Dr. Martin's notes

Wednesday February 22, 2017


There are three groups of muscle
Smooth Muscle - (spindle shaped) found in the blood vessels and the intestinal tract. Most smooth muscle is involuntary.
Cardiac Muscle - (striated and branched) found in the heart only. Also involuntary
Skeletal muscle- (striated) Used for motion and movement. These muscles tire easily

Muscles have only one motion - Contraction (pulling)
They have an origin and an insertion and always pull toward the origin. The center of the muscle is called the BELLY
Muscles generally come in pairs. The main pulling muscle is the PRIME MOVER. The opposing muscle is the ANTAGONIST

Characteristics of muscles.

All muscles have to have:
Excitability - the ability to respond to a stimulus
Contractability - it reduces the distance between the parts of its contents
Extensibility - the ability to be stretched
Elasticity - the ability to return to the original length when relaxed

The contraction of muscle happens when a stimulus activates the muscle.
It then utilizes ATP to contract which produces energy + heat + byproducts (mostly lactic acid) + ADP
Too much lactic acid fatigues muscle and eventually will cause cramping

If a muscle is not utilized it will get smaller (atrophy). This is often called disuse atrophy.
If a muscle is built up, it hypertrophies.
If a muscle is hyperextended, it is a strain and causes pain, swelling and inflammation. Treat with RICE.

Protocol is to treat until the area is pain free or can be used, then rehabilitation.

The major injury to muscles is a strain or stretching beyond the normal elasticity.

Injury to joints and muscles include:

Tendonitis: an inflammatory process around the attachment of the muscle to bone
Bursitis: an inflammation around the joint capsule and bursa
Contusions: bruises
Myositis Ossificans: bone deposits in the muscle after bruising
Abrasions: scraping off of the upper skin surface (floor/rug burn)
Lacerations: cuts
Avulsions: Skin torn off
Puncture wounds: piercing the skin
Hematoma: a collection of blood under the skin

Click here to READ: The body’s response to injury