Presentation on theme: "Department of Anatomy, Liaoning Medical College"— Presentation transcript:
1Department of Anatomy, Liaoning Medical College Human AnatomyDepartment of Anatomy,Liaoning Medical College
2No. 1 1. Introduction of Human Anatomy 2. Introduction of Osteology (Bony System)
3Introduction of Human Anatomy Definition: Human anatomy is the science which deals with the gross morphology and spacial interrelations of the structures of the body. The term “anatomy” is derived from the Greek words meaning “apart” and “to cut.”Significance: For medical students, human anatomy is the basic course of preclinical and clinical curriculum.Classification: Owing to different methods and purposes of study, human anatomy is classified into systematic anatomy, and regional anatomy.
4Ⅰ. Fields of anatomy (classification) Gross anatomy and microscopic anatomyThe study of anatomy involves examination of the general structures of the body (gross anatomy) as well as those structures that can be seen only with the aid of a microscope (microscopic anatomy).Microscopic anatomy includes the study of cells (cytology) and the study of tissues (histology). When anatomy is studied under the extremely high magnifications possible with the electron microscope, it is referred to as fine structure or ultrastructure.
5Regional anatomy and systematic anatomy: Gross anatomy can be studied by regions, such as the head, neck, thorax, abdomen, pelvis, or limbs. This approach, referred to as regional anatomy, is often used in dissection, in which all structures in a region are studied simultaneously. However, for our purposes the study of anatomy by organ systems that perform common functions (systemic anatomy) is most beneficial and this book uses that approach.
6Developmental anatomy: This subdivision of anatomy, focuses on the development of the body from the fertilized egg to the adult form. Developmental anatomy includes embryology, which is limited to prenatal development.Radiographic anatomy is particularly valuable in the diagnosis of disorders and injuries.
7Ⅱ. The general structure of the human body There are four structural levels in the body: cells, tissues, organs, and systems. Each level of body structure has specific functions that contribute not only to the structure itself but also to the general well-being of the entire body.Cell: The human body consists of innumerable cells.Tissue: Groups of cells become differentiated and built up various tissues of the body.The human body is composed of only four basic types of tissue: Epithelial tissue, Connective tissue, Muscular tissue, Nervous tissue.
8Organ: These tissues do not exist as isolated units, but rather in association one with another and in variable proportions and combinations, forming different organs and structures.System: A series of organs and structures can be arranged in a system according to their common function.locomotor system、alimentary system、respiratory system、urinary system、genital system、endocrine system、circulatory system(angiology) 、nervous system、sense organs
9Ⅲ. Anatomical position, Relational plane, Term of direction For the purpose of description, the human body is assumed to be in erect position, the “anatomical position”, with the face and toes directed forward, the heels and toes together, and upper limbs hanging by the side of the body with the palms of the hand facing forward.
112. Relational plane Sagittal plane Coronal plane Horizontal plane There are three kinds of relational planes.Sagittal planeCoronal planeHorizontal planeThese planes divide the body into left and right parts, anterior and posterior parts and superior and inferior parts, respectively.median sagittal plane that passes through the midline of body and divides the body into equal left and right parts.
123. Terms of directionThe terms of direction (position) commonly used in clinical practice and anatomy are illustrated in Fig. 1-1.PositionDescriptionAnteriorPosteriorIn front of another structureBehind another structureSuperiorInferiorAbove another structureBelow another structure
13PositionDescriptionSuperficialDeepCloser to the body surfaceFurther away from the body surfaceMedialLateralCloser to the median planeFurther away from the median planeInternalExternalNearer to the center of a hollow organ or body cavityFurther away from the center of a hollow organ or body cavityProximalDistalCloser to the trunk or originFurther away from the trunk or origin
14PART Ⅰ THE LOCOMOTOR SYSTEM Constitution: The locomotor system includes bones, joints and muscles.The general framework (skeleton) of the body is built up mainly of a series of bones together with articulation.Functions: The locomotor system not only provides the framework for the body, but also carries out the function of motion, support and protection.
17Section 1 introduction Bones in adult are 206 in number. Osteology is the study of bone and bones, the hard supporting tissue of the body.Bones in adult are 206 in number.Each living bone is an organ, it has proper shape and carries out certain functions. It is a hard and resilient organ, and is abundant in blood and nerve supply.Functions: It possesses the ability of reconstruction, repairing and regeneration. In fact, living bones are plastic tissues with organic and inorganic components.
18Ⅰ. The Shape and Classification of Bones Bones are different in shape because of the disparity of their functions.According to their shape, four kinds of bones are classified.Long bonesshort bonesflat bonesIrregular bones
20Ⅰ) Long bonesEach long bone consists of a shaft or body and two ends or extremities.Shaft: The shaft is a slender tube of compact bone tissue. There is a cavity in the inner of the shaft, known as medullary cavity: The cavity contains bone marrow in living bones.Extremity: The extremities are wider and known as epiphyses. The smooth surface of the end is called articular surface which is covered by articular cartilage.
21The shaft is connected with the epiphyses by cartilage known as epiphysial cartilage in young man. After the ossification of the epiphysial cartilages has finished in adult, the epiphyses fuse with metaphyses of the shaft, and become the epiphysial lines.Long bones are found in limbs, they act as the levers in locomotion.
23Ⅱ) Short BonesThe short bones are roughly in cuboid shape. They distribute in wrist and foot including the carpal and tarsal bones. These bones are composed of spongy bone with a thin layer of compact bone. The short bones can bear stronger pressure and play an important role of support.
24Ⅲ) Flat bonesThe flat bones consist of two plates of compact bone with spongy bone and marrow between them.In the cranial bones, the layer of compact bone are known as the plates of the skull; the outer plate is thick and tough, the inner plate is thin, dense and brittle. The intervening spongy substance is called the dioploё.They include the ribs, sternum, scapulae, and many bones of the skull.The functions of them are usually to protect the important organs such as the brain, the heart, the lungs, the liver and the spleen etc, or provide broad surfaces for muscular attachment.
25Ⅳ) Irregular BonesThe irregular bones are greatly varied in shape, carry out different functions, and can not be classified in the preceding groups.They include many of the cranial bones, the vertebrae, and the hip bones. Some cranial bones contain air-filled cavities or sinuses and are known as pneumatic bones, maxillae are the example.
26Ⅱ. The Structure of Bones Living bones consist of bony substance, periosteum and bone marrow, and are abundant in blood and nerve supply.
27Ⅰ) Bony SubstanceThe bony substance include compact or dense bone and cancelous or spongy bone.Compact bone: The compact bone forms the shaft of the long bone and the external layer of the epiphyses and out casing of other kinds of bone. It also forms the outer and the inner plates of the flat cranial bones.The compact bone is capable of resisting stresses and bending.
30Cancellous or spongy bone: The cancellous or spongy bone consists of a lot of trabeculae, which interweave with each other and arrange into an expanded meshwork like the sponge. The trabeculae run in directions suited to their function, and are arranged in line of the pressure and of tension, and in a X-ray photograph the pressure lines are seen to pass across joints from bone to bone.The spongy bone distributes in epiphysis and fills in the interior of all bones. The spongy bone in the cranial bones is known as the dioploё.
31Ⅱ) PeriosteumThe whole of the bone , except the articular part, is invested by a membranous covering of periosteum.It consists of two layers: an outer or fibrous membrane and an inner or vascular membrane lined with bone-forming cells, the osteoblasts. The function of these cells is most active during the period of the development, growth, reconstruction and repairing of the bones.
32The periosteum abounds with vessels, nerves and lymphatic vessels, and plays important role in the regeneration of the bones.So that, for the purpose of prevention of the bony necrosis or delayed healing, it is necessary to preserve the periosteum as much as possible when the operation on the bones is carried out.Endosteum: It lines the inner aspect of the medullary cavity.
34Ⅲ) Bone marrowThere are two kinds of bone marrow, red and yellow.Red marrow: The red marrow is capable of making blood cells. It consists of many developing blood cells of varied periods.Yellow marrow: The yellow marrow comprises a lot of fat.
35At birth, the cancellous bone and the medullary cavities of long bones are filled with red (blood-forming) marrow.By the sixth year, the red marrow in the medullary cavities are gradually replaced by yellow marrow. At about 18th year, red marrow is almost entirely replaced by yellow one in the bones of limbs, thereafter, it is confined to the axial skeleton (skull, vertebrae, ribs, sternum) and the hip bones, the upper ends of femur and humerus, and carries out continuously the function of blood-forming.The Red and white blood cells are formed in the red bone marrow.
36A puncture on iliac crest (or spinous process of lumbar vertebra, or sternum) to examine the marrow is a useful method to make a diagnosis of some blood diseases. In some types of anemia, the death rate of the red cells is high, the yellow marrow reverts to red in an endeavor to support the birth rate.
37Ⅲ. The Chemical Composition and Physical Properties of Bones Living bones are plastic tissues with organic and inorganic components. Bones have an organic framework of fibrous tissue and cells, among which inorganic salts are deposited.Organic material: The organic material (the main one is collagen) forms 30～40 per cent and gives the bones resilience and toughness;Inorganic material: The inorganic material, mineral salts, (the main one is calcium phosphate) 60～70 per cent of the dry weight of the bone and gives the bones hardness and rigidity and make them opaque to X-rays.
38The physical properties of the bones depend upon the chemical components which change with age. In infant and child, the organic components are relatively more than those in adult, so their bones are softer, and are easy to be deformed.But in the old people, the inorganic components are comparatively more, and bone fracture in the aged people is more often.
39A test can be taken to demonstrate the relationship between the chemical components and the physical properties of the bones. By submerging a bone in a mineral acid the salts are removed, but the organic material remains and still displays in detail the shape of the untreated bone. Such a specimen is flexible. For example, a decalcified fibula can be tied in a knot. By burning a bone with fire, the organic material is removed, this bone is more brittle than porcelain, crumble and fractured easily.
40Ⅳ. The Blood and Nerve Supply of Bones 1. The bones are furnished with an abundance of fine arterioles.(1) In the long bones, the arterial supply consists of:①periosteal twigs entering the shaft at many points;②twigs from articular arteries supplying the epiphyses;③the nutrient artery, which enters the medullary cavity through a nutrient foramen, supplying the shaft and the marrow.
41(2) The short bones receive numerous fine blood vessels from the periosteum. (3) Flat bones are supplied by numerous vessels which enter the bone at various points from the covering periosteum.(4) Large irregular bones like the scapula and hip bone receive both superficial vessels from periosteum and nutrient arteries.
422. Lymphatic vessels are abundant in the periosteum, and are present within the bone substances. 3. Numerous nerve fibers accompany the blood vessels of bones, they distribute widely to periosteum, bone substance and adventitia of the arteries.
43Ⅴ. The Functions of Bones The functions of bones can be summed up as follows:(1)Support: The skeleton acts as the framework of the body, giving support to the soft tissues and providing points of attachment for most of the body muscles.(2)Movement: Because many of the muscles attach to the skeleton, and many of the bones meet in movable joints, the skeleton plays an important role in determining the kind and extent of movement of which the body is capable.
44(3)Protection: The skeleton protects many of vital internal organs or viscera (e.g. brain and spinal cord, heart and lungs, liver and gallbladder) from injury.(4)Hemopoiesis (Blood-Cell Formation) Following birth, the red marrow in certain bones produces the blood cells (erythrocytes, granulocytes, monocytes and platelets) found in the circulatory system.(5)Mineral Reservoir: The bones are the storehouse of calcium and phosphorus and other minerals.