Lecture 7- Ortho Flashcards
first line for bones?
Xray
when to use CT
- bone detail: extent and severity of fracture
- fracture fragment evaluation
when to use MRI?
- occult (hidden) fracture evaluation
- tumor eval
- soft tissue injuries (ligaments, meniscus, rotator cuff)
Describe use of bone scans
- involves IV injection of radioactive tracer that accumulates in bone that is undergoing rapid turnover/growth
- imaging of choice for detecting skeletal metastases
describe use of US in ortho
newer applications- include evaluating superficial structures (tendons), guiding injections, screening long bone fractures
Xray Views
comparison views
- esp use in kids
- compare R & L respectively
how to systematically read xray
- adequacy
- alignment
- bones (sometimes nutrient vessels look like fractures)
- cartilage (is there space where cartilage would be? can’t actually see cartilage)
- soft tissue
how to view xray
- look at each bone (smooth contours, lucencies/opacities)
- look at each joint
- look at soft tissue
what color usually are fracture lines?
lucent (black)
Shoulder
tips for shoulder view
- don’t forget to view clavicle (separate image)
- need to know view to read image
Shoulder
Grashey vs AP
- Grashey: glenohumeral joint, humeral tuberous
- AP: better for acromialclavicular joint, some parts of humerus
Humeral View
when/what views to order? what should be visible for good image?
- only order if concern for shaft fracture or tumor
- joint above & below
- always do IR & ER unless fracture or dislocation
Elbow Imaging
what is soft tissue issue
- pos fat pad sign (sail sign)
- dark area displacing the fat pad indicating blood/injury
Elbow Imaging
how to get proper AP view
lay arm as flat as possible
Elbow Imaging
purpose of the radiocapitellar line?
- helps us know if it is dislocated
Forearm Imaging
components
- just changing from pronation to supination does not give 2 proper views of radius/ulna
- make sure entire unit moves together
- bones should mostly overlap on lat view
- must include wrist + elbow
Wrist Imaging
components
- does not have to include fingers
- does not have to include radius/ulna shaft
- too much radius/ulna are sometimes signs of bad images
- scaphoid view ordered here
Hand Imaging
components
- “ok” sign for lat view
- finger tips should be visible
- oblique view to look at metacarpals
Hip Imaging
components
- AP, frog leg, pelvis most common
- cross table lateral possible not common
- MAKE SURE TO LOOK AT PUBIC RAMI
- bilat hip is different from pelvis
Femur Imaging
components
- AP should include knee and hip to be adequate
- difficult to accomplish lateral because of lead in groin and overlap of pelvis structures
- ok if not perfect, caution w reshooting
Knee Imaging
components
- several views possible, based on problem
- look at fibula & tibial tubercule
- should be WB unless fracture & pt can’t stand
Knee Imaging
when to use tunnel imaging?
ligament damage
Tib/Fib Imaging
Components
- often anlged on film because leg is too long
- must include knee/ankle joints
- only performed for fractures and tumors
Knee Imaging
which views should be wt bearing
Ap, Lat, oblique
Ankle Imaging
components
- AP + Lat: arthritis
- AP + Lat + Mortise: injuries
- mortise “straightens” things out
- don’t ignore post ankle
Fracture Terminology
Simple Closed fracure
2 fracture fragments, skin intact
may take 7-10d to be visible on xray
Fracture Terminology
compound (open) fracture
2 fracture fragments, skin is penetrated
Fracture Terminology
comminuted (complex) fracture
2+ bone fragments
Fracture Terminology
transverse
fracure like — across bone
Fracture Terminology
Spiral fracture
- “spiral” break in bone (curling)
- caused by rotational forces
- common in children (femur), aging females (humerus)
Fracture Terminology
oblique fracture
diagonal fracture ( / )
Fracture Terminology
angulation
- to describe direction of fracture
- dorsal, radial, ulnar, valgus, varus, lateral, medial
Fracture Terminology
displacement
- describe the DISTAL fragment when looking as displacement (proximal part of bone is the “anchor”)
- can be full displacement or side to side movement of the fragments
Fracture Terminology
Distraction vs Overriding
- distraction: fragments have been pulled apart
- overriding: overlap of fragments/shortening
Fracture Terminology
impaction
fragments have been driven together
Fracture Terminology
stress fracture
- opaque on imaging NOT lucent
- summation of microfractures caused by unusal or excess stress (athletes)
- tibia is common site of stress fx in all ages
Fracture Terminology
Pathologic Fractures
- fracture through bone abnormality (benign or malignant leading to bone weakness)
- minimal or no trauma
Fracture Terminology
Avulsion fracture
- fracture of bony fragment that is produced by the pull of a ligamentous or tendinous attachment
Fracture Terminology
describe avulsion fracture of the knee
- Segond fracture
- highly associated with ACL tear, get an MRI