Conditions: Lower Back Pain
Keywords: Back Pain Muscle
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 43
Healthy volunteers: no

Brief summary:
The scientific aim of this study is to investigate the efficacy of abobotulinumtoxinA (Dysport - Ipsen Pharmaceuticals) in chronic low back pain.

The investigators hypothesis is that injection of Dysport brand of botulinum toxin type A into erector spinae muscles (extensors of the spine) can relieve low back pain through anti-spasm and analgesic effect of botulinum toxin.

Detailed description:
This is an investigator initiated, randomized, double blind, placebo-controlled study. A total of 90 patients will be enrolled in the study. The study will be conducted over 4 months. It includes 4 visits and 4 telephone calls. Patients with chronic low back pain (\>3 months) who meet inclusion and exclusion criteria and wish to participate in the study may be enrolled. Those who become enrolled will be scheduled for a baseline visit (Week 0). During the baseline visit, subjects will be given the official approved consent form to read and ask questions. Participants to this study will also receive a copy of the Dysport Risk Evaluation and Mitigation Strategy (REMS) statement. After obtaining informed consent signed by the subject, the subjects will be randomization into the Dysport or placebo group. The randomizing will be performed by a nurse and the information will be kept in a pass-worded computer. Blinding means that neither the participant nor the clinical rater will know which group the participant has been initially been assigned.

Each subject will have a neurological examination and fill a demographic form and complete four rating questionnaires (appendix II-V). These include a visual analogue scale for pain (0 to 10) and three quality of life questionnaires which depict quality of life (the American Chronic Pain Association's Quality of Life Scale), how pain affects ability to manage everyday life (Oswestry Low Back Pain Disability Questionnaire), and overall physical and emotional health (Short Form-36). Patients will then receive an injection of either abobotulinumA (Dysport) or normal saline. Dysport or saline will be administered into the paraspinal muscles (extensors or erector spinae) at five levels (L1-L5), regardless of pain location. In the case of unilateral pain, this would amount to 500 units total, and in the case of bilateral pain, to 1000 units total, of Dysport per session.

The primary outcome of the study is number of patients with VAS \< 4 ( no or subtle pain) at week 6 after placebo or Dysport injection.

Arms:
arm 1: Subjects will be randomization to receive injections with either the study drug (abobotulinumtoxinA) or the placebo group. The subjects will be blinded to which intervention they will receive. arm 2: Subjects will be randomized to receive intervention injections with the study drug arbobotulinumtoxinA.

Interventions: intervention 1: Placebo intervention 2: AbobotulinumtoxinA Treatment
Intervention descriptions: intervention 1: Subjects will be randomization to receive either the study drug or the placebo group. intervention 2: Subjects receive intervention injections with the study drug arbobotulinumtoxinA.

Protocol document: