Spinal interventional procedures

Back pain is a common condition that is often difficult to treat. Lumbar degenerative facet joints, lumbar disc disease and sacroiliac joint pain account for nearly 70% of cases of lower back pain.

Unfortunately, as the incidence of degenerative changes in the spine is so high (e.g. disc abnormalities are found in 25% of individuals below the age of 60, and over 50% in those over the age of 60), it is sometimes difficult to confidently identify the cause of pain, without careful correlation with clinical findings and potentially diagnostic injections. The other role of spinal injections is to treat non-operative back pain.

Procedures include:

• sacroiliac joint injection
• facet joint injection
• spinal epidural injection
  • transforaminal epidural injection
  • interlaminar epidural injection
  • caudal epidural injection (via the sacral foramen)
• transforaminal nerve root block
• epidural blood patch
• vertebroplasty

All these procedures require precise needle tip position and therefore are performed with imaging guidance, either fluoroscopy or CT.

General contraindications

The following are general contraindications to elective spinal interventionalinternational procedures:

• active sepsis
• known allergy to local anaesthetic/steroids/contrast agents
• pregnancy
• bleeding tendencies
• anticoagulationanti coagulation
• particulate steroids should be avoided in cervical spine epidural injections

Complications

• bleeding with possible epidural haematoma requiring evacuation or resulting in weakness and other sequelae
• infection with possible epidural abscess requiring evacuation or resulting in weakness and other sequelae
• intraarterial injection can results in cord or brain stem infarction
• neural compression or ischaemia
• decrease in diabetic control
• gastritis (especially if the patient is on concurrent NSAID)
• intrathecal injection of steroids may result in arachnoiditis; this is mainly due to excipients such as polyethylene glycol
• benzyl alcohol has caused necrosis and apoptosis of retinal pigment epithelial cells
• repeated steroid injections may result in epidural lipomatosis

Equipment

As in everything, there are many variations on this theme:

• spinal needle for deep injection (typically a 22G or 25G)
• skin needle for local anaesthetic
• local anaesthetic to skin and superficial structures, e.g. lignocaine 1% or 2%
• therapeutic injection
  • bupivacaine 0.2% to 0.5%, 1-2 mL
  • steroid approved for epidural injection