In the near future, if you have low back pain that has become chronic, you may be given a prescription for antibiotics. Most people are used to getting the usual physical therapy and medication, including pain medications, muscle relaxants, and anti-inflammatory medications. However, new research is showing a role for the usage of antibiotics for treatment of chronic low back pain.
Earlier this year, in the European Spine Journal, a group of Danish researchers published two papers which evaluate an infective cause in a sub-group of patients with chronic low back pain. In people who have chronic low back pain, certain changes (swelling from inflammation) are present in the vertebrae 46% of the time, while these changes are present in only 6% of the general population. MRI imaging can detect these changes. Several previous studies have demonstrated the presence of bacteria, especially Propionibacterium acnes, in disc nucleus tissue removed during surgery from patients who had lumbar disc herniation. Therefore, it was thought that the presence of certain bacteria in the disc, in people who had herniated discs previously, caused swelling to occur in the vertebrae that were in contact with the infected disc.
Your next question might be concerning how are these bacteria getting into the disc. Propionibacterium acnes is commonly found in skin hair follicles and in the mouth. Just brushing your teeth allows them to get into the blood stream. If you have a herniated disc in which some disc material has gotten into the spinal canal, inflammation occurs and the low oxygen environment of that material provides a great place for this particular bacteria to thrive. The bone that is next to the infected disc then becomes inflamed and the pain that many people have in the back after a disc herniation is not just the disc material compressing a nerve root, but could have resulted from this infection.
The researchers’ first paper discussed the cause of many people’s chronic low back pain while the second paper discussed the antibiotic treatment of it. In this second paper, they discussed using a common antibiotic (amoxicillin and clavulanate [Augmentin]) for 100 days of treatment in patients who had changes present on MRI scanning and had low back pain for more than 6 months after a disc herniation. In those who were in the group treated with the antibiotic, they had improvement while being treated and this improvement continued for the next year. Using a disability questionnaire in which lower scores are better, those who took the antibiotic had scores of 15 at baseline, 11 at 100 days, and 5.7 at one year while those who were comparable in disease, but only received placebo, had scores, respectively, of 15, 14, and 14. Scores regarding low back pain went from 6.7 at baseline to 3.7 at one year when the antibiotics were given, but didn’t change from the 6.3 baseline score in those who got the placebo. Regarding leg pain, those given antibiotics scored 5.3, 3.0, and 1.4, while the placebo group scored 4.0, 4.3, and 4.3. It is very clear that in a certain group of patients who have chronic low back pain, treatment with antibiotics results in a great degree of improvement.
Given that about 80% of the population will have some low back pain during their lives and that chronic low back pain is increasing (a North Carolina study showed an increased prevalence, over the fourteen years from 1992 to 2006, from 3.9% to 10.2%), this treatment could have a very major impact upon our country’s disability problem in which chronic low back pain is one of the most predominant causes. If you or someone you know might benefit from this information, please visit your physician and ask them to help you decide if antibiotic treatment might be of great benefit.