Ch. 2 - Bones And More Positions Flashcards
How many bones in the body?
206
The skeleton is decided into two main groups, what are they?
Axial skeleton and appendicular skeleton
Axial skeleton
Supports and protects the head and trunk, comprised of 80 bones
Appendicular skeleton
Provides means of movement, comprised of 126 bones
Periosteum
Outer, denser lay of the bone, tough, fibrous connective tissue that covers bone except at the articular ends
Endosteum
Lines marrow cavity
Trabeculae
Speculated network filled with red and yellow bone marrow
Red marrow
Produces white and red blood cells
Yellow marrow
Stores fat cells
Medullary cavity
Central cavity of long bones, contains trabeculae with yellow marrow, red marrow found at the ends of long bones
Ossification
The development and formation of bones, begins in the second month of embryonic life
Primary ossification
Begins before birth and forms long central shaft in long bones
Secondary ossification
Begins after birth when separate bones begin to develop at both ends of long bones (the ends are called epiphyses)
Epiphyses
The separate bones developed after birth at the ends of long bones
5 classifications of bones
Long, short, flat, irregular, sesamoid
Long bones
Have a body and two enlarged articulate ends,found only in limbs
Examples: femur, radius, ulna, fibula, tibia, humerus
Short bones
Consist mainly of cancellous bone with a thin outer layer of compact bone
Examples: tarsals, carpals
Flat bones
Consist of two plates of compact bone, middle layer of cancellous bone called diploe
Examples: skull, scapula
Irregular bones
Peculiarly shaped
Examples: spine
Sesamoid bones
Very small and oval, develop inside and beside tendons, protect the tendon from excessive wear
What is the largest sesamoid bone?
Patella
3 bone markings and features
Processes or Projections, depressions, fractures
Bone Processes and projections
Extend beyond or project out from the main body of the bone
Bone functions
Attachment for muscles, mechanical basis for movement, protection of internal organs, support frame for the body, stores calcium phosphorus and salts, production of red and white blood cells
Bone Depressions
Hollow or depressed areas
Bone fractures
A break in a bone
Condyle
Rounded process at an articulate end
Ex: distal end of the femur
Coracoid or coronoid
Beaklike or crownlike process
Ex: on the shoulders or elbows
Crest
Ridgelike process
Ex: pelvis (iliac crest)
Epicondyle
Projection above a condyle
Head
An expanded end of a long bone
Ex: femoral head
Malleolus
Club shaped process
Ex: fibula and tibia
Protuberance
Projecting prominence
Ex: occipital protuberance
Styloid
Long pointed process
Ex: radius, ulna
Trochanter
Either of the two larger, rounded, and elevated processes of the proximal femur
Tubercle
Small rounded and elevated process
Ex: proximal end of the humerus
Tuberosity
Large, rounded, elevated process
Ex: anterior superior iliac spine (bump on front side of hip)
Foramen
Hole in a bone for transmission of vessels and nerves
Ex: foramen magnum
Fossa
Pit or hollow space
Ex: glenoid fossa
Meatus
Tubelike passageway
Ex: auditory meatus
Sinus
Recess, groove, cavity or hollow space
Ex: maxillary, sphenoid, frontal, and ethanoid
How can fractures be describe?
Open or closed
And displaced or nondisplaced
Fracture classifications
Compression, compound, simple, greenstick, transverse, spiral or oblique, comminuted, impacted
Simple fracture
Straight break
Greenstick fracture
Not broke all the way through bone, usually seen in children
Transverse fracture
90 degree break
Spiral/ oblique fracture
Broke at an angle
Comminuted fracture
Shattered bone
Impacted fracture
Bone shoved into itself
3 types of motion when imaging..
Involuntary, voluntary, equipment
Involuntary motion
Heartbeat, chills, perstalsis, remor, spasm, pain
Primary control for involuntary motion?
Exposure time
Voluntary motion
Nervousness, excitability, discomfort, mental illness, fear, age, breathing
How to control voluntary motion?
Give clear instructions, provide patient comfort, add or adjust support devices, apply immobilization, decrease exposure time
Required information for an image ID?
Date, patients name, medical record, right or left marker, institution identity
How are radiographs viewed?
In the anatomical position
Lateral radiographs
Generally viewed from the same orientation as if looking at the patient from the perspective of the X-ray tube, use the marker for whatever side is closest to the IR
Oblique radiographs
Generally viewed from the anatomical position
IR placement
Longitudinal, horizontal, corner to corner
Central Ray
CR - the central or principle beam of Rays, always centered to the image receptor, the CR is perpendicular to the IR
Why angel the CR through a point of interest?
To avoid superimposition of structures, to straighten out curved structure, to align the CR through an angled joint space,to avoid distortion of an angled structure
What is it called when the central ray is angled towards the head?
Cephalad
What is it called when the central ray is angled towards the feet?
Caudad
Collimators?
Are used to limit and adjust the size of the X-ray field
Why collimate?
Reduces: patient radiation dose, scatter radiation
Increases radiographic contrast
Prevents secondary radiation from unnecessarily xposing surrounding tissues
Shielding guidelines for the gonads..
Shield when gonads lie close or within the X-ray field, hen clinical objective is not compromised, and when he patient is at reproductive potential
Projection
Defined as the path of the beam s it exits the X-ray tube, passes through the patient to the IR
Position
Overall posture of the Agilent or general body position, also refers to the specific placement of the body or part in relation to the table or IR
View
Used to describe the body part as seen by the IR
Method
Refers to a specific radiographic projection developed by an individual
Essential projections
PA, AP, Axial, Tangential, lateral, oblique
AP
The CR enters the anterior surface and exits the posterior
PA
The CR enters posterior surface and exits the anterior
Axial
Longitudinal angle of the CR of 10 degrees or more
Tangential
CR directed around the outer margin of a curved body surface
Lateral
CR enters one side of the body, passing transversely along the coronal plane
Oblique
CR enters from side angle (exit and entrance is specific ex: AP oblique)
General body positions
Upright, seated, recumbent, supine, prone, lateral position
Recumbent
Laying down
Supine
On back
Prone
On stomach
Oblique position
Body is rotated, coronal plane is not parallel with the IR, it is named according to the side and surface of the body closest to the IR,
Ex: RPO - right posterior oblique
Decubitus position
Alternative to standing, recumbent position with a perpendicular CR, named according to the body surface on which the patient is lying
Lordotic position
Upright position in which the patient is leaning backward, this is used in a chest X-ray when the clavicles are in the way
Special positions
Trendelenburg’s, Fowler’s, Sim’s, Lithotomy
Trendelenburg’s position
Supine with the head lower than the feet
Fowler’s position
Supine with head elevated
Sim’s position
Recumbent with the patient lying on the left anterior side with left leg extended and right knee and thigh partially flexed, used when giving a barium enema
Lithotomy position
Supine with knees and hips flexed and thighs abducted and rotated externally, supported by ankle supports, not used very much
