Skeletal System

Skeletal System 206 bones Functions Supports body and provides shape Protects internal organs Movement and anchorage of muscles Mineral storage (Calcium and Phosphorus) Hemopoiesis (red marrow of the bone is the site of blood cell formation – red marrow is in long bones (epiphyses), sternum and ilia). Test question = provides mineral storage like calcium Test question = hemopoiesis – red marrow in long bones, sternum, & ilia produce RBC’s

Microscopic mature bone cells Bone formation Osteocytes = mature bone cell Osteo = bone Cyte = cell Microscopic mature bone cells 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Bone formation Ossification – new minerals deposit to form bone Begins at 8 weeks gestation Minerals replace previously formed cartilage. 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Bone formation Infants bones are soft and pliable because of incomplete ossification. As bones ossify, they become hard. Long bones grow in length and ossify from the center to the ends. 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Know the following…. Osteocytes = mature bone cells Osteoblasts = cells that actually form bone Osteoclasts = cells that tear down old bone 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Bone formation 1.02 Remember the structures of the skeletal system

Types of Bones Long bones Found in the arms and legs Diaphysis – shaft Epiphyses – ends Medullary cavity – center of shaft, filled with yellow bone marrow, which is mostly fatty cells, also cells that form white blood cells Endosteum- lines marrow cavity

Chewing with movable skull bone = mandible Occipital bone connects with spinal column

1.02 Remember the structures of the skeletal system Axial Skeleton Skull frontal view What are the structures of the frontal view of the skull. 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Axial Skeleton Skull lateral view What are the structures of the lateral view of the skull. 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Axial – skull, spinal column, ribs, sternum, hyoid (u-shaped bone in neck to which the tongue is attached) Appendicular – shoulder girdle, arms, pelvis, legs (126 bones total) 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Axial Skelton Hyoid Bone What is unique about the hyoid bone? 1.02 Remember the structures of the skeletal system

Vertebral Column

Spine – Vertebral Column Encloses the spinal cord Vertebrae – separated by pads of cartilage Intervertebral discs Cervical Vertebrae (7) Atlas – 1st cervical vertebrae Axis – 2nd cervical vertebrae Thoracic Vertebrae (12) Lumbar Vertebrae (5) Sacrum Coccyx

Appendicular Skeleton Shoulder girdle Clavicle, scapula, humerus 1.02 Remember the structures of the skeletal system

Appendicular skeleton Clavicle = collar bone Scapula = shoulder blade Humerus = upper arm Radius and ulna = lower arm (radius = thumb side) Carpals = wrist bones held together by ligaments

1.02 Remember the structures of the skeletal system Metacarpals = hand bones Phalanges = fingers Pelvis = 3 bones (ilium, ischium, and pubis) Femur = upper leg, longest and strongest bone in the body 1.02 Remember the structures of the skeletal system

Tibia and Fibula = lower leg (tibias touch – tibia is larger of the two bones) Sternum = breast bone Patella = kneecap Tarsal bones = ankle bones Calcaneus = heel bone Metatarsals = foot bones

Appendicular Skeleton Pelvis Pelvic girdle = ilium, ischium and pubis 1.02 Remember the structures of the skeletal system

Joints Joints are points of contact between 2 bones- classified according to movement: Diarthrosis – movable Amphiarthrosis – partially movable Synarthrosis – immovable Articular cartilage – covers joint surface Synovial Fluid – lubricating substance in joints                                              

1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Joints Ball and socket One bone has a ball at one end The other has a concave socket Allows for the greatest range of motion Ex: shoulder 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Joints Hinge joint Move in one direction 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Joints: Diarthroses Example of a hinge joint. Define uniaxial… permits movement in one axis only 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Joints Pivot joints Bones that rotate across each other 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Joints Gliding joint Bones with flat surfaces that slide across each other i.e. bones in ankle and hand 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Joints Amphiarthroses Partially movable joints 1.02 Remember the structures of the skeletal system

1.02 Remember the structures of the skeletal system Joints Synarthroses Immovable joints Connected by fibrous connective tissue 1.02 Remember the structures of the skeletal system

Bursa and Synovial Membrane Fluid-filled sac that contains the synovial membrane Lined by synovial membrane 1.02 Remember the structures of the skeletal system

Bursa and Synovial Membrane Capsule that encloses a joint Lines the bursa Contains synovial fluid 1.02 Remember the structures of the skeletal system

Types of movement Flexion is a position that is made possible by the joint angle decreasing.

Extension A movement of a joint in which one part of the body is moved away from another. i.e. going from sitting to standing

Abduction A motion that pulls a structure or part away the midline of the body. Adduction A motion that pulls a structure or part towards the midline of the body

Circumduction The circular or a more precise movement of a body part, such as a ball-and-socket joint or the eye.

Rotation A motion that occurs when a part turns on its axis. i.e. shaking your head “no”

Pronation A rotation of the forearm that moves the palm from an anterior-facing position to a posterior-facing position, or palm facing down.

Supination The opposite of pronation, the rotation of the forearm so that the palm faces anteriorly, or palm facing up.

Disorders of the Skeletal System Arthritis Arthritis = An inflammation of one or more joints. Osteoarthritis- degenerative, occurs with aging, 80% of Americans suffer, joints become enlarged and painful

Disorders of the Skeletal System Arthritis Rheumatoid arthritis = A chronic, autoimmune disease = joints become swollen and painful, joint deformities common 1.03 Understand the functions and disorders of the skeletal system

Rheumatoid arthritis                                                  Osteoarthritis

Disorders of the Skeletal System Gout Increase of uric acid deposited in joint cavity, mostly the great toe in men. 1.03 Understand the functions and disorders of the skeletal system

Disorders of the Skeletal System Osteoporosis- most of those affected are women. Mineral density of bone is reduced 35% – 65%. The loss of bone mass leaves the bone thinner, more porous and more prone to fracture. (soft like a sponge)

Disorders of the Skeletal System Osteoporosis How do you think osteoporosis treated?. Why is her height decreasing? 1.03 Understand the functions and disorders of the skeletal system

Disorders of the Skeletal System Rickets Found in children, caused by lack of vitamin D, bones become soft. Is this a common problem in the US? Why or why not? Normal legs

Disorders of the Skeletal System Abnormal spinal curvatures Kyphosis Lordosis Scoliosis swayback hunchback 1.03 Understand the functions and disorders of the skeletal system

Skeletal System Trauma Dislocation Separation of bones in a joint Subluxation = partial separation (dislocation) 1.03 Understand the functions and disorders of the skeletal system

Skeletal System Trauma Fracture- a break in a bone Treated by: Closed reduction- cast or splint applied Open reduction- surgical intervention with devices such as wired, metal plates or screws to hold bone in alignment Traction- pulling force used to hold the bone in place Used for fractures of long bones

Closed or simple Open or compound Greenstick Comminuted Spiral bone broken, broken ends don’t break skin Open or compound broken bone pierce the skin, can lead to infection Greenstick in children, bone bent and splintered but never completely separates Comminuted splintered or broken into many pieces Spiral bone twists, resulting in one or more breaks