metabolic bone disease: Radiology Flashcards
What are the main imaging methods we can use to look at bones?
Xrays, CT, bone densiometry-all measure density
MRI-biochemical composition
Radionuclotide bone scans-bone turnover
What is osteoporosis?
Decrease quantity of bone mass
Quality and microstructure is FINE-just have less of it
What imagine do you use to diagnose osteoporosis?
Bone densiometry-DEXA
Measure bone mineral density
Gives a t scole or Z score (reference age and sex)
if T under 2.5 -measured as 2SD away from peak density
T score does vary between the measure bones (like which vertebrae)
Main reason to do is to measure/asses fracture risk - (can use fracture risk assessement tool (on google)
What are the radiological signs of osteoporosis?
Loss of cortical bone/thinning of cortex-bones look darker on Xray
Loss of trabeculae
Insufficiency fractures (stress fractures due to NORMAL stress on abnormal bones (coccyx, femur, others) –cant see them on Xray/CT before callus formation-see white at attempts of healing
MRI-can see bone oedema (low T1 signal and high T2)
bone scan-areas of increased uptake (Honda site at pelvis (black H))
What is osteomalacia? What art the main signs
Decrease bone mineralisation-soft bone (osteopenics)
Soft bone, osteopenia (abnrmal mineralisation-darker bone, Loosers Zones
In adults-Osteomalacia-Loosers zones, coldfish vertenraed, bending deformities
Rickets in children-signs mainly on grwoth plates-widened growth plates without calcifications-bends under weigh and tries to counteract by bending
Fraying of metaphysis-
What are loosers zones? and Coldfish vertebraer?
Inssufiency fractures at high tensile stress
Femus, lateral scapula, pubic rami,
Looks like white lines in a bone-sclerosis
tends to be in marginal locatons and 90 degree from bone
Coldfish vertebrae-dips at each endplates-biconcave deformities at vertebeae
What is hyperparathyroidism
Primary-Parathyroid adenoma
Secondary-CKD/rickets/osteomalacia
Tertiary-autonomous PTH production
Overall-increase resorption Sub periosteal, subchondral, intracortical, brown tumours
How does hyperparathyroidism looks on imaging?
Frayed edges of bones-sub periosteal resorbption
Salt and pepper skull-brown tumour-looks like dark holes in the bone-looks like a tumor (can also be in other bones)
What is renal osteodystrophy? What are the imaging signs?
Collection of bone disorders caused by CKD-osteoporosis and osteomalacia
Secondary Hyperparathyroidism-
combine all the signs
Cuttlefish vertebear, brown tumours, osteoprorosis
But also Sclerosis-in vertebrae-end plates have sclerosis-dense white outside and inside very dark osteomalacia
Also high serum Ca cause soft tissue calcification-vessels, cartilage (like in knee-should have dark gap bewteen bones–can look very white/unified once calcified)
What is pagets disease?
Disease of bone remodelling
3 phases-lytic phase, mixed phase and sclerotic phase
keeps to one bone-does not jump bone
Cause bone pain, deformity, spontanous fracture
Raised serum Alk phos, urinary hydroxyapaptite
How does pagets disease look on imagine
usually catch it in sclerotic phase
Cortical thickening, bone expansion, coarsening of trabeculae, osteoporosis circumscripta
Bone-looks whiter-cortex thicker-part of sclerotic phase
Trabecular looks Coarse
Bones tend to look bigger than expected
Can cause bend in bone-but usually stuck to one
