CH. 4: Muscular System

Musculoskeletal System

Refers to the muscular and skeletal systems jointly, provides the body with form, support, stability, and the ability to move

The body has more than ___ muscles.

600 which make up about 40-45% of the body’s weight

Fascia

Thin connective tissue that covers muscles and separates them

Myofascial

Pertaining to muscle tissue and fascia

Muscle Fibers

Long, slender cells that make up muscles

Tendons

Connect muscle to bones

Patellar Tendon

Attaches muscles to the bottom of the patella

Achilles Tendon

Attaches gastrocnemius muscle (major muscle of the calf) to the calcaneus (heel) bone

Skeletal Muscles

Voluntary, striated muscles that are attached to the bones

Smooth Muscles

Involuntary, unstriated, visceral muscles that serve as walls of internal organs

Myocardial Muscle

Involuntary, unstriated, visceral muscle which serve as walls of the heart

Muscle Innervation

Nervous input that causes an action within a muscle or an organs

Neuromuscular

Pertaining to the relationship between a nerve and muscle

Antagonistic Muscle Pairs

Refers to working in opposition to each other so when one muscle of the pair contracts, the opposite muscle of the pair relaxes

Abduction

Movement of a limb (arm or leg) away from the midline of the body

Adduction

Movement of a limb (arm of leg) toward the midline of the body

Flexion

Decreasing the angle between two bones: bending a limb at a joint

Extension

Increasing the angle between two bones: straightening out a limb

Hyperextension

Extreme or overextension of limb or body part beyond its normal limit

Elevation

Act of raising of lifting a body part

Depression

Act of lowering a body part

Rotation

Circular movement around an axis such as the shoulder joint

Circumduction

Circular movement at the far end of a limb

Rotator Muscle

Turns a body part on its axis

Rotator Muscle

Group of muscles and their tendons that hold the head of the humerus securely in place

Supination

Act of rotating the arm or the leg so the palm of the hand or sole of the foor is turned forward or upward

Pronation

Act of rotating the arm or leg so the palm of the hand or sole of the foot is turned downward or backward

Dosrsiflexion

Movement that bends the foot upward at the ankle

Plantar Flexion

Movement that bends the foot downward at the ankle

Origin

The more stable of the two ends of a muscle attachment to bone

Located nearest the midline of the body or one a less movable part of the skeleton

Insertion

The more movable of the two ends of a muscle attachment to bone

In contrast to origin; more movable attachment that is farthest point from midline of the body

Sternocleidomastoid Muscle

Muscle Attachment to the sternum, clavicle, temporal bone

Flexor Capri

The muscles in the arm, Wrist and finger flexors on anterior aspect of the forearm

Capri: Wrist

Extension Capri(wrist)

Wrist and fingers extensors on the posterior aspect of the forearm

Pectoralis Major

Pectoral(chest) muscle of the anterior wall

Female: lies under the breast

Vastus Lateralis

Vastus(huge) muscle of the lateral side of the quadricep muscle in the anterior thigh

Vastus Medialis

Vastus(huge) muscle of the medial side of the quadricep muscle of the anterior thigh

Oblique

Slanted or at an angle

Rectus

Straight alignment with vertical axis of the body

Sphincter

Ring-like muscle; constricts opening

Transverse

Crosswire direction

Biceps Brachii

Also known as the biceps in the brachii(arm), located in the anterior upper arm

• Flexes the elbow

Formed from two divisions

Triceps Brachii

Also known as the triceps of the brachii(arm) and is located in the posterior upper arm

• Extends the elbow

Formed from three divisions

Biceps Femoris

Biceps in the thigh

Triceps Surae

Tricep in the calf muscle

Gluteus Maximus

largest muscle of the buttock

Deltoid Muscle

Shaped like an inverted triangle and forms the muscular cap of the shoulder

Hamstrings

Composed of three muscles of the posterior aspect of the thigh that are involved in knee flexion and hip extension

Frontalis (occipitofrontalis)

Muscle in the forehead, anterior to the frontal bone on the skull and what wrinkles the forehead

Temporalis Muscle

Covers the temporal bone and moves the lower jaw up and back to close the mouth

Masseter Muscle

In the cheek, one of the strongest in the body and moves the lower jaw up to close the mouth when chewing

External Oblique

Found on the lateral side of the abdomen, runs at an angle (\)

Internal Oblique

Found in the abdomen, runs at a different angle (/)

Rectus Abdominis

Helps flex the trunk in the middle abdomen straight down, and assists in breathing while also supporting the spine

Transverse Adominis

Across the abdomen on the side and is the deepest of the abdominis muscle

Deltoid

Forms the muscular cap of the shoulder

Trapezius Muscle

Moves the head and shoulder blade

Rectus Femoris

Straight muscle in the quadricep muscle group on the anterior thigh that extends the leg at the knee and flexes the thigh at the hip point

Quadriceps Femoris

Made up of four muscles on the anterior thigh that extends the knee

Gastrocnemius

Superficial muscle in the calf muscle that flexes the knee and bends the foot downward

Fascilitis

Inflammation of fascia

Fibromyalgia

Pain in the muscle fibers, an debilitating chronic condition

Tenosynovitis

Inflammation of the sheath surrounding a tendon

Tendinitis

Acute inflammation or irritation of tendons caused by excessive or unusual use of the joint

Adhesion

Band of fibrous tissues that holds structures together abnormally that are not usually connected

Atrophy

Weakness of wearing away of body tissues and structures caused by pathology or by disuse of the muscle over a long period of time

Cachexia

Physically wasting away due to loss of weight and muscle mass, occurs in pts with diseases such as advanced cancer or AIDS

Hernia

Tissue protruding through a weak area in the muscle normally containing it

Myalgia

Tenderness or pain in the muscles

Rhabdomyolysis

Death of muscle fibers releases contents into bloodstream; can lead to complications such as renal failure

Sarcopenia

Age related loss of muscle mass, strength, and function

Atonic

lacking normal muscle tone or strength

Hypotonia

Diminished tone of the skeletal muscles

Contracture

Permanent or longer term muscle contraction

Intermittent claudication (IC)

Vascular disease that involves pain in the leg muscles during exercise due to poor circulation causing pain, relieved by rest

Spasm

Sudden involuntary muscle contraction

Singultus (hiccups)

Myoclonus of the diaphragm

Cramp

Painful localized muscle spasm often named for its cause

Torticollis (wryneck)

Stiff neck; spasmodic contraction of neck muscles pulling head toward the affected side

Bradykinesia

Extreme slowness in movement

Myasthenia Gravis

Chronic autoimmune disease that affects the neuromuscular junction

Muscular Dystrophy (MD)

Progressive weakness and degeneration of skeletal muscles; general term for a group of more than 30 diseases

Compartment Syndrome

Compression of nerves and blood vessels in an compartment that separates groups of muscles in the arm or leg

Rotator cuff injuries

Tedinopathy: Irritation or degeneration of a tendon in any joint

Impingement syndrome

Rotator cuff tendinitis; tennis shoulder or swimmer’s shoulder

Carpal Tunnel Syndrome

Tendons that pass through the carpal tunnel are chronically overused, become inflammed and swollen and creates pressure on the median nerve

Epicondylitis

Inflammation of the tissue surrounding the elbow

Lateral: tennis elbow

Medial: Golfer’s elbow

Plantar Fasciitis

Inflammation of the plantar fascia on the sole of the foot

Sprain

Overstretched or torn ligament

Strain

Overstretched or torn muscle or tendon

Shin Injury

Tibialis anterior muscle tearing away from the shin bone

Iliotibial band syndrome (ITBS)

Caused by iliotibial band rubbing against bone, often in the area of the knee

• Runs from the lateral aspect of the thigh to the tibia, below the patella

Myoparesis

Weakness or slight muscular paralysis

Hemiparesis

Weakness or slight paralysis affecting one side of the body; common effect of a stroke

Hemiplegia

Total paralysis of half the body

Paraplegia

Paralysis of both legs and the lower part of the body

Quadriplegia

Paralysis of all four extremities

Deep tendon reflexes (DTRs)

Involuntary response to a stimulus

Electromyography

Diagnostic test that measures the electrical activity within muscle fibers

Muscle Biopsy

Removal of a plug of tissue for examination