Basics of MSK Radiology (Bennett) Flashcards
gold standard for diagnosis of osteoarthritis
radiography
All of the following are features of osteoarthritis EXCEPT:
A. Uniform joint space narrowing
B. Osteophyte formation
C. Subchondral sclerosis
D. Weight bearing joints affected
E. Subchondral cysts
A. Non-uniform joint narrowing is what’s seen in OA
What feature is seen on the radiograph below?
subchondral cysts
Which of the following is NOT a hallmark of rheumatoid arthritis?
A. Symmetric bilateral proximal involvement of the hands
B. More common than osteroarthritis
C. Shows fusion of carpals and joint subluxation
D. Uniform joint space narrowing
E. Periarticular (darker on radiography) osteopenia
B
Why is joint space narrowing uniform in RA?
this is due to an autoimmune process that results in digestion of cartilage
With MSK trauma, you should always start with what type of imaging?
plain films, two perpendicular views
type of fracture?
oblique
type of fracture?
buckle
*notice the bump on the lateral edge of the radius
type of fracture?
pathologic; the dark circle is a tumor
type of fracture below, correlated with diabetes:
alvusion fracture (CIA fracture)
type of fracture?
intra articular fracture (a fracture that extends into the joint space - ex, salter harris type III and IV)
type of fracture?
greenstick fracture
type of fracture?
spiral (toddler) fracture
pediatric Salter-Harris fractures that are most likely to have a physeal bar
Salter-Harris type IV and V
*A physeal bar or partial premature physeal arrest is a result of injury or infection to an unfused physis. It consists of a bony bridge crossing the growth plate that results in growth disturbance and/or deformity
type of Salter-Harris fracture indicated by black arrow?
type III (fracture is below the physis, as indicated by the lighter arrow)
type of Salter-Harris fracture?
type I (slipped)
type of Salter Harris fracture?
type IV - goes through both the metaphysis and epiphysis
3 types of injury highly associated with non-accidental trauma
- bucket handle fracture (wisps of bone coming of the metaphyseal corners)
- periosteal hemorrhage
- multiple fractures of varying ages
radiographic signs of this include destruction of bone, periosteal reaction, tissue swelling, and abscess formation
osteomyelitis
formation of new bone in response to injury or other stimuli
periosteal reaction
what does soft tissue gas on an xray indicate?
fulminant infection such as gangrene with a gram negative rod that is gas producing; has a mottled or linear appearance on x-ray
osteomyelitis may spread hematogenously, with seeding in the ____ metaphysis where blood flow is the slowest
distal
what adult population is direct implant osteomyelitis associated with?
diabetics
most sensitive and specific test for osteomyelitis
MRI
*although plain film is used first and is considered the gold standard for diagnosing osteomyelitis, signs often do not appear for a week or more. MRI can pick up signs of OM in 24-48 hours of onset)
In a patient who is 40 or older and the radiograph shows a lytic dark bone tumor proximal to elbows or knees what will the diagnosis be 99% of the time?
either metastasis or multiple myeloma
A 49 year old woman presents with pain in the knee. After doing a H&P you believe she may have osteoarthritis and you order an xray. The film shows a dark lytic bone lesion proximal to the knee. What is the next step you would take in confirming this woman’s diagnosis?
this is likely multiple myeloma or a metatasis. since metastasis occurs the majority of the time from breast or lung in this patient population, you would order a chest xray and do a breast exam and/or order a mammogram
wispy projections that look like hair coming off the bone indicates what?
osteosarcoma
