Skeletal System & Bone Identification Anatomy & Physiology 2 Unit 2

The Role of Skeleton Bones are the organs of the skeletal system It provides support for the body It protects certain body organs (heart, lungs, etc) Bones also make blood cells for the body, this is called bone marrow Bone also stores calcium Bones also provide a place for your muscles to attach

Bones in the Skeleton There are 206 bones in the adult human body Babies and children have a few more bones than adults Bones have medical names, but also have common names

Some Bones in the Skeleton Upper Body Bones Cranium (skull) Mandible (jaw) Clavicle (collar bone) Scapula (shoulder) Sternum (breastbone) Humorous Ulna and radius Ribs Vertebrae (backbone) Phalanges (fingers) Lower Body Bones Ilium, Sacrum, Ischium (pelvis) Femur (thigh) Patella (kneecap) Fibula/Tibia (shins) Tarsals (ankle) Phalanges (toes

Axial Skeleton Skull Cranium Facial Frontal bone Parietal bone Temporal bone Occipital bone Ethmoid bone Facial Maxillae Palatine bones Zygomatic bones Lacrimal bones Nasal bones Vomer bones Mandible

Axial Skeleton Vertebral Column Bony Thorax Cervical (C1-C7) Thoracic (T1-T2) Lumbar (L1-L5) Sacrum Coccyx Bony Thorax Sternum Ribs True (1-7) False (8-12) Floating (11 & 12)

Appendiculuar Skeleton Shoulder Girdle Clavicle Scapulae Upper limbs Humerus Radius Ulna Hand Carpal Metacarpals Phalanges

Appendiculuar Skeleton Pelvic Girdle Ilium Ischium Pubis Lower limbs Femur Fibula Tibia Tarsal Calcaneus Talus Metatarsals Phalanges

Joints Joints Types: Plane joint Hinge joint Pivot joint Where bones come together Types: Plane joint Hinge joint Pivot joint Condyloid joint Saddle joint Ball-and-socket joint

Joints

Ligaments Ligaments Tough fibers that holds bone together, usually found at joints

Bone Growth & Structure Bones are made of cells (like all organs) Bone-forming cells are called osteoblasts As you grow your bone cells divide (using mitosis) to get longer and stronger There are two types of bone tissue Solid/Compact bone: hard and compact part of the bone Spongy bone: empty space in bones, usually fond near the ends of the bone, stores calcium

Bone Growth & Structure Types of bones: Long bones: longer than they are wide Short bones: generally cube-shaped Flat bones: thin, flat and usually curved Irregular bones: do not fit into any of the above categories

Fractures Comminuted – the bone breaks into many parts Compression – the bone is crushed Depressed – the fracture is pressed inward Impacted – the bone ends are forced into each other Spiral –occurs when excessive twisting force is applied Greenstick – incomplete break Compound – the bone breaks through the skin

Fractures Comminuted are more common in the aged, whose bones are brittle Depressed are typical skull fractures Impact are common with falls Greenstick are common in children whose bones are more flexible

Bone Fracture Repair A hematoma is formed (blood pocket) The break is splinted by fibrocartilage callus The bony callus is formed Bone remodeling occurs

Skeletal Disorders Osteoporosis Arthritis Scoliosis