Microsoft PowerPoint - TRUMA MSK WSInterventional Radiology-Body MRI
Umm Al Qura University
the continuity of bone or cartilage
General description
OPEN / CLOSED
1. greenstick
2. buckle / torus Fx=buckling of cortex due to compression
3. bowing Fx=plastic deformity of thin long bone (clavicle, ulna, fibula)
4. lead-pipe Fx=combination of greenstick + torus Fx
• Greenstick fracture
Transverse fracture
Special terminology
• Avulsion Fx=fragment pulled off by tendon / ligament from parent bone
• Transchondral Fx=cartilaginous surface involved
• Chondral Fx=cartilage alone involved
• Osteochondral Fx=cartilage + subjacent bone involved
• Description of anatomic positional changes:= change in position of distal fracture fragment in relation to proximal fracture fragment
• LENGTH = longitudinal change of fragments
– distraction = increase from original anatomic length
– shortening = decrease from original anatomic length
• impacted = fragments driven into each other
• overriding = also includes latitudinal change
Avulsion fractureAvulsion fracture
• ROTATION
fragments
• ANGULATION / TILT
• abnormal in 80% <24 hours, in 95% <72 hours
• Elderly patients show delayed appearance of positive scan
• broad area of increased tracer uptake (wider than fracture line)
– Subacute phase (2-3 months) = time of most intense tracer accumulation
• more focal increased tracer uptake corresponding to fracture line
– Chronic phase (1-2 years)
• slow decline in tracer accumulation
• in 65% normal after 1 year; >95% normal after 3 years
• MR (very sensitive modality; fat saturation technique most sensitive as it detects an increase in water content of medullary edema / hemorrhage)
• diminished marrow signal intensity on T1WI of fracture line
• low-intensity band contiguous with cortex on T2WI = fracture line of more advanced lesion
• MR:
• zone of low signal intensity on T1WI + variable intensity on T2WI (= discrete fracture line)
• surrounded by diffuse marrow edema (hypointense on T1WI + hyperintense)
• hyperintense components of circumferential periosteal reaction + early callus + surrounding edema adjacent to bone on T2WI with enhancement after IV Gd-chelate (DDx: osteomyelitis with more eccentric involvement)
• NUC (bone scan):
• increased abnormal uptake
increasing to 50% on follow-up):
• Follow-up radiography after 2-3 weeks of
conservative therapy
• NUC (the gold standard) almost 100% sensitive):
• abnormal uptake within 6-72 hours of injury (prior to radiographic abnormality)
• focal fusiform area of intense cortical uptake
• CT (least sensitive
Epiphyseal Plate Injury
• Prevalence:6–18–30% of bone injuries in children <16 years of
• Prognosis is worse in lower extremities (ankle + knee) irrespective of Salter-Harris type!
• mnemonic: SALTR
• Above physis=type 2
• Through physis=type 4
• Rammed physis=type 5
• road traffic accidents and falls from
heights
largest category
posterior vertebral (P) and
trauma:
posterior ligamentous disruption
FlexionTeardrop fracture
Fracture through the antero-inferior aspect of the vertebral body, often with anterior displacement of the fragment.
Commonly associated with ligamentous disruption and the fracture is unstable.
This differs from an extension teardrop fracture in that the anterior height of the vertebral body is usually reduced, in keeping with the mechanism of injury
Teardrop fracture
trauma or ligamentous avulsion
C1-C2 Dislocation
Odontoid fracture
• Type 1 occurs at the tip and is stable.
• Type 2 involves the junction of odontoid and vertebral body.
• Type 3 occurs through the superior aspect of C2 at the base of the odontoid.
Types 2 and 3 are unstable especially if associated with anterior or lateral displacement.
Odontoid fracture
highly unstable.
The vertebral body above displaces
anteriorly by at least 50% of the AP
diameter of the vertebral body.
The facets often appear ‘locked’.
Bilateral locked facets
Hangman’s fracture
Hangman’s fracture
• Hangman’s fracture:
Bilateral fracture through the pedicles of C2 with some degree of subluxation of C2 on C3 . Common in road traffic accidents .
This is an unstable injury.
Vertical compression injuries
• Burst fracture: Intervertebral disc is driven into the vertebral body
below.Fracture fragments may impinge on the cord
and thus should be thought of as unstable even
though the fracture itself is stable
Jefferson fracture
C1 laterally leading to fractures of the
anterior and posterior arches with
associated transverse ligament rupture
vertebral body below.
and thus should be thought of as unstable
even though the fracture itself is stable
Burst fracture
Chance Fracture
Chance Fracture
• Originally most often caused by seat belts as hyperflexion injuries in automobile accidents
• With lap belts, it is now seen more often with falls
• Chance fractures are hyperflexion injuries in which there is distraction of the posterior elements and impaction of the anterior components of the spine
• Instability is common
• Mechanism: forced abduction of thumb
• small fragment of 1st metacarpal continues to articulate with trapezium
• lateral retraction of 1st metacarpal shaft by abductor pollicis longus
• Rx: anatomic reduction important, difficult to keep in anatomic alignment
• Cx:pseudarthrosis
metacarpal
• = SKIER'S THUMB (originally described as chronic lesion in hunters strangling rabbits)
• Mechanism: violent abduction of thumb with injury to ulnar collateral ligament (UCL) in 1st MCP (faulty handling of ski pole)
• disruption of ulnar collateral ligament of 1st MCP joint, usually occurring distally near insertion on proximal phalanx
• radial stress examination necessary to document ligamentous disruption]
Gamekeeper's Thumb
Perilunate Dislocation
• Occurs when the lunate maintains normal position with respect to the distal radius while all other carpal bones are dislocated posteriorly
• 2 to 3 times more common than lunate dislocation
• most commonly dorsal dislocation
• Relatively rare
• Very commonly associated with a scaphoid waist fracture – Sometimes ulnar styloid fracture
– Lunate appears triangular in shape on frontal view
• Lunate rotates forward slightly on lateral view
• In lateral view, all other carpal bones are dislocated posterior with respect to lunate
Perilunate Dislocation
Lunate Dislocation
• Most commonly associated with a trans-scaphoid fracture
• Involves all the intercarpal joints and disruption of most of the major carpal ligaments
• Produces volar dislocation and forward rotation of lunate – Concave distal surface of lunate comes to face anteriorly
• Capitate drops into space vacated by lunate
• Capitate and all other carpal bones lie posterior to lunate on lateral radiograph
• Triangular appearance of lunate on frontal projection
Lunate Dislocation
SCAPHOID FRACTURE
fractures!
hand
weeks after treatment with short-arm spica cast!
• MR: high sensitivity
SCAPHOID FRACTURE
• Prognosis dependent on : – fracture displacement = >1 mm offset / angulation / rotation of fragments (less favorable)
– location (blood supply derived from distal part): • distal 1/3 (10%) = usually fragments reunite
• middle 1/3 (70%) = failure to reunite in 30%
• proximal 1/3 (20%) = failure to reunite in 90%
– Good prognosis with distal fracture + no displacement + no ligamentous injury!
– Less favorable prognosis with displaced / comminuted fracture + proximal pole fracture!
• Cx: avascular necrosis of proximal fragment
Scaphoid Fracture
Scaphoid Fracture
Kienbock's disease
• Location:uni- > bilateral (usually right hand)
• initially normal radiograph
• increased density + altered shape + collapse of lunate
• Cx: scapholunate separation,
Boxer's Fracture (Metacarpal Neck)
• transverse fracture of distal metacarpal
(usually 5th)
• nonarticular radial fracture in distal 2 cm
• dorsal displacement of distal fragment +
volar angulation of fracture apex
• ± ulnar styloid fracture
Anterior Shoulder Dislocation
Posterior Shoulder Dislocation