Unifacet dislocation MRI

Presented by:
Dr Paul Licina — Spine Surgeon

Event:
Bone School Presentation - 2014

1. Unilateral cervical facet fracture/dislocation
Treatment options
James Schuster (USA)
Paul Licina (Australia)
Davos Masters Course
December 2010

4. Scenario 1

•55 year old otherwise healthy woman
•fell down the stairs earlier in the day
•brought to University Hospital – dedicated spine service
•complaining of neck and right arm pain
•right 4/5 biceps and 4/5 triceps weakness (ASIA D)
•CT shows right unifacet dislocation
•no other injuries

5. Scenario 1

•immediate closed reduction?
•MRI first?
•straight to OT for open reduction?
•MUA?

•anterior surgery?
•posterior surgery?

6. Scenario 2

•55 year old otherwise healthy woman
•fell down the stairs one week ago
•brought to University Hospital – dedicated spine service
•complaining of neck and right arm pain
•right 4/5 biceps and 4/5 triceps weakness (ASIA D)
•CT shows right unifacet dislocation
•no other injuries

7. Scenario 3

•55 year old otherwise healthy woman
•fell down the stairs earlier in the day
•brought to University Hospital – dedicated spine service
•complaining of neck and right arm pain
•complete motor loss with sacral sparing (ASIA B)
•CT shows right unifacet dislocation
•no other injuries

8. Scenario 4

•55 year old otherwise healthy woman
•fell down the stairs earlier in the day
•brought to district hospital – MRI 30 miles away
•complaining of neck and right arm pain
•right 4/5 biceps and 4/5 triceps weakness (ASIA D)
•CT shows right unifacet dislocation
•no other injuries

9. MRI
surgery
reduction
DECISIONS

10. Treatment options
•Treatment opinions
•25 members of Spine Trauma Study Group surveyed
•Presented with ten clinical vignettes with radiographs and CT
•Asked whether would obtain MRI before reduction
•Very poor agreement
•Then presented with MRI and asked whether would perform closed
or open reduction
•Still very poor agreement

The Timing and Influence of MRI on the Management of Patients
with Cervical Facet Dislocations Remains Highly Variable
Grauer et al J SPINAL DISORD TECH 2009

11. Reduction or MRI
•Facts
•Aim of treatment is to stabilise and decompress
•Aims can be achieved by reduction

•Unreduced dislocation has risk of further neurological injury
•Reduction can lead to neurological deterioration
•Incidence of both is low but occurrence is catastrophic

12. Reduction or MRI
•Questions for the literature
•Does early decompression improve the outcome?
•Tells us whether delay for MRI is relevant

•Does neurological deterioration occur with closed reduction?
•Tells us whether closed reduction safe

•Does disc herniation predispose to neurological deterioration?
•Tells us whether need to identify herniation before reduction

•Does MRI predict outcome or guide treatment?
•Tells us whether MRI is of value

13. Reduction or MRI
•Does early decompression improve the outcome?
•Animal studies have shown that neurological recovery inversely
related to duration of cord compression
•Recent metanalyses suggest that early decompression can
improve clinical outcome

Timing of Decompressive Surgery of Spinal Cord after Traumatic Spinal Cord
Injury – An Evidence-Based Examination of Preclinical and Clinical Studies
Furlan et al J NEUROTRAUMA 2010
The Influence of Spinal Canal Narrowing and Timing of Decompression
On Neurological Recovery After Spinal Cord Contusion in a Rat Model
Dimar et al SPINE 1999

14. Reduction or MRI
•Does neurological deterioration occur with closed reduction?
•Metanalysis of clinical reviews of closed reduction
•More than 1200 patients
•80% success rate of reduction
•<1% permanent neurological deterioration
•Detail insufficient to determine nature or cause
•4% transient neurological deterioration
•Only two awake patients deteriorated with closed reduction but
after a delay of hours or days

Initial Closed Reduction of Cervical Spine Fracture-Dislocation Injuries
Supplement NEUROSURGERY 2002
Risk of Early Closed Reduction in Cervical Spine Subluxation Injuries
Grant et al J NEUIROSURG (SPINE) 1999

15. Reduction or MRI
•Does disc herniation predispose to neurological deterioration?
•Reports of neurological deterioration in closed reduction followed
by open reduction if unsuccessful
•Herniated disc found in patients with neurological deficits
•No relationship found between pre-reduction herniated disc and
neurological deterioration

Extrusion of an Intervertebral Disc Associated with Traumatic Subluxation
or Dislocation of Cervical Facets
Eismont et al J BONE JOINT SURG AM 1991
Neurological Deterioration After Reduction of Cervical Subluxation –
Mechanical Compression by Disc Tissue
Robertson and Ryan J BONE JOINT SURG BR 1992
Magnetic Resonance Evaluation of the Intervertebral Disc, Spinal Ligaments
and Spinal Cord Before and After Closed Traction-Reduction
Vaccaro et al SPINE 1999

16. Reduction or MRI
•Does MRI predict outcome or guide treatment?
•Issues of availability, delay and transfers
•MRI not shown to predict neurological deterioration
•MRI can be difficult to interpret in presence of subluxation
•Variable interpretations can delay treatment
•Concern over presence of herniation can lead to more extensive
surgery
•Anterior decompression, and if then reduction not achieved,
posterior reduction and fusion and then anterior reconstruction

Cervical Facet Dislocation: When is MRI Indicated?
Hart, Vaccaro & Nachwalter SPINE 2002

17. Reduction or MRI
•Answers from the literature
•Does early decompression improve the outcome?
•Probably
•Delay for MRI is relevant
•Does neurological deterioration occur with closed reduction?
•Rarely
•Closed reduction is safe (?)
•Does disc herniation predispose to neurological deterioration
•Probably not
•No need to identify herniation before reduction (?)
•Does MRI predict outcome or guide treatment?
•Probably not
•Obtaining MRI is not useful (?)

18. Reduction or MRI
•Position
•Immediate reduction is indicated in early presentation with
significant neurological deficit
•Chance of improvement in deficit
•Little risk of making patient worse
•MRI is indicated in late presentation
•Delay unlikely to be significant
•Can help plan surgery
•Most controversial situation is early presentation with normal
neurology or only minimal deficit

19. MRI first
AGAINST

Delays treatment

Risk of displacement during
transfer or scan

Interpretation variable

If HNP present
Neurological injury can occur
during open reduction

FOR

Delay unlikely to affect outcome

Patient acts as neurological
monitor

MRI result gives useful
information

Avoids risk of neurological injury
during closed reduction

20. Reduction first
FOR

Theoretical increased chance of
neurological improvement

Very low risk of neurological
deterioration

Presence of disc prolapse not
proven to increase risk

Neck stable and cord
decompressed so surgery
elective
AGAINST

Benefit unproven


Devastating outcome has been
reported

Disc prolapse implicated in
neurological deterioration

Likelihood of further injury while
waiting for surgery low

21. Reduction or MRI
•Consensus statement
•MRI indicated prereduction in
•Patients with altered mental state where closed reduction
contraindicated
•Late presentation where immediate reduction more difficult and
unlikely to change outcome
•Failed closed reduction (before open reduction)
•Immediate closed reduction in
•Patients with significant neurological deficit
•Contentious in
•Patients with minimal or no neurological deficit
•“Do you want to know about the status of the disc or do you
want to reduce the dislocation quickly?”
•I recommend closed reduction in experienced hands

23. Excellence in Spine