Wide Variability in Patient-Reported Outcomes Measures After Fusion for Lumbar Spinal Stenosis: A Systematic Review

STUDY DESIGN: Systematic review. OBJECTIVES: The purpose of this study is to review outcomes reporting methodology in studies evaluating fusion for lumbar spinal stenosis. METHODS: A systematic review of PubMed and Embase databases was conducted from January 2007 to June 2017 for English language studies with minimum of 2 years postoperative follow-up reporting outcomes after fusion for lumbar spinal stenosis. Two reviewers assessed each study; those meeting inclusion criteria were examined for pertinent data. Outcome measures were categorized into relevant domains: pain/symptomatology, function/disability, and surgical satisfaction. Return to work reporting was also recorded. RESULTS: Of 123 studies meeting inclusion criteria, 76% included posterior-only fusion, 32% included posterior/transforaminal interbody fusion, and 5% included anterior/lateral interbody fusion (non-mutually exclusive). There was significant variation in patient-reported outcomes (PROs) used—studies reported 31 unique PROs assessing at least one domain: 22 evaluating pain, 23 evaluating function, and 3 evaluating surgical satisfaction. Most commonly utilized PROs were the Oswestry Disability Index (73% of studies), Visual Analog Scale (55%), and 36-Item Short Form Survey (32%). The remaining 28 measures were used in 14% of studies or fewer. PROs specific to symptoms of lumbar spinal stenosis, such as the Zurich Claudication Questionnaire, were only used rarely (7/123 studies). Only 14% of studies reported on time to return to work. CONCLUSIONS: The literature surrounding fusion in the setting of lumbar stenosis is characterized by substantial variability in outcomes reporting. Very few studies utilized measures specific to lumbar spinal stenosis. Efforts to standardize outcomes reporting would facilitate comparisons of surgical interventions.