Complications in Thoracic Minimally Invasive Spine Surgery (2013–2024): A Systematic Review

Background/Objectives: Thoracic minimally invasive spine surgery (MISS) offers reduced tissue trauma and faster recovery compared with open approaches, but its adoption remains limited due to technical complexity and uncertainty regarding complication rates. This study aimed to synthesize the available evidence on overall and approach-specific complications of thoracic MISS using tubular, uniportal endoscopic, and biportal endoscopic techniques. Methods: Following PRISMA guidelines (PROSPERO CRD42024594316), PubMed, Medline, Embase, and Cochrane Library were searched from January 2013 to March 2024 for studies reporting complication rates after thoracic MISS in adults. Eligible studies included tubular, uniportal, or biportal approaches. Study quality was assessed using the Newcastle–Ottawa Scale. Complication data were extracted and summarized descriptively, with reported rates stratified by surgical approach. Results: Nine studies (234 patients) were included, all retrospective with moderate risk of bias. Across included studies, reported overall complication rates following thoracic MISS ranged from 0% to 42.9%. Stratified by surgical approach, reported complication rates ranged from 0% to 11.8% across six tubular studies, 9.7% to 20.0% across two uniportal endoscopic studies, and 42.9% in a single small biportal endoscopic study. Neural injuries and dural tears were the most frequently reported complications, with reported rates ranging from 0% to 14.3% and 0% to 3.6%, respectively. Symptomatic cerebrospinal fluid leaks and revision surgeries were less common, with reported rates ranging from 0% to 11.8% and 0% to 3.2%, respectively. Conclusions: Thoracic MISS demonstrates a low overall complication rate, particularly for tubular approaches. However, findings should be interpreted with caution given the small number of included studies, retrospective designs, and clinical heterogeneity. Larger comparative investigations are needed to better define safety profiles and support broader adoption of thoracic MISS techniques.