Epidural Steroid Injections For Back and Leg Pain

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In the last several years there has been a noticeable increase in so called pain clinics that operate in a hospital setting and are frequently manned by M.D.s who are trained as Anesthesiologists.

Pain Clinics exist in the location where I practice and in the hospitals where I have privileges.

Frequently patients with back and leg pain, often referred to as sciatica, are subjected to epidural steroid injections.

These injections are given in the Clinic guided by a fluoroscopic x-ray unit referred to as an Image Intensifier. The medication, whatever the physician chooses to inject, although it almost always contains a steroid, is placed in the spinal canal outside the envelope covering the nerves which is called the dura. Therefore the injection is usually generically referred to as an epidural steroid injection, meaning outside the dura.

A large British randomized trial demonstrated that these epidural steroid injections had only an early short term benefit to patients.

This certainly has been my impression also in the patients that I have referred to a Pain Clinic for this purpose.

Usually the injections are not done as a single injection, but are given in a series. This would include 3 injections given on a weekly basis.

A large proportion of patients receiving the epidural steroid injections reported a short improvement. The benefit of the injections disappeared by the 6th week.

It was noted in the several sub groups, that is patients with acute and chronic symptoms, with and without MRI studies pre-injection, and patients with and without positive neurological findings, all did approximately the same, that is the benefit disappeared fairly rapidly.

While I do not personally perform steroid epidural injections I take care of many patients who have had them and this would be my experience almost exactly. One has to also factor in the placebo effect noting that no matter what the treatment given in a particular situation some patients will improve.

Most of us who send patients for epidural steroid injections who have symptomatic disc herniations are not feeling that the patient will experience a long term benefit.

My colleagues and I are hoping to temporarily benefit the patient and relieve symptoms while the favorable natural history of lumbar disc protrusion and sciatica symptoms run their course.

It should be noted that not all epidural steroid injections are given with the radiologic guidance of an image intensifier.

Some physicians feel that the epidural injections can be given adequately without the aid of an image intensifier, but other physicians feel that in doing this technique the target may be missed and that epidural steroid injections are ineffective because the medication was not placed in the proper area.

Radiologists have debated this problem for years feeling that inaccurate injections when image intensifier is not used might account for the broad range of outcomes ranging from 18 to 90 percent. They believe that this difference may be related in part to inaccurate anatomic deposition of medication.