Background:Numerous studies have compared suprapatellar (SP) nailing to infrapatellar (IP) nailing for treatment of tibial shaft fractures; however, the best strategy remains controversial. The aim of this meta-analysis is to assess whether SP or IP nailing is more effective for tibial shaft fractures in adults.Methods:Literature searches of PubMed, Embase, OVID, Cochrane Library, Web of Science, Chinese Biomedical Literature, Wanfang, Weipu Journal, and CNKI databases were performed up to July 2017. Only randomized controlled trials (RCTs) comparing SP versus IP intramedullary nailing for tibial shaft fractures were included. Data collection and extraction, quality assessment, and data analyses were performed according to the Cochrane standards.Results:Twelve RCTs were selected for analysis. SP intramedullary nailing reduced knee joint pain, visual analog score, fluoroscopy time, and sagittal angle, resulting in better Harris hip score, Lysholm knee score, short-form 36 questionnaire, range of motion, and rates of “excellent” and “good” outcome. There were no significant differences in operative time, blood loss, length of hospital stay, union time, and coronal angle between groups.Conclusion:The present meta-analysis indicates that SP intramedullary nailing has obvious advantages over IP intramedullary nailing for treatment of tibial shaft fractures in adults. However, owing to the low-quality evidence currently available, additional high-quality RCTs are needed to confirm these findings.