Chapter8 Flashcards
- synathroses_ —immovable
- amphiarthroses —slightly movable
- diarthroses —freely movable
functional classification of joints
- fibrous
- Cartilaginous
- synovial
strutural classifications of joints
- Bones joined by dense fibrous connective tissue
- No joint cavity
- Most are synathrotic (immovable)
Three types:
- Sutures
- syndesmoses_
- gomphoses
fibrous joints
- Rigid, interlocking joints containing short connective_ tissue fibers
- Allow for growth during youth
- In middle age, sutures ossify and are called synostoses
fibrous joints :sutures
- Bones connected by ligaments (bands of fibrous tissue)
- movement varies from immovable to slightly movable
Examples:
- synarthrotic distal tibiofibular joint
- diarthrotic interosseous connection between radius and ulna
Fibrous Joints: Syndesmoses
- Peg-in-socket joints of teeth in alveolar sockets
- Fibrous connection is the periodontal ligament
Fibrous Joints: Gomphoses
- Bones united by cartilage
- No joint_ cavity
Two types:
- Synchondroses
- Symphyses
Cartilaginous Joints
A bar or plate of hyaline cartilage unites the bones
All are synarthrotic
[ex. joint btw first rib and sternum]
Cartilaginous Joints: Synchondroses
- hyaline cartilage covers the articulating surfaces and is fused to an intervening pad of fibrocartilage
- strong, flexible amphiarthroses
[Ex.pubic symphysis]
Cartilaginous Joints: Symphyses
- All are diarthrotic
- Include all limb joints; most joints of the body
Features:
- articular cartilage:hyaline cartilage
- joint(synovial)cavity: small potential space
- articular(joint) capsule:
- outer fibrous capsule of dense irregular connective tissue
- inner synovial membrane of loose connective tissue
synovial joints
- capsular(intrinsic)—part of the fibrous capsule
- Extracapsular—outside the capsule
- Intracapsular—deep to capsule; covered by synovial membrane
in Synovial Joints the Three possible types of reinforcing ligaments:
components of synovial joint
- ligament
- joint cavity containing synovial fluid
- articular capsul with fibrous layer and synovial membrane
- periosteum
- flattened, fibrous sacs lined with synovial membranes
- Contain synovial fluid
- Commonly act as “ball bearings” where ligaments , muscles, skin, tendons , or bones rub together
bursae
Elongated bursa that wraps completely around a tendon
tendon sheath (friction reducing structure of synovial joint)
- Shapes of articular surfaces (minor role)
- Ligament number and location (limited role)
- Muscle tone , which keeps tendons that cross the joint taut_
- Extremely important in reinforcing shoulder and knee joints and arches of the foot
Stabilizing Factors at Synovial Joints
- Muscle attachments across a joint:
- origin_—attachment to the immovable bone
- insertion_—attachment to the movable bone
- Muscle contraction causes the insertion to move toward the origin
- movements occur along transverse, frontal, or sagittal planes
synovial joints: Movement
- nonaxial_—slipping movements only (tarsals)
- Uniaxial —movement in one plane
- biaxial—movement in two planes
- Multiaxial —movement in or around all three planes
Synovial Joints: Range of Motion