midas iii (mild® decompression alternative to open surgery): vertos mild patient evaluation study

Conditions: Lumbar Spinal Stenosis

Summary: this is a multi-center, prospective, observational clinical study to compare patient outcomes following treatment with either the mild® procedure or epidural steroid injection in patients with moderate to severe lumbar spinal stenosis exhibiting neurogenic claudication.

the study was initially designed as a randomized trial. due to difficulty of enrollment, the study was amended and converted to an observational comparative study with study arm being self-selected by the patient.

Eligibility criteria:
inclusion criteria: * lumbar spinal stenosis (lss) with neurogenic claudication where the visual analog scale (vas) of back and leg pain average is ≥ 5. * prior failure of conservative therapy. * oswestry disability index (odi) score of ≥ 31%. * radiologic evidence of lss, with unilateral or bilateral ligamentum flavum ≥ 4.1mm confirmed by pre-op mri performed within 6-12 months of baseline visit. * able to walk ≥ 10 feet before being limited by pain. * available to complete 24-months of follow-up. * adults ≥ 50 years of age. exclusion criteria: * prior surgery at intended treatment level. * history of spinal fractures with current related pain symptoms. * motor deficit or disabling back and/or leg pain from causes other than lss neurogenic claudication (e.g. acute compression fracture, metabolic neuropathy, vascular claudication symptoms, etc.). * significant/symptomatic disc protrusion or osteophyte formation judged by the investigator as possible confounding factor to study results. * excessive facet hypertrophy judged by the investigator as possible confounding factor to study results. * significant symptomatic foraminal stenosis. * confirmed anterior or retro-listhesis ≥ 3mm. * bleeding disorders and/or current use of anti-coagulants with the inability to withhold anticoagulants for required time prior to procedure. * able to walk ≥ 200 yards unaided in erect non-flexed position before being limited by pain. * able to stand ≥ 15 minutes in erect, non-flexed position before being limited by pain. * use of acetylsalicylic acid (asa) and/or non-steroidal anti-inflammatory drug (nsaid) within 7 days of treatment. * pregnant and/or breastfeeding. * body mass index (bmi) ≥ 32 as calculated using the patient's weight multiplied by 703 then divided by height in inches squared. * epidural steroid, systemic steroid or any spine interventional procedure within prior six weeks of study procedure. * dementia and/or inability to give informed consent and to understand and complete follow-up patient reported outcomes forms. * inability of the patient to lie prone for any reason with anesthesia support (e.g. chronic obstructive pulmonary disease (copd), obesity, etc.). * on (or pending) workman's compensation or known to be considering litigation associated with back pain. * unable to tolerate mri (pacemaker, spinal cord stimulator, etc.). * intrathecal pump. * any medical condition determined by the investigator that would not allow subject to fulfill trial requirements or safely tolerate procedures in this study.