Human AnatomyHuman Anatomy

Department of Anatomy,Department of Anatomy,Liaoning Medical CollegeLiaoning Medical College

No. 1No. 1

1. Introduction of Human Anatomy1. Introduction of Human Anatomy

2. Introduction of Osteology (Bony Syste2. Introduction of Osteology (Bony System)m)

Introduction of Human AnatomyIntroduction of Human Anatomy Definition:Definition: Human anatomy is the science which Human anatomy is the science which

deals with the gross morphology and spacial interdeals with the gross morphology and spacial interrelations of the structures of the body. The term relations of the structures of the body. The term “anatomy” is derived from the Greek words mean“anatomy” is derived from the Greek words meaning “apart” and “to cut.”ing “apart” and “to cut.”

Significance:Significance: For medical students, human anatoFor medical students, human anatomy is the basic course of preclinical and clinical cmy is the basic course of preclinical and clinical curriculum.urriculum.

Classification:Classification: Owing to different methods and pOwing to different methods and purposes of study, human anatomy is classified inturposes of study, human anatomy is classified into systematic anatomy, and regional anatomy.o systematic anatomy, and regional anatomy.

ⅠⅠ. . Fields of anatomy (classification)Fields of anatomy (classification) Gross anatomyGross anatomy and and microscopic anatomymicroscopic anatomy The study of anatomy involves examination of tThe study of anatomy involves examination of t

he general structures of the body (gross anatomy) ahe general structures of the body (gross anatomy) as well as those structures that can be seen only wits well as those structures that can be seen only with the aid of a microscope (microscopic anatomy). h the aid of a microscope (microscopic anatomy).

Microscopic anatomy includes the study of cellMicroscopic anatomy includes the study of cells (cytology) and the study of tissues (histology). Ws (cytology) and the study of tissues (histology). When anatomy is studied under the extremely high mhen anatomy is studied under the extremely high magnifications possible with the electron microscope,agnifications possible with the electron microscope, it is referred to as fine structure or ultrastructure. it is referred to as fine structure or ultrastructure.

Regional anatomyRegional anatomy and and systematic anatomy:systematic anatomy:

Gross anatomy can be studied by regions, such Gross anatomy can be studied by regions, such as the head, neck, thorax, abdomen, pelvis, or as the head, neck, thorax, abdomen, pelvis, or limbs. This approach, referred to as regional limbs. This approach, referred to as regional anatomy, is often used in dissection, in which anatomy, is often used in dissection, in which all structures in a region are studied all structures in a region are studied simultaneously. However, for our purposes the simultaneously. However, for our purposes the study of anatomy by organ systems that study of anatomy by organ systems that perform common functions (systemic perform common functions (systemic anatomy) is most beneficial and this book uses anatomy) is most beneficial and this book uses that approach.that approach.

Developmental anatomy: Developmental anatomy: This subdivision This subdivision of anatomy, focuses on the development of of anatomy, focuses on the development of the body from the fertilized egg to the the body from the fertilized egg to the adult form. Developmental anatomy adult form. Developmental anatomy includes embryology, which is limited to includes embryology, which is limited to prenatal development.prenatal development.

Radiographic anatomyRadiographic anatomy is particularly is particularly valuable in the diagnosis of disorders and valuable in the diagnosis of disorders and injuries.injuries.

ⅡⅡ. The general structure of the human body. The general structure of the human body There are four structural levels in the body: There are four structural levels in the body:

cells, tissues, organs, and systems. Each level of cells, tissues, organs, and systems. Each level of body structure has specific functions that body structure has specific functions that contribute not only to the structure itself but also contribute not only to the structure itself but also to the general well-being of the entire body.to the general well-being of the entire body.

Cell: The human body consists of innumerable Cell: The human body consists of innumerable cells.cells.

Tissue:Tissue: Groups of cells become differentiated and Groups of cells become differentiated and built up various tissues of the body.built up various tissues of the body.

The human body is composed of only four basic The human body is composed of only four basic types of tissue: Epithelial tissue, Connective types of tissue: Epithelial tissue, Connective tissue, Muscular tissue, Nervous tissue.tissue, Muscular tissue, Nervous tissue.

Organ: Organ: These tissues do not exist as isolated unitThese tissues do not exist as isolated units, but rather in association one with another ans, but rather in association one with another and in variable proportions and combinations, ford in variable proportions and combinations, forming different organs and structures.ming different organs and structures.

System: System: A series of organs and structures can be A series of organs and structures can be arranged in a system according to their commoarranged in a system according to their common function.n function.

locomotor systemlocomotor system 、、 alimentary systemalimentary system 、、respiratory systemrespiratory system 、、 urinary systemurinary system 、、 genitalgenital

　　systemsystem 、、 endocrine systemendocrine system 、、 circulatory systecirculatory syste

m m

(angiology) (angiology) 、、 nervous systemnervous system 、、 sense organssense organs

ⅢⅢ. Anatomical position, Relational . Anatomical position, Relational plane, Term of directionplane, Term of direction

1. Anatomical position1. Anatomical position

　　　　　　 For the purpose of description, the For the purpose of description, the human body is assumed to be in erect position, human body is assumed to be in erect position, the “anatomical position”, with the face and the “anatomical position”, with the face and toes directed forward, the heels and toes toes directed forward, the heels and toes together, and upper limbs hanging by the side together, and upper limbs hanging by the side of the body with the palms of the hand facing of the body with the palms of the hand facing forward.forward.

2. Relational plane2. Relational plane There are three kinds of relational planes.There are three kinds of relational planes.

Sagittal planeSagittal plane

Coronal planeCoronal plane

Horizontal planeHorizontal plane

These planes divide the body into left and right These planes divide the body into left and right parts, anterior and posterior parts and superior parts, anterior and posterior parts and superior and inferior parts, respectively. and inferior parts, respectively.

median sagittal planemedian sagittal plane that passes through the that passes through the midline of body and divides the body into equmidline of body and divides the body into equal left and right parts. al left and right parts.

3. Terms of direction3. Terms of direction

The terms of direction (position) commonly used in The terms of direction (position) commonly used in clinical practice and anatomy are illustrated in Fig. 1-clinical practice and anatomy are illustrated in Fig. 1-1.1.

PositionPosition DescriptionDescription

AnteriorAnterior

PosteriorPosterior

In front of another structureIn front of another structure

Behind another structureBehind another structure

SuperiorSuperior

InferiorInferior

Above another structureAbove another structure

Below another structureBelow another structure

PositionPosition DescriptionDescription

SuperficialSuperficial

Deep Deep

Closer to the body surfaceCloser to the body surface

Further away from the body surface Further away from the body surface

MedialMedial

Lateral Lateral

Closer to the median planeCloser to the median plane

Further away from the median plane Further away from the median plane

InternalInternal

External External

Nearer to the center of a hollow Nearer to the center of a hollow organ or body cavityorgan or body cavity

Further away from the center of a Further away from the center of a hollow organ or body cavity hollow organ or body cavity

ProximalProximal

Distal Distal

Closer to the trunk or originCloser to the trunk or origin

Further away from the trunk or origin Further away from the trunk or origin

PART THE LOCOMOTOR SYSTEMⅠPART THE LOCOMOTOR SYSTEMⅠ

Constitution:Constitution: The locomotor system includes boThe locomotor system includes bones, joints and muscles.nes, joints and muscles.

The general framework (skeleton) of the body is The general framework (skeleton) of the body is built up mainly of a series of bones together wibuilt up mainly of a series of bones together with articulation.th articulation.

Functions:Functions: The locomotor system not only proviThe locomotor system not only provides the framework for the body, but also carriedes the framework for the body, but also carries out the function of motion, support and protes out the function of motion, support and protection.ction.

Chapter 1 Osteology (BoChapter 1 Osteology (Bony System)ny System)

Section 1 introductionSection 1 introduction Osteology is the study of bone and bones, the hard Osteology is the study of bone and bones, the hard

supporting tissue of the body.supporting tissue of the body.

Bones in adult are 206 in number.Bones in adult are 206 in number.

Each living bone is an organ, it has proper shape Each living bone is an organ, it has proper shape and carries out certain functions. It is a hard and rand carries out certain functions. It is a hard and resilient organ, and is abundant in blood and nerve esilient organ, and is abundant in blood and nerve supply.supply.

Functions:Functions: It possesses the ability of reconstructio It possesses the ability of reconstruction, repairing and regeneration. In fact, living bonen, repairing and regeneration. In fact, living bones are plastic tissues with organic and inorganic cos are plastic tissues with organic and inorganic components.mponents.

ⅠⅠ. The Shape and Classification of Bones. The Shape and Classification of Bones

Bones are different in shape because of the Bones are different in shape because of the disparity of their functions.disparity of their functions.

According to their shape, four kinds of bones According to their shape, four kinds of bones are classified.are classified.

Long bonesLong bones short bonesshort bones flat bonesflat bones Irregular bonesIrregular bones

ⅠⅠ) Long bones) Long bones

Each long bone consists of a Each long bone consists of a shaft shaft or or body body and two and two ends or ends or extremitiesextremities. .

Shaft: The shaft is a slender tube of compact bone tiShaft: The shaft is a slender tube of compact bone tissue. There is a cavity in the inner of the shaft, knssue. There is a cavity in the inner of the shaft, known as own as medullary cavitymedullary cavity: The cavity contains bon: The cavity contains bone marrow in living bones.e marrow in living bones.

Extremity: The extremities are wider and known as Extremity: The extremities are wider and known as epiphysesepiphyses. The smooth surface of the end is calle. The smooth surface of the end is called d articular surfacearticular surface which is covered by articular c which is covered by articular cartilage.artilage.

The shaft is connected with the epiphyses by cartThe shaft is connected with the epiphyses by cartilage known as epiphysial cartilage in young milage known as epiphysial cartilage in young man. After the ossification of the epiphysial cartian. After the ossification of the epiphysial cartilages has finished in adult, the epiphyses fuse lages has finished in adult, the epiphyses fuse with metaphyses of the shaft, and become the with metaphyses of the shaft, and become the epiphysial linesepiphysial lines..

Long bones are found in limbs, they act as the leLong bones are found in limbs, they act as the levers in locomotion.vers in locomotion.

ⅡⅡ) Short Bones) Short Bones

The short bones are roughly in cuboid shape. TThe short bones are roughly in cuboid shape. They distribute in wrist and foot including the chey distribute in wrist and foot including the carpal and tarsal bones. These bones are compoarpal and tarsal bones. These bones are composed of spongy bone with a thin layer of compased of spongy bone with a thin layer of compact bone. The short bones can bear stronger presct bone. The short bones can bear stronger pressure and play an important role of support.sure and play an important role of support.

ⅢⅢ) Flat bones) Flat bonesThe flat bones consist of two plates of compact bone with sThe flat bones consist of two plates of compact bone with s

pongy bone and marrow between them.pongy bone and marrow between them.

In the cranial bones, the layer of compact bone are known aIn the cranial bones, the layer of compact bone are known as the plates of the skull; the outer plate is thick and tough,s the plates of the skull; the outer plate is thick and tough, the inner plate is thin, dense and brittle. The intervening the inner plate is thin, dense and brittle. The intervening spongy substance is called the spongy substance is called the dioploёdioploё. .

They include the ribs, sternum, scapulae, and many bones oThey include the ribs, sternum, scapulae, and many bones of the skull.f the skull.

The functions of them are usually to protect the important oThe functions of them are usually to protect the important organs such as the brain, the heart, the lungs, the liver and rgans such as the brain, the heart, the lungs, the liver and the spleen etc, or provide broad surfaces for muscular attthe spleen etc, or provide broad surfaces for muscular attachment.achment.

ⅣⅣ) Irregular Bones) Irregular Bones

The irregular bones are greatly varied in The irregular bones are greatly varied in shape, carry out different functions, and shape, carry out different functions, and can not be classified in the preceding can not be classified in the preceding groups.groups.

They include many of the cranial bones, the They include many of the cranial bones, the vertebrae, and the hip bones. Some vertebrae, and the hip bones. Some cranial bones contain air-filled cavities or cranial bones contain air-filled cavities or sinuses and are known as pneumatic sinuses and are known as pneumatic bones, maxillae are the example.bones, maxillae are the example.

ⅡⅡ. The Structure of Bones. The Structure of Bones

Living bones consist of bony substance,Living bones consist of bony substance, periosteum and bone marrow, and are abun periosteum and bone marrow, and are abundant in blood and nerve supply.dant in blood and nerve supply.

ⅠⅠ) Bony Substance) Bony Substance

The bony substance include compact or dense boThe bony substance include compact or dense bone and cancelous or spongy bone. ne and cancelous or spongy bone.

Compact bone:Compact bone: The compact bone forms the sha The compact bone forms the shaft of the long bone and the external layer of the ft of the long bone and the external layer of the epiphyses and out casing of other kinds of bonepiphyses and out casing of other kinds of bone. It also forms the outer and the inner plates oe. It also forms the outer and the inner plates of the flat cranial bones.f the flat cranial bones.

The compact bone is capable of resisting stresses The compact bone is capable of resisting stresses and bending.and bending.

Cancellous or spongy bone: Cancellous or spongy bone: The The cancellouscancellous or or spongy bonespongy bone consists of a lot consists of a lot

of trabeculae, which interweave with each otheof trabeculae, which interweave with each other and arrange into an expanded meshwork like r and arrange into an expanded meshwork like the sponge. The the sponge. The trabeculaetrabeculae run in directions su run in directions suited to their function, and are arranged in line oited to their function, and are arranged in line of the pressure and of tension, and in a X-ray phf the pressure and of tension, and in a X-ray photograph the pressure lines are seen to pass acrotograph the pressure lines are seen to pass acrossoss joints from bone to bone.joints from bone to bone.

The spongy bone distributes in epiphysis and fillThe spongy bone distributes in epiphysis and fills in the interior of all bones. The spongy bone s in the interior of all bones. The spongy bone in the cranial bones is known as the dioploё. in the cranial bones is known as the dioploё.

ⅡⅡ) Periosteum) Periosteum

The whole of the bone , except the articular paThe whole of the bone , except the articular part, is invested by a membranous covering of periort, is invested by a membranous covering of periosteum.steum.

It consists of two layers: an outer or fibrous mIt consists of two layers: an outer or fibrous membrane and an inner or vascular membrane lined embrane and an inner or vascular membrane lined with bone-forming cells, the osteoblasts. The funcwith bone-forming cells, the osteoblasts. The function of these cells is most active during the period tion of these cells is most active during the period of the development, growth, reconstruction and rof the development, growth, reconstruction and repairing of the bones.epairing of the bones.

The periosteum abounds with vessels, nerves anThe periosteum abounds with vessels, nerves and lymphatic vessels, and plays important role id lymphatic vessels, and plays important role in the regeneration of the bones.n the regeneration of the bones.

So that, for the purpose of prevention of the bonSo that, for the purpose of prevention of the bony necrosis or delayed healing, it is necessary to y necrosis or delayed healing, it is necessary to preserve the periosteum as much as possible wpreserve the periosteum as much as possible when the operation on the bones is carried out.hen the operation on the bones is carried out.

EndosteumEndosteum: It lines the inner aspect of the medul: It lines the inner aspect of the medullary cavity.lary cavity.

ⅢⅢ) Bone marrow) Bone marrow

There are two kinds of bone marrow, red and There are two kinds of bone marrow, red and yellow.yellow.

Red marrow: The Red marrow: The red marrowred marrow is capable of is capable of making blood cells. It consists of many making blood cells. It consists of many developing blood cells of varied periods.developing blood cells of varied periods.

Yellow marrow: The Yellow marrow: The yellow marrowyellow marrow comprises a comprises a lot of fat.lot of fat.

At birth, the cancellous bone and the medullary At birth, the cancellous bone and the medullary cavities of long bones are filled with red (blood-forcavities of long bones are filled with red (blood-forming) marrow.By the sixth year, the red marrow in ming) marrow.By the sixth year, the red marrow in the medullary cavities are gradually replaced by yethe medullary cavities are gradually replaced by yellow marrow. At about 18th year, red marrow is alllow marrow. At about 18th year, red marrow is almost entirely replaced by yellow one in the bones most entirely replaced by yellow one in the bones of limbs, thereafter, it is confined to the axial skeleof limbs, thereafter, it is confined to the axial skeleton (skull, vertebrae, ribs, sternum) and the hip bonton (skull, vertebrae, ribs, sternum) and the hip bones, the upper ends of femur and humerus, and carries, the upper ends of femur and humerus, and carries out continuously the function of blood-forming.es out continuously the function of blood-forming.

The Red and white blood cells are formed in thThe Red and white blood cells are formed in the red bone marrow.e red bone marrow.

A puncture on iliac crest (or spinous pA puncture on iliac crest (or spinous process of lumbar vertebra, or sternum) to rocess of lumbar vertebra, or sternum) to examine the marrow is a useful method to examine the marrow is a useful method to make a diagnosis of some blood diseases. make a diagnosis of some blood diseases. In some types of anemia, the death rate of In some types of anemia, the death rate of the red cells is high, the yellow marrow rethe red cells is high, the yellow marrow reverts to red in an endeavor to support the verts to red in an endeavor to support the birth rate.birth rate.

ⅢⅢ. The Chemical Composition and . The Chemical Composition and Physical Properties of BonesPhysical Properties of Bones

Living bones are plastic tissues with organic and Living bones are plastic tissues with organic and inorganic components. Bones have an organic inorganic components. Bones have an organic framework of fibrous tissue and cells, among framework of fibrous tissue and cells, among which inorganic salts are deposited.which inorganic salts are deposited.

Organic materialOrganic material: The organic material (the main : The organic material (the main one is collagen) forms 30one is collagen) forms 30 ～～ 40 per cent and gives 40 per cent and gives the bones resilience and toughness;the bones resilience and toughness;

Inorganic material: Inorganic material: The inorganic material, mineral The inorganic material, mineral salts, (the main one is calcium phosphate) 60salts, (the main one is calcium phosphate) 60 ～～70 per cent of the dry weight of the bone and 70 per cent of the dry weight of the bone and gives the bones hardness and rigidity and make gives the bones hardness and rigidity and make them opaque to X-rays.them opaque to X-rays.

The physical properties of the bones The physical properties of the bones depend upon the chemical components which depend upon the chemical components which change with age. change with age.

In infant and child, the organic In infant and child, the organic components are relatively more than those in components are relatively more than those in adult, so their bones are softer, and are easy to adult, so their bones are softer, and are easy to be deformed.be deformed.

But in the old people, the inorganic But in the old people, the inorganic components are comparatively more, and bone components are comparatively more, and bone fracture in the aged people is more often.fracture in the aged people is more often.

A test can be taken to demonstrate the A test can be taken to demonstrate the relationship between the chemical components relationship between the chemical components and the physical properties of the bones. By and the physical properties of the bones. By submerging a bone in a mineral acid the salts submerging a bone in a mineral acid the salts are removed, but the organic material remains are removed, but the organic material remains and still displays in detail the shape of the and still displays in detail the shape of the untreated bone. Such a specimen is flexible. untreated bone. Such a specimen is flexible. For example, a decalcified fibula can be tied in For example, a decalcified fibula can be tied in a knot. By burning a bone with fire, the a knot. By burning a bone with fire, the organic material is removed, this bone is more organic material is removed, this bone is more brittle than porcelain, crumble and fractured brittle than porcelain, crumble and fractured easily.easily.

ⅣⅣ. The Blood and Nerve Supply of Bones. The Blood and Nerve Supply of Bones

1. The bones are furnished with an abundance o1. The bones are furnished with an abundance of fine arterioles.f fine arterioles.

(1) In the long bones, the arterial supply consis(1) In the long bones, the arterial supply consists of: ts of:

① ①periosteal twigs entering the shaft at many pperiosteal twigs entering the shaft at many points;oints;

② ②twigs from articular arteries supplying the etwigs from articular arteries supplying the epiphyses;piphyses;

③ ③the nutrient artery, which enters the medullathe nutrient artery, which enters the medullary cavity through a nutrient foramen, supplyinry cavity through a nutrient foramen, supplying the shaft and the marrow.g the shaft and the marrow.

(2) The short bones receive numerous fine bloo(2) The short bones receive numerous fine blood vessels from the periosteum.d vessels from the periosteum.

(3) Flat bones are supplied by numerous vessels (3) Flat bones are supplied by numerous vessels which enter the bone at various points from the which enter the bone at various points from the covering periosteum.covering periosteum.

(4) Large irregular bones like the scapula and hi(4) Large irregular bones like the scapula and hip bone receive both superficial vessels from pep bone receive both superficial vessels from periosteum and nutrient arteries.riosteum and nutrient arteries.

2. Lymphatic vessels are abundant in the perios2. Lymphatic vessels are abundant in the periosteum, and are present within the bone substancteum, and are present within the bone substances.es.

3. Numerous nerve fibers accompany the blood 3. Numerous nerve fibers accompany the blood vessels of bones, they distribute widely to perivessels of bones, they distribute widely to periosteum, bone substance and adventitia of the aosteum, bone substance and adventitia of the arteries.rteries.

ⅤⅤ. The . The FunctionsFunctions of Bones of Bones The functions of bones can be summed up as The functions of bones can be summed up as

follows:follows: (1)Support: The skeleton acts as the (1)Support: The skeleton acts as the

framework of the body, giving support to the framework of the body, giving support to the soft tissues and providing points of attachment soft tissues and providing points of attachment for most of the body muscles.for most of the body muscles.

(2)Movement: Because many of the muscles (2)Movement: Because many of the muscles attach to the skeleton, and many of the bones attach to the skeleton, and many of the bones meet in movable joints, the skeleton plays an meet in movable joints, the skeleton plays an important role in determining the kind and important role in determining the kind and extent of movement of which the body is extent of movement of which the body is capable.capable.

(3)Protection: The skeleton protects many of vit(3)Protection: The skeleton protects many of vital internal organs or viscera (e.g. brain and spial internal organs or viscera (e.g. brain and spinal cord, heart and lungs, liver and gallbladdenal cord, heart and lungs, liver and gallbladder) from injury. r) from injury.

(4)Hemopoiesis (Blood-Cell Formation) Follow(4)Hemopoiesis (Blood-Cell Formation) Following birth, the red marrow in certain bones proding birth, the red marrow in certain bones produces the blood cells (erythrocytes, granulocyteuces the blood cells (erythrocytes, granulocytes, monocytes and platelets) found in the circulas, monocytes and platelets) found in the circulatory system.tory system.

(5)Mineral Reservoir: The bones are the storeh(5)Mineral Reservoir: The bones are the storehouse of calcium and phosphorus and other minouse of calcium and phosphorus and other minerals.erals.