Comparison of retrolaminar paravertebral infiltration of a non steroid mixture with conventional epidural steroid infiltration in patients suffering from chronic radicular Pain a retrospective study

Introduction:Chronic radicular pain is often treated by epidural steroid infiltration (ESI). In 2014, Food and Drug Administration (FDA) issued a letter warning that ESI may result in rare but serious adverse events, including “loss of vision, stroke, paralysis, and death”. In this retrospective study, we compare retrolaminar paravertebral infiltration (PVI) of a non-steroid-mixture with ESI.

Method:  We identified 31 patients registered in the Quebec Pain Registry suffering from chronic lumbar or cervical radicular pain referred to the Centre Hospitalier de l’Université de Montréal (CHUM) pain clinic between 2009 to 2014. These patients received ultrasound-guided retrolaminar PVI with a mixture of morphine 1 mg, ketamine 10 mg, neostigmine 0.5 mg, naloxone 2 ng, and bupivacaine 10 mg. The control group, matched for gender, age, and DN4 sub-scale score at baseline, consisted of 31 patients with the same pathology; they were treated by fluoroscopic-guided ESI. Principal pathologies in both groups were disc disorders and/or foraminal stenosis. All patients received only one infiltration during the six months following the initial visit. The numerical rating scale (NRS-11) was assessed at the first visit and six months later. The BPI, PCS and SF-12 were compared in both groups. Overall satisfaction in pain relief after six months was assessed with a scale of 1 (very unsatisfied) to 6 (very satisfied).

Results: Average NRS-11 scores for the seven days preceding the first visit and after six months were compared in both groups. The same comparison was made for overal1 treatment satisfaction. There is no significant difference in the NRS-11 and in the satisfaction scores between the two groups.

Discussion/conclusion: Neither of the two methods was shown to be superior to the other in pain relief and overall treatment satisfaction after six months. Considering the possible complications and side effects of ESI, PVI with a non-steroid mixture might be considered as an alternative method. Possibly, multiple PVIs could further decrease pain. Well-designed studies are needed to evaluate this hypothesis.