Topographic Anatomy

• Superficial landmarks serve as guides to structures that lie beneath.

• Topographic anatomy applies to a body in the anatomic position.

  • The patient stands facing you, arms at the side, palms forward.

• Planes of the body: Imaginary straight lines that divide the body

  • Coronal plane: front/back

  • Transverse plane: top/bottom

  • Sagittal (lateral) plane: left/right

The Axial Skeleton

• The axial skeleton is the foundation to which the arms and legs are attached.

  • It includes:

    • Skull

    • Spinal column

    • Thorax

• Skull

  • Cranium: made up of 4 bones

  • Face: made up of 14 bones

• Spinal column

  • Composed of 33 bones (vertebrae)

  • Divided into 5 sections:

    • 7 Cervical

    • 12 Thoracic

    • 5 Lumbar

    • Sacrum

    • Coccyx

  • Thorax

    • Formed by 12 thoracic vertebrae and 12 pairs of ribs

    • The thoracic cavity contains:

      • Heart

      • Lungs

      • Esophagus

      • Great vessels

The Appendicular Skeleton

• Arms, legs, their connection points, and pelvis

• Occur wherever bones come in contact

• Hinge joint

  • Motion restricted to one plane

• Ball-and-socket joint

  • Allows rotation and bending

The Upper Extremities

• Composed of arms, forearms, hands, and fingers

  • Shoulder girdle

    • Clavicle

    • Scapula

    • Humerus

• Arm

  • Humerus is the supporting bone

  • Forearm

    • Radius on the lateral side

    • Ulna on the medial side

• Wrist and hand

  • Ball-and-socket joint

  • Principal bones:

    • Carpals

    • Metacarpals

    • Phalanges

The Pelvis

• Closed bony ring consisting of three bones

• Sacrum

• Two pelvic bones

  • Each pelvic bone is formed by the fusion of the ilium, ischium, and pubis.

• Posteriorly, the ilium, ischium, and pubis bones are joined by the sacrum.

• Anteriorly, the pubic symphysis is where the right and left pubis are joined.

The Lower Extremities

• Main components: thigh, leg, and foot

  • Femur (thighbone)

    • Femur connects to the pelvic girdle by a ball-and-socket joint

• The knee connects the upper leg to the lower leg

  • Kneecap (patella)

• Lower leg

  • Tibia (shinbone)

  • Fibula

• Ankle

  • A hinge joint

  • Allows flexion/extension of the foot

• Foot

  • 7 tarsal bones

  • 5 metatarsal bones

  • Toes are formed by phalanges

The Skeletal System: Physiology

• Functions of the skeletal system

  • Gives the body its shape

  • Protects fragile organs

  • Allows for movement

  • Stores calcium

  • Helps create blood cells

The Musculoskeletal System: Anatomy

• The musculoskeletal system provides:

  • Form

  • Upright posture

  • Movement

  • Protection for vital internal organs

• 3 types of muscle

  • Skeletal (voluntary) muscle - not striated

  • Smooth muscle - digestive system

  • Cardiac muscle - the heart

The Musculoskeletal System: Physiology

• Contraction and relaxation of this system make it possible to move and manipulate the environment.

• A by-product of this movement is heat.

• Another function of the muscles is to protect the structures under them.

The Respiratory System: Anatomy

• Structures of the body that contribute to respiration (the process of breathing)

Muscles of Breathing

• The diaphragm and intercostal muscles are the primary muscles of breathing.

• Other muscles involved in breathing:

  • Neck (cervical muscles)

  • Abdominal muscles

  • Pectoral muscles

The Respiratory System: Physiology

• Functions to provide the body with oxygen and eliminate carbon dioxide

• Ventilation and respiration are two separate, interdependent functions of the respiratory system.

• Respiration: the exchange of oxygen and carbon dioxide in alveoli and tissues

  • Provides oxygen to the cells and removes waste carbon dioxide

  • Diffusion: the passive process in which oxygen molecules move from an area with a higher concentration of molecules to an area of lower concentration.

  • The brainstem controls breathing.

• Ventilation: simple air movement into and out of the lungs

  • Tidal volume

  • Residual volume

  • Dead space

  • Minute volume

Characteristics of Normal Breathing

• Normal rate and depth (tidal volume)

• Regular rhythm or pattern of inhalation and exhalation

• Clear, audible breath sounds on both sides of the chest

• Regular rise and fall movement on both sides of the chest

• Movement of the abdomen

• Inadequate breathing patterns in adults:

  • Labored breathing

  • Muscle retractions

  • Pale, cyanotic, cool, damp skin

  • Tripod position

  • Agonal gasps (gasping breaths)

The Circulatory System: Anatomy

• A complex arrangement of connected tubes

  • Arteries, arterioles, capillaries, venules, veins

• Two circuits

  • Systemic circulation (body)

  • Pulmonary circulation (lungs)

The Heart

• Made of specialized cardiac muscle

• Works as two paired pumps

  • The septum divides the right and left sides

  • Each side is divided into:

    • Atrium (upper chamber)

    • Ventricle (lower chamber)

• Circulation

  • The heart receives its blood from the aorta.

  • The right side receives deoxygenated blood from the veins.

  • The left side receives oxygenated blood from the lungs.

• Normal adult resting heart rate (HR): 60–100 beats/min

• Stroke volume (SV)

  • Amount of blood moved by one beat

• Cardiac output (CO)

  • Amount of blood moved in 1 minute

  • HR × SV = CO

• Electrical conduction system

  • Causes smooth, coordinated contractions

  • Contractions produce the pumping action

Arteries

• Arteries carry blood from the heart to all body tissues.

• Pulmonary artery

  • Carries oxygen-poor blood to the lungs

• Arteries branch into smaller arteries and then into arterioles.

  • Arterioles branch into smaller vessels until they connect to the capillaries.

• Pulse

  • Created by the forceful pumping of blood out of the left ventricle and into major arteries

  • Palpated most easily at the neck, wrist, or groin

Capillaries & Veins

• Capillaries connect arterioles to venules

• Capillaries allow contact between blood and cells

• Veins return oxygen-depleted blood to the heart

  • The superior vena cava carries blood returning from the head, neck, shoulders, and upper extremities

  • The inferior vena cava carries blood from the abdomen, pelvis, and lower extremities

Spleen

• A solid organ located under the rib cage

• Filters blood

• Particularly susceptible to injury from blunt trauma

  • This can lead to severe internal bleeding

• Solids do not rupture, but hollow organs can

• Solid organs → internal bleeding, infection, sepsis, death

• Hollow organs → rupture of the organ, internal bleeding, sepsis

The Blood

• Blood composition

  • Plasma (liquid)

  • Red blood cells (erythrocytes)

  • White blood cells (leukocytes)

  • Platelets

• Blood pressure: the pressure blood exerts against the walls of the arteries

  • Systole occurs when the left ventricle contracts

  • Diastole occurs when the left ventricle relaxes

• Blood pressure readings

  • Systolic blood pressure: high point of wave

  • Diastolic blood pressure: low point of wave

• Normal circulation in adults

  • Automatically adjusted and controlled

  • Perfusion: circulation of blood in an organ or tissue in adequate amounts to meet the needs of its cells

  • Blood enters organs and tissues through arteries.

  • Blood leaves organs and tissues through veins.

• Inadequate Circulation in Adults

  • The system can adjust to small blood loss.

  • With a large loss, adjustment fails, and the patient goes into shock.

• Functions of blood

  • Perfusion

  • Transporting oxygen

  • Transporting carbon dioxide

  • Transporting wastes and nutrients

  • Clotting (coagulation)

The Nervous System

• The nervous system is perhaps the most complex organ in the body

• Divided into two main portions:

  • Central nervous system (CNS)

  • Peripheral nervous system

• Brain

• Controlling organs of the body

• Subdivisions

  • Cerebrum

  • Cerebellum

  • Brain stem

• Spinal cord

  • Continuation of the brain

  • Transmits messages between brain and body

Peripheral Nervous System

• Somatic nervous system

  • Transmits signals from the brain to voluntary muscles

• Autonomic nervous system

  • Involuntary actions

  • Split into two areas

    • Sympathetic nervous system (fight-or-flight)

    • Parasympathetic nervous system (slows body)

The Integumentary System: Physiology

• Two layers

  • Epidermis (superficial)

  • Dermis (deeper)

• Below the skin lies subcutaneous tissue.

  • Fat that insulates and serves as an energy reservoir

• The skin is the largest single organ in the body.

• Three major functions

  • Protect the body in the environment

  • Regulate body temperature

  • Transmit the information from the environment to the brain

The Digestive System: Anatomy

• Digestion: processing of food that nourishes the cells

• Abdomen: the second major body cavity

  • Contains major organs of digestion and excretion

  • Quadrants are the easiest way to identify areas:

    • Right upper

    • Lower upper

    • Right lower

    • Left lower

• Mouth

  • Lips, cheeks, gums, teeth, tongue

  • Salivary glands

• Oropharynx

• Esophagus

• Stomach

• Pancreas

• Liver

  • Bile ducts

• Small intestine

• Large intestine

• Appendix

• Rectum

The Digestive System: Physiology

• Enzymes are added to food.

  • By salivary glands, stomach, liver, pancreas, and small intestine

• Enzymes convert food into basic sugars, fatty acids, and amino acids.

  • Further processed by the liver

  • Circulated via blood throughout the body