BIO2109 JOINTS

I. Structural classification

A.fibrous

1.no cavity

2.fibrous joints

3.movement depends on length of connective tissue

B.cartilaginous

1.bones joined with cartilage

2.no cavity

C.synovial

1.bones forming joint are separated by a fluid filled cavity

II. functional classification

D.synarthroses

2.immovable joints

E.amphiarthroses

1.slightly movable joints

F.diarthroses

1.freely movable joints

II.Examples of joints

A.sutures

1.fibrous

2.synarthroses

3.in skull

B.syndesmoses

1.fibrous

2. amphiarthrosis

2.connect bones to bones

a.with ligament

(1)connective tissue cord

b.with interosseous membrane

(1)sheet of connective tissue

3.tibiofibular joint

a.distal connection between tibia and fibula

4.longitidunal interosseus membrane

a.anterior tibiofibular ligament connects tibia and fibula

C.gomphoses

1.fibrous

2.holds tooth in socket

3.periodontal ligament

4.synarthroses

D.synchondroses

1.cartilaginous

2.synarthroses

3.bar of hyaline cartilage

4.at epiphyseal plates during growth

5. also at first rib and manubrium

E.symphyses

1.cartilaginous

2.amphiarthrotic

3.surfaces of bone covered with cartilage which fuses

4.intervertebral joints

5.pubic symphysis

III. Synovial Joints

A.all joints in limbs

B.characteristics of all synovial joints

1.articular cartilage on surface of joining bones

2.joint cavity

3.articular capsule

a.double layer

(1)fibrous cartilage

(a)outer continous with periosteum

(2)synovial membrane

(a)inside

(b)loose connective tissue

4.synovial fluid

a.lubricating fluid

b.similar to plasma

c.contains hyaluronic acid

(1)secreted by cells of synovial membrane

d.contained within articular cartilage

(1)squeezed out with pressure

5.reinforcing ligaments

C.characteristics of some synovial joints

1.fatty pads between 2 layers of capsule

2.menisci

a.fibrocartilage discs

3.bursae

a.flattened fibrous sacs

b.linned with synovial membrane

c.where tendons and muscle meet bone

at high friction points

4.tendons

a.to stabilize joint

b.extends from nearby muscle

5.tendon sheath

a.extended from bursae to wrap tendon

D.movements of synovial joints

a.gliding

(1)1 flat bone slips over another

(2)increase or decrease angle

b.extension

(1)hyperextension

(2)plantar flexion

(a)extension of ankle

(b)pointing toes

c.flexion

(1)dorsiflexion

(a)decrease ankle ankle

d.abduction

e.adduction

f.circumduction

g.rotation

h.supination

(1)radius and ulna

(2)in standard anatomical position

i.pronation

(1)palm posterior

(2)distal radius crosses ulna

j.inversion

(1)sole faced medially

k.eversion

(1)sole faced laterally

E.types of synovial joints

1.plane joints

a.nonaxial, gliding

b.intercarpals, tarsals

2.hinge joints

a.uniaxial

b.projection from 1 bone fits into fossa or groove of another bone

c.diarthroses

d.elbow

(1)capitulum and head of radius

(2)trochlea and ulna

(3)extension and flexion at elbow

(4)reinforced by ligaments and tendons from arm muscles

e.phalanges

f.knee

(1)largest and most complex

(2)extension,flexion, rotation

(3)3 joints , 1 cavity

(a)femoropatella joint

i)plane joint

(b)tibiofemoral joints (2)

i)lateral and medial joints

ii)femoral condyles and menisci of tibia

(4)partially enclosed joint cavity

(a)not closed anteriorly

i)3 ligaments run from patella to tibia

a)patella ligament

b)medial and lateral patella (5)many bursae

(6)reinforced with muscle tendons

(7)strong from quadriceps femoris

3.pivot joint

a.rounded projection of 1 bone fits into ring

b.atlas and axis

(1)rotation at atlas and axis

c.radioular

(1)proximal

(2)head of radius into ring-like ligament of ulna

4.condyloid joints

a.condyl into fossa

b.both oval

c.all angle motion

(1)flexion,extension

(2)abduction,adduction

(3)circumduction

d.biaxial

e.wrist

(1)radiocarpal

f.metacapophalangeal (knuckle)

5.saddle joints

a.more freedom

b.diarthroses

c.carpometacarpal joints of thumb

6.ball and socket

a.spherical head and concave socket of another

b.shoulder

(1)glenohumeral joint

(2)most freely movable in body

(3)glenoid cavity of scapula and head of humerus

(4)stabilize

(a)ligaments

i)coracoid to acromion

ii)coracoid to greater tubercle

(b)tendons

i)from biceps

a)most stabilizing

ii)rotator cuff

a)can be stretched

b)4 tendons encircle joint

c.hip

(1)coxal joint

(2)head of femur into acetabulum

(3) strong ligaments to reinforce

(a)ligamentum teres from head of femur

(4)tendons from hip and thigh muscles

(5)most stability provided by deep socket

IV.Homeostatic Imbalances of Joints

A.Sprains

1.stretch ligaments of joint (bone/bone)

B.cartilage tearing

1.tearing of knee menisci

2.avascular

a.hard to repair

3.arthroscopic surgery

a.removal of cartilage pieces

C.dislocation

1.joint out of socket

2.must be returned to proper place

D.bursitis

1.inflammation of bursae

2.stress or friction on the joint

E.tendonitis

1.inflammation of tendon sheaths

F.arthritis

1.inflammatory disease that damages joints

G.osteoarthritis

1.in articular cartilage

2.degenerative joint disease

a.from wear and tear of joints instead of inflammation

H.rheumatiod arthritis

1.autoimmune disease

I.Gouty arthritis

1.uric acid deposits in joint generally big toe (normally excreted)