title: Imageless Navigation Versus Conventional Open Wedge High Tibial Osteotomy: A Meta-Analysis of Comparative Studies.
abstract: OBJECTIVE
  To summarize and compare radiological and clinical outcomes of open wedge high tibial osteotomy (HTO) using imageless computer-assisted navigation with conventional HTO.
  
  
  METHODS
  A literature search of online register databases was conducted. The risk ratio (RR) of radiological outliers and mean differences in clinical outcomes were compared between navigated and conventional HTOs. Radiological results were evaluated by subgroup analyses according to the study period (concurrent/consecutive) and the use of locking fixation device.
  
  
  RESULTS
  Seven comparative studies with a total sample size of 406 knees were included in this review. Radiographically, the mechanical axis [MA] was within the acceptable range (0°-6°) in 83.7% of the navigation HTO group, showing significant difference from 62.1% of the conventional HTO group. Clinically, despite the forest plot demonstrating a general trend of favoring the navigation system, there were not sufficient studies to determine statistical significance in the meta-analysis. None of the subgroup analyses demonstrated significant differences in the RR of MA outliers.
  
  
  CONCLUSIONS
  The present meta-analysis indicates that the use of navigation in open wedge HTO improves the precision of mechanical alignment by decreasing the incidence of outliers; however, the clinical benefit is not conclusive. Additionally, none of the subgroup analyses demonstrated significant difference in the RR of MA outliers.
authors.affiliation: Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Orthopaedic Surgery, Veterans Health Service Medical Center, Seoul, Korea.
authors.forename: Jung-Ro
authors.initials: JR
authors.lastname: Yoon
authors.affiliation: Department of Orthopaedic Surgery, Veterans Health Service Medical Center, Seoul, Korea.
authors.forename: Gi Won
authors.initials: GW
authors.lastname: Choi
authors.affiliation: Department of Orthopaedic Surgery, Veterans Health Service Medical Center, Seoul, Korea.
authors.forename: Jae-Hyuk
authors.initials: JH
authors.lastname: Yang
keywords: Computer-assisted; Meta-analysis; Navigation; Osteotomy; Tibia