Skeletal System PDF

OBJECTIVES OF THE LECTURE: CLASSIFICATION OF THE SKELETAL SYSTEM 1) THE AXIAL SKELETON 2) THE APPENDICULAR SKELETON THE PECTORAL AND PELVIC GIRDLES TYPES OF BONES PARTS OF LONG BONE CLASSIFICATION OF THE SKELETAL SYSTEM THE HUMAN SKELETON IS CLASSIFIED INTO TWO PARTS: 1) AXIAL SKELE...

OBJECTIVES OF THE LECTURE: CLASSIFICATION OF THE SKELETAL SYSTEM 1) THE AXIAL SKELETON 2) THE APPENDICULAR SKELETON THE PECTORAL AND PELVIC GIRDLES TYPES OF BONES PARTS OF LONG BONE CLASSIFICATION OF THE SKELETAL SYSTEM THE HUMAN SKELETON IS CLASSIFIED INTO TWO PARTS: 1) AXIAL SKELETON: SKULL, VERTEBRAL COLUMN, RIBS AND STERNUM 2) APPENDICULAR SKELETON: BONES OF UPPER LIMB AND LOWER LIMB, PECTORAL GIRDLE AND PELVIC GIRDLE. THE SKULL WITH MANDIBLE -----------FORMS THE SKELETON OF THE HEAD THE SKULL WITHOUT MANDIBLE-----------IS CALLED CRANIUM  THE AXIAL SKELETON THE VERTEBRAL COLUMN CONSISTS OF SERIES OF VERTEBRAE THE BODIES OF THESE ARTICULATE WITH EACH OTHER THROUGH FIBROCARTILAGINOUS INTERVERTEBRAL DISCS. THE VERTEBRAL COLUMN IS DISTINGUISHED INTO 5 REGIONS: -- CERVICAL-------IS FORMED OF 7 VERTEBRAE -- THORACIC ------IS FORMED OF 12 VERTEBRAE -- LUMBAR ----IS FORMED OF 5 VERTEBRAE -- SACRAL -----IS FORMED OF 5 VERTEBRAE -- COCCYGEAL----IS FROMED OF 4 VERTEBRAE THE AXIAL SKELETON THE THORACIC RIBS ARE ATTACHED TO RIBS THE THORACIC VERTEBRAE + RIBS+ COSTAL CARTILAGES +STERNUM ------FORM THE THORACIC CAGE. THE SACRAL VERTEBRAE ARE UNITED TOGETHER FORMING SINGLE TRIANGULAR BONE ------- SACRUM. THE SACRUM +2 HIP BONES-------FROM THE PELVIS.  THE APPENDICULAR SKELETON THE SKELETON OF THE UPPER LIMB (UL) AND THE LOWER LIMB (LL) ARE SIMILAR IN THE GENERAL FEATURES. EACH CONSISTS OF THREE SEGMENTS: PROXIMAL , INTERMEDIATE AND DISTAL. THE PROXIMAL SEGMENT : CONSISTS OF 1 BONE - HUMERUS IN THE ARM OF UL - FEMUR IN THE THIGH OF LL THE INTERMEDIATE SEGMENT :CONSISTS OF 2 BONES - RADIUS AND ULNA IN THE FOREARM OF UL - TIBIA AND FIBULA IN THE LEG OF LL THE APPENDICULAR SKELETON THE DISTAL SEGMENT: CONSISTS OF 3 SETS OF BONES -- SMALL BONES: CARPAL BONES OF HAND , TARSAL BONES OF FOOT -- FIVE ELONGATED BONES : METACARPALS IN THE HAND, METATARSALS IN THE FOOT. -- PHALANGEAL BONES: 3 IN EACH FINGER OR TOE, EXCEPT THE THUMB AND BIG TOE CONSIST OF 2 PHALANGES. THE PECTORAL AND PELVIC GIRDLES THE PECTORAL GIRDLE (SHOULDER GIRDLE): CONSISTS OF SCAPULA AND CLAVICLE -IT ARTICULATES WITH THE AXIAL SKELETON ANTERIORLY AT THE STERNOCLAVICULAR JOINT THE PELVIC GIRDLE: CONSISTS OF 2 HIP BONES - IT ARTICULATES WITH THE AXIAL SKELETON POSTERIORLY AT THE SACROILIAC JOINT. TYPES OF BONES A. ACCORDING TO THE STRUCTURE: 1) COMPACT BONE: FORM THE OUTER HARD LAYER 2) CANCELLOUS BONE (SPONGY): FORM THE INNER DELICATE LAYER B. ACCORDING TO THE SHAPE: 1) LONG BONES: E.G. IN PROXIMAL AND INTERMEDIATE SEGMENTS OF LIMBS 2) SHORT BONES: E.G. CARPAL AND TARSAL BONES 3) FLAT BONES: E.G. SCAPULA AND BONES OF THE SKULL CAP TYPES OF BONES 4) IRREGULAR BONES: E.G. VERTEBRAE AND THE BONES OF THE SKULL BASE 5) PNEUMATIC BONES: E.G. SKULL BONES CONTAINING AIR-FILLED SPACES (SINUSES) C. ACCORDING TO THE DEVELOPMENT: 1) MEMEBRANOUS BONES: DEVELOPED IN DENSE MEMBRANES 2) CARTILAGINOUS BONES: DEVELOPED IN PREFORMED CARTILAGES  PARTS OF LONG BONE 2 ENDS AND ASHAFT EACH END -------IS CALLED EPIPHYSIS THE SHAFT --------IS CALLED DIAPHYSIS THE GROWING PART BETWEEN EPIPHYSIS AND DIAPHYSIS-- -----IS CALLED EPIPHYSEAL CARTILAGE PLATE EPIPHYSEAL CARTILAGE PLATE ------- IS THE SITE OF INCREASE OF BONE LENGTH AND THE SITE OF OSSIFICATION WHEN THE BONE LENGTH IS COMPLETED THE REGION OF THE SHAFT CLOSE TO THE EPIPHYSEAL CARTILAGE PLATE--------- IS CALLED METAPHYSIS  PARTS OF LONG BONE THE SHAFT IS COMPOSED OF COMPACT BONE AND CONTAINS A CAVITY ------ CALLED MEDULLARY CAVITY FILLED WITH BONE MARROW THE SHAFT IS COVERED WITH A FIBROUS MEMBRANE --------CALLED PERIOSTEUM THE EPIPHYSIS IS COMPOSED OF CANCELLOUS BONE AND COVERED WITH A LAYER OF HYALINE CARTILAGE PRACTICAL OBJECTIVES