The Skeletal System Sara Abad P.4
The Bones in the Body
Cranium- head Nasal Bone- nose
Maxilla- upper jaw bone Mandible- lower jaw bone Cervical- upper vertebrae
Thoracic/ Xiphoid Process- vertebrae
Lumbar- lower vertebrae
Coxal Bone- Pelvis
Scapula- shoulder blade
Clavicle- collarbone
Humerus- upper arm
Ulna- outer lower arm
Radius- inside of lower arm
Carpals- wrists
Metacarpals- hand
Phalanges- fingers and toes
Rib Cage- Ribs
Sacrum- pelvic wall
Coccyx- sacrum point
Pubic Bone- makes up pelvis
Schium- lower pelvis
Pubic Symphysis- joint in pelvis
Femur- thigh bone
Patella- kneecaps
Fibula- outer lower leg
Tibia- inner lower leg
Tarsals- ankle
Calcaneus- heel
Metatarsals- foot
Types of Bones
Long Bones- are longer than wide and often expand which provide strength, structure, and mobility with movement
Short Bones- are roughly cubed shaped which provide stability with little or no movement
Flat Bones- thin and curved bones which expand to protect and provide provision
Sesamoid Bones - special short bones forming tendons which modify pressure in the joints and alter directions
Irregular Bones- have complicated shapes which vary in function based on their structure and positions
Anatomy of the Long Bone
Long Bones contain Diaphysis, Proximal Epiphysis, Distal Epiphysis, and an Epipyseal Plate( disc of hyaline cartilage) on the outside. Long Bones contain Medullary Cavity(column containing yellow marrow) , Yellow Marrow, Compact Bone, Spongy Bone, Red Marrow(blood-forming tissue), Articular Cartilage, Epiphyseal Plate, Periosteum(covers external surface), Endosteum(covers internal bone surface), and Sharpey's Fiber on the inside.
Microscopic Anatomy of Compact Bone Tissue
Trabeculae aligns along lines of stress which help bone resist stress.
Contains irregularly arranged lamellae and osteocytes.
Nutrients diffuse through canaliculi from capillaries in endosteum from trabeculae.
Contains organic and inorganic substances to provide strength and durability without being brittle.
Bone Remodeling
Bone resorption and bone deposition by osteoblasts and osteoclasts completes bone remodeling.
Bone Resorption- giant osteoclasts break down bone matrix in order to start opoptosis. Bone Deposition- the osteoblasts deposit new bone matrix in the asteoid seam and start a clacification front to have calcified bone matrix.
Remodeling maintains calcium homeostasis and keeps the bone strong.
Bone Fracture Repair
Bone repair involves hematoma and callus formation for remodeling depending on the fracture: Nondisplaced Fracture, Displaced Fracture, Incomplete Fracture, Open (compound) Fracture, Closed( external) Fracture, Open (exernal) Reduction, and Closed (internal) Reducion.
1) Hematoma Forms: hemorrhaged blood clots at fracture site 2)Fibrocartillaginous Callus Form: cartilaginous matrix connect broken bone 3) Bony Callus Form: fibrocartilaginous calllus is replaced by immature bone 4)Bone Remodeling Occurs: compact bone is layered down
Joints
Joints are sites where 2 or more bones meet which give skeleton mobility and hold it together to play protective role in the process.
Fibrous Joints are joined together by collagen fibers of connective tissue: Sutures (between bones of skull), Syndesmoses (bones connected by ligaments, cords, bandfibrous) , Gomphoses (peg-in-socket)
Cartilaginous Joints are articulating bones united by cartilage: Sychondruses (bar/plate of hyaline cartilage= immobility) and Symphyses ( joint of fibrocartilage acting as shock absorber with limited movement)
Synovial Joints have articulating bones separated by fluid-containing joint cavities: Articular Cartilage, Joint(articular) Cavity, Articular Capsule, Synovial Fluid, Reinforcing Ligaments, Nerves and Blood Vessels
Movement Allowed by Synovial Joints Plane Joints, Hinge Joints, Pivet Joints, oJoints, and Ball-and-Socket Joints
Gliding Movements at the wrist, Angular Movements as Flexion, Hyperextension, Extension of the neck, vertebrae, shoulder, and knee, Opposition, Elevation and Depression, Protraction and Retraction, Inversion and Eversion, Dorsiflexion and Plantar Flexion, Pronation and Supination, Rotation of the head, neck, and lower limb, Abduction, and Adduction, Circumduction of the shoulder.
Joint Disorders
Joints are easily damaged through traumatic injury, inflammation conditions, and degenerative processes by friction and wear Common Joint Injuries: Cartilage Tears, Sprains, and Dislocations Inflammatory and Degenerative Conditions: Bursitis, Tendonitis, Lyme Disease, and different froms of Arthritis- Osteoarthritis, Rheumatoid Arthritis and Gooty Arthritis
Male VS. Female Pelvis
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The male and female pelvis have different characteristics such as that the female pelvis is wider so has longer distances between the iliac spines, bones of the male pelvis are thicker and heavier, the female sacrum is shorter, wider, and less curved, and the female pelvis is more curved or rounded.