Search Pattern Flashcards
What are the 2 errors of observation?
- Missing a significant finding (false negative)
- Identifying a normal variant as abnormal (false +)
What is an error of interpretation?
- Failure to link radiologic findings to clinical data
What are the ABCs of search patterns?
- Alignment
- Bone density
- Cartilage
- Soft tissues
What are the 3 categories of alignment?
- Skeletal architecture
- Contour of bone
- Alignment of adjacent bones
What are 4 types of skeletal architecture abnormalities?
- Aberrant size
- Extra (supernumerary) bones
- Absent bones
- Developmental deformities
What are 3 contour of bone abnormalities?
- Interal/ external irregularities
- Smooth/ cortical outline
- Spurs
What are 3 alignment of adjacent bone abnormalities?
- Fractures
- Dislocations
- Subluxations
What does aberrant size mean?
A structure is either too large or too small.
What can cause a false abberant size?
- Distortion caused by unequal distance from the image receptor
What is acromegaly?
- Increased size of structures due to extra production of GH.
What type of aberrant size does Paget’s disease cause?
- Increased trabeculae and cortical thickening
What is a fabella?
Pattela like bone on posterior knee.
What are 6 examples of supernumerary bones?
- Extra rays
- Extra distal phalanx
- Surgical rib
- Sesamoid bones within tendons (calcificaiton)
- Extra toes
- Extra phalanges in thumb
How is TO related to supernumerary bones?
- Surgical rib compresses brachial plexus, and vasculature.
What are two causes of absent bones?
- Congenital
- Post surgical
What are 2 examples of developmental deformities affecting alignment?
- Scoliosis
- Genu varum
What are 4 types of internal/ external irregularities related to alignment?
- Pathologic changes
- Traumatic injuries
- Developmental
- Congenital
What do breaks in the cortical outline indicate?
- Fracture
What are exostoses and spurs?
Spurs: osteophytes
Exotoses: calcification after a bleed
What is a Salter-Harris injury?
- Fracture that disrupts joint alignment
What are the differences between dislocations and subluxations?
Dislocation: No joint congruence
Subluxation: Partially congruent
What differentiates bone from soft tissue in a radograph?
Bone density.
What else does bone density help to differentiate?
- Cortical from trabecular bone.
How is the texture of trabeculae described?
- Descriptive term that lacks precise definition:
Ex)
- fluffy
- smudged
- coarsening
- lacy
What is sclerosis in relation to bone?
- Localized increase in bone density
What are 2 examples of excessive sclerosis?
- Normal fracture healing callus
- Abnormal calcification (OA)
What is reactive sclerosis?
- Body acts to surround and encapsulate an infection or tumor
What is the term for reactive sclerosis due to an infection?
Osteomyelitis.
What is a bony tumor called?
Osteosarcoma.
What is a sign that bone is growing too fast?
- The bone does not have a cortex.
What explains normal sclerotic processes?
Wolff’s law.
What are 3 elements of cartilage space?
- Joint space width
- Subchondral bone
- Epiphyseal plates
What is meant by the width of the joint space?
Width of the cartilage
When might there be an actual joint space?
During traction.
Which compartment of the knee has thicker cartilage?
The medial compartment.
What are 3 effects of increased sclerosis in subchondral bone?
- Loss of cartilage; linked with increased force through the joint (cause of, or caused by)
- Wears out bone
- Bony loss wears on cartilage
What are bony cysts?
- Erosion of bone
- Due to inflammatory arthritices
- Areas of round bony loss
What 3 characteristics of epiphyseal plates are evaluated in plain film?
- Position of primary and secondary growth centers
- Width of the plate
- Smoothness of the borders
What is difficult to evaluate in epiphyseal plates?
Fractures.
What alterations need to be made to evaluate soft tissue in plain film?
- Density
- Contrast
What are 6 soft tissue structures that may be examined on plain film?
- Muscles
- Fast pads/ fat lines
- Joint capsules
- Periosteum
- Gas
- Calcifications in soft tissue (myositis ossificans)
What causes myositis ossificans?
Bone formed in soft tissue due to deep bleeds/ bruises/ tears.
When may soft tissues become visible in plain film?
- When distended by intra-articular swelling
What are 4 types of periosteal changes that can be seen on plain film?
- Solid (due to fracture healing)
- Laminated (onion formation) due to repetitive injury
- Spiculated (malignant lesion)
- Codman’s Triangle (aggressive bone tumor)
What is codman’s triangle?
- Bony tumor
What are 7 categories of skeletal pathology?
- Congenital
- Inflammatory
- Metabolic
- Neoplastic
- Traumatic
- Vascular
- Other
What is an example of congenital skeletal pathology?
- Polydactylli (extra fingers)
- Club
- Coxa valga
WHat is an example of inflammatory skeletal pathology?
- RA
- Gout
What is an example of metabolic skeletal pathology?
- Osteoporosis
What is an example of neoplastic skeletal pathology?
- Osteosarcomas
- Osteophytes
What is an example of traumatic skeletal pathology?
- Bone fracture
What is an example of vascular skeletal pathology?
- Avascular necrosis (femoral head, scaphoid)
What are 11 variables that help diagnosis a skeletal lesion?
- Behavior (building, destroying)
- Bone or joint involved
- Locus within a bone
- Age, gender, and race of a patient
- Margin of the lesion (defined = better = slow growing)
- Shape of lesion
- Joint space crossed? (tumors don’t cross. Infections do)
- Bony reaction
- Matrix production (some tumors produce intracellular matrix)
- Soft tissue changes
- History of trauma or surgery
What can a margin of a bony lesion tell us?
If it is well defined, the lesion is slow growing.
Why might matrix production indicate the type of skeletal lesion?
Tumors can produce matrix.
What non bony changes can diagnose a skeletal lesion?
Soft tissue.
If a lesion crosses a joint space, is it a tumor or an infection?
An infection.
What census type data can help define a skeletal lesion?
Age, gender, and race.
What is meant by a skeletal lesion’s behavior?
- Building.
- Destroying
What features of the bone its self can help diagnose a skeletal lesion?
- The bone’s reaction to the lesion
- The location, and joint’s involved
- Where is lesion is focused/ spread through the bone (locus)
What can help diagnose a skeletal lesion during the patient interview?
- History of fractures
- Recent surgeries
