Download Joints

Chapter 8
Classifying Joints
 Functions
 Flexibility for movement
 Hold bones together
 Structural Classification (binding tissue and cavity)
 Fibrous
 Cartilaginous
 Synovial
 Functional Classification (amount of movement)
 Synarthroses – immovable; axial skeleton
 Amphiarthroses - slightly movable; axial skeleton
 Diathroses - freely moveable; limbs
Organizing Joints
Fibrous Joints
Cartilaginous Joints
Synovial Joints
Binding material
Joined by fibrous
tissue
Joined by articular
(hyaline) cartilage
Separated by
synovial fluid cavity
Cavity Present
No
No
Yes
Functional Type
Synarthroses
Amphiarthroses
Diarthroses
Examples
Sutures
Syndesmoses
Gomphoses
Synchondroses
Symphyses
Joints of limbs
Fibrous Joints
 Sutures
 Only b/w skull bones
 Bind, but allow growth
 Complete as an adult (synostoses)
 Syndemoses
 Longer than sutures
 Length determines mov’t*
 Interosseous membrane and tibiafibula distal ends
 Gomphoses
 Tooth in alveolar socket
 Periodontal ligament
Cartilaginous Joints
 Synchondroses
 Temporary, become synostoses
 Epiphyseal plates and coastal
cartilage
 Symphyses
 Cartilage fused to fibrocartilage
pad/plate
 Strength with flexibility
 Intervetevbral discs and pubic
symphysis
Synovial Joints
 Articular cartilage
 Joint (synovial) cavity
 Articular capsule
 Fibrous capsule (ext-) DICT
 Synovial membrane (int-) LCT
 Synovial fluid
 Viscous, but thins with mov’t
 Reinforcing ligaments
 Double jointed = looser/stretchier ligmanents and capsule
 Rich blood and nerve innervation
 Fatty pads for cushioning (hip and knee)
 Menisci divide cavity and improve fit (knee and jaw)
Synovial Joints
 Preventing friction
 Bursae are flattend fibrous
synovial sacs
 Tendon sheaths are elongated
bursa wrapped around a tendon
 Stability
 Articular surface shape

Determine mov’t & some stability
 Ligaments
 Prevent excessive/undesirable mov’t
 Inadequate than stay stretched
(taffy) = snapping
 Muscle tone
 Tendons stay taut so reactive
Joint Articular Shapes
 Plane - articular surface is flat, nonaxial
 Intercarpal and –tarsals; slip 1 or 2 ways
 Hinge – cylindrical projection to a trough
 Elbow and interphalengeal; 1 plane of mov’t
 Pivot – rounded end into ring or “sleeve”
 C1 & C2 or radius & ulna; 1 plane of mov’t
 Condyloid - oval surface into a depression
 Metacarpophalangeal (knucles); 2 planes of
mov’t
 Saddle – concave and convex surface
 Carpometacarpal thumb joint; 2 planes of mov’t
 Ball and socket – spherical end with a cup-
like socket
 Shoulder or hip joint; 3 planes mov’t
Synovial Movements
 Gliding
 Slips surfaces across one another
 Flexion/extension
 Reduces angle of joint/ increases
angle
 Abduction/adduction
 Away from center/ toward
midline
 Pronation/supination
 Face or palm down/ face or palm
up
 Rotation/circumduction
 Turning on an axis/ making
small circles
 Inversion/eversion
 Turn sole medially/ turn sole
laterally
 Dorsiflexion/plantar
flextion
 Flex/ point
 Protraction/retraction
 Jaw out/jaw in
 Elevation/depression
 Lift superiorly/move inferiorly
Knee Joint




Single cavity w/ 3 joints
Capsule partially encloses
Strong vertical force, weak lateral
Patellar ligament (knee-jerk)
 Prevent hyperextension
anterior
cruciate
ligament
 Fibular and tibial collateral ligaments
 Prevent lateral and medial rotation w/ extension
 Anterior and posterior cruciate ligaments (tibial attach)
 Prevent forward sliding of tibia; back displacement of tibia or
forward femur
 Posteriorly, medially, up; anteriorly, laterally, up
 Lateral and medial meniscus
Temporomandibular Joint (TMJ)
 Mandibular condyle is egg-shaped
 Temporal bone is knob forward, concave fossa
 Side-to-side is lateral exclusion, unique to mammals
 Shallow socket = easy dislocation
 Reset: thumbs in molars, push inferior and posterior
 Pain from muscles tension
Clinical Terms
 Sprain: stretching/tearing of a ligament
 Dislocation (luxation): bones forced out of position
 Bursitis: inflammation on bursa; blow or friction
 Arthritis: synovial membrane thickens, production
decrease
 Osteoarthritis – degenerative; tissue thickens & bone spurs
formed
 Rheumatoid arthritis - autoimmune
 Gouty arthritis – uric acid accumulation in soft tissue joints
 Synovitis: inflammation of synovial membrane
 Tendinitis: inflammation of tendon sheaths, overuse;