Beverley Henderson

Article / Updated 08-11-2021

What makes up the inside of your body, from cells to organs and everything in between, lends itself to an abundance of body part-related medical terms. All the root words and combining forms can morph into all kinds of different words that explain everything from everyday common conditions and procedures to pathology and pharmacology. Remember that you can take any root word or combining form and create several different medical terms. Root Word What It Means Example(s) Abdomin/o Abdomen Abdominoplasty: Surgical repair or reconstruction of the abdomen Angi/o Vessel Angioplasty: Surgical repair or reconstruction of a vessel Arteri/o Artery Arterioplasty: Surgical repair or reconstruction of an artery Arthr/o Joint Arthritis: Inflammation of a joint Arthroplasty: Surgical repair or reconstruction of a joint Audi/o Hearing Audiometry: Measurement of hearing using an audiometer Bio Life Biology: The study of life and living organisms Bronch/i, bronch/o Bronchus/lung Bronchitis: Inflammation of the bronchi Bronchoscopy: Visual examination of the bronchi Cardi/o Heart Cardiomegaly: Enlargement of the heart Cardiac: Pertaining to the heart Carditis: Inflammation of the heart Cholecyst/o Gallbladder Cholecystectomy: Removal of the gallbladder Cholecystitis: Inflammation of the gallbladder Chondr/i, chondr/o Cartilage Chondromalacia: Softening of cartilage Col/o Colon Colonoscopy: Visual examination of the colon Colonoscope: Instrument used in colonoscopy Cry/o Cold Cryobiology: Branch of biology dealing with effects of low temperatures Cysti, cyst/o Bladder, or cyst Cystectomy: Surgical removal of a simple cyst or of the urinary bladder Cystitis: Inflammation of the bladder Cystogram: Radiograph of the bladder Cystopexy: Surgical fixation of the bladder to abdominal wall Cyt/o Cell Cytology: Study of cells Duoden/o Duodenum Duodenotomy: Surgical cutting into the duodenum Duodenectomy: Surgical removal of the duodenum Duodenitis: Inflammation of the duodenum Encephal/o Brain Encephalitis: Inflammation of the brain Episi/o Vulva Episiotomy: Surgical cutting of the vulva Erythr/o Red Erythrocytes: Red blood cells Erythema: Reddening of the skin Esophag/o Esophagus Esophagitis: Inflammation of the esophagus Esophagogastroduodenoscopy (EGD): Visual examination of the esophagus, stomach, and duodenum by scope Galact/o Milk Galactorrhea: Spontaneous flow of milk when nursing Gastr/o Stomach Gastritis: Inflammation of the stomach Gastrectomy: Surgical removal of the stomach Gastrodynia: Stomach ache Glyc/o Sugar Glycosuria: Sugar in the urine Gynec/o Female Gynecologist: Physician who studies and treats diseases of female reproductive organs Hemat/o, hem/o Blood Hematocyte: Blood cell Hepat/o, hepatic/o Liver Hepatitis: Inflammation of the liver Heter/o Other, different Heterosexual: Sexually attracted to the opposite sex Hist/o, histi/o Tissue Histology: Study and function of tissue Hom/o, home/o Same, alike Homosexual: Sexually attracted to the same sex Hydr/o Water, wet Hydromassage: Massage by means of moving water Hyster/o Uterus Hysterectomy: Surgical removal of the uterus Ile/o Ileum (intestine) Ileostomy: Artificial opening into the ileum Ileitis: Inflammation of the ileum Ili/o Ilium (pelvic bone) Ilioinguinal: Pertaining to the ilium and inguinal regions Jejun/o Jejunum Jejunitis: Inflammation of the jejunum Jejunostomy: Artificial opening into the jejunum Lacrima Tears Lacrimatory: Causing a flow of tears Laryng/o Larynx Laryngitis: Inflammation of the larynx Laryngectomy: Surgical removal of the larynx Leuk/o White Leukocyte: White blood cell Lith/o Stone or calculus Lithotripsy: Crushing of a stone or calculus Men/o Menstruation Menorrhea: Menstrual flow Menorrhagia: Excessive or heavy menstrual flow Myel/o Bone marrow/spinal cord Myelogram: Recording of the spinal cord My/o Muscle Myositis: Inflammation of a muscle Myalgia: Pain in a muscle or painful muscle Nat/o Birth Prenatal: Before birth Postnatal: After birth Necr/o Death Necrosis: Death of a cell Necrophobia: Morbid fear of death or dead bodies Nephr/o Kidney Nephrectomy: Surgical removal of a kidney Neur/o, neur/i Nerve Neurologist: Physician who studies and treats conditions of the nervous system Oophor/o Ovary Oophorectomy: Surgical removal of an ovary Oophoritis: Inflammation of an ovary Orchid/o, orchi/o Testis Orchialgia: A pain in the testicle Orchiectomy: Surgical removal of a testicle Peritone/o Peritoneum Peritoneal: Pertaining to the peritoneum Peritonitis: Inflammation of the peritoneum Pharyng/o Pharynx Pharyngitis: Inflammation of the pharynx (sore throat) Pleur/o, pleur/a Pleura, rib (side) Pleurisy: Inflammation of the lining of the chest cavity Pleurolysis: Surgical separation of pleural adhesions Pneum/a/o/ato/ono Lungs Pneumonitis: Inflammation of the lung Proct/o Rectum, anus Proctologist: Physician who studies and treats diseases of rectum and anus Pulmon/o Lungs Pulmonary: Pertaining to the lungs Pyel/o Renal pelvis Pyelography: Radiograph (x-ray) of the pelvis of the kidneyPyelolithotomy: Removal of a stone from the kidney pelvis Rect/o Rectum Rectosigmoid: Pertaining to the rectum and sigmoid Salping/o Fallopian tube Salpingectomy: Surgical removal of a fallopian tube Sarc/o Flesh Sarcoid: Resembling flesh Splen/o Spleen Splenomegaly: Enlargement of the spleen Splenectomy: Surgical removal of the spleen Tend/o, ten/o, tendin/o Tendon Tendinitis (or tendonitis): Inflammation of a tendon Testicul/o Testis Testicular: Pertaining to a testis or testicle Testitis: Inflammation of a testis Thorac/o Chest Thoracotomy: Incision into the chest cavity Thoracentesis: Surgical puncture into chest cavity Tonsill/o Tonsils Tonsillectomy: Surgical removal of tonsils Tonsillitis: Inflammation of the tonsils Ureter/o Ureter Ureterolithotomy: Removal of a calculus (stone) from a ureter by means of incision Ureteropelvic: Pertaining to the ureter and pelvis of the kidney Urethr/o Urethra Urethritis: Inflammation of the urethra Urethropexy: Surgical fixation of the urethra Vas/o Vas deferens Vasectomy: Surgical removal of portion of vas deferens for male sterilization Viscer/o Viscera (organs) Viscerography: Radiography of the viscera

Cheat Sheet / Updated 03-14-2021

Grasping medical terminology starts with knowing the body’s systems, recognizing medical root words commonly used, understanding the Greek influence in medical terminology, and learning those pesky hard-to-spell medical words.

Article / Updated 01-15-2020

The urinary system is made up of the kidneys (you have two), ureters (also two), bladder, and urethra (one). This system’s main function is to remove urea, the waste product of metabolism, from the bloodstream and excrete the urea (in the urine) from the body. So, how does that big steak dinner you ate last night turn into the next morning’s output in the form of urine? Well, food and oxygen combine in cells to produce energy, a process called catabolism. In the process, food and oxygen are not destroyed, but small particles making up the food and oxygen are rearranged in new combinations, and part of the result is waste products. Waste products in the form of gases (carbon dioxide) are removed from the body by exhaling through the lungs. Nitrogenous waste (the by-product of protein food) is more difficult to excrete from the body than gases. This kind of waste is secreted as a soluble dissolved in water, a waste substance called urine. The main function of the urinary system is to remove urea from the bloodstream. Urea is formed in the liver from ammonia (which is, believe it or not, basically the same stuff you use to clean the kitchen). The bloodstream carries it (in the same manner as hormones and lymph) to the kidneys, where it passes with water, salts, and acids out of the bloodstream into the kidneys. The kidneys remove waste products, producing urine that travels through each ureter into the bladder. Urine is then excreted from the bladder via the urethra. Magically (or so it might seem), your steak dinner has turned into pee! Kidneys You have two kidneys, unless you’ve had one removed. Kidneys are dark reddish brown, bean-shaped organs that are located behind the abdominal cavity on each side of the spine in the lumbar region. They are embedded in a cushion of adipose (fat) tissue and surrounded by connective tissue for support. Each kidney is about the size of a fist and weighs approximately 8 ounces. The left kidney is a little larger and sits a little higher than the right one. Each kidney consists of an outer cortex and an inner medulla region. The cortex contains millions of nephrons, and the medulla contains the collecting tubules (small tubes). A segment on the medial border of each kidney, called the hilum, allows the blood vessels, nerves, and ureter to pass through. The nephron is the kidney’s functional and structural unit, or the “brains” of the kidney. Each is a urine-producing microscopic structure, consisting of a renal corpuscle and renal tubule. Hilum’s Latin meaning is “a small thing or a trifle.” This is a term for a depression or pit in an organ where vessels and nerves enter. Glomeruli (singular glomerulus) are clusters of capillaries (small vessels) at the entrance of each nephron. They help filter the blood, beginning the process of urine production. In the blood-filtering process, water and solutes from the blood in the glomeruli pass through the capillaries and the walls that make up the glomeruli into the tubules. Tubules have the ability to remove substances your body needs and return them to the blood. The Greek word pyelos means “tub-shaped vessel,” which describes the shape of each kidney. Ureters You have two ureters (right and left). They are muscular tubes about 15–18 inches long, lined with mucous membrane, extending from the renal pelvis down to the bladder. The left ureter is longer because the left kidney sits higher in position. The urine enters the bladder in spurts via each ureter every 10–30 seconds. At the bladder entrance is a ureteral orifice (opening) that opens to allow urine into the bladder from each ureter. The orifice works in sequence with the peristaltic (wavelike) action that propels the urine through the ureter. This action prevents urine from flowing back into the ureter when the bladder contracts. Urinary bladder The urinary bladder is a hollow, very elastic muscular sac in the pelvic cavity. It acts as a temporary reservoir or “holding tank” for urine. It has two openings to receive the urine coming from each ureter. Another opening, the urethra, provides an exit route for the urine out of the body. The trigone is a triangular space at the base of the bladder where the ureters enter the bladder. An average bladder holds more than 250 ml of urine before producing the desire to urinate. Contraction of the bladder and internal sphincter is an involuntary action, whereas the action of the external sphincter is controlled by you. The act of preventing or concluding voiding (urination) is learned and voluntary in a healthy body. Urethra The urethra is a membranous tube that carries urine from the bladder to the exterior of the body. The process of expelling or voiding urine is technically called micturition. The external opening of the urethra is the urethral meatus or urinary meatus. The female urethra is about 11/2 inches long, and its only function is urination. In the male, it is approximately 8 inches long. It extends from the bladder neck through the prostate and through the penis. The male urethra carries both urine and reproductive organ secretions. Thanks to Mother Nature, the urethra can’t mix sperm and urine, so it’s difficult to pee with an erection. That sure prevents unwanted embarrassment during those tender moments. Catheter comes from the Greek catheter, meaning “a thing let down.” A catheter lets down urine from the bladder. Micturate comes from the Latin mictus, which means “a making of water.” From the verb micturate comes the noun micturition. Be sure to note the spelling: Micturition (expelling urine) is often misspelled as micturation. The p is silent in pneumonia, just as pee is silent in a swimming pool. That’s why you probably should not frequent swim-up bars on vacation. You never know what is lurking in the water.

Article / Updated 01-03-2020

Your skin (the body’s largest organ), glands, nails, and hair — also known as the integumentary system — serve as the “public face” of your body. Consider it your marketing team, letting the world know by their condition how healthy the rest of your body is. Healthy skin, along with accessory organs glands, hair, and nails, are the hallmarks of healthy insides, so care for them accordingly. Sebaceous and sudoriferous glands The skin has two types of glands that, as accessory organs, produce important secretions. These glands under the skin’s surface are called the sebaceous (oil) glands and the sudoriferous (sweat) glands. The sebaceous glands produce an oily secretion called sebum, whereas the sudoriferous glands produce a watery secretion called sweat. Sebum and sweat are carried to the outer edges of the skin by ducts and excreted through openings in the skin called pores. Sebum helps lubricate the skin. Sebaceous glands are closely associated with hair follicles, and their ducts open into the hair follicle through which the sebum is released. Sebaceous glands are influenced by sex hormones. This causes them to be overactive at puberty and underactive in old age. This explains the excess oil production of the skin at puberty and gradual drying of the skin as we age. Sudoriferous (sweat) glands are tiny coiled glands found on almost all body surfaces. You have about 2 million of them in your body. There are many more in the palms of the hands, and you’d find approximately 3,000 glands per square inch on the sole of your foot. The tiny openings on the surface are called pores. Sweat helps cool the body as it evaporates from the skin surface. Nerve fibers under the skin detect pain, temperature, pressure, and touch. The adjustment of the body to its environment depends on the sensory messages relayed to the brain and spinal cord by the sensitive nerve endings in the skin. Diaphoresis comes from the Greek dia, meaning “through,” and phoreo, meaning “I carry.” Translated, it means “the carrying through of perspiration.” The following figure illustrates the layers of the skin and some of its structures. Stinking it up: Your sweat glands Sweat gets a bad rap for being smelly when, in fact, it’s not your fault. Your body’s smell is caused by bacteria. Sweat or perspiration is almost pure water, with dissolved materials such as salt making up less than 1 percent of its total composition. Sweat is actually colorless and odorless. The odor produced when sweat accumulates is due to the action of bacteria on it. Certain sweat glands, active only from puberty onward and larger than ordinary sweat glands, are concentrated near the reproductive organs and in the axillae (armpits). These glands secrete an odorless sweat that contains substances that are easily broken down by skin bacteria. The breakdown products are responsible for the characteristic “human body odor.” So the next time someone tells you your sweat stinks, you can say, “I beg to differ. My bacteria are the culprits.” The ceruminous glands are classified as modified sweat glands and are found in the ear canal. These glands produce a yellow waxy substance called cerumen (ear wax). Hair and Nails A hair fiber is composed of a network of horny cells (hold your giggles, please) filled with hard protein called keratin. Hair growth is similar to the growth of the epidermal layer of the skin. Deep-lying cells in hair roots move forward through the hair follicles, or shafts, that hold the hair fiber. Melanocytes located at the root of hair follicles supply the melanin pigment for the hair fiber. Hair color depends on the amount of melanin present, as it does with the color of the skin. Because hormone production decreases as we get older, the hair loses color and becomes transparent (which we see as gray). Nails are hard keratin plates that cover the dorsal (top) surface of the last bone of each toe and finger. Nails are composed of horny cells that are cemented together and can extend indefinitely until cut or broken. A nail grows in thickness and length by division of the cells of the nerve root, at the base of the nail plate. Nails grow approximately 1 millimeter a week, which means that fingernails may regrow completely in three to five months. Toenails grow more slowly than fingernails, but if you have lost a toenail due to a nasty stubbing incident, it will come back eventually.

Article / Updated 01-03-2020

The musculoskeletal system is made up of muscles and joints. The muscles — all 600 of them and more — are responsible for movement. The skeleton provides attachment points and support for muscles, but it’s the muscle tissue’s ability to extend and contract that makes movement happen. So, for every climb of the elliptical machine, you can thank muscular tissue for making it possible. Muscles make up the major part of fleshy portions of the body and account for one half of body weight. Muscles vary in proportion to body size, and the shape of the body is determined by muscles covering bones. Muscles account for 40 percent of our total body weight; the skeleton accounts for only about 18 percent. Muscular expanding and contracting doesn’t just happen in your biceps. It happens all over the body. Muscles support and maintain posture and produce body heat. They help form many internal organs and regulate the work those organs do behind the scenes (such as the heart, uterus, lungs, and intestines) even when the body is not moving. The muscles of arteries, intestines, heart, and stomach, for example, are always at work even when we aren’t thinking of them. However, the silent work muscles do inside your body is wholly different from more obvious muscular work done by your arms and legs, for example. Internal movement involves the contraction and relaxation of involuntary muscles, muscles that we cannot consciously control. For example, heartbeats are performed by cardiac muscles. Breathing and digestion are facilitated by muscles called visceral (involuntary) muscles, whereas external movement is accomplished by contraction and relaxation of muscles that are attached to bones. The muscles that provide this external movement are known as voluntary muscles, as they perform movements on command. All bodily movement, whether lifting of an arm, or the beating of the heart, involves the contraction and relaxation of voluntary or involuntary muscles. Classes of muscles The class system is alive and well, at least as far as your muscles are concerned. There are three classes of muscles: skeletal, visceral, and cardiac. Cardiac (involuntary striated) muscle has branching fibers and forms most of the wall of the heart. Its contraction produces the heartbeat. Skeletal (voluntary striated, meaning striped) muscles, are attached to the skeleton. They are called voluntary, of course, because they are controlled by your will. This type of muscle can be easily seen by flexing the forearm, which makes the biceps muscle become hard and thick. Visceral (involuntary smooth) muscle is found in the stomach, intestines, and blood vessels, and cannot be controlled at will. Unlike other muscle, cardiac (heart) muscle keeps beating even when removed from the body, as in a heart transplant. And even if it stops beating, it can be jump-started with an external electrical charge. Not so with the other muscles. Types of muscles Oh, if it were only that easy. But there are also types of muscles. At first glance, the types of muscles are the same as the classes of muscle. But pay close attention and you’ll see there are subtle differences. There are three types of muscles in the body. Striated muscle Striated muscles are also called skeletal or voluntary muscles. These are the muscles that move all the bones, as well as the face and the eyes. The body is able to consciously control the activity of a striated muscle. Smooth muscle The second type of muscle is smooth muscle, also known as visceral, involuntary or unstriated muscle. The body has no conscious control over smooth muscles, which move the internal organs such as the digestive tract. The smooth muscles are also found in blood vessels and secretory ducts leading from glands. Skeletal muscle fibers are arranged in bundles, but smooth muscles form sheets of fibers that wrap around tubes and vessels. Cardiac muscles The third type of muscle is cardiac muscle. It is striated in appearance but is like smooth muscle in its actions. Movement of cardiac muscle cannot be consciously controlled. Cardiac muscle has branching fibers forming most of the wall of the heart and controlling the contractions producing the heartbeat. Muscles and tendons Now that you know the classes and types of muscles, let’s take a more in-depth look at how they work. You already know that skeletal muscles, or striated muscles, are the muscles that move the bones of the body. Now get ready for the scoop on what makes it possible. When a muscle contracts, one of the attached bones remains stationary, as a result of other muscles holding it in place. The point of attachment of the muscle to the stationary bone is called the origin or beginning of that muscle. When the muscle contracts, another bone to which it is attached, does move. The junction of the muscle to the bone that moves is called the insertion of the muscle. Near the point of insertion, the muscle narrows and is connected to the bone by a tendon. One type of tendon that helps attach bone to muscles is called an aponeurosis. It takes 200 muscles working together to take a step. Roundup of the superficial muscles Sometimes, being superficial isn’t a bad thing. Take, for example, your superficial muscles, so named because these are the muscles you’re most likely to see with the naked eye. These workhorses of the muscular system help make you unique. Though they all have complicated-sounding names, they help your body perform everyday functions like picking up objects and smiling. The following figures illustrate four major muscle groups. Arm muscles consist of the upper arm muscles, biceps brachii and triceps brachii. In the forearm (lower arm) are the flexor and extensor muscles of the hands and fingers. Head and face muscles include the frontalis, temporalis, orbicularis oculi, orbicularis oris, occipitalis, mentalis, buccinator, zygomatic major and minor, and the masseter Shoulder and neck muscles include the sternocleidomastoid, pectoralis major, latissimus dorsi, and trapezius muscle, leading to the deltoid muscle of the shoulder. The major chest and abdominal muscles consist of the diaphragm, pectoralis major, the rectus abdominis, and the external oblique. Also associated with this region is the linea alba. The linea alba (meaning “white line”) is a vertical band of connective muscular tissue that begins at the xiphoid process (sternum) and ends at the symphysis pubis (where the iliac bones join at the front of the pelvis). The major muscles of the back include the seventh cervical vertebral muscle, infraspinatus, supraspinatus, latissimus dorsi, and the rhomboid major muscle. The seventh cervical vertebra muscle is a muscle, whereas the seventh vertebra is a bone. Many muscles, tendons, and ligaments have the same name but don’t have the same function. In this case, the seventh cervical muscle is a point of attachment aiding in support and movement of head and neck. The pelvis and anterior thigh muscles include the tensor fascia lata, the adductors of the thigh, the vastus lateralis and vastus medialis, the rectus femoris, and the The lower leg muscles from the knee to the ankle includes the gastrocnemius, which makes up a large portion of the calf muscles, the tibialis anterior, soleus, peroneus longus, and peroneus brevis. By the way, things aren’t always what they seem: The Achilles tendon is technically classified as a muscle. From the back, the buttocks are composed of the gluteus maximus and gluteus medius. In the thigh are the adductor magnus, vastus lateralis, and gracilis, whereas the biceps femoris, semitendinosus, and semimembranosus combined comprise the hamstrings. So, the moral of our muscle story is teamwork. Bones cannot move alone without being attached to muscle. Muscles cannot move alone, without being attached to stationary bones to allow support for that movement. Neither bones nor muscles could function without the attachments provided by the tendons and ligaments. Body movement then, is made possible by the bones and skeletal muscles working together in addition to the visceral and cardiac muscles that function to maintain the muscular rhythm of our vital organs. It’s all one big, happy family of muscles.

Article / Updated 01-03-2020

Although bones, muscles, joints, ligaments, and tendons all work together, they each have a special job. Bones provide the framework for your body but ligaments and tendons provide the attachments for muscles to contract and relax. Bones store mineral salts, and the inner core of a bone is composed of hematopoietic (blood cell–forming) red bone marrow. Other areas of the bone are used as storage areas for minerals necessary for growth, such as calcium and phosphorus. And you thought bones just gave your body its shape. In fact, they operate as your body’s Fort Knox of vital minerals. Talk about double duty! Red bone marrow is red because red blood cells form in it. In adults red marrow is eventually replaced by yellow marrow, which stores fat. Bones are complete organs, chiefly made up of connective tissue called osseous or bony tissue plus a rich supply of blood vessels and nerves. Colles’ fracture was first described by Dr. Andrew Colles, an Irish surgeon in 1814. It is a fracture of the distal end of the radius (distal meaning the portion of a body part farthest from the point of origin). But you don’t have to be Irish to sustain one. In this case, the point of origin is the shoulder, looking at the limb separately, and not the body as a whole. Bones and osteology Now it’s time to get down with osteology. No, it’s not a slick new dance move. Osteology is the study of bones. Notice the root word osteo? You might know it as part of the word osteoporosis — a common condition typical in women involving the loss of bone density (in fact, four out of five Americans with osteoporosis are women). So osteo is the focus in this chapter. The first step into the world of osteology is looking at the actual makeup of our bones. Bones of the hands and feet make up over half of our 206 total bones, while the skull is comprised of 22 bones. Bones are classified by their shape — long, short, flat, irregular, and sesamoid. Like this: Long bones, found in arms (the humerus is the upper arm) and legs (the femur is your thigh) are strong, broad at the ends where they join with other bones, and have large surface areas for muscle attachment. Short bones are found in the wrists and ankles and have small, irregular shapes. Flat bones are found covering soft body parts. The shoulder blades, ribs, and pelvic bones are examples of flat bones. Vertebrae are examples of irregular bones. Sesamoid bones are small, rounded bones found near joints. The kneecap is an example of a sesamoid bone. There’s more to bones than the hard, white substance you think of when you envision one. For starters, the shaft or middle region of a long bone is called the diaphysis. Each end of a long bone is called the epiphysis. Both are joined by the physis, also called the growth plate. The periosteum of the bone is a strong, fibrous membrane that covers the surface, except at the ends. Bones other than long bones are completely covered by the periosteum. Fractures are often classified by a system called the Salter-Harris system, which identifies whether a fracture involves only the physis, or could involve the epiphysis and/or the diaphysis as well. Basically, it’s a fancy way of saying what area of bone is affected by a break and classifying the level of seriousness of that break. Beneath the periosteum is a level of osteoblasts, which deposit calcium and phosphorus compounds in the bony tissue. Articular cartilage covers the ends of long bones. This cartilage layer cushions the bones where they meet with other bones, or at the joints. The compact bone is made of dense tissue lying under the periosteum in all bones. Within the compact bone is a system of small channels containing blood vessels that bring oxygen and nutrients to the bone and remove waste products such as carbon dioxide. Bones are 31-percent water, and pound-for-pound, they are four times stronger than concrete. The hardest of these is your jaw bone. Cancellous bone, sometimes called spongy bone, is more porous and less dense than compact bone. Spaces in cancellous bone contain red bone marrow, which is richly supplied with blood and consists of immature and mature blood cells in various stages of development. The ribs, the pelvic bones, the sternum or breastbone and vertebrae, as well as the epiphyses of long bones, contain red bone marrow within cancellous tissue. Figure 12-1 illustrates the skeleton. Axial skeleton Think of the word axis when you think about the axial skeleton. The bones that make up this particular part of the skeleton tend to encircle important organs or rotate in an axial motion. The axial skeleton includes the heavy hitters in this section. Cranium The bones of the cranium (skull) protect the brain. The bones of the skull include the frontal bone, which forms the forehead and bony sockets that contain the eyes. The parietal bone forms the roof and upper sides of the skull. Two temporal bones form the lower sides and base. The mastoid process is a small round part of the temporal bone behind the ear. The occipital bone forms the back and base of the skull and joins the parietal and temporal bones, forming a suture (a joining line) of cranial bones. The occipital bone has an opening called the foramen magnum through which the spinal cord passes. The sphenoid bone extends behind the eyes and forms part of the base of the skull. It joins the frontal, occipital, and ethmoid bones and serves as an anchor to hold these bones together. The ethmoid bone is a thin delicate bone, supporting the nasal cavity and forms part of the orbits of the eyes. Be careful when working with a newborn cranium, as the cranial bones of a newborn are not completely joined. There are gaps of unossified tissue (tissue that is still in the fibrous membrane stage) in the skull, called the soft spot or fontanelle. The lines where the bones of the skull join are called cranial sutures. The pulse of blood vessels can be felt under the skin in these areas. Facial bones All the facial bones except one are joined together. Only the mandible, or lower jaw bone, is capable of moving, which is necessary for chewing and speaking. Other facial bones include the nasal bones, and the maxillary bones. Two large bones compose the upper jaw. Both the mandible and maxilla contain sockets called alveoli, in which the teeth are embedded. The mandible joins the skull at the temporal bone, forming the lengthily named temporomandibular joint. The zygoma or zygomatic bones form the cheek. Together, these bones create a sort of mega-bone that makes up the upper portion of your face. Vertebral column The vertebral column, or spinal column, is composed of 26 bone segments called vertebrae (singular vertebra), which are arranged in five divisions: cervical, thoracic, lumbar, sacrum, and coccyx (tailbone). The first seven vertebrae are called the cervical vertebrae (C1-C7). These vertebrae do not join with the ribs. The first cervical vertebra, C1 (also known as the atlas), articulates with the occipital bone of the skull at the back of neck. It supports the head and allows it to move forward and back. The second cervical vertebra, C2 (the axis), acts as a pivot, about which the atlas rotates, allowing head to turn from side to side, extend, and flex. The second division consists of 12 thoracic vertebrae (T1-T12). These vertebrae join with the 12 pairs of ribs. The third division consists of five lumbar vertebrae (L1-L5). They are the strongest and largest of the back bones. The sacrum is a slightly curved triangular bone, composed of five separate segments, or sacral bones, that gradually become fused. The coccyx is the tailbone. It is also a fused bone, formed from four small coccygeal bones. The Greek diskos means “flat plate.” An example is the lumbar disk. And coccyx comes from the Greek word for cuckoo; it resembles a cuckoo’s beak. A vertebra is composed of a disk-shaped portion called the vertebral body, which is the solid anterior portion (closest to body front, farthest from the body back). A lamina is a part of the posterior (back) portion of a vertebra. Spinous processes, thoracic processes, and transverse processes are little wing-like projections that project or extend from each vertebra. The foramen is the opening in the middle of each vertebra that the spinal cord passes through. Between the body of one vertebra and the bodies of vertebrae lying beneath are vertebral disks, which help to provide flexibility and cushion shock to the vertebral column. Thorax The thorax (not to be confused with a character invented by Dr. Seuss) starts with the clavicle, or the collarbone, connecting the sternum (breastbone) to each shoulder. The scapula is the shoulder blade, consisting of two flat triangular bones, one on each back side of the thorax. The scapulae extend to join with the clavicle at the acromion. The shoulder blade connects to the body by 15 different muscles but not by a single bone connection. The sternum is the breastbone, the flat bone extending down the midline of the chest. The uppermost part of the sternum joins to the sides of the clavicle and ribs, whereas the other, narrowed portion is attached to the diaphragm. The lower portion of the sternum is the xiphoid process, the small, mobile bone tag on the very end of the sternum. This is the thing you would feel for when placing your hands on a chest to perform CPR. The 12 pairs of ribs are close neighbors with the sternum. The first seven pairs join the sternum anteriorly (at the chest) by attachments of costal cartilage. Ribs 1–7 are called true ribs. Ribs 8–12 are called false ribs. The false ribs join with the vertebral column in the back, but join the 7th rib anteriorly and do not attach to the sternum. Ribs 11 and 12 are called floating ribs because they are completely free at their anterior end. The ribs move five million times a year — every time you breathe. Pelvis The pelvic girdle or hip bone is a large bone that supports the trunk of the body and joins with the femur (thigh bone) and sacrum. The adult pelvic bone is composed of three pairs of fused bone: the ilium, the ischium, and the pubis. The ilium is the uppermost and largest portion. The connection between the iliac bones and the sacrum is so firm that they are often referred to as one bone, the sacroiliac. The iliac crests are found on both the anterior and posterior portions of the pelvis. They are filled with red bone marrow and serve as an attachment for abdominal wall muscles. The ischium is the posterior portion of the pelvis. The ischium and the muscles attached to it are what we sit on. The pubis is the anterior portion containing two parts that are joined by way of a disk. This area of fusion is called the pubic symphysis. The region within the bone formed by the pelvic girdle is called the pelvic cavity. The rectum, sigmoid colon, bladder, and female reproductive organs are contained in this cavity. Appendicular skeleton Think of the word appendage when your thoughts turn to the appendicular skeleton. Your reachers, grabbers, and hoofers are all covered in this section. Appendages fall into two major categories of bones. Upper extremities Arms and hands are part of this category. The bones of the arm and hand include the humerus, the upper arm bone. The large head of the humerus is round and joins the scapula and clavicle. The ulna and radius are the bones of the lower arm or forearm. The bony prominence of the ulna at the elbow is called the olecranon. Carpals are wrist bones. Finally, there are two rows of four bones. The metacarpals are five bones radiating to the fingers. Phalanges (the singular is phalanx) are the finger bones. Each finger has three phalanges: the proximal, middle, and distal. The proximal is the phalange closest to the point of origin, whereas the distal is farthest from the point of origin. So, the proximal would be the first after the knuckle, the middle would be in the middle, and the distal at the fingertip. The thumb has only two phalanges: medial and distal at tip of the thumb, which is why it is categorized differently than the rest of your fingers. Diaphysis comes from Greek diaphusis, meaning “state of growing between.” Diaphysis is the shaft of long bones that grows as children grow. Leg and foot The femur is the thigh bone. At the top end of it, a rounded head fits into a socket in the hip bone called the acetabulum. The patella, or kneecap, is a small flat bone that lies in front of the joint between the femur and one of the lower leg bones called the tibia. The tibia is the larger of the two lower bones of the leg, often referred to as the shin bone. The fibula is the smaller of the two bones. The tarsals, or ankle bones, are short bones that are much like the carpal bones of the wrist, but larger. The calcaneus, the largest of these bones, is also called the heel bone. Metatarsals compose the forefoot or bones leading to the phalanges in the toes. There are two phalanges in the big or great toe and three in each of the other four toes. Just like the fingers, all the bones in the toes are phalanges, from proximal to distal. In the big or great toe they are called the proximal and distal, differing slightly from the thumb. The femur is the longest bone in the body and accounts for one quarter of your total height. Joints Now think about the “glue” that holds all these bones together. Okay, joints aren’t really made of glue, but they sure do a good job of keeping everything connected. Let us articulate that concept a bit better: Joints, also called articulations, are the coming together of two or more bones. Some are not movable, such as the suture joints between the cranial bones. Some joints only partially move, such as joints between the vertebrae. Most joints do allow movement. These freely movable joints are called synovial joints. An example is the ball and socket type — the hip joint, for example, in which the head of the femur fits into the acetabulum. Another synovial joint is the hinged type as seen at the elbow, knee, or ankle joints. The bones of a synovial joint are separated by a capsule, composed of fibrous cartilage. Ligaments of connective tissue hold the bones together around the capsule to strengthen it. The bone surfaces at a joint are covered with a smooth surface called the articular cartilage. The synovial membrane is the inner layer of the capsule, the layer beneath the capsular surface. The synovial cavity is filled with a lubricating fluid produced by synovial membranes. This fluid contains water and nutrients that help to lubricate the joints so that friction on the articular cartilage is minimal. Bursae (singular bursa) are closed sacs of synovial fluid lined with synovial membrane. They lie in the spaces between tendons, ligaments, and bones and lubricate areas where friction would normally develop close to the joint capsule. The olecranon bursa at the elbow joint and the patellar bursa at the knee are examples of bursae.

Article / Updated 01-03-2020

Body parts and their accompanying medical terms don’t make a whole lot of sense until you can put them in the context of their general location within the body. Your body can be defined in several different ways, from groups and regions to cavities and planes. Body regions are used to specifically identify a body area. To illustrate all that’s involved with a body region, take a closer look at two major regions: the abdominal and spinal. The abdominal area is divided further into anatomic regions to diagnose abdominal problems with greater accuracy. Starting with the diaphragm, which is the muscle separating the thoracic cavity from the abdominal cavity, down to the level of the pelvis or groin, the abdominal area is divided into nine equal regions. Visualize the abdomen divided into nine squares: three across the top, three across the middle, and three across the bottom, like a tic-tac-toe board. The center portion is the umbilical region, the region of the navel or the umbilicus. Directly above this is the epigastric region, or the region of the stomach. Directly below the umbilical region is the hypogastric region. On either side of the epigastric region are the right and left hypochondriac regions. To the right and left of the umbilical region are the right and left lumbar regions. To the right and left of the hypogastric region are the right and left iliac regions. The anatomical divisions of the abdomen are referenced in anatomy textbooks to specify where certain organs are found. The clinical regions of the abdomen are used to describe the abdomen when a patient is being examined. The clinical regions of the abdomen divide the abdominal area, as above, into four equal quadrants: The right upper quadrant (RUQ) contains the right lobe of the liver, gallbladder, and parts of the small and large intestines. The left upper quadrant (LUQ) contains the left lobe of the liver, stomach, pancreas, spleen, and parts of the small and large intestines. The right lower quadrant (RLQ) contains parts of the small and large intestines, appendix, right ureter, right ovary, and fallopian tube. The left lower quadrant (LLQ) contains parts of the small and large intestines, left ureter, left ovary, and fallopian tube. Here’s a quick look at some of the smaller body regions, beginning at the head and moving downward. Region Where It Is Auricular region Around the ears Axillary Axillae (armpits) Buccal Cheeks of the face Carpal Wrist Cervical Neck Clavicular On each side of the suprastemal notch (small dip at top of the sternum) Infraorbital Below the eyes Infrascapular On each side of the chest, down to the last rib Interscapular On the back, between scapulae (shoulder blades) Lumbar Below the infrascapular area Mammary Breast area Mental Region of the chin Nasal Nose Occipital Lower posterior head Orbital Around the eyes Pectoral Chest Popliteal Behind the knee Pubic Below the hypogastric region (above the pubis) Sacral Area over the sacrum Sternal Over the sternum Submental Below the chin Supraclavicular Above the clavicles More body divisions are the regions of the spinal column, also known as the back. Note the difference between the spinal column (the vertebrae) and the spinal cord (the nerves running through the column). The spinal column is made of bone tissue, and the spinal cord is composed of nerve tissue. The spinal column is divided into five regions. Begin at the top and work downward: The cervical region (abbreviation C) is located in the neck region. There are seven cervical vertebrae, C1 to C7. The thoracic or dorsal region (abbreviation T or D) is located in the chest region. There are 12 thoracic or dorsal vertebrae, T1 to T12, or D1 to D12. Each bone in this segment is joined to a rib. The lumbar region (abbreviation L) is located at the loin or the flank area between the ribs and the hip bone. There are five lumbar vertebrae, L1 to L5. The sacral region (abbreviation S) has five bones, S1 to S5, that are fused to form one bone, the sacrum. The coccygeal region includes the coccyx, or tailbone, a small bone composed of four fused pieces. Check out the body’s anatomical positions and regions, planes, and cavities. Credit: Illustration by Kathryn Born It is important to remember that all these terms are for directional purposes only. They provide a road map to the body. Credit: Illustration by Kathryn Born In a medical examination, directional planes, regions of the abdomen, and divisions of the spinal column are used often by the examiner. Credit: Illustration by Kathryn Born

Article / Updated 03-26-2016

Most common medical terms used today are derived from Latin or Greek. After all, the Greeks were the founders of modern medicine. Examples of medical terminology used today based on the Greek language are The word semantics is derived from the Greek semantikos, meaning “significant.” Coccyx comes from the Greek word for “cuckoo” -- it resembles a cuckoo’s beak. Remember: myo (muscle) is not to be confused with myelo (bone marrow). Diaphoresis comes from the Greek dia meaning “through” and phoreo meaning “I carry.” Translated, it means “the carrying through of perspiration.” Glaucoma: Greek glaukos means “blue-grey,” and oma means “a condition.” In glaucoma, gray color replaces the black pupil. Both Latin and Greek play a role in the roots of the word for heart, cardium. This word stems from the Greek word kardia. Adenoid comes from the Greek aden, meaning “gland,” and cidos, meaning “like.” The term was once used for the prostate gland. Pancreas is so named because of its fleshy appearance. Greek pan means “all,” and krea means “flesh.” Endocrine: Take endo and add it to the Greek krinein, which means “to separate.” Paraplegia: The Greek para means “beside,” and plegia means “paralysis.” The Greek word pyelos means “tub-shaped vessel,” which describes the shape of the kidney. Venereal is derived from Venus, the goddess of love. It was thought in ancient times to be one of the misfortunes of love.

Article / Updated 03-26-2016

Don’t get discouraged studying medical terminology. A large group of medical terms are notorious for being difficult to spell. These medical terms are commonly misspelled: Abscess, adolescence, alimentation, alopecia, Alzheimer, analyze, aneurysm, anorexia, arrhythmia, ascites, asphyxia, asystole, auscultation, callus, catheter, Caucasian, chickenpox, cirrhosis, curettage, decubitus, diabetes mellitus, diaphoresis, diaphragm, dilatation, diphtheria, eczema, effusion, elicit, epididymitis, fascia, flaccid, gallbladder, gangrene, gauge, gonorrhea, hemoptysis, hemorrhoid, humerus, hygiene, icterus, inoculate, intraocular, intussusception, ischemia, melanin, menstruation, oophorectomy, ophthalmology, orthopnea, pacemaker, palliative, palpate, palpitation, perineum, periosteum, peritoneum, peroneal, prosthesis, prostate, protocol, pruritus, rhythm, sagittal, sedentary, sequela, sieve, spleen, splenectomy, supersede, syncope, syphilis, tonsils, tonsillectomy, tricuspid, ventricle, vertical, and xiphoid.

Article / Updated 03-26-2016

The root of a word is its main part and core meaning. These common medical root words give you a general idea of what you’re dealing with or specify a body part. Abdomin/o: Abdomen Aden/o: Gland Anter/o: Front Arteri/o: Artery Audi/o: Hearing Bio: Life Brachi/o: Arm Bronch/i, bronch/o: Bronchus Carcin/o: Cancer Cardi/o: Heart Col/o: Colon Cyt/o: Cell Derm/a, derm/o, dermat/o: Skin Dors/i, dors/o: Back or posterior Encephal/o: Brain Gastr/o: Stomach Gynec/o: Female Hemat/o: Bl ood Hist/o, histi/o: Tissue Intestin/o: Intestine Lapar/o: Abdomen, loin or flank Lymph/o: Lymph vessels My/o: Muscle Neur/o: Nerve Ocul/o: Eye Ophthalm/o: Eyes Optic/o, opt/o: Seeing, sight Or/o: Mouth Ot/o: Ear Path/o: Disease Pharmac/o: Drug Pulmon/o: Lungs Sept/o: Infection Thorac/o: Chest/thorax Thyr/o: Thyroid gland Trachel/o: Neck or necklike Trich/o: Hair or hairlike Ventr/i, ventr/o: Front of body Viscer/o: Viscera (internal organs)