intraarticular lumbar joint corticosteroid injection(s) as a treatment of chronic low back pain in a selected population

Conditions: Low Back Pain

Summary: subjects (n=120) who have had non-radicular low back pain, believed by clinical assessment and imaging to be consistent with lumbar zygapophysial joint (z-joint) generated pain, who have failed conservative therapy including physical therapy, have had an initial \>80% pain relief on a diagnostic medial branch block, and are scheduled to undergo a routine second medial branch block for facet mediated pain will be randomized. both groups will receive the standard of care, a medial branch block. the treatment group will also receive one set of intra-articular lumbar z-joint corticosteroid injection and the placebo group will receive intra-articular normal saline.

subjects will have failed conservative treatment, including, but not limited to oral medications, physical therapy, chiropractic treatment, and/or alternative medicine. they will be evaluated by a spine specialist in the spine division of the department of orthopaedics and will be schedule for a medial branch block as standard of care. as part of usual and standard care, patients will undergo lumbar medial branch blocks for diagnosis of zygapophysial joint pain. patients who obtain ≥ to 80% relief of their index pain with a first set of lumbar medial branch blocks will be offered the opportunity for possible inclusion in the study if they are scheduled to receive a second medial branch block. the definition of a positive response to mbb's is an 80% reduction in pain (by change in npr scores or estimated patient improvement) and the restoration of the ability to perform at least one previously painful posture, movement, or activity without increase in pain, during the anesthetic phase of the blocks. if subjects are unable to render npr scores or percentage estimate of improvement, then a 5 point global perception of effect tool will be used.

Eligibility criteria:
inclusion criteria: * low back pain episode greater than six months in duration * npr pain scale score three day average and present pain of at least four/ten at baseline (index pain) * previous medial branch block providing \>80% pain relief for current painful episode * subject must be scheduled to undergo a second medial branch block for their back pain exclusion criteria: * litigation * those seeking new or increased long-term remuneration * leg pain greater than back pain * radicular pain or evidence of neurological compromise in the lower limbs * those unable to read english and complete the assessment instruments * systemic inflammatory arthritis (e.g. rheumatoid, lupus) * addictive behavior, severe clinical depression or psychotic features. the subjects will be identified at the sole discretion of the pi who per the current standard of care will consent the potential subjects to the study * significant lower extremity pathology that affects gait * sustained cervical or thoracic pain that is present at a level \>3/10 on npr * possible pregnancy or other reason that precludes the use of fluoroscopy * significant scoliosis * radicular/neurological deficits or focal disc herniation and/or stenosis, with correlating radicular symptoms * contra-indication to corticosteroid, including known allergies or sensitivities * history of prior epidural spinal injections relieving their current pain, or prior lumbar surgery.

Keywords: low back pain zygapophysial joint pain medial branch block > 6 months duration non-radicular