Joints
what is articulation
A site where two or more bones meet
Fibrous joint
Bones joined by collagen fibers
no joint cavity
most immovable (synarthrotic)
Cartilaginous joints
Bones united by cartilage
No joint cavity and are not highly movable
Synovial joint features
Articulating bones separated by fluid-filled joint cavity
All are diarthrotic
Nearly all limb joints and most joints of body fall into this category
types of movement at synovial joints
gliding, Angular movements, Rotation, Special
Structural
based on binding material
types of fibrous joints
suture
syndesmoses
gomphoses
What are the 2 types of cartilaginous joints
Synchondroses
Symphyses
Distinguishing features
Articular cartilage: hyaline cartilage, Joint (synovial) cavity, Articular (joint) capsule, Synovial fluid, Reinforcing ligaments, Nerves and blood vessels
Gliding movements
One flat bone surface glides or slips over another similar surface
Examples: Intercarpal joints, Intertarsal joints, Between articular processes of vertebrae
Functional
Based on amount of movement
what are sutures
Held together with very short, interconnecting fibers, and bone edges interlock, only found in the skull.
Synchondroses function
Bar/plate of hyaline cartilage unites bones
Are synarthrotic (immovable)
what are structures associated with synovial joints
Bursae- Sacs lined with synovial membrane that contain synovial fluid and reduce friction where ligaments, muscles, skin, tendons, or bones rub together.
Tendon Sheaths- Elongated bursa wrapped completely around tendon subjected to friction
Angular Movements
Increase or decrease angle between two bones, Flexion, Extension, Hyperextension
Abduction—movement away from the midline Adduction—movement toward the midline Circumducti-Involves flexion, abduction, extension, and adduction of limb, Limb describes cone in space
Types of joints (synovial)
Plane joints, Hinge joints, Pivot joints, Condyloid joints, Saddle joints, Ball-and-socket joints
What are Syndesmoses joints
Bones connected by ligaments, cords or bands of fibrous tissue
Fiber length varies so movement varies
Symphyses function
Fibrocartilage unites bone (Hyaline cartilage is also present as articular cartilage on the bony surface)
Strong, flexible amphiarthroses
Three stabilizing factors
Articular surfaces and shape
Ligaments- number and location
Muscle tone
Rotation
Turning of bone around its own long axis
Medial rotation-Toward midline
Lateral rotation- away from midline
What are gomphoses joints
Peg-in-socket joints (Only example is teeth in alveolar sockets)
Fibrous connection is the periodontal ligament
range of motion
Nonaxial—slipping movements only
Uniaxial—movement in one plane
Biaxial—movement in two planes
Multiaxial—movement in or around all three planes
Special movements
Most are movements of specific joints
Supination and pronation of radius and ulna
Dorsiflexion and plantar flexion of foot
Inversion and eversion of foot