cervical interlaminar epidural steroid injection

Cervical interlaminar epidural steroid injections (ILESIs) are used to inject steroids in the epidural space and around the exiting nerve roots and are one of the two main spinal epidural injections; the other cervical transforaminal epidural injections.

Indications

Typically performed in patients with radicular arm pain who are wishing to avoid surgery and/ or may not be surgical candidates.

Contraindications

Absolute
  • actively taking anti-coagulation
  • anaphylaxis to contrast medium/ injectate
  • active infection
Relative
  • unable to remain still
  • recent previous steroid injection

Procedure

Preprocedural evaluation

Relevant imaging should be reviewed and details of the patient confirmed. The patient should have an opportunity to discuss the risks and benefits and consent obtained.

Risks include:

  • infection
  • bleeding
  • allergy 
  • intrathecal injection

Driving is not advised as a local anesthetic is included in the epidural injectate.  The reasons include an inability to perform an emergency procedure and be in safe control of a vehicle.

Positioning/room set up

The patient should be comfortable and placed prone on the fluoroscopy table, with the posterior neck and thorax exposed. A pillow or specially designed brace is usually placed under the chest and a towel under the forehead making the patient more comfortable during the procedure.

Equipment
  • alcohol or iodine (or both) containing skin preparation
  • sterile gloves
  • fenestrated or chuck-drapes
  • needles e.g. 22-gauge Tuohy
  • short extension tubing
  • syringes e.g. x3 10mL, 5mL
  • isotonic contrast, e.g. 240 mg/mL iohexol
  • local anesthetic, e.g. 1% lidocaine
  • corticosteroid steroid
  • 0.9% saline
  • long-acting local anesthetic, e.g. bupivacaine
  • bandaid
Technique
  • plan the procedure using, when possible, previous CT/MRI exams
  • after patient positioning, select the needle entry and demarcate it on the skin
    • on a true AP identify the level to be approached (e.g. C6/7 or C7/T1)
    • mark the point located halfway down from the superior endplate of the inferior vertebral body (e.g. C7 when accessing C6/7) and halfway between the spinal process and the pedicle
  • skin preparation and drapes placement
  • introduce the needle and angle it towards the midline 
  • rotate the image 45-55 degrees contralaterally and then progress the needle under fluoroscopy view, ~1 mm at a time, and verify with a small amount of contrast until reaching the posterior epidural space
  • confirm the posterior epidural space with a few mL of contrast injection
  • inject the therapeutic mixture    
  • Postprocedural care

    As with other epidural injections, recovery in the department for 20-30 minutes minimum is recommended.

    Complications

    As with all epidural spinal injections, care should be taken to confirm extradural location, to avoid intradural injection with resultant adhesive arachnoiditis. A low-pressure headache can also result from dural puncture (subarachnoid tap).

    Post-procedure infection is rare.