Efficacy of Epidural Injection of Steroid Combined with Local Anesthetics for Low Back Pain and Lumbosacral Radiculopathy

Inflammatory response may play role in symptomatic nerve irritation that is associated herniated disc. Steroids decrease neurogenic inflamation, inhibit phospholipase A2 and produce membrane stabilization that result in pain relief. Local anesthetics are believed to break the cycle of pain that exists between local pain and a secondary muscle spasm. Epidural block with steroid combined with local anesthetics(EBSL) are recommended in patients with sign and symptoms of nerve root irritation. The purpose of this study was to asses of ESBL.

A retrospective study undertaken of 20 patients who received ESBL from May 2004 to November 2005 at the pain clinic of Mokdong Hospital Ewha Womans Medical Center. The mean age of the patients was 52, with range from 18-82 years. Nine patients was male, eleven were female. The etiologies of the pain were low back strain(3 patients), bulging disc(9 patients), degenerative disc(4 patients), lumbar stenosis(2 patients) and spondylolisthesis(2 patients). Diagnostic workouts were history, physical and neurologic examinations, and labo-rative studies including simple X-ray and magnetic resonance image. The steroid preparation usedis methylprednisolone and the use of dilute local anesthetics Is mepibacaine. The method of technique of EBSL was median approach with loss of resistance technique. The clinical responsefall into four categories, 6 months follow up after therapy. An excellent response was defined ascomplete resolution of presenting symptoms. A good response was judged to greater than 75%improvement in symptoms with full resumption of the patients life style. A fair response was defined as improvement in the patients condition, whereas a poor response indicated little or noimprovement. The total numbers of blocks were 48 in 20 patients and 2.4/per patient. The duration symptoms within one month were 8 patients and the other 12 patients over one month.

A detailed follow-up of 20 patients with EBSL showed a successful rate(good to excellent) 65%, fair 25%, and poor 10%. The effective responses of EBSL were depend on the etiologies, duration of pains and patients age. All patients of low back strain with one month duration or less have a response rate of very successful excellent. Also all patient with bulging disc who present with pain within one month have a response rate of excellent 3(60%), good 2(40%) and the patient who present with pain of over one month or more have a response rate excellent 1(25%), fair 2(50%) and poor 1(25%). All patients of degenerative disc present with pain of over one month have 50% relative success rate and good 2 patients. The response rate of two patients of spinal stenosis and two patients of spondylolisthesis present pain of long time(2-6 months) and response rate showed fair 3, poor 1, and 0% of successful rate.

EBSL can safely performed and its efficacy has been established in patients with low back strain and bulging disc. The success of this therapeutic procedure depends on attention to selected of patient etiologies and concomitant therapies. In addition, well controlled studics are needed to evaluate any effectivness of EBSL on back pain and radiculopathy.