Joints Flashcards
(37 cards)
Joint
a joint or articulation is a point of contact between two bones or bone and teeth
Arthritis
Joint inflammation
Arthroplasty
Replace of existing joint with artificial
Arthoroscopy
look inside
Arthraliga
joint pain
Osteoarthritis
articulating cartilage breaks done and bone is exposed. Bone wears against the joint surface.
Synovitis
inflammation of synovial
ROM
Range of motion
Joint Structural Classifications
- Joints are classified based on the presence or absence of space between articulating bones called a synovial cavity.
- Type of connective tissue binding bones together
Fibrous/Cartilaginous/Synovial Joints
Fibrous: No synovial cavity and bones are held together via a dense irregular connective tissue.
Cartilaginous Joint: No synovial cavity and bones held by cartilage.
Synovial: Synovial cavity present, and bones held together by dense irregular connective tissue of articulating capsules and accessory ligaments. Bones covered via hyaline cartilage
Joint Classifications: Function
- Synarthrosis ( immovable)
- Ampiarthrosis (slightly moveable)
- Diarthrosis (synovial joints that are freely moveable)
Fibrous Joints
Fibrous joints are composed of thin layer of dense irregular tissues.
1. Sutures: fibrous, held together via short fibers in skull. Short, edges
- Synostosis: replace suture with boney tissue ( begin as amphiarthric become synarthic)
- interlocking irregular boders give sutures strength to avoid fracture.
2. Syndemosis: fibrous joint where there is more space between bones and more dense irregular tissue than sutures.
- The irregular issue is arrnaged in bundle to form ligaments preventing much movement. Tibiofibular ligament
- Gomphoses: Also referred to as periodontal joint, forms the root of the tooth and the mandible.
- Dentoalveolar Joint: join between the tooth and the socket.
- Interosseous membranes: Large sheet of dense irregular tissue found between bones.
Cartilaginous Joints
Lacks a synovial cavity and allows no movement, articulations are tightly bound with fibrocartilage or hyaline.
1. Synchondrosis: articulation where the articulating cartilage is hyaline cartilage. ( epiphyseal plate , rib, manubrium, immovable joints, become boney in life)
2. Symphyses: articulating where the ends of bones are covered in hyaline cartilage but there is a large fibrocartilage disc connecting bones. (pubic symphysis, interveterbal discs, slightly moveable joints)
Synovial Joints
Synovial joints are unique and have synovial capsules between articulating bones. Allows for:
- increased movement
- Bones in joints are covered by aritculating cartilage (hyaline)
- Provides friction free movement
- Contains synovial fluid
Articular Capsule: surrounds synovial joint and encloses the synovial cavity.
1. Fibrous Membrane: dense irreg. attaches the periosteum of bones. Allows for movement and provides strength in one direction.
2. Ligaments: fibrous membranes arranged in bundles resit strain. Holds synovial joints together.
3. Synovial Membrane: inner layer of capsule composed of areolar tissue, adipose fat pads.
Synovial Fluid
- Secreted via synovial membrane
- Has Hyaluronic acid secreted by fibroblasts
Functions:
1. Reduce friction through lubrication
2. Absorb shock
3. Supplies oxygen, nutrients
4. Remove CO2 and waste products
5. Contain phagocytic cells to remove debris
Accessory Ligaments
- Extra capsular Ligaments: Lie outside of articulating capsules ( FIbula, tibia, collateral ligaments)
- TCL (MCL): Tibial Collateral Ligament: Prevent Medial movement of Tibia.
- FCL (LCL): Fibula Collateral Ligament: Prevent lateral movement of tibia - Intracapsular Ligaments: inside the articulating capsule.
- ACL: Anterior Cruciate Ligament- prevent knee hyperextension
- PCL: Posterior Cruciate Ligament- prevents tibia from sliding behind femor
Articulating Discs
Menisci articulating disc: crescent shaped fibrocartilage lis behind articulate surfaces and attaches to fibrous capsule.
Functions of Articulating Discs:
- Shock Absorption
- Better fit between articulating discs
- Weight distribution
- Compound Movements
- Evenly spread synovial fluid
Labra (Labrum)
Ball and socket joints (hip and shoulder)
- fibrocartilage lip. extends from edge of the socket
- Helps to deepen the joint and increase surface area of contact between the socket and the ball.
Bursa and Tendon sheaths
Bursae: saclike structures filled with little fluid
- Between skin and bones, tendons and bones, muscles and bones or bones and ligaments
- Reduces friction
Tendon Sheath: Synovial sheath reduce join friction.
- tube-like bursa that wrap tendons
- wrists, ankel, fingers
Synovial Joint Types
- plane joint–> non-axial movement (back/forth and side-side) Ex: intercarpal joints, intertarsal joint,
Hinge Joint
Convex surface of one bone fits into concave of another. Produced opening/closing movement or uni-axial movement (flex/extension). One bone remains still while other moves around axis. Ex: knee, elbow, ankle, interphalengeal joint
Pivot Joint
Rounded or pointed surface of one bone articulates with ring formed by another bone and by liagment. Produces uni-axial movement (rotation) Ex: atlanto-axial joint and radioulnar joint
Condylar Joint
The convex oval-shaped projection of one bone fits into oval depression of another. Permits bi-axial movement, 2 axis Ex: radiocarpal joint and metacarpophalengeal joint