Epidural Corticosteroid Injections and Low Back Pain

General Principles
Although injections may be helpful in confirming a diagnosis, they should be used primarily after a specific presumptive diagnosis has been established. Injections should not be used in isolation, but rather in conjunction with a program stressing muscle flexibility, strengthening, and functional restoration. Proper follow-up after injections to assess the patient's treatment response and ability to progress in the rehabilitation program is essential. A limited number of injections can be tried to reduce pain, but careful monitoring of the response is required prior to a second or third injection.

These injections are an adjunct treatment, which facilitates participation in an active exercise program and may assist in avoiding the need for surgical intervention. All physiatrists who perform injections should be aware of the indications, contraindications, and complications of therapeutic injections, and fully inform patients of the potential risks.

Epidural Corticosteroid Injections
The rationale for the use of epidural corticosteroid injection has improved with the evidence of an inflammatory basis for radicular pain from disc herniation. Epidural steroids have been shown to be effective in pain reduction in patients with radicular pain, although controlled prospective trials are lacking. The efficacy is increased if used in the first weeks following onset.

The goal of these injections is to facilitate an active exercise program and to progress patients through the pain and inflammation stage of recovery as quickly as possible. As with all injections, it should be part of a comprehensive treatment plan involving active exercise. To ensure proper needle placement of corticosteroids, fluoroscopic guidance is recommended.

When injecting in a blind fashion, medication might often be placed into the subarachnoid space, subjecting the patient to the adverse effects of intrathecally injected steroid and anesthetic. Some patients may require more than one injection. Repeat injections should be based on pre-treatment goals and the therapeutic response following the injection.

It is not necessary for most patients to undergo a set number or "series" of injections. If minimal to no improvement is found after two injections, then further similar injections are not warranted. The more recent use of a transforaminal approach allows the medication to be delivered in a more targeted fashion to the more ventral aspect of the spinal canal at the level of the presumed site of pathology.

All patients should be followed after injections (10-14 days after) to assess therapeutic response. Epidural injections and intradiscal injections have been used in the treatment of nonradicular degenerative disc disease with limited success.

In addition, epidural steroids have been used in patients with neurogenic claudication from spinal stenosis with mixed results. A limited number of injections can be tried in these patients to reduce pain thought to be at least in part mediated by inflammation. All physicians who perform injections should be aware of contraindications and complications of epidural injections, and fully inform patients of the potential risks.