Metabolic Bone Disease: Radiology Flashcards
What imaging looks at bone density? (3)
Xrays, CT and bone densitometry all look at density
What imaging looks at bone biochemical composition?
MRI
What imaging looks at bone turnover?
turnover (osteoblastic activity of bones) Radionuclide bone scans
What is a RADIOLOGICAL SIGN
A change in imaging appearance, whether structural or functional, that may point towards a pathology
How do you diagnose osteoporosis? Score for positive diagnosis?
bone densitometry (e.g. dual energy absorptiometry (DEXA)) T- score 2.5SD below mean of a healthy young person
Radiological signs that may indicate osteoporosis? (3)
- Loss of cortical bone/thinning of cortex
- Loss of trabeculae
- Insufficiency fractures
What is an insufficiency fracture?
Stress fractures due to normal stress on abnormal bones
Common sites of insufficiency fractures?
- Sacrum
- Underside of femoral neck
- Vertebral bodies
- Pubic rami
Types of imaging for insufficiency fractures and their results?
XR/CT: - Initially normal - Can get periosteal reaction and callus - More commonly increased sclerosis around fracture lines MRI: - Bone oedema BONE SCAN: - Increased osteoblastic activity as bones attempt to heal
Bones With decreased bone mineral is named what?
- Osteopaenic bone
- Soft bone
Bones With Too much un-mineralised osteoid:
- Looser’s zone
OSTEOMALACIA can result in what (if Ca remains low)
May result in 2ndary HPT if calcium remains low
Radiological signs of osteomalacia? (5)
- Mature skeleton
- Osteopaenia
- Looser’s zones
- Codfish vertebrae
- Bending deformities
When does rickets occur?
Osteomalacia before growth plate closure
LOOSER’S ZONES common sites? Why do these occur here? (5)
Pseudofractures at high tensile stress areas
- Medial proximal femur
- Lateral scapula
- Pubic rami
- Posterior proximal ulna
- Ribs
Describe a Looser zone on a radiological scan
Typically, short lucent lines with irregular sclerotic margins
Describe CODFISH VERTEBRAE? what are they seen in?
Biconcave deformity of vertebrae
Seen in:
- Osteomalacia
- Osteoporosis
radiological scan of rickets?
- Indistinct/frayed metaphyseal margin
- Widened growth plate with calcification
- Cupping/splaying metaphyses due to weight bearing
- Enlargement of anterior ribs
- Osteopaenia
Main areas of bone resorption? (4)
- Subperiosteal
- Subchondral
- Intracortical
- Brown tumours
What does type of radiology in osteomalacia depend on?
Age and closure of growth plates
Bone density and PTH levels/resorption in 2ndary HPT?
shows bone resorption and increased density
renal osteodystrophy has Features of what other diseases?
- Osteomalacia
- Osteoporosis
- 2o Hyperparathyroidism
What is seen in renal osteodystrophy in radiological scans? (4)
- Subperiosteal
- Subchondral
- Intracortical
- Brown tumours
^ lesions
Sclerosis- vertebral endplates giving a rugger jersey spine- increased density at endplates and reduced density in middle of vertebrae
Soft tissue calcification (vessels, cartilages)
What is seen in radiology of Pagets? (5)
- Cortical thickening
- Bone expansion
- Coarsening of trabeculae
- Osteolytic, osteosclerotic and mixed lesions
- Osteoporosis circumscripta (holes in the bones
