_______'s are ultimately responsible for the radiology diagnosis. PT's may need information not on the written report and being ablt to analyze the image itself will improve treatment planning and outcome.
What does the book say about the benefits of viewing diagnostic images:
-1. A more comprehensive evaluation can be obtained. Imaging provides an objective, visual component to the evaluation.
- 2. The info a PT is looking for may be different than what the physician is looking for. (For example a fixation screw that is holding the bone together but may be limiting joint ROM)
When are diagnostic tests indicated?
1. Sometimes pt. history, systems review and/or tests and measures make it evident.
2. In the "absence of appropriate response to PT intervention"
3. "If response is not consistent with the prognosis"
4. "Imaging studies are normally indicated only when positive findings will influence decision making."
When are diagnostic tests NOT indicated?
1. "Injury responds consistent with expected prognosis"
2. If diagnosis suggests surgical intervention but pt is unwilling or is a poor candidate for surgical intervention.
What PT's use imaging for? (intervention planning)
1. assess bony alignment
2. identify bony blocks to movement
3. visualize exact location of fractures to plan interventions
4. identify exact position of fixation devices
5. assess bone healing to make decisions about movement and weight-bearing
-Ionizing radiation passed through the body, _______ through tissue based on its radio-density and is captured on an image receptor.
-Can distinguish air, bone, calcification, fat, soft tissue and fluids
-Ionizing radiation is potentially _____ to cells. Need to limit excess exposure through correct positioning, shielding, and only performing necessary imaging.
Plain Radiographs are Good for the following:
1. demonstrate bone origin pathology, relationship of bone structures,
or the relationship of foreign objects to the skeletal structures.
2. Demonstrate fine cortical and trabecular detail of bone (benign and malignant neoplasm infections)
3. Distinguishes calcification patterns
4. Detecting avulsions and simple to complex fractures
Plain radiography are NOT GOOD for:
1. early detection of stress fractures (may take up to 6 weeks)
2. limited sensitivity for early tumors or infections
3. limited detail for diagnosis muscle, ligament or tendon injury
________: Dynamic or continuous radiographic examination--like a radiographic movie. Allows viewing of physiological function or medical procedure in real time. Used for examinations and procedures such as barium-xrays, cardiac catheterization, placement of IV catheters, image guided injections, and image guided surgical techniques.
______: injection of contrast into blood supply to find obstructions or abnormalities
______: injection into specific artery to demonstrate blood flow
____ ____: shows upper GI tract
______: contrast material injected into joint. May be used with other media such as MRI and CT.
______: contrast material injected into subarachnoid space to look at spinal cord, nerve roots and dura mater.
_____ ______: x-ray tube and data processing unit rotate 360 deg around stationary patient creating cross sectional images. Exposes patient to higher doses of ionizing radiation but is confined to smaller areas. Images have higher resolution than plain radiographs.
CT GOOD for:
1. Effective at defining cortical and trabecular bone
2. provides good detail of spinal segments showing osteophytes and spinal fractures such as stress fractures of pars interarticularis of burst fractures of vertebral bodies.
3. May be ordered when radiographys are normal but patient examination strongly suggests fracture
4. Less complex/expensive than MRI
CT is BAD for:
1. Higher dose of radiation/more expensive than conventional radiographs
2. Limited ability to differentiate between types of soft tissue
______ ______ ______ ______ ______ (SPECT): can localize small abnormalities; used to study bone, cardiac perfusion, brain, and liver.
______ _______ ______: Shows normal and abnormal biological function of cells; used in cardiology, neurology and oncology to detect and stage tumors.
Single Photon Emission Computed Tomographry
Positron Emission Tomography
___________ (Radionuclide Bone Scan): radiopharmaceutical substance is injected into patient hours before the bone scan; The scan reveals areas of increased radionuclide uptake in the skeletal system, and "designates areas of hyperfunction, or increased mineral turnover." Areas with the most uptake appear as dark or "hot" spots. These areas of increased metabolic activity may be "bone attempting to heal after a fracture or responding to neoplasm or infection."
Scintigraphy: Radionuclide Bone Scan
______ ______ ______: Uses radio frequency waves (not ionizing radiation) in a magnetic field to create images of both bone and soft tissue.
Body tissues are exposed to a radio frequency (RF) pulse that produce measurable changes in the body's atoms. The atoms (typically hydrogen) align in the direction of the magnetic field. When the RF pulse is stopped the energy absorbed is released as an electric signal that creates digital images.
Magnetic Resonance Imaging
_______ produces high quality images of large joint components, such as fibrocartilage, ligaments, capsules, and synovium as well as small joints and fine soft tissue structures.
With contrast added can increase diagnosis of rotator cuff tears, labral tears, or articular cartilage injuries. Also effective to diagnose muscle tear and to monitor healing of soft tissues.
____ is shown to be superior to ___ at delineating combinations of multiple soft tissue and osseous insults.
____ is better at showing bone marrow abnormalities than ___.
MRI superior to CT
MRI better than CT
_____ suggested to be gold standard in detecting bone stress injuries.
___ weighted MRI:
Subacute hemorrhage and fat have characteristic bright signal intensity. Bone also appears bright due to its high fat content. Other soft tissue has low signal intensity.
-Good for revealing details of anatomy as the "clearly delineate the architecture of a variety of soft tissue structures.
T1 weighted MRI
___ weighted MRI: fluids have a high signal intensity. Fluids and fluid containing structures such as bursae, inflamed tendons, tumors and abscesses have a high signal intensity.
____ reveal less detail in soft tissue structures than ___.
T2 reveal less detail in soft tissue than T1
MRI absolute contraindications:
Ferro magnetic implants or objects
MRI relative contraindications:
1. pt. intolerance to claustrophobia
2. inability of patient to remain motionless
_______: images generated by tissues reflecting sound waves. Non-ionizing, non-invasive, inexpensive, and convenient.
Effective at imaging superficial soft tissue structures such as muscle, tendon, ligament, nerve and foreign bodies. Also detection of cysts, soft tissue tumors and measurement of blood flow.
T or F: Quality of image lowly dependant on skill of examiner
T or F: More useful on thin patients.
T or F: Bone and metal reflect the sound and are adequately imaged.
False: non adequately imaged
Alignment: 3 things
1. general skeletal architecture: size and number of bones
2. general contour: irregularities, cortical outline, spurring, breaks in cortex, surgical markings
3. alignment of bones and joint position: fracture, dislocation, subluxation
________: not easily penetrated by x-rays.
________: easily penetrated by x-ray beams
Radiodensity from most radiolucent to radiopaque:
1. air (black)
2. fat (grays-black)
3. water (gray)
4. bone (white)
5. contrast medium/heavy metals (bright white)
Thicker equals (increased or decreased?) radiodensity relative to thinner objects of the same substance.
How many views are necessary for x-rays?
2 at a minimum at 90d to each other are necessary to view object in 3 dimensions and avoid missing important details.
RAdiographs are orienteds as if the patient is in ______ position facing the viewer.
Hands and feet are viewed with the digits pointing ______.
Lateral projections placed so image is seen from perspective of the _______.
______ bone: dense, outer layer of bone that provides strength to long bones.
_____ bone: spongy, inner bone that provides supportive cushioning.
______ _____: becomes visible when distended by effusion. Intra-articular fractures produce different types of effusion.
__________: mixture of fat and blood from bone marrow enter joint space through break in bone.
______-____ _____ sign: fat floats on surface of blood. This interface can be seen on radiograph and should alert you to intra-articular fracture.
fat-blood interface sign
Periosteum: 4 types of abnormal reactions
1._____: benign process,fx healing and osteomyelitis
2._____: repetitive injury (battered child syndrome), or sarcoma
3._____: malignant bone lesion
4._____: tumor, subperiosteal hemorrhage, battered child syndrome
laminated or onion skiin
spiculated or sunburst
Margins of Lesions:
-Sharp, clearly defined sclerotic borders characteristic of slow growing or ____ lesions.
-Wide, poorly defined borders with minimal or absent reactive sclerosis characteristic of fast growing or ______ lesions.
True or False: Tumors, benign or malignant, do not cross joint spaces or epiphyseal grownth plates, but inflammatory processes cause destruction of bone on both sides of the joint
______: bone growth to fortify an area subjected to increased stress
______: formation of boney exostosis or osteophytes to strengthen architecture of joint.
______ _______: spontaneious exacerbations of bilateral and symmetrical joint inflammation, hyperplasitc synovitis, resultant cartilage and bone destruction and consequent loss of function.
Early stages of RA involve what joints:
Later stages cause what:
small joints of wrists, and hands and feet
joint deformities, contractures and ankylosis
ABCS's of Radiologic findings of RA
A: bilateral joint involvment; MCP subluxation and ulnar deviation, swan neck and boutonniere deformity of IP's; dislocation in later stages; acetabular profusion of hip
C: symmetrical, concentric joint space narrowing, subchondral erosions, subchondral systs
S: periarticular swelling, fusiform swelling
ABCS: of OA
A: unilateral involvement of synovial or cartilaginous joints; heberden's nodes DIP, bouchards nodes PIP, valgus or varus at knees, subluxations and joint misalignment
B: usually absence of osteoporosis
C: asymmetric, irregular joint space narrowing, sclerotic subchondral bone, osteophytes at joint margins, subchondral cysts, intra-articular loose bodies
S: joint effusion during acute exacerbations
_____ fx: breaks through skin
_____ fx: skin is intact
_____ fx: 2 or more fragments
_____ fx: contact between bones
Type_: a complete physeal fx with or without displacement
Type_: a physeal fx that extends through the metaphysis
Type_: a physial fx that extends through the epiphysis
Type_ : a physeal fx plus epiphyseal and metaphyseal fx
Type_: a compresison fx of growth plates
Salter harris fx
Most common sites of traumatic injury to C-spine is __-__ and __-__.
______ fx can appear normal on radiography 20% of the time
_____ ____ fx's some patients can bear weight despite fx.
____ _____: Combo of x-ray and computer technology to make detailed cross sectional images of body. Able to separate layers to allow viewing of specific structures or tissue. Accurately shows small lesions.
-Axial images are viewed as if looking up from _____ patient's feet.
Radiodensities can be altered to distinguish betweeen tissues of similar density.
10 good things about CT
1. best for _____ (subtle or complex)
2. best for eval of ______ changes
3. May be 1st in ______ injuries.
4. Excels in eval of _____ _____ (especially with myelography)
5. Combined with diskogram gives invaluable info on ____.
6.Best modality for eval of _____ ____ in joint.
7. Less ____ ____ than MRI or US.
8. Allows accurate measurement of ______ alignments in any planes.
9. CT less ____ than MRI.
10. Easier on ______ patients.
3.trauma (to bone and soft tissue)
4.spinal stenosis (especially with myelography)
7. time consuming
8. osseous alignment
Limits of CT:
1. Limited capabilitities in differentiating between tissues with similar _______.
2. Relatively _____ ______ exposure.
high radiation exposure
______: uses magnetic field and radiofrequency signals to cause hydrogren nuclei to emit a signal that is captured and converted to an image by computer.
-the hydrogen nuclei in different tissues gives off different signals
Explain the process of MRI:
1. pt. put in ____ with strong ____.
2. all the ____ in the pt ar lined up like bar magnets (longitudinal magnetization)
3. A radiofrequency wave pulse is emitted and it knocks the ______ into an alignment to a _______ plane and they absorb the energy from the pulse (______ magnetization)
4. After the pulse the _____ realign and release the energy absorbed from the pulse. This creates a current in a receiver coild and image is made from data.
2 important components of MRI sequencing:
1. ____ to _____: time at which RF pulse is repeated to again displace protons
2. ____ to _____: time at which the signal is captured
time to repetition (TR)
Time to echo (TE)
___ MRI has a short repetition time (TR) and short echo time (TE). This makes ____ and subacute ____ bright and ___ and ____ ____ dull.
*good for showing anatomical detail
fat and subacute hemorrhage
fluid and soft tissue
__ MRI has a long TR and long TE which makes ____ and ___ filled structures bright.
Fluid and fluid filled
_____ _____ weighted MRI: combine T1 and T2 weighted images to minimize differences. Produce good anatomic detail with little tissue contrast. Favor water and fat tissues and are often used to evaluate orthopedic trauma.
Proton Density Weighted MRI
Viewing MRI images (similar to CT)
1. Coronal images viewed from ___ as if facing pt.
2. Axial viewed from below as if looking at pt. _____>
3. Sagittal viewed from __ to __ for either side of the body
L to R
MRI is good at:
1. detecting changes in _____ _____.
2. Displaying ____ ____ detail.
3. Has replaced ______ diagnostic procedures.
4. Best at diagnosing ______ ______.
5. Able to stage ____ in bone and soft tissue.
soft tissue (distinguish tendon and ligament)
Disadvantages of MRI:
1. Take too much ____
2. Too ____.
3. Contraindications with ______ and ______ patients.
Advantages of MRI over CT:
1. Greater contrast resolution for _____ _____ imaging.
2. Greater ability to image ____ surrounded by bone
3. No ______
4. Less risk for missing ____ processes.
______ ___: diagnostic imaging modality that can be applied to patient in real time as part of exam. Able to use while applying physical exam techniques. Uses frequences in the range of 3.5-15 MHz. Creates a mechanical wave that travels via particle vibration (callled _____ ______). How for this wave travels dependos on trength of sound source, the properties of the media through which the sound has to travel.
_______: Ability of sound to travel (depth). As intensity is increased, depth increases, strength of echo increases, and potential to generate biological effects increases with tissues.
________: US wave changes as it encounters tissues, occurs through process of reflection, scattering, refraction and absorption.
______: US imaging is based on collection of reflected sound.
1. Acoustic _____- increase in amplitued of US echo coming from structure that lies behind a weakly attenuating surface such as a fluid filled cavity (bladder).
2. Acoustic _____: opposited of _____. Sound wave echo reduces behind strong, attenuating structure (bone).
3. _______: refers to multiple reflections and is result of US echoes bouncing between tissue layers and the transducer.
_______: tissues that reflects much energy. Waves reflected off ______ structures produce bright images (e.g.: cortical bone, tendons, ligaments)
_______: tissue that reflects little energy. Waves reflected off _____ structure produce dark images (e.g.: bone, fat)
Advantages of US:
1. _____ resolution
2. low ____ and easy _____
3. no known _____
4. Can compare non_____ limb
5. put affected limb in ______ provoking position
6. perform ____ or ____ to find a tear
7. apply ____ or ____
8. _____ test ligaments
9._____ for tenderness and apply probe over area
1. higher resolution
2. low cost and portability
3. no known hazards
4. ready comparison of opposite side
5. put affected joint in symptom provoking position
6. perform MMT or stretching to find tear
7. apply traction or compression
8. stress test ligaments
9. palpate for tenderness and apply probe over area
Disadvantages of US:
1. Limited ability to show _____ _____ and _____-_____ structures.
2. only shows ____ outline of bone.
3. Does not cross ____ filled surfaces (lungs)
4. ______ dependent
5. ______ patients not imaged well
6. ______ is not imaged well
1. joint surfaces and intra-articular structures
2. cortical outline
3. air filled
4. operator dependent
5. obese patients
Good uses for US:
_____ and ____-_____ structures
_____ ___ and ______ tendons