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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_6009_Библиотеки_им_академика_М_И_Перельмана.pdf
Selective Nerve Root Block, Cervical Spine
KEY FACTS
TERMINOLOGY
• Selective anesthesia of cervical nerve root at level of neural
foramen
PREPROCEDURE
• Radiculopathy corresponding to cervical dermatome
PROCEDURE
• Target
Image-Guided Procedures
○ Superior articular process of same number vertebra as
nerve being injected (nerve comes out 1 level above)
○ At level of superior articular facet, deflect needle
anteriorly into neural foramen
○ Verify needle tip placement within neural foramen in
frontal and lateral projections
• Slowly inject iodinated contrast to confirm correct needle
placement if no contraindication
○ Should see contrast track along nerve root
Anatomy: Coronal Graphic Anatomy: Sagittal Graphic
(Left) Coronal graphic shows
relationship of exiting nerve
roots to cervical vertebrae.
The C1 nerve root exits
between the occipital bone
and C1, and the C8 nerve root
ſt exits via the C7/T1 neural
foramen. (Right) Parasagittal
graphic shows the anatomic
relationship of the cervical
nerve roots surrounded by
adipose tissue to the
accompanying artery ſt and
vein . Note the relationship
to the superior articular facet
(anatomic landmark) for
cervical selective nerve root
block (SNRB).
○ May see contrast track beneath pedicle and into epidural
space (transforaminal epidural steroid injection)
○ Should not see vascular enhancement, contrast pooling,
or feathering within skeletal muscle
○ Use nonparticulate steroid preparation to minimize
vascular complications
• Alternative procedure: Interlaminar epidural steroid
injection
POST PROCEDURE
• Pain assessment
○ Note pain before, during, and after injection and
whether characteristic pain was reproduced
OUTCOMES
• Vasovagal reaction
• Most feared complications
○ Stroke, spinal cord puncture, hematoma
440
C6 Selective Root Block Contrast Injection
(Left) Posteroanterior
fluoroscopic spot radiograph,
following needle
placement for right C6 SNRB
and contrast injection, shows
contrast tracking along the
exiting right C6 nerve root .
(Right) Axial CT following
injection of myelography-safe
iodinated contrast shows
contrast within the neural
foramen ſt without extension
into the subarachnoid or
epidural space. Aspiration
confirmed extravascular
placement. Steroid injection
was then performed.
Selective Nerve Root Block, Cervical Spine
TERMINOLOGY
Synonyms
• Cervical selective nerve root block (CSNRB)
Definitions
• Selective anesthesia of cervical nerve root at level of neural
foramen
PREPROCEDURE
Indications
• Radiculopathy, chronic neck pain
• Acute exacerbation of chronic neck pain
Contraindications
• Local or systemic infection
• Coagulopathy
• Allergy to injectate
• Relative: Iodinated contrast allergy, pregnancy, active
hepatitis
Getting Started
• Things to check
○ Prior imaging: Causative lesion; multilevel vs. single-level
disease
○ Coagulation parameters as indicated
○ Informed consent
• Medications
○ Corticosteroid
○ Short- and long-acting anesthetic
○ Iodinated contrast (myelography-safe)
Image-Guided Procedures
• Deflect needle tip anteriorly, and advance slowly into
neural foramen
○ Be prepared for patient to jump &/or vocalize if nerve
root is hit
• Verify needle tip placement within neural foramen in
frontal and lateral projections
• Remove stylette, and observe hub for blood
• Slowly inject iodinated contrast to confirm correct needle
placement if no contraindication
○ Should see contrast track along nerve root
○ May see contrast track beneath pedicle and into epidural
space (transforaminal epidural steroid injection)
○ Should not see vascular enhancement, contrast pooling,
or feathering within skeletal muscle
• Attach 3-mL syringe containing injectate
• Inject slowly: Use nonparticulate steroid preparation
○ If not possible to inject due to resistance from contrast,
attach 1-mL syringe containing portion of injectate, and
inject to clear contrast from needle
• Remove needle, and obtain hemostasis
Findings and Reporting
• Change in patient's pain following injection
• Whether epidural injection was also noted during contrast
injection
• Any complications
Alternative Procedures/Therapies
• Radiologic
○ Interlaminar epidural steroid injection
– Bilateral, multifactorial stenosis affecting multiple
nerve roots
PROCEDURE
Patient Position/Location
• Best procedure approach
○ Supine position
– Visualizing mid to lower cervical spine on lateral
fluoroscopy may be difficult due to shoulder position
□ Have patient hold each end of rolled sheet pulled
taught against feet with knees flexed at ~ 45°
□ Holding sheet, extend knees to use legs to hold
shoulders stretched downward
○ Lateral approach
– Must have true lateral fluoroscopic view of cervical
vertebrae
– Align vertebral and facet joint margins
○ Target
– Superior articular process of same number vertebra as
nerve being injected (nerve comes out 1 level above)
– At level of superior articular facet, deflect needle
anteriorly into neural foramen
• "Time out"
○ Verify correct patient, procedure, and side to be injected
○ Verify all necessary equipment is readily available
Procedure Steps
• Verify needle trajectory to target in PA and lateral
projections
• Intermittently advance needle, and verify under
fluoroscopy until anterior margin of superior articular
process is reached
POST PROCEDURE
Expected Outcome
• Improvement in pain
Things to Do
• Remind patient of potential late complications
• Remind patient to log pain/relief of pain between clinical
visits (pain diary)
• Establish follow-up
OUTCOMES
Problems
• Vasovagal reaction
Complications
• Most feared complication(s)
○ Intravascular injection/stroke
○ Spinal cord injury/intraspinal hematoma
• Other complications
○ Bleeding, infection, nerve root injury
441
Epidural Steroid Injection, Cervical Spine
KEY FACTS
TERMINOLOGY
• Percutaneous injection of glucocorticoid into cervical
epidural space
○ Interlaminar: Approach epidural space between lamina
○ Transforaminal: Approach epidural space via neural
foramen
PREPROCEDURE
Image-Guided Procedures
• Indication
○ Cervical pain &/or cervical radiculopathy
• Coagulopathy
• Preprocedure imaging
○ Assess adequate epidural space to accommodate needle
placement/injection
PROCEDURE
• Loss of resistance/free injection of saline reveals tip in
epidural space (or intrathecal)
○ Inject contrast to verify needle tip placement
(Left) Sagittal graphic of the
cervical spine and cervical
spinal cord shows a thin layer
of epidural fat
representing the epidural
space just deep to the spinous
processes/spinolaminar line
ſt. (Right) Anteroposterior
fluoroscopic spot radiograph
shows the needle tip near the
midline in the cervical epidural
space, entering from an
interlaminar approach.
Contrast typically shows
Christmas tree appearance
and outlines the epidural
space ſt. Note the lamina
and spinous process st at the
level of puncture.
POST PROCEDURE
• Expectation
○ Improvement in, or eradication of, pain at level of
injection
○ Steroid may take 48-72 hours to reach maximum
therapeutic effect
OUTCOMES
• Most feared complications
○ Direct spinal cord injury or intraspinal hematoma
○ Intrathecal injection of anesthetic/respiratory paralysis
Normal Anatomy Needle Placement: Epidural Injection
442
Cervical Epidurogram: Lateral View Complication: Cord Puncture
(Left) The lateral view shows
the expected appearance of an
interlaminar epidural injection
ſt. Note the amorphous
pattern of spread, deep to the
spinolaminar line , which
appears distinctly different
than cervical myelography.
(Right) Axial CT following
percutaneous cervical spine
intervention shows focal
contrast accumulation within
the cervical spinal cord ſt. A
small amount of epidural gas
is also seen following
inadvertent cord puncture.
Epidural Steroid Injection, Cervical Spine
TERMINOLOGY
Abbreviations
• Epidural steroid injection
Definitions
• Injection of corticosteroid percutaneously into epidural
space
○ Interlaminar: Approach epidural space between lamina
(C7-T1 level preferred)
○ Transforaminal: Approach epidural space via neural
foramen
PREPROCEDURE
Indications
• Cervical pain &/or cervical radiculopathy
Contraindications
• Coagulopathy
• Systemic or localized infection at site of planned injection
• Allergy to injectate
Getting Started
• Medications
○ Corticosteroid
– Long-acting anesthetic not injected, as respiratory
paralysis may result
○ Short-acting local anesthetic
PROCEDURE
Patient Position/Location
• Best procedure approach
○ Prone
– Slight angulation of AP fluoroscopy tube for
delineation of lamina/interlaminar space
– True lateral fluoroscopy helpful for needle depth
Procedure Steps
• Preprocedure "time out": Correct patient, side of injection,
and procedure
• Position patient as comfortably as possible with supporting
pillows
○ Conscious sedation is generally not provided, as it is
believed to be safer for patient to be alert and fully able
to notify interventionalist immediately of new or unusual
pain during procedure
• Angle fluoroscopy tube to maximize visualization of
interlaminar space
• Mark correct level at cephalad margin of lamina near
junction with spinous process
• Create skin wheal, and carefully anesthetize deeper
subcutaneous tissues
• Place epidural needle into subcutaneous tissue with curved
tip projecting cephalad
• Slowly advance needle to lamina under intermittent
imaging
• Once lamina is reached, carefully direct needle tip cephalad
and "walk" off cephalad edge of lamina
• Attach glass syringe containing preservative-free saline
• Slowly advance epidural needle, testing with gentle
plunging of glass syringe while slowly advancing
○ Loss of resistance/free injection of saline reveals tip in
epidural space (or intrathecal)
• Attach contrast syringe/tubing to needle
• Warn patient, then inject contrast to verify needle tip
placement within epidural space
• Once confirmed, document with radiographic images
• Mix, then attach injectate syringe
• Warn patient, then slowly inject, noting intensity and
character of pain produced
Findings and Reporting
• Character and severity of patient pain before, during, and
after procedure
Alternative Procedures/Therapies
• Radiologic
○ Selective nerve root block
– Generally for 1- or 2-level unilateral or 1-level bilateral
radicular symptoms
• Surgical
○ Decompression
• Other
○ Neurolysis
○ Percutaneous disc ablation/discectomy
POST PROCEDURE
Expected Outcome
• Improvement in or eradication of pain at level of injection
○ Patients often describe numbness/heaviness in side
injected
• Pain may increase as local and long-acting anesthetic wear
off
○ Steroid may take 48-72 hours to reach maximum
therapeutic effect
Things to Do
• Assess patient after injection, and assist from table when
ready
○ Patients can often be discharged within 30 minutes after
procedure if feeling well
OUTCOMES
Problems
• Failure of injection to provide symptomatic relief
○ Relief may not be experienced for 48-72 hours following
injection
Complications
• Most feared complication(s)
○ Spinal cord puncture/cord hematoma
○ Compressive epidural hematoma
○ Intrathecal injection of anesthetic/respiratory paralysis
SELECTED REFERENCES
1. Huston CW: Cervical epidural steroid injections in the management of
cervical radiculitis: interlaminar versus transforaminal. A review. Curr Rev
Musculoskelet Med. 2(1):30-42, 2009
2. Kim KS et al: Fluoroscopically guided cervical interlaminar epidural injections
using the midline approach: an analysis of epidurography contrast patterns.
Anesth Analg. 108(5):1658-61, 2009
3. Malhotra G et al: Complications of transforaminal cervical epidural steroid
injections. Spine (Phila Pa 1976). 34(7):731-9, 2009
Image-Guided Procedures
443
Medial Branch Block, Thoracic Spine
KEY FACTS
TERMINOLOGY
• Selective anesthesia of thoracic spinal nerve medial branch
in assessment of thoracic facet joint pain
PREPROCEDURE
• Thoracic facet joint pain
○ Confirm clinical suspicion (diagnostic)
○ Evaluate likelihood of successful facet neurolysis
Image-Guided Procedures
• Preprocedure imaging
PROCEDURE
• Target
○ Immediately above transverse process/superior articular
process junction
– Be sure to avoid lung
○ Carefully approach medial branch as close as possible to
lateral aspect of superior articular process
• Record pain score
○ Before, during, and after injection for each level
(Left) Sagittal CT shows
hypertrophic changes of
thoracic facet joints with bony
overgrowth ſt encroaching
on the dorsal aspect of the
neural foramina . Note the
anterior compression fractures
st. (Right) Oblique view
shows the needle tip ſt
directed toward the junction
of the superior articular
process and transverse
process st. Oblique view
should provide excellent
visualization of the "Scotty
dog." At higher levels, careful
attention to lung margins is
essential.
POST PROCEDURE
• Expected outcome: Significant reduction in pain associated
with target facet joint
○ < 100% pain reduction reduces likelihood of successful
neurolysis
OUTCOMES
• Problem: Failure of pain reduction
○ Facet joints not sole pain generator
○ Inaccurate needle placement
• Complications
○ Vasovagal reaction
○ Pneumothorax
○ Spinal/nerve cord injury
• Alternative procedures
○ Physical therapy
○ Neurolysis
○ Thoracic facet joint injection(s)
Anatomy Needle Placement: Oblique View
444
Needle Placement: Frontal View Needle Placement: Lateral View
(Left) Anteroposterior
fluoroscopic spot radiograph
shows needle tips ſt angled
slightly laterally, along the
transverse process . A
diagnostic block performed
here is helpful to determine
candidacy for ablation
secondary to left T12/L1 facet
joint st pain. (Right) Lateral
fluoroscopic image shows the
relationship of well-positioned
needle tips relative to the
transverse process st. Note
the well-circumscribed
vertebral margins ſt and
neural foramen .
Medial Branch Block, Thoracic Spine
TERMINOLOGY
Abbreviations
• Superior articular process (SAP)
Definitions
• Selective anesthesia of thoracic spinal nerve medial branch
in assessment of thoracic facet joint pain
PREPROCEDURE
Indications
• Thoracic facet joint pain
○ Confirm clinical suspicion (diagnostic)
– Clinical exam often unreliable in assessment of facet
joint pain
○ Determine likelihood of successful facet neurolysis
• Acute or chronic thoracic back pain
• Facet joint osteoarthritis
Contraindications
• Coagulopathy
• Local or systemic infection
Getting Started
• Things to check
○ Laboratory data
– Signs of infection or impaired coagulation
○ Informed consent
• Medications
○ Short-acting anesthetic
○ Long-acting anesthetic
○ ± corticosteroid
○ Iodinated contrast (myelography-safe)
PROCEDURE
Patient Position/Location
• Best procedure approach
○ Prone
– Target is junction of superior articular process and
transverse process
□ Carefully approach medial branch as close as
possible to lateral aspect of superior articular
process
Procedure Steps
• Create skin wheal with local anesthetic and anesthetize
subcutaneous tissues
• Anchor 22-gauge spinal needle in subcutaneous tissue and
check trajectory under fluoroscopy or CT
• Carefully advance needle under intermittent imaging
guidance
○ Be sure to avoid lung
• Target
○ Immediately above transverse process/SAP junction
• Remove stylette and observe hub for blood
○ If blood present, reposition needle slightly
○ If no blood, proceed
• Attach injectate syringe
• Record patient's pain
○ Before, during, and after injection
Image-Guided Procedures
• Repeat steps for each additional level as indicated
Findings and Reporting
• Level(s) injected
• Pain score
○ Before, during, and after injection for each level
• Component(s) of injectate
• Complications
Alternative Procedures/Therapies
• Radiologic
○ Thoracic facet joint injection(s)
• Surgical
○ Fusion
• Other
○ Neurolysis
○ Conservative management
○ Physical therapy
POST PROCEDURE
Expected Outcome
• Significant reduction in pain associated with target facet
joint
○ < 100% pain reduction reduces likelihood of successful
neurolysis
Things to Do
• Ensure that clinical follow-up is established
• Remind patient to keep a pain diary until next clinic visit
Things to Avoid
• Bathing for 48-72 hours
OUTCOMES
Problems
• Vasovagal reaction
• Failure of pain reduction
○ Facet joints not sole pain generator
○ Inaccurate needle placement
Complications
• Most feared complication(s)
○ Pneumothorax
○ Dural puncture
– Spinal cord injury
– Epidural/subdural hematoma
○ Meningitis
• Other complications
○ Bleeding
○ Local infection
○ Nerve root injury
SELECTED REFERENCES
1. Atluri S et al: Systematic review of diagnostic utility and therapeutic
effectiveness of thoracic facet joint interventions. Pain Physician. 11(5):61129, 2008
2. Manchikanti L et al: Effectiveness of thoracic medial branch blocks in
managing chronic pain: a preliminary report of a randomized, double-blind
controlled trial. Pain Physician. 11(4):491-504, 2008
3. Verrills P et al: The incidence of intravascular penetration in medial branch
blocks: cervical, thoracic, and lumbar spines. Spine (Phila Pa 1976).
33(6):E174-7, 2008
445
Facet Joint Injection, Thoracic Spine
KEY FACTS
TERMINOLOGY
• Injection of long-acting anesthetic ± corticosteroid into
thoracic facet joint
PREPROCEDURE
• Preprocedure imaging
○ Correlate level with prior imaging
– Evaluate for 12 ribs &/or transitional vertebral
Image-Guided Procedures
anatomy
• Indications for procedure and future treatment plan
○ Is facet joint injection or medial branch block more
appropriate?
PROCEDURE
• Fluoroscopy
○ Align margins of facet joint to maximize visualization of
joint space
○ Contrast is useful to evaluate intraarticular injection
during fluoroscopy-guided facet injection
(Left) Image from an axial CT
myelogram shows
characteristic findings of facet
joint osteoarthritis, including
sclerosis with irregularity of
the facets ſt and vacuum
phenomenon within the joint
space(s) . (Right) Oblique
view obtained during leftsided injection shows
extraarticular contrast
from earlier injection with
intraarticular opacification ſt
after the needle was advanced
into the joint space.
• CT
○ Gantry angulation may be necessary to "open" facet
joints
○ Sagittal reformats helpful for determining correct level
and angulation of needle
POST PROCEDURE
• Improvement/relief of pain referable to facet joint(s)
injected
○ < 100% pain relief decreases likelihood of successful
outcome following facet neurolysis/radiofrequency
ablation
OUTCOMES
• Most feared complications
○ Spinal cord/nerve root injury
○ Pneumothorax
○ Epidural hematoma
Degenerated Facets Needle Placement
446
Intraarticular Needle Placement Intraarticular Needle Placement
(Left) Axial NECT shows the
position after "walking" the
needle slightly lateral and
cephalad, at which time the
needle was felt to "pop" into
the joint space. This image
now confirms that the needle
tip lies within the facet joint
ſt. (Right) Sagittal
reformatted NECT confirms
intraarticular needle tip
placement ſt as seen in the
previous axial image. Two
planes of imaging are very
helpful for confident
determination of needle tip
positioning, particularly if
contrast injection is not being
performed.
Facet Joint Injection, Thoracic Spine
TERMINOLOGY
Abbreviations
• Facet joint injection (FJI)
Definitions
• Injection of long-acting anesthetic ± corticosteroid into
thoracic facet joint
PREPROCEDURE
Indications
• Thoracic facet joint osteoarthritis
○ Chronic or acute exacerbation of thoracic facet joint pain
Contraindications
• Coagulopathy
• Local or systemic infection
• Severe allergy to components of injectate
Getting Started
• Things to check
○ Preprocedure imaging
– Look for facet joint degenerative changes, correlate
correct level
○ Indications for procedure/plan for definitive treatment
– Median branch block vs. FJI
○ Coagulopathy
○ Informed consent
PROCEDURE
Patient Position/Location
• Best procedure approach
○ Prone
Equipment Preparation
• Fluoroscopy
○ Align margins of facet joint to maximize visualization of
joint space
• CT
○ Gantry angulation may be necessary to "open" facet
joints
Procedure Steps
• Procedure "time out"
• Carefully determine correct level for injection
• Mark skin, and perform sterile prep and drape
• Apply local anesthetic, and assess trajectory to facet joint
with fluoroscopy or CT
• Place spinal or Chiba needle into dorsal subcutaneous
tissue, and reassess trajectory to facet joint
• Under intermittent fluoroscopy or CT imaging, advance
needle until "pop" into joint or firm bone is felt
• Assess needle placement on oblique and lateral
fluoroscopy or CT
• If necessary, "walk" needle into facet joint, and reassess
with imaging
• Attach contrast syringe/tubing
○ Useful to evaluate extravascular, intraarticular injection
during fluoroscopy-guided facet injection
○ ± for CT-guided injection
Image-Guided Procedures
• Aspirate gently to confirm extravascular, then slowly inject
contrast to confirm intraarticular needle tip placement
○ Inject minimal amount of contrast to confirm needle
position
• Mix injectate, attach, then slowly inject facet joint
○ 0.5-1.5-mL injection volume is generally sufficient
• Note symptoms during and after injection
Alternative Procedures/Therapies
• Radiologic
○ Medial branch block
• Surgical
○ Fusion
POST PROCEDURE
Expected Outcome
• Improvement/relief of pain referable to facet joint(s)
injected
○ < 100% pain relief decreases likelihood of successful
outcome following radiofrequency ablation
OUTCOMES
Problems
• Failure of pain relief
○ Facet joint not pain generator
○ Wrong level(s) injected
○ Extraarticular injection
• Vasovagal reaction
Complications
• Most feared complication(s)
○ Spinal cord/nerve root injury
○ Pneumothorax
○ Epidural hematoma
• Other complications
○ Bleeding
○ Infection
SELECTED REFERENCES
1. Peterson C et al: Evidence-based radiology (part 1): is there sufficient
research to support the use of therapeutic injections for the spine and
sacroiliac joints? Skeletal Radiol. 39(1):5-9, 2010
2. Sehgal N et al: Systematic review of diagnostic utility of facet (zygapophysial)
joint injections in chronic spinal pain: an update. Pain Physician. 10(1):213-28,
2007
3. Boswell MV et al: Accuracy of precision diagnostic blocks in the diagnosis of
chronic spinal pain of facet or zygapophysial joint origin. Pain Physician.
6(4):449-56, 2003
447
Selective Nerve Root Block, Thoracic Spine
KEY FACTS
TERMINOLOGY
• Selective corticosteroid and long-acting anesthetic injection
of thoracic nerve root at level of neural foramen
PREPROCEDURE
• Indications
○ Thoracic radiculopathy
○ Persistent pain after vertebroplasty/kyphoplasty
Image-Guided Procedures
○ Neoplastic compression of thoracic nerve root
PROCEDURE
• Use nonparticulate steroid to minimize vascular risk
• C-arm angulation must permit visualization of medial
pleural surface of lung during procedure
• CT offers improved soft tissue and lung visualization
○ Sagittal/coronal reformatted CT may facilitate difficult
needle placement
Cervical Root Numbering Vertebral Body Numbering
(Left) Coronal graphic depicts
the cervical nerve roots
exiting above their
corresponding pedicle, while
thoracic (and lumbar) nerve
roots st exit below. Note the
C8 nerve roots ſt. (Right)
Anteroposterior fluoroscopic
spot radiograph was obtained
prior to thoracic spine
intervention. Careful
numbering of the ribs or
vertebrae after assessing the
entire spine for transitional
anatomy is critical.
POST PROCEDURE
• Report pain intensity before, during, and after injection
OUTCOMES
• Expected: Significant improvement in pain
• Potential problem: Failure of pain relief
○ Technical failure: Injection not properly localized or
wrong level injected
○ Clinical failure: Thoracic nerve root not sole pain
generator
• Most feared complications
○ Vascular injury
– Spinal cord ischemia from compromise of artery of
Adamkiewicz
○ Pneumothorax, dural puncture
○ Spinal cord puncture or compression secondary to
hematoma
448
Foraminal Injection: Transforaminal
Epidural Steroid Injection Needle Placement: CT
(Left) Fluoroscopic spot
radiograph after needle
placement st shows contrast
within right thoracic neural
foramen ſt. Note linear
extension along exiting nerve
root and medial extension into
epidural space . Note also
the pedicles and spinous
process . (Right) Axial NECT
shows the needle tip
placed at the posterior margin
of the neural foramen ſt.
Note dramatically improved
visualization of lungs and
other soft tissue structures
with CT-guided thoracic
procedures.
Selective Nerve Root Block, Thoracic Spine
TERMINOLOGY
Abbreviations
• Selective nerve root block (SNRB)
Definitions
• Selective corticosteroid and long-acting anesthetic injection
of thoracic nerve root at level of neural foramen
PREPROCEDURE
Indications
• Thoracic radiculopathy
○ Thoracic spine degenerative disease
○ Posttraumatic osteoarthritis
○ Persistent pain after vertebroplasty/kyphoplasty
○ Neoplastic compression of thoracic nerve root
Contraindications
• Coagulopathy
• Evidence of local or systemic infection
• Severe allergy to components of injectate
Preprocedure Imaging
• Evaluate causes of pain
○ e.g., nerve root displacement/compression by
degenerative or neoplastic disease
• Gain familiarity with patient-specific anatomic relationships
○ Vertebral or facet joint fusion anomalies
– Severe hypertrophic facet changes may make access
to neural foramen challenging
○ Transitional lumbosacral anatomy
– Must carefully assess anatomy to ensure injection is at
correct level
○ Cervical ribs
– Must carefully assess anatomy to ensure injection is at
correct level
○ Scoliosis
– May require change in patient positioning
Getting Started
• Things to check
○ Laboratory data
– Evidence of coagulopathy
– Evidence of infection/inflammation
□ White blood cell count (WBC), recent febrile illness,
cultures if available
○ Informed consent
• Medications
○ Short- and long-acting anesthetic
○ Corticosteroid
○ Radiographic contrast (myelography-safe)
PROCEDURE
Patient Position/Location
• Best procedure approach
○ Prone
Procedure Steps
• Procedure "time out"
○ Correct patient
○ Correct side
Image-Guided Procedures
○ Correct procedure
○ All necessary equipment present
• Carefully determine correct level
○ Nerve root exits beneath pedicle of same numbered
thoracic vertebra
• Mark skin, allowing for needle trajectory that is medial to
pleural margin
• Perform sterile prep and drape
• Create skin wheal, and anesthetize deep subcutaneous
tissues
• Anchor 22-gauge needle in subcutaneous tissue
• Carefully advance needle under intermittent imaging
guidance
○ Alternating oblique, AP, and lateral fluoroscopy to
ensure knowledge of needle depth and relationship of
needle to pleural surface
• If bone is reached, reassess with imaging, and "walk" needle
into foramen
○ Most frequent barrier is needle placement against facet
(posterior or superficial to neural foramen)
• When needle slips into foramen, reassess with imaging
○ Tip should be beneath lateral pedicle cortex on frontal
radiograph and in foramen on lateral view
○ Always assess for evidence of pneumothorax
• Inject contrast slowly
○ Look for vascular enhancement/flow
○ Contrast should outline nerve
○ Look for signs of transforaminal epidural steroid
injection
– Contrast spreading beneath/medial to pedicle into
epidural space
• Remove contrast syringe/tubing, and attach injectate
syringe
○ Mix injectate immediately prior to attaching
• Slowly inject injectate
○ Determine pain intensity (1-10) during and after injection
POST PROCEDURE
Expected Outcome
• Significant improvement in pain corresponding to nerve
root(s) injected
○ May take 48-72 hours for corticosteroid to take full
effect
OUTCOMES
Complications
• Most feared complication(s)
○ Pneumothorax
○ Dural puncture
○ Vascular injury
– Spinal cord ischemia
SELECTED REFERENCES
1. Boezaart AP et al: Paravertebral block: cervical, thoracic, lumbar, and sacral.
Curr Opin Anaesthesiol. 22(5):637-43, 2009
2. Eckel TS et al: Epidural steroid injections and selective nerve root blocks.
Tech Vasc Interv Radiol. 12(1):11-21, 2009
3. Boswell MV et al: Interventional techniques: evidence-based practice
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