Cost-effectiveness of open transforaminal lumbar interbody fusion (OTLIF) versus minimally invasive transforaminal lumbar interbody fusion (MITLIF): a systematic review and meta-analysis

The number of performed instrumented lumbar spine surgeries and associated health-care-related costs has increased over the last decades, and will increase further in the future. With the consistent growth of health-care-related costs, cost-effectiveness of surgical techniques is of major relevance. Common indications for instrumented lumbar spine surgery are spondylolisthesis and degenerative disease. A commonly used technique is the open transforaminal lumbar interbody fusion (OTLIF). Nowadays, there is an increasing interest in the minimally invasive variation of this technique (minimally invasive transforaminal lumbar interbody fusion [MITLIF]). Currently available literature describes that MITLIF has comparable or even better clinical results compared to OTLIF. Cost-effectiveness of MITLIF and OTLIF is important considering the growing health-care related costs, although no consensus has been reached regarding the most cost-effective technique. In this systematic review, previous literature concerning costs and cost-effectiveness of OTLIF was compared with MITLIF in patients with lumbar spondylolisthesis or degenerative disease. Furthermore, methodological quality of included studies was assessed. This study aims to evaluate the current literature on cost-effectiveness of OTLIF compared MITLIF to in patients with lumbar spondylolisthesis or degenerative disease. This study is a systematic literature review and meta-analysis. Clinical studies reporting costs or cost-effectiveness for either OTLIF or MITLIF in patients with spondylolisthesis, lumbar instability, or degenerative disease were included. The following data items were evaluated: study design, study population, utility measurement tool, gained quality adjusted life years (QALYs), cost sources, health care and societal perspective costs, total costs, costs per QALY (cost-effectiveness) and incremental cost-effectiveness ratio (ICER). A systematic search was conducted using databases PubMed, CINAHL, EMBASE, Cochrane, Clinical Trials, Current Controlled Trials, ClinicalTrials.gov, NHS Centre for Review and Dissemination, Econlit and Web of Science on studies reporting OTLIF or MITLIF, spondylolisthesis or lumbar instability or degenerative disease, and costs. Relevant studies were selected and reviewed independently by two authors. For comparison, all costs were converted to American dollars with the reference year 2018. After duplicate removal, a total of 892 studies were identified. Eventually