MSK Flashcards
Risk factors of hip AVN
- subcapital femoral neck fracture
- delayed reduction in posterior hip dislocation
- steroid
- alcoholism
- Cushing’s disease
- sickle cell disease
- SLE
- Gaucher’s disease
- Caisson disease
- radiation
ball-catcher’s view
ball-catcher’s view
good for profiling the triquetrum and pisiform
Most earliest site of involvement in Charcot’s joint
Talonavicular joint
Causes of Charcot’s joint
- foot - diabetes
- knee - tabes dorsalis
- shoulder - syringomyelia
- spine neuropathy - spinal cord trauma
Psoriatic arthritis vs Reiter’s
- Psoriatic arthritis - both erosive and productive
- Reriter’s - mainly erosive
6D’s for Charcot joint
- destruction
- disorganization
- dislocation
- distention
- debris
- density increase
Primary hypertrophic osteoarthropathy
- a spectrum of diseases ranging from mere periostitis to the complete process of periostitis, clubbed digits, and thickening of the skin (facial and hands).
- often familial and is much more common in males than in females.
- onset is in adolescence, and there is usually spontaneous arrest of the process in young adulthood.
DISH-like in young patients?
Retinoid arhtropathy related to retinoids intake for treating skin consition
Normal atalantoaxial interval
2-3mm
RA with atlantoaxial instability
what’s the complication?
Atlantoaxial impaction
with dens protruding into the foramen of Monro
GI manifestations of scleroderma
- esophagus - dilated
- small bowel - scarring, dilatation, and crowding of folds - “hidebound” small bowel
- large bowel - pseudosacculations
Pseudosacculations
seen in scleroderma
Kummel disease
Kummel disease is the eponym for avascular necrosis of the vertebral body after a vertebral compression fracture
Vertebral body contains air
DISH vs AS
- DISH
- large, flowing anterior osteophytes
- involves upper 1/3 (non-synovial) SI joints
- AS
- thin syndesmophytes
- involves lower 1/3 (synovial) SI joints
CPPD vs Hydroxyapatite deposition dz
- CPPD - calcium pyrophosphate dihydrate
- hydroxyapatite deposition disease - often calcium hydroxyapatite
Large subchondral cysts without other degenerative changes
Large subchondral cysts, without other destructive changes, are suggestive of pigmented villonodular synovitis.
The presence of an (hemorrhagic) effusion supports this diagnosis.
Synovial cyst
- most often involving the iliopsoas bursa, which may have normal connection with the hip joint capsule
- most common occurs in rheumatoid arthritis
- other findings include
- symmetric joint space narrowing
- osteopenia
- protrusio
Joint subluxations such as swan neck deformity
without osseous eorsions or peri-articular osteopenia
SLE
Severe ligamentous abnormality in the absence of erosive changes
Usually reducible
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Ankylosing spondylitis
- Ossification of the annulus fibrosis
- Reactive sclerosis at the site of osteitis in aneterior endplates –> shiny corners
- Reactive osteitis also leads to loss of normal concavity of the anterior vertebral body –> squaring of the anterior margin of the vertebral body
Note: normally, anterior margin of the vertebral body should be concave! Note the image below!
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Blount’s disease
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- osteochondrosis of the medial proximal tibial epiphysis, with result genu varus
- infantile type most common
- commonly in black patients
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Sites for degenerative changes in the SI joints
- subchondral sclerosis and osteophyte formation in one of two sites
- anteroinferior to the SI joint
- anterosuperior to the synovial portion of the joint (at the mid to upper 1/3 SI joint as seen on the AP film)
- may mimic osteoblastic metastasis, but can be seen nicely on axial CT
What to consider for a monoarticular arthritic process in an elderly man?
Gout