Hb 1 - Musculoskeletal

SPASM:

1- Support the soft tissues of the body in order that firm and erect posture can be maintained.

2- Protect delicate structures such as the heart.

3- Attachment for muscles (via tendons), allowing movement by muscle contraction.

4- Storage area for minerals such as calcium.

5- Make blood cells in the red marrow of long bones.

The axial skeleton and the appendicular skeleton

-Cranium

-Mandible

-Vertebrae

-Rib cage

All the bones in the arms and legs

26 individual bones, called vertebrae

1- Cervical or neck vertebrae: 7 of these vertebrae are found in the neck and the atlas and axial support the head.

2- Thoracic vertebrae: 12 vertebrae to which the 12 pairs of ribs are attached.

3- Lumbar: 5 broad vertebrae which support the lower back.

4- Sacrum: Below the lumbar spine is a bone called the sacrum, a series of fused vertebrae which is a part of the pelvis.

They are sandwiched with pads of cartilage. These are called intervertebral discs and they act as shock absorbers.

-Roughened where muscles are attached

-Smooth where joints are formed

-Grooved for nerves and blood vessels

1- Long bones. Role: Their lengths make good levers. Example: Femur

2- Short bones. Role: Adapted for strength and resisting large forces. Example: Carpals

3- Flat bones. Role: Their broad surface protects organs and provided extensive areas for muscle attachment. Example: Parietal bone (cranium)

4- Irregular bones. Role: Complex bones which cannot be put into any other categories. They have no particular shape or feature. Example: Vertebra.

5- Sesamoid bones. Role: Small oval bones set in tendons where there is larger than normal force. Example: Patella

1- Cartilage: Dense network of fiber's firmly embedded in a gel-like substance. This gives cartilage the versatility of being both tough and flexible.

2- Ligaments: Fibrous structures that connect bone to bone. They are tough and non elastic but pliable enough to permit movement at the joints.

3- Tendons: Like ligaments, they are made of non-elastic tissue, however, their role is to attach muscle to bone.

1- Fibrous joints: Bones held together by cartilage. Example: the spinal column

2- Cartilaginous joint: Parts of the skeleton held together by cartilage. Example: Ribcage

3- Synovial joints: Most common. Bones have a pad of cartilage at either end, this provides cushioning and protects the bones from rubbing together. The joint is sealed in a capsule containing synovial fluid which also helps prevent rubbing and allows smooth movement.

The bones are held in place at the joint by structures called ligaments. They keep the bones in place and prevent dislocation of the joint.

1- Ball and socket. It provides the greatest range of joint movement. The spherical head of one bone lodges in the spherical cavity of another. Examples: hip, shoulder

2- Hinge: Simplest and most common type. They allow movement in only one direction. Examples: elbow, knee.

3- Pivot: Allows two bones to move in a rotational motion by twisting against each other. Examples: neck.

4- Gliding: Permits mostly sideways movements, as well as movements in one direction. Examples: bones in wrists and ankles.

5- Condyloid: Permits a variety of movements in different planes; rotating movements, however, are not possible. Example: wrist.

6- Saddle joint: allows movement in two directions. Example: thumb.

1- Permit movement

2- Movement of body fluids - pump blood, peristalsis

3- Regulation of body fluids - bladder

4- Body stability

5- Heat production - 85%

1- Skeletal muscle, attached to the skeleton

2- Cardiac muscle, which makes up the heart

3- Smooth muscle, located in places like the gut

They make us able to move the skeleton. We have control over these muscles, therefore we say that muscle movement is voluntary.

To attach a muscle to bone

They are similar in that they are made of collagen and elastin. These two proteins are often found together in the body and give structure and rigidity, as well as stretch and elasticity.

Muscles are attached via the tendons to the skeleton at 2 points:

-The origin where there is little movement.

-The insertion where there is movement.

This is when teams of muscles work in opposition to each other: when one muscle is relaxed its opposing muscle contracts. Example: flexing the elbow.

It is found exclusively in the heart. It is a specialised type of muscle that allows the heart to beat rhythmically. We have no control over the contractions of heart muscle, therefore we say it's involuntary.

It is found in our digestive system. Organs like the stomach and the intestine are lined with smooth muscle.

The contraction of smooth muscle is called peristalsis and it is this type of contraction that moves food along the gut. The uterus is made up of smooth muscle and it is the powerful contractions that push the body out at birth.

Blood vessels also have a layer of smooth muscle and cause the vessels to dilate or constrict when the muscle relaxers or contracts respectively. This is how we regulate blood pressure.

We cannot control the contraction of smooth muscle, so it is said to be under involuntary control.