Articulations - PowerPoint Presentation

Slide1

Articulations

(Joints)Slide2

Articulations

Body movement occurs at joints (articulations) where 2 bones connect

Joint

Structure

Determines direction and distance of movement (range of motion)

Joint strength decreases as mobility increasesSlide3

9-3

Naming of Joints

Usually derived from the names of the articulating bones. Slide4

Joints



Articulations

Point at which two bones join together

Allow movement

Transmit forces

Anatomy

Capsule or ligaments

Synovial membrane

Articular cartilageJoint space filled with synovial fluidSlide5

Structural Classifications

BonyFibrousCartilaginousSynovial Slide6

Functional Classifications

Synarthrosis:no movement

Amphiarthrosis

:

little

movement

Diarthrosis

:

more movementSlide7

Classifications

Structural Categories:

Fibrous

Cartilaginous

Synovial

Functional Categories:

Synarthroses

—immoveable

Amphiarthroses—slightly moveableDiarthroses—freely moveableSlide8

Synarthroses

Immoveable joints

Lack synovial cavity

Held together by fibrous connective tissue

Structural types:

Sutures

Syndesmoses

Gomphoses

Slide9

Synarthroses

Sutures

Thin layer of dense fibrous connective tissue

Unites bones of skull

Syndesmosis

Joints where bones connected by ligaments

i.e. fibula/tibia and radius/ulna

Gomphosis

Conical process fits into socket and is held in place by ligaments

i.e. tooth in alveolus (socket), held in place by

peridontal

ligamentSlide10

Amphiarthroses

Slightly moveable

Connected by hyaline cartilage or fibrocartilage

i.e. ribs to sternum or vertebraeSlide11

Diarthroses



Synovial joints

Freely moveable

Ends of opposing bones are covered with articular cartilage

Separated by joint cavity

Components of joints enclosed in dense fibrous joint capsuleSlide12

Synovial jointSlide13

Synovial Joint Anatomy

Articular capsuleJoint capsuleConsists of bundles of collagen and functions to maintain a relative joint positionSlide14

Synovial Joint Anatomy

Synovial Membrane and Synovial FluidLines the synovial joint(articular) capsuleMade of connective tissue with flattened cells

Synovial fluid acts as a lubricant.

Able to vary its viscosity (thicker with slower movements and it thins with faster movements)Slide15

Synovial Fluid

Contains slippery proteoglycans secreted by fibroblastsFunctions

of Synovial Fluid

Lubrication

Nutrient distribution

Shock absorptionSlide16

Synovial Joint Anatomy

-Articular Cartilage

Hyaline cartilage: Found on the articular ends of our long bones

Pad articulating surfaces within articular capsules:

prevent bones from touching

Smooth surfaces lubricated by synovial fluid:

reduce friction

Fibrocartilage:

cushioning type of cartilage

Found in the menisci in our knees, intervertebral disks, pubic symphysis-Elastic cartilage: Found in the external earSlide17

Synovial Joint Anatomy

BursaFluid-filled sac of synovial tissue found in our synovial joints.

Found in between anatomical structures to reduce friction

Can become chronically

inflammedSlide18

Synovial Joint Stabilization

Muscle tension is important in limiting unwanted joint movementIf joint capsule is overstretched, reflex contraction of muscles in the area prevent overstretching (Hilton’s Law)Slide19

Synovial Joint Stabilization

Joints that are shallow and fit poorly must depend on capsular structures or muscles for supportSlide20

Synovial Joint Stabilization

Capsular and ligamentous tissue help to maintain anatomical integrity and structural alignment of synovial jointsSlide21

Synovial Joints

6 Types Synovial Joints:

Pivot joint

Gliding joint

Hinge joint

Condyloid

joint

Ball-and-Socket joint

Saddle jointSlide22

9-22

Types of Synovial Joints

Classified by the shapes of their articulating surfaces

Types of movement they allow

uniaxial if the bone moves in just one plane

biaxial if the bone

moves in two planes

multiaxial

(or

triaxial) if the bone moves in multiple planes Slide23

Uniaxial Joints

permits movement around one axis and one plane

allows only flexion and extension

examples – elbow, knee

knee joint

largest joint, most complex, most frequently injured

projection of one bone articulating with a ring/notch of another bone

examples - between vertebrate Slide24

Biaxial Joints

permits movement around two perpendicular axes and planes

Example

thumb

only saddle joint in the body

condyle fits into an elliptical socket

Example

between radius and carpals

ellipsoidalSlide25

Multiaxial Joints

permits movement around three or more axes and planes

most moveable joints

ball shaped head fits into concave depression

example - shoulder, hip

humeroscapular joint

most mobile joint

sacroiliac joint

hip joint

relatively flat articulating surface that allows gliding movement

example

between carpals

between tarsals

between vertebrateSlide26

Types of Joints

(ellipsoidal)Slide27

Pivot Joints

Rotation only (monaxial)

Figure 9–6 (3 of 6)Slide28

Pivot Joint

Radius, ulna

Freely moveable joint in which bone moves around central axis, creating rotational movementSlide29

Gliding Joints

Flattened or slightly curved facesLimited motion (nonaxial)

Figure 9–6 (1 of 6)Slide30

Gliding Joint

Allows bones to make sliding motion

Carpals and tarsals

Between vertebrae

and spineSlide31

Hinge Joints

Angular motion in a single plane (monaxial)

Figure 9–6 (2 of 6)Slide32

Hinge Joint

Allows only flexion and extension

Convex surface of one bone fits concave surface of other

Knee, elbow, phalangesSlide33

Condyloid/Ellipsoidal

JointsOval articular face within a depressionMotion in 2 planes (biaxial)

Figure 9–6 (4 of 6)Slide34

Condyloid

Joint



ellipsoidal joint

Bones can move about one another in many directions, but cannot rotate

Named for condyle-containing bone

Metacarpals, phalangesSlide35

Ball-and-Socket Joints

Round articular face in a depression (triaxial)

Figure 9–6 (6 of 6)Slide36

Ball & Socket Joint

One bone has rounded end that fits into concave cavity on another bone

Widest range of movement possible

Hips, shouldersSlide37

Saddle Joints

2 concave faces, straddled (biaxial)

Figure 9–6 (5 of 6)Slide38

Saddle Joint

Two bones have both concave and convex regions, shape of two bones complementing one another

Wide range of movement

Thumb = only saddle joint in bodySlide39

Movements of

DiarthrosesFlexion

Extension

Hyperextension

Abduction

Adduction

Rotation

Circumduction

Elevation

DepressionSupinationPronation

Plantar flexion

Dorsiflexion

Inversion

Eversion

Protraction

Retraction

Opposition Slide40

Flexion/ExtensionSlide41

Abduction/Adduction

Abduction—moving a body part away from midlineAdduction—moving a body part toward the midlineSlide42

Internal/External Rotation

Internal rotation—rotation towards the center of the body



medial rotation

External rotation—rotation away the center of the body



lateral rotationSlide43

Internal/External RotationSlide44

Hip Internal Rotation Slide45

Plantar Flexion/DorsiflexionSlide46

Supination/PronationSlide47

Elevation/DepressionSlide48

Inversion/EversionSlide49

What are the structures

and functions of the shoulder, elbow, hip, and knee

joints

…

And

what is the relationship between joint strength and mobility?Slide50

The Shoulder Joint

Also called the glenohumeral joint:

allows more motion than any other joint

is the least stable

supported by skeletal muscles, tendons, ligaments Slide51

Structure of the Shoulder Joint

Ball-and-socket diarthrosisBetween head of

humerus

and glenoid cavity of scapulaSlide52

ShoulderSlide53

Socket of the Shoulder Joint

Glenoid labrum:deepens socket of glenoid cavity fibrocartilage lining

extends past the boneSlide54

Processes of the Shoulder Joint

Acromion (clavicle) and coracoid process (scapula):project laterally, superior to the humerus

help stabilize the jointSlide55

Shoulder Ligaments

GlenohumeralCoracohumeralCoracoacromial

Coracoclavicular

Acromioclavicular

Slide56

Shoulder

GlenohumeralSternoclavicular

Acromioclavicular

Glenohumeral jointSlide57

Shoulder Muscles

Also called rotator cuff:supraspinatus

infraspinatus

subscapularis

teres

minor Slide58

The Elbow Joint

Figure 9–10Slide59

The Elbow Joint

A stable hinge jointWith articulations between humerus, radius, and ulnaSlide60

Articulations of the Elbow

Humeroulnar joint:largest articulation trochlea of

humerus

and trochlear notch of ulna

limited

movement

Humeroradial

joint:

smaller articulation

capitulum of humerus and head of radiusSlide61

Elbow

RadiohumeralHumeroulnar

RadioulnarSlide62

Elbow Muscle

Biceps brachii muscle: attached to radial tuberosity

controls elbow motion

Elbow Ligaments

Radial collateral

Annular

Ulnar collateral Slide63

H

and and wrist

The hand

and wrist comprise a number of different joint types: saddle, gliding and

condyloid

. Together, these joints give

the hands & fingers

a great deal of

mobilitySlide64

Wrist

RadiocarpalIntercarpalCarpalmetacarpalSlide65

Hand

IntermetacarpalMetacarpalphalangeal

Interphalangeal Slide66

Hip joint:

Coxal bone - femurSlide67

The Hip Joint

Also called coxal jointStrong ball-and-socket diarthrosis

Wide range of motionSlide68

Structures of the Hip Joint

Head of femur fits into itSocket of acetabulumWhich is extended by fibrocartilage acetabular labrumSlide69

Ligaments of the Hip Joint

IliofemoralPubofemoralIschiofemoral

Transverse acetabular

Ligamentum

teresSlide70

Sacroiliac jointSlide71

The Knee Joint

Figure 9–12a, bSlide72

Articulations of the Knee Joint

2 femur–tibia articulations:at medial and lateral condyles1 between patella and patellar surface of femurSlide73

Menisci of the Knee

Medial and lateral menisci:fibrocartilage pads at femur–tibia articulationscushion and stabilize joint

give lateral supportSlide74

Locking Knees

Standing with legs straight:“locks” knees by jamming lateral meniscus between tibia and femurSlide75

7 Ligaments of the Knee Joint

Patellar ligament (anterior)2 popliteal ligaments (posterior)Anterior and posterior cruciate ligaments (inside joint capsule)Tibial collateral ligament (medial)

Fibular collateral ligament (lateral)Slide76

TIBIOFEMORAL JOINT

TIBIOFIBULAR JOINT