Biomechanics of the Human Body -SkeletonPaytra Klein, Ben Student, Jen Franklin

Skeletal structure● Skeletal parts

o skeleton is built from bones and cartilage● Skeleton can be divided into 2 main parts

o Skeletal axis: spinal column, cranial bones, and rib cage

o Skeletal branches: pelvic girdle, shoulder girdle,arm, hand, leg, and foot bones

Skeletal functions● Its role is to support and move the body● Significantly protects the internal organs

o ex: cranium protects brain, ribs and sternum protect lungs and heart

● Skeleton forms shape of body and provides the muscles with connection points

● Plays important role in respiratory process by ventilating lungs

● Used to store mineral ions, such as calcium and phosphorus

Long bone● builds the limbs and have a cylindrical and elongated

structure. Include arm, femur, and finger bone

Short bone ● Structure is undefined but is generally cubic or

rectangular. These bones can be found in the wrist and the ankle.

Flat bone● Also called membranous bones, they are in the shape of a curved board

and they build cavity walls to protect the organs inside them. They are built of three layers - outer, inner and middle.

Irregular bones● Have a complex structure and lack uniform appearance.

Examples include vertebrae and jaw bones.

BONE INJURY

Fractures● a lesion in the bone, caused by a strong force on the bone

during a fall or accident. ● usually not life threatening, just painful, unless you tear a

blood vessel which can cause internal bleeding, or damages the nerves that control the vital organs such as the area of the spinal cord that controls respiration

Stress Fracture● injury caused by the erosion of the bone as a result of

constant pressure when a person is in motion and when the body fails to restore the bone and supply it with calcium because of constant use

● microscopic fractures form in the membrane that surronds the bone, which grow and become whole fractures if they are not treated

Osteoporosisa disease in which thins the bone tissue●bone density decreases due to a disorder of calcium metabolism in the body ●results:

o bone structure changeso bones are more easily fractured

●affected by the female hormone estrogen and therefore postmenopausal women are more susceptible to the disease ●Treatment

o taking estrogen ●also occurs in men

DAMAGE TO JOINTS

Sprain● caused by a sudden forceful wrench

(twist) or stretch of the joint that results in a torn ligament or tendon

Dislocation● occurs when a joint bone moves out of place.● following the dislocation, the joint loses its mobility, and

any attempt to move the joint causes pain.

lower back pain● many possible causes:

o disc and joint degeneration b/w the vertebrateo injury to muscles due to overuseo “herniated disc”:a disc b/w the vertebrae that contains gel

surrounded ● by a ring; if the ring tears, the gel may erupt and press on

nerves in the spinal cord (causing severe pain). some suffer from temporary pain and some have ongoing pain (a chronic condition)

Bone TissueBone is made up of bone tissue and connective tissue-the 2 types of bone tissue are…

- spongy bone tissue a sponge-like tissue, made from trabeculae, with

large cavities. Bone marrow tissue is found in these cavities. has osteons

- compact bone tissue: hard bone tissue which gives the bone its

strength. It is made up of osteons.

Bone building and resorption- Bone tissue is made from bone cells called osteocytes

- osteocytes are bone forming cells that are in the bone matrix (the hard part of the bone) compact bone tissue. they are arranged in cylindrical rings

- osteoclasts are large cells that nibble at and break down bone and responsible for bone resorption

- osteoblasts are large cells that form a closely packed sheet on the surface of the bone during both initial bone formation and later during bone remodeling

- the bone constantly goes through processes of construction and destruction where the much of the tissue that builds the bone is replaced

***bones heels very slowly because the materials needed for the existence of bone cells are transferred through osteocyte extensions.

cycle

Cartilage- cartilage is a dense flexible connective tissue

- the structure is similar to bone tissue but it doesn’t contain the minerals, calcium, and phosphate. Therefore, it is softer than bone

- it is formed from collagen, cartilage cells, and intercellular substance

Cartilage function- completion of bone growth

- this is between the ages of (18-20)- bones grow out of the cartilage, and in children it is found between the ends of long bones- when done growing the cartilage between bones goes away but cartilage still remains in some organs such as the nose, ears, joints and more

Why do engineers care about this?

-Engineers need to know what each structure in the human body does and how it works in order to replicate or replace it if needed-Must also know almost all the injuries that can occur to a body if he/she wants to construct Something that can fix the pain or damage.