Lec 2 Bone and Cartilage Anatomy 1 PDF

Lec 2 Bone and cartilage Bones and cartilages  Contents functions of bones Classification of bones Structure of the living bones The shaft Blood supply cartilage Bones  Function 1. Contour the shape of the body 2. Attachments for skeletal muscles 3. Contain calcium and phosphoru...

Lec 2 Bone and cartilage Bones and cartilages  Contents functions of bones Classification of bones Structure of the living bones The shaft Blood supply cartilage Bones  Function 1. Contour the shape of the body 2. Attachments for skeletal muscles 3. Contain calcium and phosphorus, which helping in emergency 4. Bone marrow helps in formation of the blood cells and immune cells  5.protect vital organs as: 1. Brain in the skull 2. Heart in the thoracic cavity 3. Spinal cord in the vertebral canal Classifications of the bones 1. Regional classification 2. Structural classifications 3. Developmental classification 4. Morphological classification  1.Regional classification According to region of the bone Axail Appendecullar Centre of the body Limbs thoracic cage, Humerus Skull Femur Vertebral column  2.Developmental classification 1. Membranous bones Developed from connective tissue ,by intermembranous ossifiction Ex:: Cap of the skull Flat bones of the face  2.Cartilagenous bones Developed by the ossifiction of hyaline cartilage, by intra cartilagenous ossifiction EX:: Humerus 3.Bones of mixed ossifiction Developed partly by membrane and partly by cartilage EX::: Mandible Clavicle  Notes The articular cartilage of both bones is only fibrocartilage (2nd cartilage (  3.structural classification.1 Compact Bone: Hard and forms the outer layer (cortex( of all types of bones. It is well developed in the shaft of long bones. Cancellous (Spongy( Bone:.2 Made of a trabecular meshwork containing spaces filled with bone marrow. Found in the ends of long bones and within other types of bones.  4.Morphological classification 1. Long 2. Short 3. Flat 4. Irregular 5. Seasamoid 6. Pneumatic Long Bones a) Typical Long Bones: These are bones having an elongated shaft extending between two smooth articular ends (epiphyses(. The shaft (diaphysis( shows: A medullary cavity filled with bone marrow. A thick cortex of compact Example: Humerus b) Atypical Long Bones: These include: Long bones having only one epiphysis, known as small long bones. Example: Metacarpals and phalanges. Long bones without a medullary cavity. Example: Clavicle..Short Bones: Have a thin outer cortex and an inner structure of compact bone, supported by a layer of spongy bone. Examples: Wrist, ankle Flat Bones: Flattened or curved with two layers of compact bone separated by a layer of spongy bone. Examples: Skull, sternum, ribs. Irregular Bones: Bones that are neither long, short, nor flat, and are of cartilaginous types. Examples: Hip bone. Pneumatic Bones: 5 Bones containing air spaces. Example: Maxilla..6Sesamoid Bones: Bone nodules embedded in tendons, ligaments, or joint capsules. Examples: Patella, sesamoid bones around tendons in the body. N.B Patella is the largest seasamoid bone Structure of the "Living Bones:" Epiphysis: End of long bone. Diaphysis: Shaft of long bone Metaphysis Part of the diaphysis in close contact with the epiphyseal plate of cartilage  Epiphyseal Plate of Cartilage: In growing bones, the plate of hyaline cartilage between the epiphysis and metaphysis is responsible for growth in length. The epiphyseal plate of cartilage ossifies 22-15years after complete growth in length The Shaft (Diaphysis) is Formed of: A) Bone Cortex of Compact Bone B) Medullary Cavity: It is only found in long bones except for the clavicle and is filled with red or yellow bone marrow. It is the fatty, vascular tissue filling the medullary cavities in long bones and the meshes of spongy bones in adults C) Bone Marrow: It is the fatty, vascular tissue filling the medullary cavities in long bones and the meshes in spongy bone in adult Forms of bone marrow 1. Red bone marrow 2. Yellow bone marrow.1Red Bone Marrow: It is red marrow found in all bones, with active formation of blood cells. In long bones (e.g., humerus,( it is replaced by yellow marrow at puberty..2Yellow Bone Marrow: It has no role in the formation of blood cells.  Periosteum A fibrous membrane that covers the shaft of the bone. Structures attached to the periosteum: Joint capsule Tendons Muscles Ligaments Septa  Blood supply of the bones Bones are rich in blood supply for repair and regeneration. Nutrient, periosteal, metaphysical, epiphyseal arteries provide the blood supply. A) Nutrient Artery: A single artery enters through the nutrient canal. It supplies the inner two-thirds of the bone cortex, medullary cavity, and bone marrow. B) Periosteal Arteries: These supply the outer one-third of the bone cortex. C) Metaphyseal Arteries: They supply the metaphysis. D) Epiphyseal Arteries: These supply the epiphysis Cartilage Definition: Firm, rubber-like part of the skeleton. Features:.1Avascular (non-vascular(: Has no blood vessels, and its nourishment by diffusion from surrounding tissue fluids..2Insensitive: Contains no nerves..3Covered by fibrous membrane called perichondrium..4Calcification occurs when the cartilage is replaced by bone..5Radiolucent (black( in X-ray. Types of cartilage 1. Hyaline cartilage 2. White fibrocartilage 3. yellow elastic cartilage  1.Hyaline cartilage Poor in fibers.Bluish, translucent appearance. Examples: Embryonic cartilage. Articular cartilage of synovial joints (permanent(. Epiphyseal cartilage plate. Costal cartilage. Nasal cartilages, larynx, rings of trachea & bronchi. 2.White fibrocartilage Rich in white collagen fibers. White, opaque appearance. Strong and tough, usually found in places subjected to great pressure. Example: Intervertebral disc (I.V.D.) 3.Yellow elastic cartilage Rich in elastic fibers Elastic, yellow ,flexible Example External ear Epiglotis MCQ’s QUESTIONS  One of these bones doesnot have medullary cavity 1.clavicle 2.femur 3.Humerus  Responsible for growh of length at the bone ……. 1.bone marrow 2.epiphyseal plate 3.epiphysis 4.metaphysis Which of those bones not long ,short or flat 1.ribs 2.base of skull 3.maxilla