The Muscular SystemThe Muscular System

Support SystemsSupport Systems

Unit 2Unit 2

Vocabulary- word partsVocabulary- word parts• My/o- muscle (myofibril is a muscle fiber)

• Ab- prefix, away (abduction)• Ad- prefix, towards (adduction)• Bi- prefix, two (biceps)• Tri- prefix, three (triceps)• Quad- prefix, four (quadriceps)• Contra- prefix, opposite or against

(contralateral- pertaining to the other side)• Dys- prefix, bad, difficult, or painful (dysphagia-

difficulty swallowing)

• -algia- suffix, pain (myalgia- muscle pain)

VocabularyVocabulary• Ligament- connective tissue that holds bone to

bone• Tendon- connective tissue that hold muscle to

bone• Tendonitis- inflammation of a tendon• Sprain- stretch or tear of a ligament• Strain- stretch or tear of a muscle or tendon• Myocardium- heart muscle• Thermogenesis- heat production• Striations- stripes

• MRI- Magnetic Resonance imaging

Functions of the Muscular SystemFunctions of the Muscular System

• Heat Production (thermogenesis)– Heat is a byproduct of muscle

contraction

• Movement Facilitation– Muscles shorten and pull on bones

which produces movement

• Structure (postural support)– Contraction of muscles keeps us

upright and maintains posture

Functions cont.Functions cont.

• Protection of Internal Organs – Contraction of abdominal muscles causes them to

become hard and offers protection to the underlying organs

– Other muscles con contract prior to receiving a blow thus protection bones and soft tissue.

• Controls the volume of hollow organs– Smooth muscle surrounds our hollow organs and

contractions propel the substances through them, aid in their emptying, or helps control their volume

• Stomach and small intestines• The bladder• Blood vessels

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Types of ContractibilityTypes of Contractibility

• Voluntary- contractions controlled by conscious thought or will

• Involuntary- contract due to unconscious impulses sent by the autonomic nervous system or certain specialized cells or hormones

Types of Muscles

Muscle AppearanceMuscle Appearance

• Striated- stripes, muscles that on a microscopic level have cross fiber stripes

• Non-striated- Not having stripes, muscles cells that microscopically have a smooth appearance

Cardiac MuscleCardiac Muscle

• Forms the bulk of heart wall (Myocardium)

• Striated• Involuntary • Cardiac fibers typically have a

centrally located nucleus• Intercalated discs

– Strengthens cardiac muscle tissue– Allows for special wringing muscle

contraction

Cardiac Muscle TissueCardiac Muscle Tissue

Smooth MuscleSmooth Muscle• Located in walls of hollow internal

surfaces such as:– blood vessels - stomach– urinary bladder - intestines

• Non-striated in appearance• Involuntary (typically)• Contractions usually move things

along, from point A to point B (peristalsis)

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Skeletal MuscleSkeletal Muscle

• Attached to bones

• Striated appearance under a microscope

• Voluntary control (conscious control)

• Allow for postural support and movement of body parts, both axial and appendicular

Skeletal Muscle TissueSkeletal Muscle Tissue

Connecting Tissues

Tendon – muscle to bone Ligament- bone to bone

MotionsMotions

• Peristalsis- a wave like motion by smooth muscle to advance substances

• Abduction- movement away from midline

• Adduction- movement towards midline

• Flexion- decreasing a joint angle

• Extension- increasing a joint angle

• Hyperextension- extension past normal extension, or past anatomical position

MotionsMotions

• Plantarflexion- specific to ankle motion, pointing the toes

• Dorsiflexion- specific to ankle motion, pulling the toes towards the shin

• Supination- turning palm up

• Pronation- turning palm down

• Rotation- movement around an axis

Location and Function of Skeletal MusclesLocation and Function of Skeletal Muscles

• Biceps brachii- anterior surface of arm between the shoulder and elbow, flexes the elbow

• Triceps brachii- posterior aspect of arm between the shoulder and elbow, extends the elbow

• Sternocleidomastoid – rotates head right and left• Trapezius- attaches to the spine from the occiput

through the thoracic region and to the spine of the scapula, extends or hyperextends the head and neck, (also helps with shoulder retraction and elevation and depression)

• Deltoid- covers the cap of the shoulder, abducts the arm

• Diaphragm- connects to the lower ribs and runs through the entire body, deflects the diaphragm inferiorly increasing volume of the thoracic cavity

Location and Function of Skeletal Location and Function of Skeletal MusclesMuscles

• Pectoralis major- attaches to the upper ribs along the sternum and to the humerus, adducts the arm

• Latissimus dorsi- attaches along mid to lower spine and pelvic and to the humerus, extends a flexed arm or hyperextends the arm from the anatomical position

• Rectus abdominus- attaches to the lower ribs and to the pelvic anteriorly, flexes the lumbar spine

• Gastrocnemius-attaches to the tibia and lower femur and uses the achilles tendon to attach to the calcaneous (heel bone), plantar flexes the ankle when the knee is in extension

Location and Function of Skeletal Location and Function of Skeletal MusclesMuscles

• Soleus- attached deep to the gastrocnemius on the tibia and uses the achilles tendon to attach to the calcaneous, plantarflexes the ankle when the knee is bent

• Hamstrings- posterior thigh between the hip and knee, flexes the knee – three muscles (Semimembranosus, Semitendenosus, Bicep Femoris)

• Quadriceps- anterior thigh between the hip and knee, extends the knee - four muscles (Vastas Lateralis, Vastus Intermedius, Vastus Medialis, Rectus Femoris)

• Sartorius – longest muscle in the body – attach at the illiac crest and inserts below the medical knee. Externally rotates hip and flexes the knee (figure 4 pos)

• Gluteus maximus- posterior pelvis, extends a flexed thigh or hyperextends the thigh from the anatomical position

Diseases and Diseases and Disorders of the Disorders of the

Muscular SystemMuscular System

TendonitisTendonitis

• Tendonitis is characterized by Inflammation of the tendons due to overuse or age-related changes of the tendon.

• It is common in individuals who begin a new exercise or increase their level of exercise.

• Age-related tendonitis is due to the loss of elasticity and the ability of the tendon to glide smoothly.

• Treatment includes: rest, ice, compression, and elevation (RICE).

Muscle SpasmMuscle Spasm

• An involuntary muscle contraction

• Also called a “Charlie Horse” or “muscle cramp”

• Main causes are electrolyte imbalances, dehydration and fatigue

Muscle Spasm cont.Muscle Spasm cont.

• Initial treatment is to put the muscle that has the spasm on stretch– If spasm persists ice or heat can be

used

• Prevention incudes maintaining a proper diet, drinking plenty of water and proper conditioning– Sports drinks may be beneficial

during exercise to help replace lost sodium due to sweating

StrainsStrains

• A tearing of a muscle or its attaching tendon

• Occurs when a muscle receives a stress that overcomes its strength– Sudden, quick heavy

lifting– During sports– While performing work

tasks

Strains cont.Strains cont.• 3 types of strains3 types of strains

• 11stst degree occurs when the muscle is stretched degree occurs when the muscle is stretched causing micro-tears in the muscle fiberscausing micro-tears in the muscle fibers

• 22ndnd degree sprain occurs when the muscle or degree sprain occurs when the muscle or tendon is partially torntendon is partially torn

• 33rdrd degree sprain occurs when the muscle is degree sprain occurs when the muscle is completely rupturedcompletely ruptured

• Signs & symptoms include:Signs & symptoms include:• Pain, especially when the muscle is Pain, especially when the muscle is

contractiong which limits functioncontractiong which limits function• SwellingSwelling• BruisingBruising

• Treatment includes Rest, Ice, Compression, Treatment includes Rest, Ice, Compression, ElevationElevation

Muscular DystrophyMuscular Dystrophy

• An inherited disorder in which the muscles are missing a certain protein causing degeneration of muscle tissue

• Causes progressive weakness and loss of function of the affected muscles

• There is no cure but physical therapy can lessen the severity of the disorder.

CareersCareers• Orthopedic SurgeonOrthopedic Surgeon

• Certified Athletic TrainerCertified Athletic Trainer

• Medical IllustratorMedical Illustrator

• Massage TherapistMassage Therapist

Orthopedic SurgeonOrthopedic Surgeon• Medical Doctor who specializes in

musculoskeletal ailments including acute, chronic, traumatic and overuse injuries

• Performs surgeries on musculoskeletal disorders such as ACL tears, Knee replacements, Scoliosis surgery

• Attends 4 year undergrad + 4 year medical school + 5 year orthopedic residency program + 1 year fellowship

• Salary- $300,000++• Arthroscopic surgery• http://www.youtube.com/watch?v=0e05b0GXc1E&safety_mode=true&persist_safety_mode=1&safe=ac

tive

Certified Athletic TrainerCertified Athletic Trainer

• Responsible for prevention, recognition, evaluation, immediate care and rehabilitation of injuries

• Work at high schools, universities, professional sports, gyms, industry, military, hospitals and clinics

• Bachelors Degree

• $35,000 +

• Athletic Training- Smooth Professional

• http://www.youtube.com/watch?v=qw3RHKTkBMk&safety_mode=true&persist_safety_mode=1&safe=active

Medical IllustratorMedical Illustrator• Artists who have detailed knowledge of the

human body• Create graphic representations of medical or

biological subjects for textbooks, pamphlets, exhibits, films, legal procedures, teaching models

• Pre-med/ Art Major• Masters of Medical Illustrating• Salary - $33,000-60,000• Job outlook is small and competitive, BUT

growing because of technology

Massage TherapistMassage Therapist• Manipulate patients body with pressure, tension or

vibration manually or with mechanical aids• Work in hospitals, nursing homes, sports and fitness

centers, spas, beauty salons, cruise ships, private offices

• Graduate from accredited Massage school (8 months to 12 months)and pass License exam

• Can specialize in pediatric massage, sports massage….• Salary varies

• Where do MT work and how much do they make

• http://www.youtube.com/watch?v=vSzVV9rPxXM&safety_mode=true&persist_safety_mode=1&safe=active

• Sports Massage• http://www.youtube.com/watch?v=Q9FDbYTx-

Xk&feature=BFa&list=SP15F63A96F48AB507&lf=list_related&safety_mode=true&persist_safety_mode=1&safe=active