Back Pain Can Be a Real Pain in the Backside
Back pain sometimes hurts just in the low back. But it can also be a pain in the rear--and a pain in the leg. Pain from the back that shoots into the buttock or leg is called radicular pain.

Foraminal stenosis and herniated discs are two common causes of radicular back pain. In foraminal stenosis, the spine narrows and may pinch nerves as they leave the spinal cord. A herniated or bulging disc can push on the nerves leaving the spinal cord. Pressure on nerves can cause a lot of pain and weakness in the back and down the legs along the path of the nerve. Radicular back pain can be so disabling that patients may need surgery to stop the pain.

Doctors often treat radicular back pain with epidural injections of steroids, although the effectiveness of this treatment is controversial. Another method for getting steroids to the inflamed nerve is called a selective nerve-root injection. Doctors use a special kind of X-ray called a fluoroscope to guide a needle directly to the painful spinal nerve. This procedure gets more medication to the painful spot.

These researchers wanted to compare whether nerve-root injections using numbing medicine alone or in combination with steroids actually lessened radicular back pain. They were also interested to see whether patients got enough relief that they no longer wanted or needed back surgery.

Researchers selected 55 patients who had requested back surgery to relieve their pain. They were divided into two groups. Twenty-seven patients received bupivacaine, a long-acting numbing medicine. The other 28 patients received bupivicaine plus a steroid. The researchers considered the treatment a failure if the patient went ahead with surgery. From the group who received bupivicaine alone, 18 patients ended up going through with surgery. But only eight who'd gotten bupivicaine in addition to the steroid needed surgery.

The math is pretty straightforward. Out of the 55 total patients, 29 avoided surgery after being treated with nerve-root injections. And even though bupivicaine alone was helpful, the number of people helped by getting the additional steroid was significant.

This study showed no difference in pain control between the patients with spinal stenosis and patients with a herniated disc. However, the researchers questioned whether this would be the case over time. It's been shown that herniated discs can fully recover without any treatment, while foraminal stenosis typically worsens with time. This study followed patients from 15 to 28 months. If patients with a herniated disc avoided back pain in this time frame, it is unlikely that they would need surgery in the long run. The authors conclude that treatments like nerve-root injection could be just what the doctor ordered in helping more people avoid back surgery.
K. Daniel Riew, MD, et al. The Effect of Nerve-Root Injections on the Need for Operative Treatment of Lumbar Radicular Pain. In The Journal of Bone and Joint Surgery. November 2000. Vol.82-A. No 11. Pp 1589-1593.