Chapter 8
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Joints = Articulations
 Junctions between bones
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Bind skeletal system together
Make bone growth possible
Permit skeleton to change shape during
childbirth
Enable body to move in response to skeletal
muscle contraction
Fibrous connective tissue
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Joints vary considerably in structure & function
Classified by movement
 Synarthroses
 Amphiarthroses
 Diarthroses
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Classified by tissue type used to bind bones
 Fibrous
 Cartilaginous
 Synovial
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Dense CT
(collagenous)
Syndesmosis
 Ex. Tibia/Fibula
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Suture
 Ex. Skull
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Gomphosis
 Peg/socket
 Ex. Teeth and jaw
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Hyaline cartilage connects bones
Synchondrosis
 Bands of cartilage join bones
 Primary cartilaginous joint
▪ Ex. Epiphyseal plate
▪ Ex. 1st rib and manubrium
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Symphysis
 Hyaline cartilage attached to
fibrocartilage
 Secondary cartilaginous joint
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Most joints
Functions
 Resist wear
 Minimize shock
 Minimize friction
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Diarthrotic
 Ex. Knee
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Components:
 Articular cartilage
 Joint capsule
▪ Reinforced by ligaments
▪ Dense CT encasing joint
▪ Synovial membrane
▪ Synovial fluid
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Meniscus
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Fibrocartilage
Projects into joint cavity
Cushion
Distribute body weight
Bursa
 Sac of synovial fluid
 Located between skin
and bony projection
 Cushion tendon over
bone or another tendon
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Ball and socket
 rotational
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Condyloid
 No rotation
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Gliding
Hinge
 Flexion, extension
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Pivot
 Rotation
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Saddle
 Two plane motion
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Rotation
 Move part around axis
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Circumduction
 End follows circular
path
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Supination/Pronation
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Abduction/Adduction
Flexion/Extension
Hyperextension
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Protraction/retraction
Elevation/depression
Eversion/inversion
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Related to changes in collagen structure
Fibrous
 Accumulate bone matrix
 Stiffen or fuse
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Cartilaginous
 Loss of water and calcium
 Loss of elasticity
 Stiffening
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Synovial
 Circulation slows
 Collagen shortens and stiffens
 Lost elasticity, range of motion
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Rotator cuff
 4 muscles
 Tendons and fibrous joint
capsule
 Reinforce joint
 Support joint
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Why do you suppose that
shoulder joints are
relatively easily
dislocated?
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Cruciate ligaments
 Anterior (ACL)
 Posterior (PCL)
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Collateral ligaments
 Lateral (LCL)
 Medial (MCL)
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Menisci
 Medial
 Lateral
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Tendons
 Quadriceps
 Patella
Knee surgery
Femur
Arthroscopic
Scissors to remove tear
Tibia
Torn meniscus
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Due to injury,
infection, wear/tear
Sprains
 Tearing/overstretching
CT (cartilage,
ligaments, or tendons)
▪ Ex. Inverting ankle
▪ Sprain due to stretching lateral
ligaments
 RICE
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Bursitis
 Inflammation of
bursa
▪ Repetitive motion,
excessive pressure
 Rest, ice, NSAIDs,
cortisone
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Arthritis
 Inflamed, swollen, painful joints
 Rheumatoid
▪ Autoimmune disorder
▪ Most painful form
▪ Inflammation, thickening of
synovium, softening of
bone/cartilage, ossification in/of
joint
 Osteoarthritis
▪ Degenerative disorder
▪ Most common type
▪ Articular cartilage weakens,
disintegrates
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Chapter Assessments
 2-8, 12-17, 20, 23, 26-29, 31
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Integrative Assessments
 1-5