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skeletal system

consists of bones, bone marrow, cartilage, joints, ligaments, synovial membrane, synovial fluid, and bursa


tough, fibrous tissue that forms the outermost covering of bone



compact bone

dense, hard, and very strong bone that forms the protective outer layer of bones

spongy bone

lighter, and not as strong, as compact bone. Commonly found in the ends and inner portions of long bones

medullary cavity

located in the shaft of a long bone and is surrounded by compact bone


tissue that lines the medullary cavity



red bone marrow

located within the spongy bone, is hemopoietic tissue that manufactures red blood cells, hemoglobin, white blood cells, and thrombocytes


pertaining to the formation of blood cells




pertaining to

yellow bone marrow

functions as a fat storage area, is composed chiefly of fat cells and is located in the medullary cavity


smooth, rubbery, blue-white connective tissue that acts as a shock absorber between bones.

articular cartilage

covers the surfaces of bones where they come together to form joints; makes smooth joint movement possible and protects the bones from rubbing against each other.


curved fibrous cartilage found in some joints, such as the knee and the temporomandibular joint of the jaw.


shaft of a long bone


covered with articular cartilage and is the wide end of a long bone.


opening in a bone through which blood vessels, nerves, and ligaments pass


normal projection on the surface of a bone that serves as an attachment for muscles and tendons


aka articulations, are the place of union between two or more bones.

fibrous joint

consisting of inflexible layers of dense connective tissue, hold the bones tightly together


aka soft spots; normally present on the skull of a newborn. These flexible soft spots facilitate passage of the infant through the birth canal

cartilaginous joint

allow only slight movement and consist of bones connected entirely by cartilage.

pubic symphysis

cartilaginous joint known that allows some movement to facilitate childbirth. Is located between the pubic bones in the front of the pelvis

synovial joint

created where two bones articulate to permit a variety of motions

synovial capsule

outermost layer of strong fibrous tissue that resembles a sleeve as it surrounds the joint

synovial membrane

lines the capsule and secretes synovial fluid.

synovial fluid

flows within the synovial cavity, acts as a lubricant to make the smooth movement of the joint possible


bands of fibrous tissue that forms joints by connecting one bone to another bone, or joining a bone to cartilage


a fibrous sac that acts as a cushion to ease movement in areas that are subject to friction such as the shoulder, elbow

axial skeleton

protects the major organs of the nervous, respiratory, and circulatory system

appendicular skeleton

makes body movement possible and also protects the organs of digestion, excretion, and reproduction


consists of the eight bones that form the cranium, 14 bones that form the face, and six bones in the middle ear


made up of the following eight bones, is the portion of the skull that encloses the brain



frontal bone

forms the forehead

parietal bone

form most of the roof and upper sides of the cranium

occiptial bone

forms the posterior floor and walls of the cranium

temporal bone

form the sides and base of the cranium

sphenoid bone

forms part of the base of the skull and parts of the floor and sides of the orbit

ethmoid bone

forms part of the posterior portion of the nose, the orbit, and the floor of the cranium

auditory ossicle

six tiny bones of the middle ear

external auditory meatus

located in the temporal bone on each side of the skull; is the opening of the external auditory canal of the outer ear

nasal bones

form the upper part of the bridge of the nose

zygomatic bones

aka cheekbones, articulate with the frontal bone

maxillary bones

aka maxillae, form most of the upper jaw

palatine bones

form part of the hard palate of the mouth and the floor of the nose

lacrimal bone

make up part of the orbit at the inner angle of the eye

inferior conchae

thin, scroll-like bones that form part of the interior of the nose

vomer bone

forms the base of the nasal septum


aka jawbone; only movable bone of the skull

temporomandibular joint

where the mandible is attached to the skull

thoracic cavity

the bony structure that protects the heart and lungs


aka costals


aka breastbone; forms the middle of the front of the rib cage and is divided into three parts


bony structure that forms of the upper portion of the sternum

body of the sternum

bony structure that forms the middle portion of the sternum

xiphoid process

structure made of cartilage that forms the lower part of the sternum

pectoral girdle

supports the arms and hands; aka shoulder girdle


aka collar bone; a slender bone that connects the manubrium of the sternum to the scapula


aka shoulder blade


an extension of the scapula that forms the high point of the shoulder


bone of the upper arm


smaller and shorter bone in the forearm; runs up the thumb side of the forearm


larger and longer bone of the forearm

olecranon process

aka funny bone; a large projection on the upper end of the ulna; forms the point of the elbow and exposes a nerve that tingles when struck


bones that form the wrist


five bones that form the palms of the hand


14 bones of the fingers


bony structure units of the spinal cord

cervical vertebrae

first set of seven vertebrae that form the neck

thoracic vertebrae

make up the 2nd set of 12 vertebrae and form the outward curve of the spine

lumbar vertebrae

make up the 3rd set of five vertebrae and form the inward curve of the lower spine


slightly curved, traingular-shaped bone near the base of the spine that forms the lower portion of the back.


aka tailbone; forms the end of the spine and is actually made up of 4 small vertebrae that are fused together

intervertebral disks

made of cartilage, separate and cushion the vertebrae from each other. they are shock absorber and allow for movement of the spinal cord

pelvic girdle

protects internal organs and supports the lower extremities; aka pelvic or hips


broad blade-shaped bone that forms the back and sides of the pubic bone


slightly movable articulation between the sacrum and posterior portion of the ilium




forms the lower posterior portion of the pubic bone, bears the weight of the body when sitting


forms the anterior portion of the pubic bone, is located just below the urinary bladder

pubic bones

formed by the ileum, ischium, and pubis


aka hip socket; large circular cavity in each side of the pelvis that articulates with the head of the femur to form the hip joint


upper leg bone; aka thigh bone; the largest bone


complex joints that make possible movement between the upper and lower leg


aka kneecap; bony anterior portion of the knee


referring to the posterior space behind the knee where the ligaments, vessels, and muscles related to this joint are located

cruciate ligaments

make possible the movements of the knee


aka shinbone; larger, weight-bearing bone in the anterior of the lower leg


smaller of the two bones of the lower leg


rounded bony protuberance on each side of the ankle


form the joint between the lower leg and the foot and each are made up of 7 tarsal


7 of them make up the ankle


anklebone that articulates with the tibia and fibula


aka heel bone; largest of the tarsal bones


form that part of the foot to which the toes are attached


bones of the toes


holds a doctor of chiropractice degree and specializes the manipulative treatment of disorders originating from misalignment of the spine

orthopedic surgeon

aka orthopedist, is a physician who specializes in diagnosing and treating diseases and disorders involving the bones, joints, and muscles


holds a doctor of osteopathy degree and uses traditional forms of medical treatment in addition to specializing in treating health problems by spinal manipulation


holds a doctor of podiatry and specializes in diagnosing and treating disorders of the foot


loss, or absence, of mobility in a joint due to disease, injury, or surgical procedure


crooked, bent, or stiff


stiffness of the joints, especially in the elderly


inflammation of a bursa




abnormal softening of cartilage


a slow-growing benign tumor derived from cartilage cells


inflammation of the cartilage that connects a rib to the sternum



hallux valgus

aka bunion; an abnormal enlargement of the joint at the base of the great toe


blood within a joint due to a joint injury but can also occur spontaneously in patients taking blood-thinning medication or those having a blood clotting disorder


inflammation of the synovial membrane that results in swelling and pain of the affected joint


aka luxation; total displacement of a bone from its joint


partial displacement of a bone from its joint


inflammatory condition of one or more joints


aka wear-and-tear arthritis; is most commonly associated with aging


aka spinal osteoarthritis; degenerative disorder that can cause the loss of normal spinal structure and function



gouty arthritis

aka gout; a type of arthritis characterized by deposits of uric acid in the joints

rheumatoid arthritis

abbreviated as RA; a chronic autoimmune disorder in which the joints and some organs of other body systems are attacked.

ankylosing spondylitis

form of rheumatoid arthritis that primarily causes inflammation of the joints between the vertebrae


progressive stiffening of a joint or joints

juvenile rheumatoid arthritis

autoimmune disease that affects children aged 16 years or less with symptoms that include stiffness, pain, joint swelling, skin rash, fever, slowed growth, and fatigue

herniated disk

aka slipped or ruptured disk; breaking apart of an intervertebral disk that results in pressure on spinal nerve roots


aka low back pain; is pain of the lumber region of the spine


disease conditioned


forward slipping movement of the body of one of the lower lumbar vertebrae on the vertebra or sacrum



spina bifida

congenital defect that occurs during early pregnancy when the spinal canal fails to close completely around the spinal cord to protect it.


abnormal increase in the outward curvature of the thoracic spine as viewed from the side


abnormal increase in the forward curvature of the lumbar spine


bend backward


abnormal lateral (sideways) curvature of the spine




malformation of the skull due to the premature closure of the cranial sutures

fibrous dysplasia

bone disorder of unknown cause that destroys normal bone structure and replaces it with fibrous (scar-like) tissue and leads to uneven growth, brittleness, and deformity


aka osteodynia; main pain in a bone


aka ostitis; inflammation of bone


aka adult rickets; abnormal softening of bones in adults and is caused by a deficiency of vitamin D, calcium, and/or phosphate


inflammation of the bone marrow and adjacent bone


bone marrow


death of bone tissue to a lack of insufficient blood supply

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