5. Musculoskeletal Imaging Flashcards
What is the most used imaging for skeletal diagnostics?
X-ray, plain radiographs
MSK MRI - T1 weighted images are good for?
Not fluid sensitive, good for anatomy. Fat will be bright, fluid will be dark. GOod for bone marrow infiltration
What does PD stand for?
Proton density
When can we call it an infiltrative process?
When it is the same density or less than the adjacent muscle
What structures are always hypointense / dark on all sequences? (Unless pathological)
- Tendons
- Ligaments
- Fibrocartilage (meniscus, articular disk)
What are the structure densities on PD (aka T2)
- Fluid is bright due to high water content
- Fat is bright unless you use fat suppression (that includes bone marrow)
- Meniscus, tendon, ligament… are dark
What is PD / T2 useful for?
IT is useful to detect pathologies, because they will have more fluid than normal tissue - so it will look brighter / highlighted on the imaging.
What differs in PD / T2 when the fluid is not pure (aka serous, fatty)?
It becomes darker, less bright - we can tell from the MRI that the fluid has a different quality.
What are the signs of fracture on X-ray?
- Lucent fracture line
- Macrotrabecular fracture : dense sclerotic line because the trabeculae are compressed together
What is MRI good for in trauma imaging?
- Stress fracture
- occult fractures (not visible on XRAY but high suspicion of injury)
What is a stress fracture?
Fracture caused by an abnormal load on a normal bone
What is US good for in trauma?
- Superficial soft tissue injuries
- Evaluation of joint fluid
What is the unhappy triad of the knee?
- ACL
- MCL
- Medial meniscus
What do we use to visualize superficial ligaments and tendons?
Ultrasound imaging
What do we use in cervicospinal trauma visualization?
CT, which can be confirmed with an MRI after
