Bones Anisha Patel Nicole Lin Isabel Jackson Mariana Zenteno

Bone Classification Long Bones: forearm and thigh bone Short Bones: Bones in the wrists and ankles Flat Bones: Ribs and part of the skull Irregular Bones: Bones within the vertebrae Round Bones: Knee cap

Microscopic Structure Compact bones No gaps, osteon units make up the Haversian systems Spongy Bones: No central canals Osteocytes: Bone cells

Haversian system, or osteon – the structural unit of compact bone Lamella – weight-bearing, column-like matrix tubes composed mainly of collagen Haversian, or central canal – central channel containing blood vessels and nerves Volkmann’s canals – channels lying at right angles to the central canal, connecting blood and nerve supply of the periosteum to that of the Haversian canal Osteocytes – mature bone cells Lacunae – small cavities in bone that contain osteocytes Canaliculi – hairlike canals that connect lacunae to each other and the central canal Vocabulary

Cells within the Bones Osteoblasts – bone-forming cells Osteocytes – mature bone cells Osteoclasts – large cells that resorb or break down bone matrix Osteoid – unmineralized bone matrix composed of proteoglycans, glycoproteins, and collagen

Bone Development Osteogenesis and ossification – the process of bone tissue formation, which leads to: The formation of the bony skeleton in embryos Bone growth until early adulthood Bone thickness, remodeling, and repair

Classification of Breaks Bone fractures are classified by: The position of the bone ends after fracture The completeness of the break The orientation of the bone to the long axis Whether or not the bone ends penetrate the skin

Types of Fractures Greenstick – incomplete and the break occurs on the convex surface of the bend in the bone Fissured – an incomplete longitudinal break Comminuted – fracture is complete and fragments the bone Transverse – complete, and the break occurs at a right angle to the axis of the bone Oblique – at an angle other than a right angle to the axis of the bone Spiral – caused by twisting a bone excessively

Stages of a Healing Bone 1.Hematoma 2.Fibrocartilage callus forms 3.Granulation tissue (soft callus) forms a few days after the fracture 4.Capillaries grow into the tissue and phagocytic cells begin cleaning debris 5.Bony callus formation 6.Bone remodeling

JOINTS Fibrous Joints dense connective tissues connect bones between bones in close contact Cartilaginous Joints hyaline cartilage or fibrocartilage connect bones Synovial Joints most complex allow free movement synarthrotic immovable amphiarthrotic slightly movable diarthrotic freely movable

Fibrous Joints 3 Types Syndesmosis Fibrous sheet that connects the bones together amphiarthrotic Suture Thin layer of connective tissue that connects two bones together Synarthrotic Gomphosis Cone shaped Synarthrotic

Cartilaginous Joints 2 Types Synchondrosis Hayline cartilage Synarthrotic Symphysis Pad of fibrocartilage that lies between two bones Amphiarthrotic

Synovial Joints Diarthrotic Contains Synovial Fluid

Types of Synovial Joints Ball-and-Socket joint Hip or shoulder Condyloid Joint Joints in the Metacarpals and Phalanges

Gliding Joint Between Carpals and tarsals Hinge Joint Elbow

Pivot Joint Between the radius and Ulna Saddle Joint Between carpals and metacarpals

Joint Disorders Sprains damage to cartilage, ligaments, or tendons associated with joints forceful twisting of joint Bursitis inflammation of a bursa overuse of a joint Arthritis inflamed, swollen, painful joints Rheumatoid Arthritis Osteoarthritis Gout