Skeletal System

Bones The skeleton has two major parts: Axial skeleton are the bones of the head and trunk Appendicular skeleton are the bones of the pelvis shoulder girdle and limbs.

Bones Functions of the skeleton Aid in movement of the body Support and protect internal body organs Produce red and white blood cells Store minerals for the bodies usage.

Bones Ossification-process of bone formation. Ossification begins in week 8 of an embryos development. A baby is born with 270 bones and an adult has 206 bones A babies bones are soft and ossification continues and makes them hard and able to bear weight.

Bones Diaphysis-long bone containing a shaft. Epiphysis-end of long bone Medullary canal-center of the shaft where bone marrow is Spongy bone-breakdown of hard bone Periosteum-fibrous tissue covering the bone

Bones Bone growth starts from the center of the diaphysis and moves to the epiphyseal ends (end of the bones)

Bones Osteoblasts-bone cells involved in the formation of new bone. Osteoclasts-bone cells involved in the breakdown of old bone.

Bones When the epiephyseal cartilage is completely ossified growth stops. This is approximately 18 in females and 20-21 in males. Does this mean bone growth stops? Why or why not?

Bones-Types Long Bones-arms and legs Flat Bones-skull, ribs, sternum Irregular bones-vertebrae, coxyxx, facial bones. Short bones-cubelike bones of the tarsals/carpals Sesamoid bones- small bones that float in tendon

Bones Simple/closed fracture- break in bone that does not pierce skin Femur fracture

Bones Open/Compound Fracture- the fractured end penetrates the skin. Possible infection. tibia/fibula fracture

Bones Stress fracture-small incomplete break in the bone that results from overuse, weakness or biomechanical problems.

Bones Epiphyseal Plate Fracture-break in the bone at the growth plate. Typically in children 10-16, most often at wrist or ankle.

An avulsion fracture

Landmarks A landmark on a bone is a place where something attaches or changes direction.

Landmarks to know Fossa-hollow or depression Groove- ditchlike groove containing a tendon or blood vessel.

Landmarks to Know Epicondyle- prominence above or on a condyle Tubercle/tuberosity- rounded projection Spine- long thin projection.