Source: Richard Robinson, DG News
SAN DIEGO, CA -- 2000-05-04 -- Botulinum toxin injection is effective for some forms of lower back pain, according to a study presented at the 52nd Annual Meeting of the American Academy of Neurology held here May 3, 2000.
Botulinum toxin has been used in a variety of conditions marked by muscle overactivity, including dystonia and spasticity. Its muscle-weakening effects last from two to four months in most clinical conditions.
To test its efficacy for lower back pain, Bahman Jabbari, MD, and Colleagues at uniformed Services University, in Bethesda, MD, performed a double-blind, placebo-controlled trial in 28 consecutive patients diagnosed with mechanical lower back pain.
Patients received either saline or 40 Units Botox into each of five sites in the paravetebral muscles from L1-L5, unilaterally on the side of maximum discomfort. Pain and functional impairment were documented at baseline, and at three and eight weeks, by a Visual Analogue Scale and the Oswestry Low Back Pain Questionnaire (OLBPQ).
At three weeks, 11 of 14 treated patients, but only four of 14 placebo patients, showed greater than 50 percent pain relief (p=0.02). At eight weeks, this level of pain relief was achieved by nine of 14 treated patients, but only by two of 14 placebo patients (p=0.01). Functional improvement, as documented on the OLBPQ, 70 percent for treated patients vs. 20 percent for placebo patients.
"No side effects were reported by patients," Dr. Jabbari said, "which is significant, since excess weakness might have been expected to lead to gait deterioration. In fact, some treated patients reported a gait improvement."
The study was titled, "Botulinum toxin A and mechanical low back pain."
Note on units: The difference between unit potency among available brands is a significant issue in BTX treatment. The brand name should always be given when Units are discussed.
Leslie Foster, Larry Clapp, Marleigh Erickson, Bahman Jabbari. Washington, DC; Tacoma, WA; Washington, DC.
52nd Annual Meeting of the American Academy of Neurology, San Diego, USA, May 2000.
OBJECTIVE: To investigate the effectiveness of botulinum toxin A (Botox) in chronic,mechanical low back pain and associated functional impairment
BACKGROUND: Effectiveness of botulinum toxin A, against pain associated with cervical and limb dystonias, spasticity & muscle cramps has been established in several double blind studies. A double blind study investigating the effect of Botox on mechanical low back pain has not been published previously.
DESIGN/METHODS: We have studies twenty eight, consecutive patients with mechanical low back pain,15 females/13 males with a mean age of 46 years ( range 18-72). The patients baseline level of pain and the degree of functional impairment were documented by the visual analogue scale (VAS) and the Oswestry slow back pain questionnaire ( OLBPQ). Using a randomized,double blind design, we injected half of the patients with 200 units of Botox in the paravertebral muscles. Botox was injected at five lumbar levels (L1-L5), 40units/site, unilaterally and on the side of maximum discomfort. The other half of the group, received normal saline(NS) in a similar fashion. VAS and OLBPQ were repeated at 3 and 8 weeks.
RESULTS: At three weeks, 11 of 14 patients( 78%) who received Botox showed significant(more than 50%)pain relief, versus 4 of 14 (28%) in the NS group( P 0.02). At eight weeks, 9 of 14 patients in the Botox group and 2 of 14 (14%) patients in the NS group disclosed significant relief (P 0.01). Repeat OLBPQ depicted 70% functional improvement in Botox group versus 20% improvement in the NS group. There were no side effects.
CONCLUSIONS: Paravertebral injection of botulinum toxin A in patients with chronic low back pain is safe and results in significant improvement of pain and function at three and eight weeks.