Epidural Clonidine for Lumbosacral Radiculopathy

Pilot Study of Transforaminal Epidural Injection of Clonidine for the Treatment of Acute Lumbosacral Radiculopathy

This was a randomized, blinded study of transforaminal epidural injection of clonidine versus a similar injection of corticosteroid for acute lumbosacral radiculopathy. The hypothesis was that clonidine will be as effective as steroid for this condition.

Patients with approximately 3 months of low back pain and leg pain due to intervertebral disc herniation were randomized to transforaminal epidural injections of 2% lidocaine and either clonidine (200 or 400 micrograms) or triamcinolone (40 mg) (corticosteroid). Patients received one to three injections administered at about 2 weeks apart. Patients, investigators, and study coordinators were blinded to the treatment. The primary outcome was an 11-point Pain Intensity Numerical Rating Scale at 1 month. The hypothesis was that clonidine will be as effective as steroid for this condition.

Inclusion Criteria:

• Residents 18 years or older of Olmsted or contiguous counties and identified as having an acute unilateral radicular syndrome of less than 3 months duration (leg pain>back, discogenic cause, one or more of the following:

  • Positive Straight Leg Raise (SLR) test
  • Myotomal weakness
  • Dermatomal sensory loss) and with concordant
  • Confirmatory findings on recent MRI or CT myelogram

Exclusion Criteria:

• History of recent spinal trauma
• Cauda equina syndrome (This is a serious neurologic condition in which there is acute loss of function of the lumbar plexus, neurologic elements of the spinal canal below the termination of the spinal cord.)
• Progressive neurological deficit
• Motor deficit
• Pathological or infectious etiology
• Involvement in workers' compensation claim
• History of adverse reaction to corticosteroids, local anesthetic or clonidine
• History of one or more corticosteroid injection(s) (equivalent to 40 mg of triamcinolone acetate) in the preceding 4 months
• Pregnant
• Severe medical disease