Researchers at the John Hunter Hospital and the Newcastle Bone and Joint Institute, both in Australia, recently finished a study on the effectiveness of transforaminal steroid injections. The study tested the injections as a viable treatment for lumbar radicular pain (sciatica) caused by a herniated disc before surgery is considered.
Injections are typically performed after physical therapy, chiropractic, and oral medications are ineffective for relieving the patient’s pain. The injections are intended to reduce or relieve pain to allow further time for the body to heal so the patient can delay surgery or avoid it altogether.
Recent studies have questioned the effectiveness of these injections, questioning the need for steroids to be used or the best location for such injections. A transforaminal steroid injection is an injection of glucocorticoid (steroid hormone) into the foramen of the spine. The steroid injected is intended to reduce inflammation around the herniated disc, temporarily relieving pain in the area while giving the body time to heal. Other studies have found evidence that the steroids are not necessary if the pain relief mechanism was not from the steroids reducing inflammation, but from the liquid irrigating the area or from the local anesthetic. Other studies have suggested the steroid could be injected into surrounding muscle tissue with similar results or that the injections do not outperform placebo treatment.
In this study, the researchers divided patients into five groups to address each reasonable variation:
- Transforaminal Injection of Steroids – Testing efficacy of procedure
- Transforaminal Injection of Anesthetic – Testing if the local anesthetic causes pain relief
- Transforaminal Injection of Saline – Testing if irrigating the area causes pain relief
- Intramuscular Injection of Steroids – Testing if location injected changes efficacy
- Intramuscular Injection of Saline – Placebo
The researchers considered a treatment to be a positive result if at least 50 percent of the patient's pain was reduced one month after the injection procedure. In the group treated with a transforaminal steroid injection, 54 percent of patients had positive results. The placebo group had 13 percent of the patients with a positive result. The transforaminal saline injection and the intramuscular steroid groups had similar efficacy with 19 and 21 percent, respectively. The only group with less positive results than the placebo group was the transforminal injection of anesthetic, with only 7 percent of patients showing positive results.
The study showed that transforaminal steroid injections, which use a steroid hormone injected into the foramen of the spine, provide greater pain relief than the other injection variations tested. These findings support the use of steroids over other liquids and support the foramen as the injection site over the surrounding muscle tissue.