Bone Lecture 2 PDF

Functions of the bones 1-Support the body and give the body its shape. 2- Skeletal muscles attached to the bone for movements. 3- Protect some important organs. For example, the skull protects the brain, the thoracic cage protects the heart and lungs, and the spine protects the spinal cord. 4-The bo...

Functions of the bones 1-Support the body and give the body its shape. 2- Skeletal muscles attached to the bone for movements. 3- Protect some important organs. For example, the skull protects the brain, the thoracic cage protects the heart and lungs, and the spine protects the spinal cord. 4-The bone marrow used for the production of blood cells. 5-The bone is considered as a store house of salt calcium and phosphorus. Classifications of bones 1-Regional classification: according to the position of bones (axial bones & appendicular bones) 2-Morphology classification: according to the shape of the bones 3-Structure classification. 4-Development classification. 1-Regional classification of human bones: 1- Axial bones: present in the midline of the body. 2- Appendicular bones: present in the periphery.  2-Morphological classification 1-Long bone. 2-Short bones. 3-Flat bones. 4-Irregular bones. 5-Pneumatic bones. 6-Sesamoid bones. 1-Long bone: a- Typical Long Bones: It is the bone having an elongated shaft (body or diaphysis), which extends between two expanded, smooth and articular ends (epiphyses). Examples: femur, tibia, humerus, radius b- Atypical long bones: It is known as the small long bones. Examples: Metacarpals, Metatarsals and Phalanges.  2-Short bones: The bones which are usually cubical, trapezoidal or scaphoidal in shape. Examples: carpal bones of hand and tarsal bones of foot. 3- Flat bones 4-Irregular bones 5-Pneumatic bones 6-Sesamoid bones 1- Compact bone Structural classification 2- Cancellous /spongy or trabecular bone  Developmental classification Cartilagenous bone e.g appendicular, vertebral column and thoracic cage  Developmental classification Membranous bones e.g bone of skull and face  Developmental classification Bones of mixed ossification membrano – cartilaginous bones  Structure of the living long bones - Body called diaphysis. - Each end is called epiphysis ( ‫ ) الكردوس‬formed of spongy bone. - It is covered with articular cartilage (‫)غضروف مفصلي‬ - The shaft is called the diaphysis ( ‫) عمد العظم‬ - The epiphysis is separated from the shaft by epiphyseal cartilage (‫)الغضروف الكردوسي‬ - The region of the shaft close to epiphyseal cartilage is called metaphysis (‫) الجمبز‬. - The shaft encloses medullary cavity ‫) )تجويف نخاعي‬ - The cavity is lined with a membrane called endosteum ‫) )غشاء العظم الداخلي‬ - The shaft is covered with periostum (‫) السحاق‬  Certain features of bones A- Elevations: ‫المرتفعات‬ Tuberosity , Trochanter, Tubercle, Epicondyle, Process Spine, Ridge, Crest and Line B- Depressions: (‫)المنخفضات‬ Fossa, Groove, sulcus and Notch C-Openings: (‫الثقوب‬ Foramen, Canal and Hiatus D-Articular surfaces: ( ‫) السطوح المفصلية‬ Head, Condyle, Trochlea and Facet Red & yellow bone marrow Blood supply of long bones  FUNCTIONS OF THE BONES 1- They give the body its shape. 2- The bones give the Attachment to the skeletal muscles for movements. 3- They protect some important organs. For example: - The skull protect the brain. - The thoracic cage protect the heart and lungs. - The spine protect the spinal cord. Dr. Marim Fayz 4- The bone marrow inside the bone is used for the production of blood cells. 5- The bone is considered as a store house of calcium and phosphorus. Dr. Marim Fayz