Bio 226 Chapter 8

Front 1

Three functional classifications

Back 1

Synarthroses—immovable

Amphiarthroses—slightly movable

Diarthroses—freely movable

Front 2

Three structural classifications

Back 2

Fibrous

Cartilaginous

Synovial

Front 3

Fibrous Joints

Back 3

•Bones joined by dense fibrous connective tissue

•No joint cavity

•Most are synarthrotic (immovable)

•Three types:

•Sutures

•Syndesmoses

•Gomphoses

Front 4

Fibrous Joints: Sutures

Back 4

•Rigid,interlocking joints containing short connective tissue fibers

•Allowfor growth during youth

•Inmiddle age, sutures ossify and are called synostoses

Front 5

Fibrous Joints: Syndesmoses

Back 5

•Bonesconnected by ligaments (bands of fibrous tissue)

•Movementvaries from immovable to slightly movable

•Examples:

•Synarthroticdistal tibiofibular joint

•Diarthroticinterosseous connection between radius and ulna

Front 6

Fibrous Joints: Gomphoses

Back 6

•Peg-in-socket joints of teeth in alveolar sockets

•Fibrous connection is the periodontal ligament

Front 7

Cartilaginous Joints

Back 7

•Bonesunited by cartilage

•Nojoint cavity

•Twotypes:

•Synchondroses

•Symphyses

Front 8

Cartilaginous Joints: Synchondroses

Back 8

•A bar or plate of hyaline cartilage unites the bones

•All are synarthrotic

Front 9

Cartilaginous Joints: Symphyses

Back 9

•Hyalinecartilage covers the articulating surfaces and is fused to an intervening padof fibrocartilage

•Strong,flexible amphiarthroses

Front 10

Synovial Joints

Back 10

•All are diarthrotic

•Include all limb joints; most joints of the body

Front 11

Distinguishingfeatures:

Back 11

1.Articularcartilage: hyaline cartilage2.Joint(synovial) cavity: small potential space

Front 12

Articular(joint) capsule

Back 12

Outer fibrous capsule of dense irregular connective tissue

Inner synovial membrane of loose connective tissue

Front 13

Synovialfluid

Back 13

Viscous slippery filtrate of plasma + hyaluronic acid

Lubricates and nourishes articular cartilage

Front 14

Threepossible types of reinforcing ligaments

Back 14

•Capsular(intrinsic)—part of the fibrous capsule

•Extracapsular—outsidethe capsule

•Intracapsular—deepto capsule; covered by synovial membrane

Front 15

Richnerve and blood vessel supply:

Back 15

•Nervefibers detect pain, monitor joint position and stretch•Capillarybeds produce filtrate for synovial fluid

Front 16

Bursae

Back 16

•Flattened,fibrous sacs lined with synovial membranes •Containsynovial fluid•Commonlyact as “ball bearings” where ligaments, muscles, skin, tendons, or bones rubtogether

Front 17

Tendon sheath

Back 17

•Elongatedbursa that wraps completely around a tendon

Front 18

Bursae

Back 18

•Flattened,fibrous sacs lined with synovial membranes •Containsynovial fluid•Commonlyact as “ball bearings” where ligaments, muscles, skin, tendons, or bones rubtogether

Front 19

Tendon sheath

Back 19

•Elongatedbursa that wraps completely around a tendon

Front 20

Stabilizing Factors at Synovial Joints

Back 20

•Muscletone,which keeps tendons that cross the joint taut

•Extremely important inreinforcing shoulder and knee joints and arches of the foot

Front 21

Synovial Joints: Movement

Back 21

•Muscleattachments across a joint:

•Origin—attachmentto the immovable bone

•Insertion—attachmentto the movable bone

•Musclecontraction causes the insertion to move toward the origin

•Movementsoccur along transverse, frontal, or sagittal planes

Front 22

Synovial Joints: Range of Motion

Back 22

•Nonaxial—slippingmovements only

•Uniaxial—movementin one plane

•Biaxial—movementin two planes

•Multiaxial—movementin or around all three planes

Front 23

Gliding Movements

Back 23

•Oneflat bone surface glides or slips over another similar surface

Front 24

Angular Movements

Back 24

Movementsthat occur along the sagittal plane:

•Flexion—decreasesthe angle of the joint

•Extension—increases the angle of the joint

•Hyperextension—excessiveextension beyond normal range of motion

Front 25

Movementsthat occur along the frontal plane

Back 25

•Abduction—movementaway from the midline

•Adduction—movementtoward the midline

•Circumduction—flexion+ abduction + extension + adduction of a limb so as to describe a cone in space

Front 26

Rotation

Back 26

•Theturning of a bone around its own long axis•Examples:•BetweenC1 and C2vertebrae•Rotationof humerusand femur

Front 27

•Movementsof radius around ulna:

Back 27

•Supination(turning hand backward)

•Pronation(turning hand forward)

Front 28

•Movementsof the foot:

Back 28

•Dorsiflexion(upward movement) •Plantarflexion (downward movement)

Front 29

Plane Joints

Back 29

•Nonaxialjoints

•Flatarticular surfaces

•Shortgliding movements

Front 30

Hinge Joints

Back 30

•Uniaxialjoints

•Motionalong a single plane

•Flexionand extension only

Front 31

Pivot Joints

Back 31

•Roundedend of one bone conforms to a “sleeve,” or ring of another bone•Uniaxialmovement only

Front 32

Condyloid (Ellipsoidal) Joints

Back 32

•Biaxialjoints

•Botharticular surfaces are oval

•Permitall angular movements

Front 33

Saddle Joints

Back 33

•Biaxial

•Allowgreater freedom of movement than condyloid joints

•Eacharticular surface has both concave and convex areas

Front 34

Ball-and-Socket Joints

Back 34

•Multiaxialjoints

•Themost freely moving synovial joints

Front 35

•Largest,most complex joint of body

Back 35

•Threejoints surrounded by a single joint cavity:•(1)Femoropatellar joint:•Planejoint•Allows gliding motion during knee flexion

Front 36

•(2)Lateraland (3) medialtibiofemoral jointsbetween the femoral condyles and the C-shaped lateral and medialmenisci (semilunar cartilages) ofthe tibia

Back 36

•Allowflexion, extension, and some rotation when knee is partly flexed

Front 37

•Capsularand extracapsular ligaments

Back 37

•Helpprevent hyperextension

Front 38

Intracapsularligaments

Back 38

•Anteriorand posterior cruciate ligaments•Preventanterior-posterior displacement•Resideoutside the synovial cavity

Front 39

•Reinforcingligaments:

Back 39

•Coracohumeralligament—helps support the weight of the upper limb•Threeglenohumeralligaments—somewhat weak anterior reinforcements

Front 40

•Reinforcingmuscle tendons:

Back 40

•Tendonof the long head of biceps:•Travelsthrough the intertubercular groove •Securesthe humerus tothe glenoid cavity

Front 41

•Fourrotator cuff tendons encircle the shoulder joint:

Back 41

•Subscapularis•Supraspinatus•Infraspinatus•Teresminor

Front 42

Elbow Joint

Back 42

•Radiusand ulna articulate with the humerus

Front 43

•Hingejoint formed mainly by trochlear notch of ulna and trochlea of humerus

Back 43

•Flexionand extension only

Front 44

•Anular ligament—surrounds head of radius

Back 44

•Twocapsular ligaments restrict side-to-side movement:•Ulnarcollateral ligament•Radialcollateral ligament

Front 45

Hip (Coxal)Joint

Back 45

•Ball-and-socketjoint

•Headof the femur articulates with the acetabulum

•Goodrange of motion, but limited by the deep socket

•Acetabularlabrum—enhances depth of socket

Front 46

Reinforcingligaments:

Back 46

•Iliofemoralligament

•Pubofemoralligament

•Ischiofemoralligament

•Ligamentumteres

Front 47

•Mandibularcondyle articulates with the temporal bone

Back 47

•Twotypes of movement•Hinge—depressionand elevation of mandible•Gliding—e.g.side-to-side (lateral excursion) grinding of teeth•Mosteasily dislocated joint in the body

Front 48

•Sprains

Back 48

•Theligaments are stretched or torn•Partialtears slowly repair themselves•Completeruptures require prompt surgical repair

Front 49

•Cartilage tears

Back 49

•Dueto compression and shear stress•Fragmentsmay cause joint to lock or bind•Cartilagerarely repairs itself•Repairedwith arthroscopic surgery

Front 50

•Dislocations (luxations)

•Occur when bones are forced out of alignment

•Accompanied by sprains, inflammation, and joint immobilization

•Caused by serious falls or playing sports

Back 50

•Subluxation—partialdislocation of a joint

Front 51

•Bursitis

Back 51

•Aninflammation of a bursa, usually caused by a blow or friction•Treatedwith rest and ice and, if severe, anti-inflammatory drugs

Front 52

•Tendonitis

Back 52

•Inflammationof tendon sheaths typically caused by overuse•Symptomsand treatment similar to bursitis