaces
– Strength and location of ligaments and tendons
– Location of muscles associated with joint
– Amount of fluid in and around joint
– Amount of use/disuse of joint
– Amount of pain in and around joint
42
Effects of Aging on Joints
Tissue repair slows
• Production of synovial fluid declines
• Ligaments and tendons become less flexible
• Decrease in ROM
43
Arthritis
- osteoarthritis - wear and tear
- rheumatoid - caused by transient infection or autoimmune disease
44
Joint infections
Lyme disease: tick vector
45
Gout
Metabolic disorders of unknown cause (idiopathic)
