Predictive factors for treatment success of transforaminal epidural steroid injection in lumbosacral disc herniation induced chronic pain.

Lumbosacral disc herniation is a common cause of chronic low back pain in

adults. Disc herniation induced pain is triggered by mechanical compression on

the dorsal root or ganglion of the herniated disc material or inflammation induced

by chemokines and enzymes in the disc(1). This pain is usually characterized by

pain arising in the back with or without radiation to lower limb in distribution in

one or more nerves.

Transforaminal epidural steroid injection (TFESI) involves instillation of

corticosteroids around the inflamed nerve root along with low concentration

solution of local anaesthetic . Fluoroscopy guided injection is given through the

intervertebral foramen into the ventral epidural space close to the pathological

site. This helps alleviate the pain by anti-inflammatory and neural membrane

stabilization effects of steroids, increase blood flow to ischemic spinal root

through local anaesthetic agent and removal of cytokines by washout effect of

injection(2,3) . This technique for treatment of lumbosacral radiculopathy is a

cost effective procedure in the majority of cases as compared to other operative

interventions. Complications associated with surgery such as recurrence,

cerebrospinal fluid leakage , haematoma and infections can be avoided . Despite

the established efficacy of TFESI for disc herniation related pain, successful

outcomes may not be obtained in all patients. There could be several variable

factors which might have an impact on treatment outcome in the immediate post

procedure period and later on. These factors could be patient related factors,

clinical or radiological findings. With the need to reduce low value healthcare it

would be helpful to be able to better identify patients who have a reasonable

chance of benefiting from ESI. Therefore this study aims to identify predictive factors for successful treatment outcome 3 months after TFESI in patients with

lumbosacral disc herniation induced pain.