Caudal Epidural Steroid Injection

EQUIPMENT

Syringe	Needle	Dexamethasone	Further injectate	Total Volume
20mL	21G 40mm 25G 50mm	15mg NB: Must be dexamethasone	No lidocaine Add normal saline.	L5: 10mL L3: 15mL Upper lumbar: 20mL

Technique

• Position: prone with heels rotated laterally, and a cushion pillow is used as an iliac wedge.
• Identify sacral cornua at base of imaginary triange with thumb (needle will go between cornua)
• Obtain a transverse image for the sacral hiatus and dorsal sacrococcygeal ligament between the bilateral sacral cornua,
• Obtain a longitudinal view and advance needle at a 45 degree angle.
• Terminate needle advancement right after piercing the sacrococcygeal ligament. This is to avoid injection into the venous plexus and intrathecal injection in those with unusually low terminating dural sacs.
• Aspirate to ensure needle not penetrated thecal sac or blood vessel. If aspirate CSF then abort procedure and retry in one week.

Indications

Good evidence for radicular leg pain due to lumbar disc herniation. 72.5% complete or partial pain relief at 12 weeks in those with symptom duration of 4-52 weeks. Fair evidence for axial pain and spinal stenosis and post surgery syndrome

Risks

Infection, subcutaneous injection, spinal cord infarction, Radiculopathy <1:2,000 paraplegia 1:50,000, allergic reaction, intravascular injection (minimal risks with dexamethasone due to small particulate size), dural puncture with headache, PE, ADR from steroids, increased back pain (3.1%)

Aftercare

Advised to keep active within pain limits, and is reassessed about 10 days later. Steroid remains in situ for about 2 weeks. Up to 3-4 injections may be performed before declaring the therapy a failure. Max 0.6mg/kg or 40mg dexamethasone per year.