A & P test 2

Syndesmology

(arthrology) the study of articulations between bones

what are the articulations between bones generally

Fibrous tissue or cartilage

Simple Joint

two articulating bones

Ex: Shoulder Joint (Scapulo-humeral joint)

Compound Joint

two or more articulating bones

Ex: Stifle

Fibrous joint united by

fibrous tissue and has no joint cavity

Cartilaginous Joint united by

cartilage and little or no joint cavity

Synovial joint united by

joint capsule and is freely movable

Syndesmosis

joint that permits only slight movement

union of the shafts of the splint bones and cannon bone

Suture

between bones of the skull

Gomphosis

articulation of teeth in their sockets

Periodontium

collagenous tissues and fibroblasts that join the tooth to the socket

Cartilage

special type of connective tissue that is firmer than fibrous tissue but not as hard as bone

Synchondrosis

immovable joint

uniting medium is hyaline cartilage

union of diaphysis and epiphysis of an immature bone (growth plate)

Symphyses

United by flattened disks of fibrocartilage

between adjacent pelvic bones and bodies of adjacent vertebrae and sternebrae

can be replaced by bone with aging

What does a Synovial Joint contain

articular surfaces

articular cartilage

articular cavity

a joint capsule

ligaments

Articular surfaces

specialized layers of compact bone on surfaces that articulate with other bones

articular cartilage

layer of hyaline cartilage covering the articular surfaces

articular cavity

space between the adjacent bones of the joint surrounded by the joint capsule

often call potential space

Joint effusion

expansion of space due to inflammation with accumulation of fluid

What are the two layers of the joint capsule

Fibrous capsule (outer)

synovial membrane (inner)

Synovial joint

specialized connective tissue

extends from the edges of the articular cartilages of the adjacent bones but not covering the articular cartilage

secretes synovial fluid

Villi

(villi synoviales) may also project into the joint cavity

Synovial Fluid primary purposes

Lubrication of the joint

provision of a nutritional source for cartilage

removal of waste products from joint

Ligaments

connective tissue bands that extend from bone to bone

Intracapsular ligaments

found within joints and surrounded by the synovial membrane

Ex: cruciate ligaments of the stifle

Extracapsular ligaments

external to the joint capsule

Include: Collateral ligaments, Dorsal and palmar ligaments, Annular ligaments

Collateral Ligaments

medial and lateral aspects of joint

Dorsal and palmar ligaments

in front of and behind joint

Annular Ligaments

surround joint, fibers circle the joint

Menisci

fibrocartilage disks interposed between the surfaces of some joints

Functions of the mensicus

distributes compressive stress during weight bearing

augments joint stability

Truly intracapsular

not covered by synovial membrane

found in temporomandibular joint and stifle

Flexion

decreases angle between 2 bones making up the joint

Extension

increases the angle between 2 bones making up the joint

Hyperextension

increase angle between 2 bones to greater than 180 degrees

Adduction

movement toward median line

Abduction

movement away from median line

Rotation

twisting of a segment on its own segment or axis

Circumduction

movement of an extremity to outline a cone

Pronation

Turning dorsal surface up

Supination

turning dorsal surface down

Ginglymus (hinge) joint

move only in sagittal plane

Ex: Fetlock

Spheroid (ball & socket) joint

move in nearly any direction

Ex: hip

Saddle Joint

all movement except rotation

Ex: carpometacarpal joint in human thumb

Temporomandibular joint (TMJ)

between mandible and temporal bone of skull

Atlanto-occipital joint

between 1st cervical vertebrae (atlas) and occipital bone

Atlanto-axial joint

Between 1st and 2nd cervical vertebrae (atlas and axis)

Joints of the Appendicular Skeleton

Scapula, Shoulder, Elbow, Carpus, Fetlock, Pasturn, coffin joint

Sacroiliac Joint

Mobility progressively diminished as matures

Sacrum held tight to wing of the ilium by ligaments

May become more mobile at parturition

Can be separated by fall or trauma

Coxofemoral Joint

Best example of spheroid (ball & socket) joint

Head of femur fits into acetabulum of the os coxae

Movement in nearly all directions

Stifle Joint

Condyles of distal femur, patella, and proximal tibia

Femoral condyles separated from tibia by menisci

Stabilized by collateral and cruciate ligaments

Patella- sesamoid bone

Tarsus (hock)

composite joint

common calcaneal tendon (Achilles tendon)

Luxation= “dislocation”

Types of muscle tissue

Skeletal

smooth

cardiac

Skeletal Muscle

Responsible for voluntary movements of:

limbs

trunk

head

“meat” (domestic livestock)

Striped pattern

orderly arrangement

Smooth muscle

“involuntary” or “unstriated” muscle

cells do not have striation

Found in systems with autonomic functions

Smooth muscle is a major component of what organs

Digestive system

Urogenital system

Blood vessels

Cardiac Muscle

visible striations → type of striated muscle

contracts intrinsically (not voluntary control)

Restricted to heart

Rhythmic contraction = circulation of blood

Functions of muscular system

Really one function = Contraction

Relaxation is “Passive”

Smooth muscle functions

Stomach and intestine contract to mix and propel food along GIT

Blood vessels= control distribution of blood

Eye= adjust pupil and thickness of lens

Skin= piloerection (hair stand up)

Skeletal muscle functions

Permit locomotion to change position of bones

Respiration

Heat protection= shivering

Endomysium

between individual muscle fibers

Perimysium

sheath surrounding bundles

epimysium

around entire muscle

Abdominal muscle arrangement

parallel sheets

skeletal muscle

Sartorius muscles of medial thigh arrangement

Narrow bands

skeletal muscles

Biceps Brachii arrangement

Fusiform muscles

skeletal muscles

Fleshy attachments

appears to arise directly from bones

really attach to short tendon

attached to periosteum or penetrate bone surface for short distance

Tendons

fibrous bands of collagen connect muscles to bone

Most muscles attach to…

two bones

some to soft tissues (skin, etc)

More movable muscle attachment

insertion

Less movable muscle attachment

origin

Agonist

directly responsible for producing desired action

Antagonist

oppose that action; opposite the agonist

Synergist

oppose any undesired action of agonist

Cutaneous muscles

superficial between skin & deep fascia covering skeletal muscles

Attach to skin= responsible for skin movement

Sphincter

muscles encircle opening

Pyloric Sphincter

between stomach and small intestine

Synovial Structures Include…

Joint capsules

Bursae

Synovial (tendon) sheaths

Bursae

synovial sac between structures that rub together

Bicipital bursa

between biceps brachii tendon and humerous

Atlanto bursa

between ligamentum nuchae and atlas

Supraspinous Bursa

between ligamentum nuchae and T2

Superficial Bursae

between skin and ulna

Navicular bursa

between digital flexor tendon & navicular bone

Bursitis

inflammation of bursa (excessive fluid)

Synovial Sheath

resembles an elongated bursa between tendon and other tissue

edges reflect around tendon until they meet

Mesotendon

double fold of membrane where edges meet

vessels to/from tendon pass through this area

tenosynovitis

inflammation of sheath and tendon

low grade trauma

Muscle cell

muscle fiber

cell membrane

sarcolemma

cytoplasm

Sarcoplasm

Modified endoplasmic reticulum

Sarcoplasmic reticulum

Nervous System consists of..

Brain

Spinal Cord

Peripheral nerves

Central Nervous System (CNS)

Brain, Spinal Cord

Peripheral Nervous System

Peripheral Nerves

Functions of nervous system

initiate/ regulate movement of body

regulate secretions from glands

gather information from external and internal sources

Maintenace of appropriate conscious state

Stimulate behaviors for survival

Neuron

primary functional cell

generates electrical potential

“excitable”= action potential

Neurogial (glial)

most abundant cell

Structural, metabolic and protective support

Dendrites

transport electrical signals towards cell body

Axon

conduct electrical signals away from cell body