Acute Radiology Flashcards
Fracture Terminology
- Open/Closed
• Open/Closed : Communication with skin
Fracture Terminology
- Simple/Comm
• Simple/Comm. : Fragments 2 or more
Fracture Terminology
- Complete vs Incomplete
• Complete/Incomplete: all cortex disrupted
Fracture Terminology: Displacement
Apposition and alignment defined in relation to
distal fragments:
Displacement (e.g., medial lateral, posterior,
anterior)
Fracture Terminology:
Angulation
Apposition and alignment defined in relation to
distal fragments:
Angulation (e.g., medial, lateral, posterior,
anterior)
Fracture Terminology:
Overriding
Apposition and alignment defined in relation to
distal fragments: overlap of fragments
Fracture Terminology:
Distracted
Apposition and alignment defined in relation to
distal fragments: separated fragments
Fracture Terminology: Green Stick Fracture
Break of one cortical margin
Only with intact periosteum due to tension on soft growing bone
Fracture Terminology: Torus Fracture
Buckling of cortex due to compression
Fracture Terminology: Pathologic Fracture
Fracture at site of preexisting osseous abnormality
Cause: tumor,osteoporosis, infection,metabolic disorder
Fracture Terminology: (Fatigue) Stress Fracture
Fractures produced as a result of repetitive prolonged muscular action on a bone that has not accommodated itself to such actions, activity-related pain abating with rest
(Fatigue) Stress Fracture Features on XR
X-Ray:
• 15% sensitive in early fractures, increasing to 50% on follow-up)
• Subtle blurring of trabecula margins
• Sclerotic band (due to trabecular compression usually perpendicular cortex)
Fracture Terminology: Salter Harris
Epiphyseal plate Injury
Types: I) S: Slipped II) A: Above III) L: Lower IV) T: Through V) R: Rimmed
Salter Harris Types:
Slip through physis+ extending
through metaphysis separating a triangular fragment (“corner sign”)
Type II: 75% (most common)
• Location: distal radius (33-50%), distal tibia, fibula, phalanges
• Prognosis: good, may result in minimal shortening
Salter Harris Types:
Line of fracture: vertically/ obliquely through epiphysis to periphery of physis
Type III: 8%
• Intra-articular fracture
• Location: distal tibia,distal phalanx.
• Types III & IV are more prone to chronic disability
Salter Harris Types:
Fracture involves metaphysis+
physis+ epiphysis
Type IV: 10%
• Prognosis: guarded (may result in deformity)
• Types III & IV are more prone to chronic disability
Salter Harris Types:
Crushing injury often associated with: fracture
of adjacent shaft
Type V: 1% • Crushing injury with injury to vascular supply • Location: distal femur, proximal tibia • No intermediate radiographic finding • Type V associated with growth disturbances and has a poor functional prognosis
Fracture Terminology: Bennett Fracture
Mechanism: forced abduction of thumb
• Intra-articular fracture dislocation of base of 1st
metacarpal
• A small fragment of 1st metacarpal continues to articulate with trapezium
Fracture Terminology: Boxer’s Fracture
Fracture of the MCP neck (most commonlv 5th MCP)
with volar angulation and often external rotation of the distal fragment
Fractures: Most common carpal fracture
Scaphoid Fracture
Most common fracture of carpus (90%)
Mechanism: Fall on outstretched hand in young adults.
Locations:
Waist 70%
Proximal pole 20%
Distal pole, 10%
Fracture Terminology: Mallet Finger
Baseball (mallet) finger
• Dorsal Avulsion of extensor mechanism
• DIP flexion with or without avulsion fragment
Fracture Terminology: Barton’s Fracture
- Intra-articular fracture of the volar or dorsal margin of the distal radius.
- The carpus usually follows the distal fragment.
- Unstable fracture requiring open reduction and internal fixation and/or external fixation.
Fracture Terminology: Chauffer Fracture
Triangular fracture of radial styloid process.
Fracture Terminology: Colle’s Fracture
- Extra-articular fracture (in contradistinction to Barton’s fracture)
- Distal radius is dorsally displaced/angulated
- Ulnar styloid fracture 50%
- Foreshortening of radius
Complications of Colle’s Fracture
Median, ulnar nerve injury, OA
Fracture Terminology: Galeazzi Fracture
Fracture of ulnar shaft+ dislocation of radial
head
• Radial shaft fracture (most commonly) at junction of distal to middle third with dorsal angulation
• Dislocation of distal radio-ulnar joint
• Ulnar plus variance ( radial shortening) implies complete
disruption of interosseous membrane (instability of radio-ulnar joint)
Fracture Terminology: Monteggia Fracture
Mechanism: direct blow to the forearm
Anteriorly angulated proximal ulnar fracture with Anterior dislocation of radial head
Reverse Monteggia: Radial head displaced posteriorly, Dorsally angulated proximal ulnar fracture
Fracture Terminology: Fat Pad Sign
• Displacement of anterior fat pad indicative of elbow fracture
• Posterior fat pad
Indicating elbow joint effusion with (supracondylar/lateral condylar /
proximal ulnar or radial fractures)
Fracture Terminology: Elbow Lines
Alignment:
A) Radio-Capitellar Line
B) Anterior Humeral Line.
Treatment Radial Head Fracture
- No displacement: splint, cast
- More than 3 mm displacement on lateral view: open reduction and internal fixation
- Comminuted: exicision of radial head
Radiographic Features of Radial Head Fracture
- Positive fat pad sign
- Fracture line may be difficult to see on
- standard projections.
Radiographic Features of Humeral Head Fracture
• Fracture lines according to Neer classification
• Pseudosubluxation: inferior displacement of
humeral head due to hemarthrosis
Site of clavicle fractures
- Lateral third: 15%
- Middle third: 80%
- Medial third: 5%
Dislocation vs subluxation
Dislocation: separation of articular surface of glenoid fossa and humeral head that will not reduce spontaneously.
Subluxation: transient incomplete separation that reduces spontaneously
Shoulder Dislocation is divided into two large categories:
- TUBS (Traumatic unidirectional Bankart requires surgery)
* AMBRI ( A traumatic multidirectional bilateral recurrent instability)
Anterior Shoulder Dislocation: Radiographic findings
• Humeral head lies inferior and medial to glenoid
Two lesions can occur as humeral head
strikes the glenoid:
• Hill-Sachs lesion (posterior-superior and lateral) of humeral head, (best seen on Ap view with internal rotation)
• Bankart lesion (antero-inferior) of glenoid (may require CT)
Posterior Shoulder Dislocation: Radiographic findings
- Humeral head lies superior to glenoid
- Trough sign: compression fracture of the anterior humeral surface
- Posterior displacement is best seen on the axillary view.
- Light bulb sign: a circular appearance of the humeral head, arm fixed in internal rotation.
- Rim sign (66%) = distance between medial border of humeral head+anterior glenoid rim >6 mm
General indicators of cervical spine fracture instability
- more than one vertebral column involvement
- increased or reduced intervertebral disc space height
- increased interspinous distance
- facet joint widening
- vertebral compression greater than 25%
cervical spine fractures: 4 major mechanisms
- Flexion
- Extension
- Rotational and shearing, each associated with certain fracture patterns
