226. MSK Imaging Flashcards
Pros/Cons of XRay
+: inexpensive, reproducible, minimal radiation, mainstay of bone alignment and density evaluation
-: miss occult fractures, limited soft tissue evaluation, 2D image of 3D structure
initial MSK test of choice
Pros/Cons of CT
+: superior spatial resolution, multi-planar imaging, widely available and fast
-: expensive, radiation, artifacts with metal
Fracture detail, occult fracture dx, pre-op planning
Pros/Cons MRI
+: superior contrast resolution, no radiation, multiplanar imaging
-: COST, not pt friendly (long, uncomfy, metal bad)
superior evaluation of joints, soft tissue, cartilage (and occult fracture)
Pros/Cons US
+: pt friendly, dynamic imaging, inexpensive
-: user dependent, limited evaluation of bone (low penetration depth)
Excellent for superficial soft tissue (tendon, ligament, nerve)
Bone Density Measurement (how, scoring, pros/cons)
Dual Xray Absorptiometry (DXA)
- low res imaging of lumbar spine/proximal femur
- T-score: difference b/w bone mineral density of pt and standard healthy young adult
- Z-score: matches by age and gender (more accurate to having lower average bone density)
pro: quick, available, cheap
con: overlying calcifications and compression fractures can skew scores
detects osteoporosis and fracture risk
Bone Scintigraphy (what is it, pros, cons)
sensitive but not specific, provides physiologic information
-: ionizing radiation (radioisotope deposits on high bone turnover sites - fractures, inflammation, infection, tumor), long time
+: whole body imaging, dx metastatic disease in bone
Fluoroscopy (what is it, pros, cons)
Most commonly used to guide joint injection
+: dynamic imaging - low res xray in real time
-: radiation to patient and operator
What is a myelogram
Dynamic imaging, evaluation of bone
Introduce contrast into thecal sac - visualize with fluoroscopy and CT
inferior to MRI for evaluating soft tissue
