Ebook The handbook of C-ARM fluoroscopy guided spinal injections: Part 2

(BQ) Part 2 book The handbook of C-ARM fluoroscopy guided spinal injections has contents: Fluoroscopic images of the cervical spine, cervical injections, fluoroscopic images of the sacrum and pelvis, pelvic and sacral injections, sympathetic blocks.

Positioning the Patient

Cervical spinal injections can be done in either the supine (Figure 7.1A), prone (Figure 7.1B), or lateral positions (Figure 7.1C).

Positioning the C-Arm

The C-arm can be positioned in many ways for cervical spinal injections (Figure 7.2) For example, the C-arm can be positioned from the patient’s side, as when performing lumbar procedures (Figure 7.2A) The C-arm can also be positioned from behind the patient’s head (Figure 7.2B) The C-arm can be positioned to get a lateral view of the cervical spine as seen in Figure 7.2C and Figure 7.2D.

A/P (P/A) View and Lateral View of the Cervical Spine

Images of both the anterior–posterior (A/P) view in the prone position, the posterior–anterior (P/A) view in the supine position and the lateral view of the cervical spine, look quite different from images of the A/P and lateral view of the lumbar spine (Figure 7.3) This is due to the unique shapes of the cervical vertebrae.

FIGURE 7.3

The cervical and the lumbar spine (A) P/A view of the cervical spine (B) A/P view of the lumbar spine (C) Lateral view

of the cervical spine (D) Lateral view of the lumbar spine

DC

Mandible

Comparison of Cervical Vertebrae and Lumbar Vertebrae

Like a lumbar vertebra (Figure 7.4B), a cervical vertebra (Figure 7.4A) consists of the vertebral body, two transverse processes, two pedicles, lamina, two superior articular processes, two inferior articular processes, and a spinous process However, the cervical vertebra differs from the lumbar vertebra Their differences are summarized in Table 7.1 Figure 7.5 is a P/A view image of the cervical spine.

FIGURE 7.4

(A) Cervical vertebra (superior view) (B) Lumbar vertebra (superior view) (C) Lateral view of the cervical spine from C4

to C7 (D) Lateral view of the lumbar vertebra

TABLE 7.1 Comparison of Cervical Vertebrae and Lumbar Vertebrae

Cervical Vertebra Lumbar Vertebra

Transverse process Quite small

Connects to lateral surface of vertebral bodyAnterior to the pedicle

Has transverse foramenAnterior to the superior articular process

LargeConnects to posterior surface of vertebral bodyPosterior to the pedicle

Lateral to the superior articular process

Connects to posterior surface of transverse process

LongConnects to posterior surface of lumbar vertebral body

Spinous process Varies in length

Ends in two tips (called bifid tips)

LongEnds in only one tipSuperior articular

process

Inferior articular

process

Connects to pedicle only

Articular pillar connects the superior and inferior articular processes

Connects to pedicle and transverse process

Pars interarticularis (part of lamina) connects to superior and inferior articular processes

B

C

DA

Lateral and Oblique Views of the Cervical Spine

Figure 7.6 is a lateral fluoroscopic image of the cervical spine We usually rotate the fluoroscopic image horizontally if the patient is in a supine position (Figure 7.7).

FIGURE 7.7

Fluoroscopic image of the lateral view of the cervical spine (rotation of fluoroscopic image in Figure 7.6) (1) Spinousprocess, (2) articular pillar, (3) superior articular process, (4) inferior articular process, (5) vertebral body, (6) transverseprocess with transverse image of the foramen

5Mandible

1

2

6

In true lateral images of the cervical spine (Figure 7.8), the vertebral body is squared, the articular pillar is a trapezoid shape, the facet joint space is open, the transverse process with transverse foramen cover the posterior–superior portion of the vertebral body, and the spinous process has sharp superior–posterior and inferior margins

FIGURE 7.8

Lateral images of cervical spine

Vertebral body Transverse process with transverse foramen Articular pillar Spinous process

A trapezoid

shape of

Articular pillar

Spinous process has sharp margins

Transverse processes with transverse foramina cover posterior–superior

portion of vertebral body

Vertebral body is squared off

Facet space is open Mandible

Figure 7.9 illustrates the comparison between the true lateral view and the false lateral view

of the cervical spine images The left column illustrates true lateral view images The right column illustrates the false lateral images.

It is very difficult to identify intervertebral foramina on the lateral image of the cervical spine compared with the lateral image of the lumbar spine (Figure 7.10) This is because the cervical transverse processes complex opacifies the image of intervertebral foramen However, if we view the cervical spine obliquely and inferiorly (Figure 7.11), we can visualize the intervertebral foramina easily

FIGURE 7.11

(A) Photo of inferior and oblique views of the cervical spine (B) Photo of the lateral view of cervical spine

A

B

A unique oblique image of the cervical spine (Figure 7.12) can be obtained by tilting the C-arm

to the injecting side about 45˚ and rotating caudally about 20 to 30˚ (Figure 7.13).

Cervical Intervetrebral Foramina and the Cervical Spinal Nerve Roots

There are eight cervical spinal nerve roots and only seven cervical vertebrae There is no tebral foramen between C1 and C2 The first visualized cervical intervertebral foramen is between C2 and C3 The C3 spinal nerve root travels via this foramen (Figure 7.14) The vertebral artery goes via the transverse foramina, usually from the C6 foramen to the C1 foramen into the skull (Figure 7.15A and Figure 7.16A) The possible locations of the vertebral artery are demonstrated on the laterally and obliquely viewed fluoroscopic images of the cervical spine (Figure 7.15B and Figure 7.16B).

interver-FIGURE 7.14

Method for counting intervertebral foramina and cervical spinal nerve roots

There is no foramen between C1 and C2

Mandible

The foramen between C2 and C3

Vertebral arteryA

Mandible

Vertebral arteryB

Bontrager, K.L and Anthony, B.T., Eds., Textbook of Radiographic Positioning and Related Anatomy, 2nd ed.,

C.V Mosby Company, St Louis, MO, 1990

Brown, D.L., Ed., Atlas of Regional Anesthesia, 2nd ed., W.B Saunders, Philadelphia, 1999.

Clemente, G.D., Ed., Gray’s Anatomy, 13th ed., Lea & Febiger, Philadelphia, 1984.

Fenton, D.S and Czervionke, L.F., Eds., Image-Guided Spine Intervention, W.B Saunders, Philadelphia, 2003 Netter, F.H., Ed., Atlas of Human Anatomy, Ciba Geigy Corporation, 1989.

Waldman, S.D., Ed., Atlas of Interventional Pain Management, 2nd ed., W.B Saunders, Philadelphia, 2004.

Chapter

8

Cervical Injections

Cervical Injections 171

In this chapter, we will discuss injections around the cervical spine for the relief of pain due to headaches, neck pain, shoulder pain, and arm and hand pain We will first begin with cervical facet injections, both intra-articular and medial branch injections and radiofrequency denervation, and

we will then proceed to cervical epidural and nerve root injections Both interlaminar and aminal epidural steroid injections will be discussed.

transfor-The pain physician should be very familiar with lumbar injections prior to attempting any injections in the neck Familiarity with airway management is also recommended for physicians who perform cervical spinal injections.

Preparation for the Performance of Cervical Injections

Patient preparation: We advise the patients to have no solid foods for a minimum of 6 h,

particularly prior to cervical injections We recommend that the patients have another individual available to transport them home following the procedure Sterile preparation and drape are required; preparation above and below the hairline may be required, particularly for the upper cervical injections Monitor the patient’s heart rate, blood pressure, and oxygen saturation The American Society of Regional Anesthesia and Pain Medicine (ASRA) guidelines report no evidence of additional risk for patients taking nonsteroidal anti-inflammatory drugs (NSAIDs) who received spinal or epidural analgesia.1However, when performing cervical transforaminal injections, it is the author’s practice, as a precaution, to ask the patients not to take aspirin for 7 to 10 d prior to the procedure and not to take NSAIDs (with the exception of COX-2 inhibitors) the day of the procedure.

Equipment/Materials:

• A 22- or 25-gauge 3½ in spinal needle, with or without a distal curved tip in the direction of thebevel, is used for most cervical procedures performed in the prone position A 25-gauge, 2 in spinalneedle is adequate for the vast majority of cervical foraminal and facet injections that are performedwith the patient in the supine position It is very rare, even in obese patients, to require a 3½ in.spinal needle for cervical transforaminal injections

• Intravenous (IV) access for all cervical transforaminal injections as a safety precaution in the event

of intravascular injection

• Oxygen delivered at low flows via nasal cannula is suggested

• Water-soluble nonionic dye

• Local anesthetic (e.g., 0.25 to 0.5% bupivacaine or 2% lidocaine) and steroid for a total of 1 ml orless of injectate Note that the local anesthetic and steroid may be injected together as a combinedsolution or separately

• We recommend using the least particulate steroid available for transforaminal epidural steroid orselective nerve root injections Steroids are not necessary for medial branch injections

• A syringe (or syringes) for injecting the local anesthestic and steroid A 3 ml or smaller is mended; a 10 ml syringe is too large and will generate too much pressure with aspiration and riskinadvertent vascular injection

recom-• Connection tubing to allow for contrast injection without fluoroscopy exposure to the hands Thisalso facilitates an immobile needle

• Lidocaine (0.5 to 2%) and a 25- to 27-gauge needle for local infiltration We do not recommend theuse of needles greater than 1 in for skin infiltration for cervical procedures, particularly in thinpatients We recommend very superficial, subcutaneous injections of local anesthetic to avoid intra-vascular or brachial plexus injections

Sedation: Light sedation is recommended, e.g., with midazolam 1 to 2 mg intravenously

Cervical Facet Injections

Headaches and pain felt in the neck, shoulders, and upper back may originate in the upper, middle, and lower cervical facets, respectively.2,3Cervicogenic headaches differ from vascular headaches both in their symptoms and in the origination of cervicogenic headache from the posterior superior neck These headaches may also be reproduced by palpation of the painful facet joint, with lateral neck movement, and particularly with neck extension Cervicogenic facet and radicular pain are similar in character when originally from the upper cervical levels (C1–C4) The C2/C3 joint was reported to be a source of headaches following whiplash injury Excellent response has been reported for relief of these headaches from lesions of the third occipital nerve, which innervates the C2/C3 facet joint.4Below C4, cervical facet pain radiates to the shoulder and upper back; while cervical radiculopathy involving the C5 root and below involves the shoulder then radiates distally to the arm (Figure 8.1).

FIGURE 8.1

The cervical spine, viewed from the lateral approach The needles indicate the target areas for both medial branch andintraarticular facet injections on the left side

C1(atlas)

C2(axis)

C7

T1

Intra-Articular Facet Injections

C1/C2 Joint Injection

The C1/C2 or atlantoaxial (AA) joint (Figure 8.2A) receives innervation from the C2 nerve root Pain, generally posterior headaches, that comes from the C1/C2 joint is generally localized to the suboccipital region and may be exacerbated with neck rotation Pain coming from the upper cervical facets is more often manifested as headache rather than neck pain.5The C-arm should be adjusted

in order to obtain the clearest view into the joint The angulation of the C1/C2 joint is not as caudal

as it is in the lower cervical facets The vertebral artery is just lateral to the C1/C2 joint; thus the needle should stay medial to the lateral border of the C1/C2 joint at all times If the needle enters medial to the junction of the lateral one third of the joint, the likelihood of an intrathecal injection increases (Figure 8.2B).

Indications:

1 Neck pain with associated posterior headache

2 Upper neck pain exacerbated by neck movement

(A)

(B)

FIGURE 8.2

(A) Photograph of a spine model of the C1/C2 joint (B) The spine with the C1/C2 joint marked

Atlantoaxial (AA) joint

Cervical Injections 175

Contraindications:

1 Patient refusal

2 Systemic anticoagulation or coagulopathy

3 Systemic or localized infection at the site

4 Unstable cervical spine

Patient position: The patient is placed in the prone position; a pillow may be placed under

the chest to allow for slight neck flexion (Figure 8.3).

3 We recommend saving copies of the A/P and lateral views showing the location of the needle tipbefore and after the injection of contrast into the joint

Procedure:

1 The patient’s posterior occipital region is prepped in a sterile fashion above and below the hairlineand then draped

2 The C-arm is positioned as described above

3 A 22- or 25-gauge, 3½ in spinal needle is used A slight curved tip often makes the needle easier

to steer and allows for “bevel control.”

4 It is easier to visualize the AA (C1/C2) joint if the patient’s mouth is open (Figure 8.4A and Figure 8.4B)

5 The needle is advanced from the caudal aspect of the AA joint and enters the joint at the junction

of the lateral one third and medial two thirds of the joint in the A/P view

6 The needle depth is ascertained in the lateral view, and the needle tip position within the AA joint

is determined in the A/P view

FIGURE 8.3

The patient position for C1/C2 intraarticular injection

A pillow under the chest

7 Advancing in the A/P view increases the likelihood that the needle will stay in the correct locationwithin the joint space.

8 Verify the needle depth periodically with lateral views (Figure 8.5)

9 After negative aspiration, <0.5 ml of nonionic contrast dye into the joint is recommended to verifythe correct needle position (Figure 8.6)

10 The joint space is entered inferiorly and then walked in The target is the junction between the lateralone third and medial two thirds of the joint space A small volume of local anesthetic and steroid isinjected into the joint space after negative aspiration

11 After negative aspiration, the combination of local anesthetic and steroid is then injected carefullyinto the joint

FIGURE 8.6

Examples of A/P views of dye within the left C1/C2 joint space

1 Injection into the vertebral artery, venous plexus, or cerebrospinal fluid (CSF) of air, local anesthetic,

or steroid

2 Injection into the foramen magnum or spinal cord

3 Laceration of the vertebral artery

4 Cerebellar hemorrhage or infarction

C2/C3 to C6/C7 Intra-Articular Joint Injections

Pain from the C2/C3 to C4/C5 facets is felt in the neck and upper shoulders.6,7Below this level, the pain spreads distally down the upper back and scapulae The symptoms are increased with neck extension and lateral bending and may be reproduced with palpation of the facet joints, particularly when palpated from a slightly lateral direction

Contraindications:

1 Patient refusal

2 Systemic anticoagulation or coagulopathy

3 Systemic or localized infection at the site

4 Unstable cervical spine

Patient position: Intra-articular injections of the C2/C3 to C6/C7 facet joints may be performed

in the prone, lateral, or supine positions In the supine and lateral positions, the lateral view is used;

in the prone position, the A/P view is used

C-arm position:

1 From the supine position:

a The C-arm may either be perpendicular to the patient’s head or in line with the patient when it

is positioned behind the patient’s head

b It is important to keep the patient’s head looking up toward the ceiling to keep the head in neutralposition

c Tilt the C-arm to get a lateral view showing clear joint lines without an overlapping shadow fromthe contralateral joint (Figure 8.7)

d It is important to get a true lateral view with even joint space margins when performing theseinjections (see Chapter 7, Figure 7.9), otherwise, the needle may venture posteriorly and medially,resulting in intrathecal injection or cord injury The needle tip position should be verified in boththe A/P and lateral views, even if it “feels” as though it is in the joint.

2 From the prone position:

a The prone position has advantages in the performance of bilateral intra-articular cervical facetinjections When bilateral injections are performed in the supine position, the contralateral needlemay obscure visualization once contrast is injected In the prone position, there is no overlappingimage from the contralateral side

b The cervical facets are slanted in a slightly caudad direction

c The C-arm is rotated forward so that the image intensifier is toward the feet, and the joint spaceappears to be more open (Figure 8.8)

d The needle entry is from slightly caudal to the cervical facet joint

e It may sometimes be necessary to slightly rotate the patient’s neck to the contralateral side inorder to better visualize the joint space

f The needle entry is at the lateral one third of the joint

g Stop advancing the needle once change in resistance is felt and the joint space is entered

h In the prone position, the A/P view is used for the needle approach to the joint, and the lateralview is used to check the needle depth (Figure 8.12)

Procedure:

1 From the supine position:

a The lateral fluoroscopic view is used for needle entry

b Needle entry is at the inferior to middle aspect of the joint space and is advanced into theradiolucent joint space, keeping the needle tip over the joint space at all times (Figure 8.9A)

c Once the change in resistance is felt and the joint space is entered, stop advancing the needle

d The needle tip position is verified in both the A/P and lateral views, even if it “feels” as though

it is in the joint (Figure 8.9B)

e A small amount of nonionic dye injected into the joint space verifies the correct position of theneedle (Figure 8.10)

f If the capsule is disrupted, there may be epidural spread (Figure 8.11).

g For injection, <1 ml of a solution of local anesthetic and steroid is recommended.

h A small amount of nonionic contrast injected into the joint space verifies the position of theneedle

i If the capsule is disrupted, there may be epidural spread

j A solution of local anesthetic and steroid, <1 ml, is injected

Cervical Medial Branch Injections

Cervical medial branch injections may be performed in either the prone or supine position, utilizing A/P, lateral, or oblique approaches.8The cervical facets may be anesthetized with a local anesthetic blockade of the medial branches of the dorsal rami of the spinal nerves that supply each joint The typical location of the medial branches is in the center of the trapezoid formed by the lateral aspect

of the facet This is most often seen at the C4 and the C5 medial branches that innervate the C4/C5 facet joint (Figure 8.13) Medial branch injections are performed as a diagnostic tool prior to the performance of radiofrequency denervations of those nerves The cervical facet joint is innervated

by the medial branches of the nerves above and below that joint For example, the C4/C5 facet joint is innervated by the medial branches of the C4 and C5 dorsal rami of the C4 and C5 spinal nerves Thus, in order to anesthetize the C4/C5 facet joint, two injections must be performed When using the oblique approach for medial branch injections or denervations, the needle entry is slightly below (posterior to) the foramen in the oblique view The target site is at the base of the superior articular process in the oblique view and in the center of the waist of the vertebra in the posterior– anterior (P/A) view In the lateral view, it is in the center of the image that has the appearance of

a trapezoid In the lateral view of the lower cervical facets, the medial branches have been described

to lie in the superior aspect of the waist of that trapezoid.

FIGURE 8.12

Intraarticular injection performed in a patient in the prone position, with dye spread along the joint space

branches

1 Patient refusal

2 Systemic anticoagulation or coagulopathy

3 Systemic or localized infection at the site

4 Unstable cervical spine

Patient position: This procedure may be performed with the patient in the supine, lateral

decubitus, or prone position The supine position is commonly used for most of the cervical procedures that we perform.

C-arm position: A more detailed description of C-arm positioning is found in Chapter 7 In all of the

injections described in this book, it is imperative that the image on the screen is a clear representation

of the target area Refer to Chapter 7 for details on how to get a properly aligned fluoroscopic image ofthe cervical spine in the lateral, P/A and A/P, and oblique views

1 This procedure is easier to perform with the C-arm at the head of the patient and the patient in thesupine position Unless otherwise specified, all of the descriptions below will refer to the patient inthe supine position

(B)

FIGURE 8.13 (continued)

(B) Diagram of the target point for cervical medial branches in the center of the trapezoid

Cervical medial branch is located in the center of the trapezoid

2 The cervical medial branches may be approached from the lateral, prone, or oblique view.

3 Lateral approach:

a The patient is in the supine position with the head facing the ceiling (Figure 8.7A)

b Square off the cervical facet joints with the C-arm in the lateral view

4 Oblique approach (Figure 8.14):

a Square off the cervical end plates in the A/P view by moving the image intensifier approximately20˚ toward the feet

b Then, move the C-arm between 45 and 50˚ until the contralateral transverse foramen are justbelow the superior border of the vertebral bodies, and the ipsilateral transverse foramen appear

as dark ovals on the posterior aspect of the spine This view is slightly different from the obliqueview used for cervical transforaminal injections In this view, the contralateral transverse foraminaare more posterior to the border of the vertebral bodies than is seen in the view for the cervicaltransforaminal injections.9

c The cervical foramen should be easily visualized in this view

FIGURE 8.14

Diagram of the oblique C-arm position for cervical medial branch injections

5 Prone approach:

a The head may be in the neutral position, facing down; the neck should not be extended

b The C-arm is rotated forward until the best view of the joints is seen

c The posterior approach must be used to access the C8 medial branch, and we recommend it forC7 medial branch radiofrequency denervations as well

Procedure:

1 Lateral approach (Figure 8.7A, Figure 8.13, Figure 8.15)):

a The needle entry is at the center of the trapezoid seen in the lateral view This is best seen withthe C4 and C5 levels

b The needle depth is checked in the A/P view, and the location of the needle tip with respect tothe facet is checked in the lateral view

c In the A/P view, the needle is seen in the lateral concavity of the cervical facetal column Theneedle should not be medial to this lateral border

d The medial branches of the C3, C6, and C7 dorsal rami lie more superiorly along the trapezoid

e The needle tip should be advanced on top of bone (the trapezoid) to avoid entry into the epidural

or intrathecal spaces

2 Oblique approach:

a Needle entry is slightly below the foramen and angled anteriorly

b The needle tip should be advanced on top of bone as much as possible Posterior placement ofthe needle during advancement increases the possibility of a medial (epidural or intrathecal)needle position

c The needle is advanced until it hits bone

d The needle position may be checked in the lateral view

e The needle position is also verified in the A/P view to ensure that it is lateral to the cervical facetshadow (Figure 8.16)

FIGURE 8.15

Lateral view of a cervical medial branch injection