Skeletal Radiology Flashcards
X ray indications
what is it not good for
Indications
- fractures
- radioopaque (metal) FB
- lung pahology
- intestinal obstruction
Not Good For
- evaluation of soft tissues
- differentiate between benign and cancerous lesions
- abdominal pain (CT is better here)
- blunt trauma to organs
- evaluate smooth muscle/organs
- neck/head/face trauam
MRi
Indications- what is it good for
- meniscal, ligament and tendon injuries
- bone contusions
- occult or stress fractures
- infection
- malignancy
- spine disorders…
- disc disease
- cancers
- acutiy of findings on spine imaging
Preferred imaging for
- head, neck and facial trauma
- suspected fracture with negative plain films
- osteomyelitits
- contusion of bone
- bone tumor
Head, Neck and Facial Trauma = CT No Contrast
Suspected fracture but plain films = CT NO Contrast
Osteomyelitis = MRI WITH CONTRAST
Bone Contusion = MRI NO Contrast
Bone Tumor = MRI WITH Contrast
Nuclear Bone Scan
- how it works
- Indications
How it Works
- a radioactive tracer is injected which is highly sensitive to areas of high bone turnover: these will “light up” on the gamma ray imaing (x-ray)
- helps determine where the normal pattern of exretion and uptake is within the bones: gives functional and physiologic information about the bones
Indications
- metastatic disease
- tumors
- trauma
- Infection
- Metabolic d/o
- infarction
- bone density
- bone marrow distrubution
How do you determine a new v old fracture on xray
- characteristics of each
Acute Fracture
- aburpt disruption of the bone, where normal contour is altered
- fracture lines will be black and linear: SHARP angles and lines where they change course direction/jagged edges
Healed/Old Fractures
- well corticated, with smoother edges
- may still see darker areas, but the edges are smooth
Difference between a Sesamoid Bone and Accessory Ossicles
Sesamoid Bones
- normally in majority of individauls: bones which are totally or partly embedded in the tendon
- help to stabilize and absorb the force of movement
- think baout the seasmoid bone in the big toe
Accessory Ossicle
- additional bones/parts of bone which are not normally there
-
Fracture “Reporting”
- terminology
- Fragments
- Line Direction
- Orientation of Fragment
- shortening of fracture
- avulsion
Fragment: number of fragments of bone
- simple : two pieces
- comminuted: multiple pieces “shattered”
Line Direction: what way is the fracture going
- transverse: horizontal
- oblique: angle
- spiral: around the bone
Fragment Orientation
- Displacement: the amount of movement of the DISTAL fragment offset
- Angulation: describes the angle between the distal and proximal fragments (is it ulnarlly, radially deviated) or is it dorsal (pushed back) compared to volar anterior/palmar displacement)
- Rotation: displacement with rotation of the dital fragment
always described in terms of the distal fragment
Avulsion Fracture: a small piece of bone pulled away from the edge of a bone: usually due to a tendon being pulled
Shortening: how much overlap of the segments there is
- when shortened, but displaced you can see amount of shortening
- when its compacted, not displaced but just compacted into each otehr
Compound Fracture: an open fracture
Salter Harris Pediatric Bone Fracture Scae
I- V type
Type I: a fracture through the growth plate transveresely (essentially: you cant see it on xray)
Type II: a fracutre through the growth plate AND the metaphysis (the larger portion) or area which is most commonly above the growth plate
Type III: a fracture through the growth plate AND through the epiphysis (the distal protion in compared to growth plate)
Type IV: a fracture through the growth plate, the metaphysis and the epiphysis (all three!)
Type V: Erasure (compression) of the growth plate: smushing the two together
rule of thumb: the large piece is the metaphysis,the smaller piece is the epiphysis
Separation
Above
L below
T through both
ER erasure (compression of plate)
Colles Fracture
Smith Fracture
Colles Fracture
bent fork appearance
- a fracutre at the distal radius which allows for dorsal angulation of the distal fragment
Smith Fracture (the opposite!)
- a distal radius fracture which results in palmar angulation of the dital fragment
Boxers Fracture
Scaphoid Fracture
Boxers Fracture
fracture at the base of the 5th metacarpal: resulting in palmar angulation: think the knuckle from a punch thrown
Scaphoid Fracture: pain in the anatomical snuff box as a result of a scaphoid fracture
- scapohid bone sits on the radial side of the write
Radial Head Fracture
v
Supercondylar Fracture of the distal humerus
Signs on Xray
- see a posteriod elbow fat pad: which is not normal and usually a result of inflammation within the elbo joint as a result of the fracture
- the anteroi fat pad: is normally present; can have a “sailboat” shape when the radial head is fractured
Supercondylar Fracture of the Distal Humerus
- common in kids: a fracture in the eblow: at the level just above the condlyes
- can be commonly missed
Shoulder Dislocations
Anterior V Posterior
Anterior: most common
- pt. will hold shoulder abducted with slight external rotation
- shoulder looks square and not round
Posterior: less common
- pt will hold shoulder adducted and internally rotate
- on xary: lack of half moon overlap which is normally seen on the AP view
- on xary: lack of joint space: trough sign
- light bulb sign: see then entire head of the humerus
a dislocation: the two articular surfaces which normally are in conteact with each other are not
need to get a Y view on the xray to see the displacement
Femoral Neck Fracture
- when the femoral neck is fractured: there is a shortening of the leg as a result of the fracture: and an inabiilty to internally rotate: leaving hip in external rotation
Tibial Platueau Fracture
- complaint of knee pain: but becuase it is at the level of the articulation and joint space, pt will not be weight bearing
- commonly from a high energy loading force : a valgus stress will fracture the lateral plateau, a varus stress will fracture the medial
Tibial Platueau Fracture
- complaint of knee pain: but becuase it is at the level of the articulation and joint space, pt will not be weight bearing
- commonly from a high energy loading force : a valgus stress will fracture the lateral plateau, a varus stress will fracture the medial
