Mechanism of severe neurologic
complications after steroid epidural injections
Jean-Denis Laredo
&
Hervé Bard
Mechanism of severe neurologic complications
after steroid epidural injections
• Different for cervical versus lumbar steroid
epidural injections
Mechanism of severe neurologic
complications after steroid epidural injections
• Cervical steroid epidural injections
Epidural hematoma
Intramedullary injection
Infection
Spinal cord infarction due to vascular ischemia
2/ Cervical spinal cord infarct:
Cervical radiculo-medullary artery
1/ cerebellar infarct:
Vertebral artery territory
Lumbar epidural steroid injection (LESI)
Mechanism of severe neurologic
complications after steroid epidural injections
• Cervical steroid epidural injections
• Lumbar steroid epidural injections
Spinal cord infarction due to vascular ischemia
MRI: 6 hours post 24hours
Variability of the infarct extent
A constant finding in permanent neurologic
deficits complicating Lumbar ESI:
spinal cord-conus medullaris vascular infarction
Arterial supply of the
spinal cord
• One main anterior spinal artery Supplied by 5 to 7 Radiculo-
medullary arteries
• Two posterolateral arteries
Anterior view posterior view
Arterial supply to the spinal cord
• 32 pairs of metameric radicular arteries
• 3 kind of metameric radicular arteries
– 5 to 7 Radiculo-medullary arteries,
supplying the anterior and the 2
posterolateral spinal arteries
– Radiculo-pial arteries participating to
the “vasa corona”, metameric
distribution
– Plain metameric radicular arteries
• All the arterial supply to the spinal cord is provided
by radiculo-medullary arteries penetrating the
spinal canal through an intervertebral foramen
Arterial supply of the spinal cord
Arterial supply to the lumbosacral spinal
cord and conus terminalis
• In 75% of cases the radiculomedullary artery (RMA) of
the lumbosacral cord and conus terminalis (Adamkiewicz
artery) arises between T9 and T12, and from the left in
69% of the cases.
• When the Adamkiewicz artery arises above T9, there is
usually an additional lumbar or sacral RMA (Desproges-
Gotteron artery).
Arterial supply to the lumbar spinal cord
Consequences for lumbosacral steroid injections
• All the lumbar and anterior sacral intervertebral foramens,
especially on the left side, may contain a radicular artery
participating to the arterial supply of the conus terminalis
and eventually to the “crucial arcade”
Arterial supply to the conus medullaris
• “Anse anastomotique
remarquable” (“crucial
arcade”), around the conus
terminalis, similar to Willis
polygon, which anastomoses
the anterior with the 2
posterolateral spinal arteries
Pathogenesis of the spinal cord infarction : Arterial rather than venous pathway
Thrombosis
Vasospasm
Vascular compression
Vascular embolization by steroid aggregates
Mechanism of severe neurologic
complications after steroid epidural injections
Tiso RL et al, Spine J (2004)
Okabadejo GO et al, JBJS (2008)
Neurologic deficits after LESI Common clinical findings
• Indication of the LESI : sciatica or femoral pain
(&LBP) due to degenerative disease
• Fluoroscopy or CT guidance
• After a few seconds/minutes:
Intense abdominal &/or leg pain
Sometimes malaise and flush
Followed by rapid installation of the motor deficit
• 8 cases among 12 (66,6%)
• LESI on a post-op spine: only 8% of LESI in our
institution
• Needle approach : 6 foraminal, 1 interlamar, 1 apophyseal
joint injections
• Review of 6 cases : needle tip close to the scar 6/6
• Intervertebral level: L1-2, L3-4, L4-5, L5-S1
• Side: 7G, 1D
Wybier M et al, Eur Radiol 2010
Neurologic deficits after LESI on a post-op
spine
prior contrast inj. post contrast inj.
Neurologic deficits after LESI on a post-op spine
Role of the postoperative epidural scar ?
+
=
+
Tiso RL et al, The spine J, 2004
Permanent
neurologic
deficits
following
LESI (n=12)
Steroid suspension Elementary
particule
size (µ)*
Tendancy to
coalesce*
Aggregate
size (µ)*
France (n=6)
Prednisolone acetate
HydrocortancylR
2-4
++++
30-120
USA (n=1)
Betamethasone acetate
Celestone SolupsanR
Celestone ChronodoseR
BetnesolR
10
+
20-30
USA (n=2)
UK (n=1)
Triamcinolone acetonide
KenalogR, KenacortR
TedarolR
2-4
++
40-80
USA (n=2)
Methylprednisolone
acetate
DepomedrolR
2
++
20-40
Steroid suspensions
Aggregate size
• USA DepomedrolR >50µ: 25% >1000µ: 5%
KenalogR >50µ: 25% >1000µ: 1%
Celestone SolupsanR >50µ: 25% >1000µ: 0%
• France Hydrocortancyl 125R mean 30-120µ
AltimR few small aggregates
Benzon H, Anesthesiology 2007
Tiso RL, The Spine J, 204
Roques CF, Rhumatologie 1987
Steroid suspensions
Tendancy to form particule aggregates
• USA DepomedrolR ++
KenacortR, KenalogR ++
Celestone SolupsanR +
• France Hydrocortancyl 125R ++++
AltimR + Benzon H, Anesthesiology 2007
Tiso RL, The Spine J, 204
Roques CF, Rhumatologie 1987
Mechanism of severe neurologic
complications after LSEI
• Spinal cord infarction due to vascular ischemia
• Pathogenesis hypotheses 1. Obliteration of a radiculomedullary artery by aggregates of
steroid particles
2. Deformation and agglutination of Red Blood cells
when mixed with particulate steroids
Red Blood cells agglutination
when mixed with particulate steroids: RBC agglutination
ALTIM
HYDROCORTANCYL
KENALOG
DEPOMEDROL
GROUPE SANGUIN A AB O
Pathway of the steroid to the spinal cord
1. Radiculo-medullary artery
2. Unknown arteriovenous fistula
2 février 2017 - Rupture altim -
infiltration épidurale
50
Normal arteriovenous anastomoses
• Nerve roots receive en arterial supply from both ends through longitudinal peri- and intraradicular arteries that anastomose in the midsections of the radicular fascicules.
• Numerous and relatively large normal arteriovenous anastomoses throughout the length of each root protect the functionnal integrity of the radicualr circulation in the event of focal compressions
53
Role of epidural and radicular veins in chronic back pain
and radiculopathy. Wesley W Parke. In: Arthroscopic and
Endoscopic Spinal Surgery. Ed: kambin P. Humana Press
Inc. Totowa, NJ
2 février 2017 - Rupture altim -
infiltration épidurale
54
2 février 2017 - Rupture altim -
infiltration épidurale
55
56
57
Pathway of the steroid to the spinal cord
1. Radiculo-medullary artery
2. Unknown arteriovenous fistula
3. Venous pathway ?
May explain neurologic complications
after posterior (interlaminar/interspinous)
epidural injections in the postoperative spine
2 février 2017 - Rupture altim -
infiltration épidurale
58
• addendum
Etude Study formate Biais Evaluation Results
Kennedy et al RCT
Unilateral NRP
Unilevel HD
78 pts
total
N°inj
Surgery
NS but 1.6 inj for DXM
Vs 1.4 for TC.17% DXM
vs1% TC needed 3inj
Kim & Brown 2011 RCT 30 pts
total
NS but Trend toward
less relief & shorter
duration
Park et al 2010 RCT Triamcinolone vs DXM Foraminal 106 pts
VAS TC: 8.3 2.4 at 1M
DXM: 7.4 4.1(stat si)
McGill pain,ODI: no diff
El Yagouchi 2013 Retrospective
3645 foraminal
NS
Dreyfus et al. 2006 RCT
Cervical
NS
Ahadian FM et al.
Reg Anesth Pain
Med 2011;36:572
DXM 4/8/12mg No differences
Kim et al. Clin J Pain. 2011
Sequential Triamcinolone then DXM
Delayed oral patient interview
Patient preference Inj-free interval
Higher % pts prefer TC Inj-free interval 91d/77 Disc Hern 105days/78 Foram app 89days/67
Mehta et al. PM R. 2016
Review Pain, function
NS
Shakir et al. Am J Phys Med Rehabil. 2013 Sep.
Cohort VAS NS
Lee et al. Skeletal Radiol. 2009 Nov.
Cohort VAS NS
Paraplegia complicating caudal epidural steroid injection
• Somanchi BV,Mohammad S, Ross R. An unusual
complication following caudal epidural steroid injection: a
case report. Acta Orthop Belg 2008; 74(5):720-2
Paraplegia complicating DXM epidural steroid injection
• Gharibo C, Fakhry M, Diwan S, Kaye AD. Conus
medullaris infarction after a right L4 transforaminal
epidural steroid injection using dexamethasone. Pain
Physician 2016;19:E1211-E1214
• Man 60yo. NRP for 3 years. No previous surgery
• L4 Transforaminal injection of Dexamethasone (exact
brand not provided)
PEG BENZYLIC A. PARABEN BISULFITES
DEPOMEDROL
40-80 ®
Méthylprédnisolone
acétate + + - -
KENALOG® Triamcinolone acétonide - + - -
KENACORT
40-80 ®
Triamcinolone acétonide - + - -
CELESTONE
SOLUSPAN®
Bétamétasone
Sodium phosphate - - - -
DIPROSTENE® Bétamétasone
Sodium phosphate + + - -
ALTIM® Cortivazol - + - - DECADRON® Dexaméthasone sodium
phosphate - - + +
STOP
- 7M et 5F
- 58 ans (40 - 78), médiane 64 ans
- 8 rachis opérés et 4 rachis non opérés
- 10 injections du côté gauche, 2 à droite
- 10 foraminales, 1 interlamaire, 1 para-articulaire
postérieure
- T12-L1 (n=1) L1-2 (n=1) L2-3 (n=1) L3-4 (n=3) L4-5 (n=3) L5-S1 (n=3)
Analyse des 12 cas:
Wybier M et al. Eur Radiol 2010
SANOFI CLINICAL TRIAL Main proposal Alternative/compl
Adult 30-55
Adult 25-50
Clinical indication Acute-subacute NRP
(leg pain>back pain) due
to HD
Spinal stenosis
Plurirad/monorad
Pain duration Min- Max: 2W to 3M Min- Max: 3W to 6M
Spine approach Interlaminar
(W palmer technique)
Foraminal
Treatment 1/Epidural Lidocaïne
2/DXM no excipient
Epidural saline
Subcutaneous saline
Particulate No excipient
Primary endpoint Pain (VAS) Second: need for add
injections /cross-over
Timeline 1W, 3W And 6W
Cross-over Yes after 3W No
Yes after 6W