Chapter 8 Joints Flashcards
(22 cards)
Define joint and articulation
Articulation
- Site where two or more bones meet
Functions of joints
- Give skeleton mobility
- Hold skeleton together
Define the three functional and structural classifications
Structural- based on binding material
- Fibrous joints-Bones joined by dense fibrous connective tissue
- Cartilaginous joints-Bones united by cartilage
- Synovial joints-Articulating bones separated by fluid-filled joint cavity
Functional- based on amount of movement
- Synarthroses—immovable joints
- Amphiarthroses—slightly movable joints
- Diarthroses—freely movable joints
Describe the general structure of fibrous joints
- Bones joined by dense fibrous connective tissue
- No joint cavity
- Most immovable (synarthrotic)
Name the three major types of fibrous joints
Sutures
- Rigid, interlocking joints
- During development
- Contain short connective tissue fibers
- Allow for growth during youth
- In middle age, sutures ossify and fuse
- Immovable joints for protection of brain
Syndesmoses
- Bones connected by ligaments, cords or bands of fibrous tissue
- Fiber length varies so movement varies
- Found on ulna & radias.
Gomphoses
- Peg-in-socket joints
- Only example is teeth in alveolar sockets
- Fibrous connection is the periodontal ligament
Describe the general structure of cartilaginous joints.
- Bones united by cartilage
- No joint cavity and are not highly movable
Name the two major types of cartilaginous joints
Synchondroses
- Bar/plate of hyaline cartilage unites bones
- Are synarthrotic (immovable)
- Found joining sternum & rib.
Symphyses
- Fibrocartilage unites bone
- Hyaline cartilage is also present as articular cartilage on the bony surface
- Strong, flexible amphiarthroses
- found on pubic symphisis, intervertbral disc
Define Synarthrotic
immovable
Describe the distinguishing features of synovial joints.
-
Articular cartilage: hyaline cartilage
- Prevents crushing of bone end
-
Joint (synovial) cavity
- Small, fluid-filled space
-
Articular (joint) capsule
- External Fibrous layer
- Dense irregular connective tissue
- Inner Synovial membrane
- Loose connective tissue
- Makes synovial fluid
- External Fibrous layer
-
Synovial fluid
- Lubricates and nourishes articular cartilage
-
Reinforcing ligaments
- Capsular (majority)
- Extracapsular
- Intracapsular
-
Nerves and blood vessels
- Nerve fibers detect pain, monitor joint position and stretch
- Capillary beds supply filtrate for synovial fluid
Compare the structures and functions of bursae and tendon sheaths
Bursae
- Sacs lined with synovial membrane
- Contain synovial fluid
- Reduce friction where ligaments, muscles, skin, tendons, or bones rub together (like excersise ball)
Tendon Sheaths
- Elongated bursae wrapped completely around tendon subjected to friction
Name and describe the common body movements of synovial joints
Gliding
- One flat bone surface glides or slips over another similar surface (Ex: intercarpal & intertarsal joins “wave’’)
Angular movements
- Flexion, extension, hyperextension, abduction (away), adduction(toward midline), circumduction(circle)
Rotation
- Medial and lateral (turning of bone on its own long axis)
Name and describe the special body movements of synovial joints
supination
- radius & ulna parallel (soupbowl)
pronation
- Radius rotates over ulna
dorsiflexion
- Foot points up
plantar flexion
- Foot points “down”
inversion
- Foot flexes toward midline
eversion
- Foot flexes away from midline
Name and provide examples of the six types of synovial joints based on the movements allowed
Plane joints – nonaxial (intercarpal)
Hinge joints – uniaxial (elbow)
Pivot joints – uniaxial (atlas-axis)
Condyloid joints – biaxial (wrist)
Saddle joints – biaxial (thumbs)
Ball-and-socket joints – multiaxial (hip and shoulder)
Describe the knee and shoulder in terms of articulating bones, anatomical characteristics of joint, movements allowed and joint stability
Knee
- Hinge joint, uniaxial
- Largest, most complex joint of body
- Articulation of the femur with the tibia
- Three joints surrounded by a single joint cavity
- Contains 6 stabilizing ligaments
- At least 12 associated bursae
- Vulnerable to horizontal blows
Shoulder
- Ball-and-socket joint
- Head of humerus with glenoid cavity of scapula
- Most freely moving joint in body
- Stability sacrificed
Describe the hip in terms of articulating bones, anatomical characteristics of joint and explain acetabular labrum
- Ball-and-socket joint (multiaxial)
- Head of the femur articulates with acetabulum
- Good range of motion, but limited by the deep socket
-
Acetabular labrum
- Rim of fibrocartilage,
- Enhances depth of socket so hip dislocations rare
Name the most common joint injuries and discuss the problems associated with each injury
Cartilage tears
- Due to compression and shear stress
Sprains
- Stretch or tear of reinforcing ligaments
Dislocations
- Bones forced out of alignment
- Accompanied by sprains, inflammation, and difficulty moving joint
Compare and contrast the common types of arthritis
Osteoarthritis (OA)
- Common, irreversible, degenerative arthritis
- May reflect excessive release of enzymes that break down articular cartilage
- More cartilage is destroyed than replaced in badly aligned or overworked joints
Rheumatoid Arthritis (RA)
- Chronic, inflammatory, autoimmune disease (Immune system attacks own cells ) of unknown cause
- Signs and symptoms include joint pain and swelling (usually bilateral), anemia, osteoporosis, muscle weakness, and cardiovascular problems
Gouty Arthritis
- Deposition of uric acid crystals in joints and soft tissues, followed by inflammation
- Typically affects joint at base of great toe
- In untreated gouty arthritis, bone ends fuse and immobilize joint
Describe the cause and consequences of Lyme Disease
- Caused by bacteria transmitted by tick bites
- Symptoms: skin rash, flu-like symptoms, and foggy thinking
- May lead to joint pain and arthritis
-
Treatment-
- Long course of antibiotics
Nonaxial
(Synovial Joints: Range of Motion)
slipping movements only
Ex: intercarpal (inside hand)
Uniaxial
(Synovial Joints: Range of Motion)
movement in one plane
Ex: atlas-axis, found under head in neck, ability to rotate head
Biaxial
(Synovial Joints: Range of Motion)
movement in two planes
Ex: Wrist
Multiaxial
(Synovial Joints: Range of Motion)
movement in or around all three planes
Ex: Hip
