RADIOLOGY Flashcards
INDICATIONS FOR XRAYS IN ORTHO
⦁ hx of blunt trauma
⦁ deformity of bone or joint following injury
⦁ hx of pain, swelling, or loss of motion of a joint, have a sense of instability
⦁ infection
⦁ foreign body
⦁ night pain
MRI
MRI = provides good contrast between the different soft tissues of body; easy to evaluate fluid within muscle or tendon to tell if torn or not. especially useful in imaging brain, muscles, heart, and cancer
BRAIN, MUSCLES, HEART, CANCER
- very rarely get MRI to evaluate bone; more for soft tissues (ligament, tendon, muscle injury)
- most bones evaluated with xray or CT
indications for MRI
⦁ evaluate soft tissue injury as opposed to bony injury. Ex: ligament, tendon, muscle injury
⦁ better evaluate soft tissue mass
⦁ r/o fluid collection in the body
⦁ define abnormalities within bone seen on xray
⦁ r/o stress fracture or infection
⦁ evaluate spinal injury
MRI TO EVALUATE SOFT TISSUE INJURIES
- Knee: ACL / MCL / PCL / LCL / meniscus, loose body
- Shoulder: rotator cuff, biceps tendon, labrum
- Elbow: UCL/RCL, extensor/flexor tendons for epicondylitis, biceps tendon rupture, loose body
- Wrist: Extensor carpi ulnaris injury, TFCC tear
- Ankle & Foot anterior tibial tendon injury, peroneal, tibial tendon, achilles tendon partial tear
- Hip - Labral tear
Labral tear = one of the biggest reason to get MRI (inject contrast dye to evaluate labrum)
ASPIRATED FLUID FROM KNEE AND WHAT IT MEANS
⦁ bright red blood aspirated = ACL
⦁ dark red blood aspirated = venous blood = patellar dislocation
⦁ if blood / fat = tibial fracture
MRI FOR SOFT TISSUE MASSES
⦁ lipoma
⦁ hematoma
⦁ osteosarcoma
⦁ ganglion cyst
wouldn’t really get an MRI for ganglion cyst location on dorsal ganglion; but if ganglion cyst located elsewhere, may not be as sure…
MRI FOR FLUID COLLECTION IN BODY
⦁ Effusion of a joint - shoulder, hip
⦁ no need to MRI, olecrenon bursitis, patellar bursitis
⦁ infection of fluid collection within soft tissue compartments
⦁ baker’s cyst in the knee
MRI TO FURTHER EVALUATE BONE ABNORMALITIES FOUND ON XRAY
⦁ Stress fracture: tibia, metatarsals, tibial plateau, femoral neck ⦁ lytic or blastic lesions seen on xray ⦁ bone contusion ⦁ r/o occult fracture, scaphoid fracture ⦁ AVN ⦁ osteomyelitis
Also used for spine pathology
seen better on MRI compared to xray
stress fractures (ex: tibia)
scaphoid fractures
AVN
risk factors for AVN
alcohol use
chronic steroid use
MRI FOR SPINAL PATHOLOGY
⦁ Herniated disc ⦁ bulged disc ⦁ spinal stenosis ⦁ compression fracture (acute vs chronic) ⦁ neoplasm ⦁ pars defect
indications for CT
⦁ Cervical injury - can’t see on xray well due to overlapping shadows. can better rule out cervical fracture after trauma with CT
⦁ To better define comminuted fractures (acetabular fractures, calcaenous fractures, articular fractures)
⦁ evaluating joints for preop eval for surgery
⦁ CT Myelogram of spin = for ppl who can’t undergo MRI (pacemark/other metal objects). Myelogram = CT with dye injected into dura
Indications for CT Myelogram
patients who have had previous spinal surgery, or patients who don’t qualify for MRI (pacemaker/other metal objects) - -inject dye into dura
indications for CT over xray
- cervical injury - ex: odontoid fracture
- tibial plateau fracture
- talus fracture
- calcaneal fracture
- bony bankart
BONE SCAN
- can be full body or localized to a body part
- will show bone turn over and osteoblastic acttivity, but will NOT show osteoclastic activity
- bone scans = best used for mets disease - such as prostate cancer
- not good for lytic lesions (clastic activity) - such as Multiply Myeloma
- other reasons for scans = stress fracture (MRI), infection (MRI), or occult (hidden) fractures
bone scans = not good for
multiply myeloma
lytic lesions
- clastic activity
tibial stress fracture
bone scan or MRI
one place bone scans are definitely used for =
tibial stress fracture
and mets
PLAIN XRAYS IN ORTHO - KNOW HOW TO DESCRIBE FRACTURE
⦁ Displacement ⦁ angulation ⦁ impaction ⦁ intra-articular ⦁ comminuted ⦁ spiral ⦁ greenstick ⦁ buckle ⦁ transverse vs oblique
- be wary of intra-articular fractures
- get AT LEAST 2 xray views 90 degrees to each other
- re-xray in about 1 week
view of xray good for evaluating glenohumeral joint
axillary view
also true AP
shoulder Y view = good for dislocations / fractures
xray of hand
get AP, oblique, and lateral
most commonly fractured bone in children & adolescents
CLAVICLE
M > F
80% are in the middle 1/3 of clavicle (mid shaft)
15% are distal 1/3
5% are proximal 1/3 (uncommon) - more worrisome
Y view is an xray view of the
shoulder
mortis is an xray view of the
ankle
