Generalities

History of Anatomy

History of Anatomy

• Anatomy = the study of the structure and function of the body.

• Egypt (500 B.C.) = first formal study in anatomy• Earliest descriptions of anatomy in papyrus = 3000 B.C.• Hippocrates

first taught anatomy Greece (460 – 377 B.C.

founder of the science of anatomy

made the Hippocratic oath

Wrote a book “The nature of the human body is the beginning of Science”.

• Aristotle = ( 384-322 BC), first used the word “Anatome” Greek for cutting up or taking apart “Dissecare”

• Vesalius “ De Humani Corpori Fabrica” 1543. ( masterpiece)

• Hieronymus Fabricus (1537-1619) constructed the anatomical theater at in 1594 is a teacher of William Harvey, discovered the veinous valve.

• William Harvey (1628) “Exercitacio Anatomica De Motu Cordis et Sanguinis in Animalibus”. Discovered the blood circulation.

• 17th century, human dissection became an important feature in European medical schools.

• 18th and 19th centuries anatomist published impressive treatises and atlas with illustration

• Anatomy act of Britain was passed in Parliament 1832 legalizing the donation and receiving of human bodies for scientific studies.

Approaches to the study in Anatomy

• Regional anatomy – topographical anatomy• Systemic anatomy – study by systems, circulatory etc.• Clinical anatomy – emphasizes structures and functions

as they relate to the practice of medicine and other health sciences.

Regional anatomy

• Surface anatomy – study anatomy of the living body at rest and in action. The aim is to visualize structures that lie underneath the skin and are palpable.

• Physical examination – the clinical application of surface anatomy.

• Palpation – the clinical technique for examining living anatomy.

System

• Skeletal system

• Muscular system

• Integumentary system

• Nervous system

• Blood vascular system

• Lymphatics system

Anatomical Position

Normal anatomical position

• Normal anatomical position = the person is erect ( or lying supine as in erect) with the arms by the sides, palms facing forward, the legs together, and the feet directed forward.

Anatomical planes

• The midsagittal median plane is vertical between the anterior midline & the posterior midline dividing the body into left and right halves.

• Parasagittal ( paramedian) planes are parallel to the midsagittal plane.

• Coronal planes = are vertical and perpendicular to the midsagittal plane

• Midcoronal plane = (frontal) plane divides the body into anterior and posterior halves.

• Transverse (horizontal) plane = are mutually perpendicular to the midsagittal and coronal planes, dividing the bodyby cross sections.

• Axis = an intersection of any 2 mutually perpendicular planes.– Vertical axis = intersection between midsagittal

midcoronal plane– Anteroposterior axis = intersection between

trtansverse and sagittal planes– Bilateral axis = intersection between coronal and

transverse planes.

Anatomical Planes & References

• Frontal plane• Median plane• Sagittal plane• Parasagittal

plane

Anatomical positions

• Superficial• Superior• Inferior• Posterior • Anterior

(Ventral)• Caudal

(tail)

Anatomical adjectives

• Anterior/posterior – Anterior (ventral), towards the front aspect of the body– Posterior(dorsal), towards the back aspect of the body

• Proximal/distal– Proximal = close to the median or near the origin of a structure– Distal = away from the origin of a structure

• External/internal– External (superficial) = is close to the surface of the body.– Internal (deep) = is close to the center of the body.

• Superior/ inferior- Superior (cephalad, craniad, cephalic, rostral) towards the head– Inferior (caudad, caudal) towards the tail or feet.

• Medial / lateral– Median = in the midsagittal plane– Medial = towards the median.– Lateral = away from the median

• Central / peripheral– Central = toward the center of mass of body– Peripheral = away from the center of mass of the

body• Prone / supine

– Prone = ventral surface down.– Supine = ventral surface up

Anatomic movements• Flexion / extension = usually occurs in the midsagittal or parasagittal

plane.– Flexion = brings primitively ventral surfaces together.

• Plantar flexion = downward flexion of foot at the ankle joint.• Dorsiflexion = upward flexion (extension) of foot at ankle joint.• Radial deviation (flexion), abduction of the hand at the wrist joint.• Ulnar deviation (flexion), adduction of hand at the wrist joint.

– Extension = away from the ventral surface ( straightening the leg at the knee joint).

• Abduction / adduction = occurs in the midcoronal plane– Abduction (lateral flexion), movement away from the median plane.– Adduction , movement towards the median, towards the middle finger, or toward

the second toe.

• Medial rotation / lateral rotation =occurs about a line by the intersection of the coronal and or parasagittal plane sagittal)

– Medial rotation = movement of a ventral surface towards the median plane.– Lateral rotation = movement of a ventral surface away from the median plane

• Elevation / depression– Elevation, raises or moves a structure cephalad (shoulder shrug)– Depression, lowers or moves a structure caudally (directing the

eye downward)

• Protraction / retraction – Protraction = Moves a structure anterior (jutting out of the jaw)– Retraction = moves a structure towards the median (withdrawing a

protracted tongue into the oral cavity)

• Pronation/supination, refers to rotation of a specific region.– Pronation of the arm, a medial rotation so the palm face posteriorly.

– Supination of the arm = a lateral rotation so that the palm faces posteriorly.

Anatomical position

• Adduction• Abduction• Flexion• Extension• Rotation , medial

and lateral• Circumduction

• Inversion / eversion– Inversion of the foot, rotates the plantar surface inwards.– Eversion of the foot rotates the plantar surface laterally.

• Other terms– Intorsion / extorsion of the eye, rotation about an axis thru the

pupil.– Opposition / reposition of the thumb, a uniquely human

characteristics, refers to a rotation about a complex axis.– Circumduction = a combined movement, involving flexion/

extension with abduction/adduction.

• Supination• Pronation• Eversion• Inversion

Anatomical points, Skull

• Pterion – the union of frontal, parietal, sphenoid and temporal bones

• Occiput – from occipital,parietal,mastoid part of temporal

• Inion - Occipital protuberance • Foramen magnum – large opening at the base

of the skull• Lambda – the junction of the sagittal and

lambdoid sutures• Coronal sutures – separates frontal and parietal

bone

• Sagittal sutures – separates parietal bones• Lambdoid sutures – separates the parietal and

temporal bone from occipital bone• Bregma – intersection of sagittal and coronal

sutures.• Vertex – most superior point of the skull• Parietal foramen – found posteriorly near the

sagittal sutures, transmits emissary veins.

The skin

The skin• The largest organ in

the body.• Consist of:

– Epidermis – outer superficial layer, avascular

– Dermis- deeper connective tss.

– Subcutaneous tissue- loose tissue

– Skin ligaments retinacula cutis

– Deep fascia-dense• Functions:

– Protection– Heat regulation– Sensation

Dermis• Vascularized, nourishes the epidermis

• Contains:– Hair follicles– Arrector pili muscles, cause “goose bumps”– Sebaceous glands– Sweat glands– Collagen and elastic fibers- provides skin tone – Has tension lines of Langer

Appendages of the skin

• Hair

• Nail

• Glands (sebaceous & sweat glands)

Cleavage lines of the skin

Skeletal system

Composition of the skeletal system, Classification

• Axial skeleton– Head = Skull bones(hyoid and cervical)– Trunk = ribs, sternum, vertebrae, sacrum

• Appendicular skeleton– Bones of the upper and lower limbs– Pectoral bones (shoulder= clavicle, scapula)– Pelvic girdle (pelvis = ilium, pubis, sacrum,

coccyx)

Function

• Protection for vital structures• Support for the body• Mechanical basis for movements• Storage for salts ( calcium)• A continuous supply of new blood cells.

• Cartilage – resilient, semirigid connective tissue that forms parts of the skeleton where motion occurs. Has no capillary blood supply. Nutrition is thru long range diffusion.

• Bones:* compact bones = provide the strenght for weight bearing and the rigidity for attachment of muscles and ligaments.* spongy or cancellous bones = central mass containing: blood cells, blood platelets

• Axial skeleton

Skull - Cranium 8

- Face 14

- Auditory ossicles 6

Hyoid 1

Vertebrae 26

Sternum 1

Ribs 24

• Appendicular skeleton

Shoulder girdles

Clavicle 2

Scapula 2

Upper extremities

Humerus 2

Radius 2

Ulna 2

Carpals 16

Metacarpals 10

Phalanges 28

• Pelvic girdle

Hip bones 2• Lower extremities

Femur 2

Patella 2

Fibula 2

Tibia 2

Tarsals 14

Metatarsals 10

Phalanges 28

Total 206

Classification of bones (shape)

• Long bone = tubular,i.e., humerus

• Short bone = cuboidal, i.e.,tarsus & carpus

• Flat bones = protective.i.e., skull bones

• Irregular bones = various shapes and length.i.e, fascial bones

• Sesamoid bone = found where tendons cross the ends of long bones.i.e, patella

Accessory bones

• Developed when additional ossification center appears and form extra bones “ are also known as wormian bones or sutural bones”.

• Heterotopic bones = forms in soft tissue when they are not normally present.i.e., scars, riders bones in thighs of horse riders.

Bone markings:• Condyle – rounded articular area, “femur”

• Crest – ridge,i.e., iliac crest

• Epicondyle – eminence superior to a condyle

• Facet – smooth, flat, covered with cartilage, articulate with another bone

• Foramen – passage thru a bone

• Fossa – hollow or depressed area

• Groove – elongated depression or furrow

• Line – linear elevation• Malleolus – rounded process• Notch - indentation at the edge of bones• Protuberance – projection of bones• Spines – thorn like process• Spinous process – projecting spinelike

process• Trochanter – large blunt elevation• Tubercle – small raised eminence• Tuberosity – large rounded elevation

Trauma to bones• Atrophy = reduction in size due to unuse

• Absorbed = mandible in dental extraction

• Hypertrophy = increase in size to support weight for a long period of time.

• Fractures = a break in a normal bone.

• Reduction = to approximate the broken ends of a bone to its normal position.

• Callus formation = during bone healing, a collar of fibroblast surround an injured bone and secretes collagen for its healing.

• Greenstick fracture = incomplete fracture due to bending of a bone.

• Osteoporosis = reduction in the quantity of bone, lose elasticity, becomes brittle, fractures easily.

• Sternal puncture = examination of the bone marrow for hematological diseases.

Bone development

• Derived from mesenchyme thru:– Direct or intramembranous ossification

(membranous bone)= mesenchyme model formed during embryonic period, direct ossification begins in the fetal period.

– Endochondral or indirect ossification (cartilaginous bone) = cartilage models of the bone form from the mesenchyme during fetal period, later bone replaces the cartilage.

• Sutures = joints of two skull bones.

• Joints = an articulation.

• It is the place of union or junction between 2 or more bones or parts of the skeleton.

Classification of joints:

– Synovial = united by an articular capsule, characterized by a joint, covered by a cartilage, filled by fluids.

– Fibrous joints = united by fibrous tissue

– Plane joint = permit sliding or gliding moves in one plane(uniaxial)

– Hinge joint = moves in one plane (sagittal) around one axis. Permit flexion & extension only.

– Saddle joint = biaxial with opposing surface– Condyloid = biaxial and allow movement in 2

planes, sagittal/coronal– Ball & socket = multiaxial – Pivot = uniaxial and allow rotation