RT 211 MUSCULAR SYSTEM

RT 211 MUSCULAR SYSTEM BY YUL VICTORIA

Skeletal Muscles

• usually attached to bones

• striated, voluntary

Visceral muscles

• in the walls of some organs

• nonstriated, involuntary

Cardiac muscles

• in the heart, myocardium

• striated, involuntary

Skeletal Muscles

• the red lean meat of the body, make up almost half of the body weight.

• controlled by the cerebrum

Muscle fibers

muscle cells

Fibrils or Myofibrils

many fine threadlike structures

Fascia

a layer of connective tissue

Connective tissue

The attachment to bone is by __________, usually a tendon or aponeurosis, but sometimes directly to bone

Origin

of a muscle is its more fixed, less movable attachment, usually its proximal end.

Insertion

of a muscle is its more movable end, usually its distal end.

Tendon

sometimes called a sinew cord, or leader is a cordlike fibrous connective structure that extends from the end of a muscle to a bony attachment.

Aponeurosis

is a sheet of fibrous connective tissue that is often attached at one end to a muscle, often flat muscle and by the other end to a bone, cartilage, ligament or other muscle.

Tendon sheath

is a tunnel-like channel that surrounds a tendon

Tenosynovitis

Inflammation of a tendon sheath

Bursa

saclike structure lying between a muscle or tendon and an adjacent bony prominence over which the muscle tendon moves.

Bursitis

inflammation of a bursa and it is frequently very painful

Calcification

Deposition of calcium, may occur in a bursa or tendon sheath

Irritability

is the property of being able to respond to stimuli.

Conductivity

is the ability to conduct impulses from nerves, from electrical stimuli

Extensibility

is the facility or stretching. This occurs by a lengthening of the fibrils of each muscle fibers.

Elasticity

the ability to return to the original length following stretching

Contractility

is the ability to become shorter, and is due to a shortening with thickening of each fibril of each muscle fiber

Movement

Skeletal muscles collaborate with the skeletal system to generate voluntary movements

Posture and Stability

Muscles aid in sustaining posture and stabilizing joints.

Digestion

Smooth muscles in the digestive tract facilitate the movement of food through the digestive system

Heat Production

Muscle contractions generate heat, crucial for regulating body temperature

Respiration

The diaphragm and intercostal muscles are pivotal for breathing.

Circulation

Cardiac muscles propel blood, while smooth muscles in blood vessels regulate blood flow and pressure.

Muscle Tone

muscles do not completely relax when at rest, but remain partly contracted

Contraction

the main function of all muscles is to contract and cause movement of the body or a part of it.

Proximal

Muscle that cross a joint to insert into a bone and cause movement are located ______ to that joint.

Prime Movers

are muscles that initiate and carry out some movement

Antagonists

are muscles that perform some movement opposite to that caused by the prime movers.

Synergists

are muscles that act with the prime movers to accomplish some movement but prevent unwanted movement.

Fixation muscles

are those that hold the adjacent bones in a fixed position so that the prime movers may accomplish some certain movement.

Posture

the maintenance of the upright position of the body consists of a balanced contraction of some muscle groups and the partial relaxation of opposing groups.

Muscle spasm

is a contraction of muscles that may persist for a long period of time, without relaxation.

Paralysis of muscles

follows injury to, or destruction of, the nerves supplying that muscle.

Poliomyelitis

may attack cells in the spinal cord that supply motor nerves to skeletal muscles.

Infantile paralysis

Poliomyelitis is also known as ________

Diaphragm

Dome-shaped muscular partition that separates the thorax and abdomen.

4th ribs

The tops of the dome lie well above the costal margins and may reach the __________

Inspiration, Expiration

Following ________, they lie at a lower level than the following ________

lying down, upright

With the subject _______ the diaphragm lies at a higher level than when _____.

rise to the highest possible level

Air escaping from a hole in the wall of the stomach or intestine will ____________ in the abdomen

chest and abdomen

The diaphragm must be included in both ______ and _____ radiography

Pectoralis Major Muscle

Thick fan-shaped muscle that covers the upper anterior chest wall.

Psoas Major Muscle

Muscle lies lateral to the lumbar vertebrae in the posterior wall of the abdomen.

Intercostal muscles

Fill in the spaces between adjacent ribs, and their costal cartilages.

• Inguinal ligament

• Patellar ligament

• Ligamentumteres

• Calcaneal tendon

ENUMERATION: examples of ligaments and tendons

• Umbilical Area

• Inguinal Area

• Femoral Area

ENUMERATION: Weak abdominal area

• Aortic hiatus

• Esophageal hiatus

• Opening of the inferior vena cave

ENUMERATION: 3 LARGE OPENINGS IN THE DIAPHRAGM

• By Location

• By Shape

• By direction of fibers

• By Action

• Number of Parts

Enumeration: HOW MUSCLES ARE NAMED

• Movement

• Posture and Stability

• Digestion

• Heat Production

• Respiration

• Circulation

ENUMERATION: Functions of the muscular system