Bones -- Terminology
Canaliculi The canaliculi connect all bone cells to the nutrient supply, keeping the well-supplied in spite of their hard matrix material
Cartilage Tough connective tissue covering the ends of the bone. The cartilage reduce friction and acts as a shock absorber.
Condyle a rounded articular projection
Crest a narrow ridge of bone, usually prominent
Epicondyle a raised area on or above a condyle (see above)
Facet a smooth, nearly flat area
Fissure a narrow, slit-like opening
Foramen a round or oblong opening through a bone
Foramina Tiny canals in the bone through which blood and lymph vessels connect to the medullary.
Fossa a shallow, basin-like depression, often serving as an articular surface
Groove a furrow
Haversian canals central canals carrying the blood vessels and nerves. The Haversian canals run lengthwise through the bone
Haversian system each complex of a Haversian canal and it's matrix rings
Head a bony expansion carried on a narrow neck of bone
Hematopoiesis The formation of blood or blood cells in the body.
Lacunae tiny cavities arranged in concentric circles, called lamellae
Lamellae circles of lacunae and osteocytes about the central Haversian canal
Ligament Fibrous tissue that connects bones or cartilage to strengthen and support joints.
Line a narrow ridge of bone, but smaller and less prominent than a crest
Meatus a canal-like passageway
Ossification the gradual conversion of cartilage or other tissue into bone
osteoarthritis As the bone breaks down, bone spurs grow around the margins of the eroded cartilage that has been broken down. The bone spurs restrict movement (hands)
Osteoblasts build bone and secrete matrix, located on the surface
Osteoclasts break down bone and secrete alkaline phosphates, located on the surface of the bone
Osteocytes the mature bone cells, found in tiny cavities within the matrix called lacunae
Osteocytes mature bone cells found in the lacunae
Osteoporgenetors the only cell with mitotic potential, and can become osteoblasts. They are located in the inner periosteum, the endosteum, and blood vessel canals
Ramus an arm-like bar of bone
Rhumatoid arthritis causes chronic inflammation - The immune system attempts to destroy it's own tissues (joint cartilage), scar tissue forms & the ossifies causing defromation
Rickets a disease children get when the bones fail to calcify, causing bowing
Sinus a cavity within the bone, filled with air and lined by a mucosae
Spine a sharp, slender, often pointed projection
synovial fluid A clear, viscid lubricating fluid secreted by membranes in joint cavities, sheaths of tendons, and bursae.
Trochanter a very large, blunt, irregular process, found only on the femur, at the hip joint
Tubercle a small, rounded process
Tuberosity a large, rounded projection, sometimes rough in texture
Volkmann's canals-- the compliment to the Haversian canals, running at a right angle to them
appendicular skeleton bones of the limbs and girdles (shoulder & pelvic)
axial skeleton bones of the skull , vertebral column, ribs, and sternum

Types of Bone 
Compact bone Compact bone is dense and hard, especially the outer layer of the bone.
Spongy bone Made up of a lattice work of bone, the spaces are filled with red marrow which produce blood cells.
cuboidal box shaped
Flat bones Plate like and highly PROTECTIVE e.g. bones of the skull protect the brain.
Irregular bones e.g. vertebrae (spine)
Long bones Slightly curved for STRENGTH with long narrow shafts with knobbly ends (especially found in arms and legs e.g. femur).
sesmoid bones any of several small round (seedlike) bones formed in a tendon where it passes over a joint
Short bones Tend to be spongy e.g. wrists, fingers, toes and ankles.
sutural bones Small irregular bones found along the sutures of the cranium, particularly related to the parietal bone.
wormian bones small irregular plates of bone often interposed in the sutures between the large cranial bones.
Types of Breaks 
Simple the bone breaks cleanly, without breaking the skin; sometimes referred to as a closed fracture
Compound broken bone penetrates the skin; an 'open fracture', causes a serious threat of bone infection,
Comminuted bone breaks into many pieces; most common in the elderly, whose bones have become brittle
Compression bone is crushed; common in porous bones
Depression broken portion is pressed inward; typical of a skull injury
Impacted ends of the broken bone are forced together; occurs often when one attempts to use an outstretched hand to break a fall or in a hip fracture
Spiral broken by twisting; a common athletic fracture
Greenstick the break is incomplete; common in children, whose bones have a greater amount of collagen in their matrix and are more flexible
Parts of Bones 
diaphysis The shaft of a long bone.
Epiphysis The knob like end of the bone, often contains red marrow (blood cells).
epiphyseal plate growth plate - cartilaginous area where a majority of bone growth occurs - Metaphysis
Metaphysis Region where the diaphysis joins the epiphysis, important in bone growth - epiphyseal plate
medullary cavity Marrow cavity inside the bone. Contains yellow marrow (fat cells).
periosteum The dense fibrous membrane covering the surface of bones except at the joints and serving as an attachment for muscles and tendons
Articular cartilage cartilage that lines the joints
hyaline cartilage that forms most of the fetal skeleton and is found in the trachea, larynx, and joint surfaces of the adult.

Medical Terminology and Cancer
Copyright 1996-2000

Directional Terms 
Afferent impulses coming toward an area
anterior Situated in front of or in the forward part of, affecting the forward part; the ventral or belly surface of the body.
caudal Denoting a position more toward the tail(in animals) or buttocks (in humans) than some specified point of reference
Central Towards the center of the body
Cephalad toward the top
contralateral Pertaining to the opposite side
cranial Pertaining to the cranium or to the anterior (in animals) or superior (in humans) end of the body
Distal away from the main body or farthest from the starting point; Further away from the trunk.
dorsal Denoting a position more toward the back surface than some other object of reference, same as posterior in human anatomy, superior in the anatomy of quadrupeds.
Dorsum the upper most surface of the foot.
Efferent impulses going away from an area
frontal (coronal) Belonging to the front part; being in front
inferior Situated below another structure;The downward surface
lateral to the side; Away from the middle or away from the median plane.
Medial toward or closest to the midline or the median plane
Palmar On or towards the palm of the hand
Pelvic Pertaining to the pelvis.
Peripheral Towards the surface of the body
Plantar On or towards the sole of the foot
pleural Of or pertaining to the pleura or pleurae, or to the sides of the thorax.
posterior the back surface of the body and towards the back of the body. For example, the spine is posterior to the heart and the heart has a posterior surface.
prone Lying face downward.
Proximal towards the main body or closest to the point or origin
sagittal usually a plane- dividing the body into left and right halves
superior Situated above another structure;The upward surface
supine Lying on the back.
thoracic Pertaining to or affecting the chest.
transverse (horizontal) Lying or being across, or in a crosswise direction; athwart; often opposed to longitudinal.
ventral Denoting a position more toward the belly surface than some other object of reference, same as anterior in human anatomy.
Levels of structural organization 
1) chemical
2) cellular
3) tissue
4) organ
5) system
6) organism
median The plane which divides the body into a right and a left half; also called the saggital plane
saggital plane The plane which divides the body into a right and a left half; also called the median
coronal plane divides the body into a front and a back; at right angles to the saggital plane
frontal plane divides the body into a front and a back; at right angles to the saggital plane
horizontal plane divides the body into upper and lower portions; at right angles to both the frontal and saggital planes
transverse plane divides the body into upper and lower portions; at right angles to both the frontal and saggital planes

Don't be worried that there are 2 names for each plane ! You can use either name but you will find that certain people prefer to use only one name for each plane. There can be many saggital, frontal or horizontal planes. Planes are used to describe movement, for example, when you turn your head from right to left then your nose moves in a horizontal plane. When you bend forwards and backwards from the hips, your trunk moves in a saggital plane and when you lift your arm up out to the side of your body then your hand moves in a frontal plane. Planes are also used when describing sections through the body.
Flexion This movement takes place about a transverse axis and is a description of the movement that occurs when you lift your arm forward. It is described as the approximation (moving closer together) of two ventral surfaces of the body e.g. flexing the elbow joint, but there are a number of situations where this rule doesn't seem to apply e.g. at the ankle where the terms dorsi and plantar flexion are used to avoid confusion.
Extension This movement is the opposite of flexion, it also takes place about a transverse axis and occurs when you approximate two dorsal surfaces e.g. straightening the fingers or taking the arm backwards at the shoulder joint.
Abduction and Adduction These movements take place about an antero-posterior axis and occur when the arm is taken sideways away from the body (abduction) and returned from such a position to the side of the body (adduction). Another good example of this movement is abduction and adduction at the hip joint.
Rotation This movement takes place about a longitudinal axis. In the case of the shoulder joint this can occur about the longitudinal axis of the body when the arm is hanging by the side or it can occur about the longitudinal axis of the limb. For example, when the arm is abducted so that it is held straight out to the side it is still possible to produce rotation of the limb but in this case the axis is the longitudinal axis of the limb not that of the body (see diagram above).
Certain terns are used to describe the direction of rotation e.g. internal or external rotation and medial or lateral rotation. If rotation of the head or trunk are being described then right or left rotation are the terms used.
Spinal movements to the side or lateral movements are referred to as side flexion, side bending or lateral flexion to the right or left.
Circumduction This movement is a combination of Flexion/Extension/Abduction and Adduction of a long bone. It is usual to describe the movement as being similar to a cone, the base of the cone is described by the hand or foot with the apex being at the proximal end of the limb. In practice if you move your hand in a large circle moving from the shoulder joint you are performing circumduction.
Other terms commonly used
Inversion and Eversion These are terms used to describe movements of the foot, inversion occurs when you lift up the medial border of the foot with movement occurring at joints in the foot. Eversion occurs when the lateral border of the foot is lifted up. A certain amount of rotation occurs about a longitudinal axis through the foot.
Radial and Ulna deviation When the hand is abducted and adducted from the anatomical position it deviates towards the radial side of the forearm and the ulna side respectively. In order to avoid confusion regarding the definition of abduction and adduction when the arm is moved from the anatomical position, radial and ulna deviation are used to describe such movements at the wrist joint.
Dorsi and Plantar flexion At the ankle joint the movement of extension (lifting toes) is termed dorsi flexion and flexion (pushing toes down) is termed plantar flexion.
Supination and Pronation The forearm is able to rotate about its longitudinal axis so that, with the elbow flexed to a right angle it is possible for the hand to be placed palm up or palm down. With the palm up the forearm is supinated and with the palm down the forearm is pronated.
School of Health Professions and Rehabilitation Sciences     University of Southampton
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