Week 3- Limb Radiography Flashcards
What is computed tomography?
- Better soft tissue differentiation than x-rays
- absence of superimposition
- Indications= bone lesions, bone erosions, fractures, Arthro-CT
What is Magnetic Resonance imaging?
- Much more improved soft tissue differentiation over x-ray and CT
- Indications= Ligaments, Menisci, Cartilage, Bone Marrow Imaging, Muscle Disease
What are the indications for ultrasonography?
- Swellings within or around the joint, long bone, tendon or muscle
- thickening of the tendon or tendon sheath
- Defect in the muscle or tendon
- Discharging the sinus tract
- Assessing vascularity with Doppler
What leads to a diffuse increase in tissue mass?
Subcutaneous fluid, oedema, lymphoedema, cellulitis, neoplasia,
emphysema
What leads to a localised increase in tissue mass?
Abscess, cyst, haematoma, neoplasia
* Assess adjoining bony structures for neoplasia
What leads to soft tissue atrophy?
Disuse, neurogenic, myositis, weight loss
What may cause an increased change in opacity?
- Artefacts
- Calcification
- Ossification
- Radiopaque foreign body
What may cause a decreased change in opacity?
- Fat
- Gas
- Facial Planes
What is reactive bone formation?
Increased thickness of normal trabeculae
What is neoplastic bone formation?
non-homogenous: osteosarcoma, chondrosarcoma
When would you consider there to be bone loss?
30-50% bone destruction before radiological lysis evident
What is osteopenia?
generalised decrease in bone radiopacity
* Imbalance between bone formation and resorption
What two things may cause osteopenia?
- Osteoporosis
- Osteomalacia
What is osteoporosis?
bone atrophy
* Less bone than normal but normal composition
What is osteomalacia?
reduction bone mass
* Failure of mineralisation of newly formed bone material
