Applicability of a modified angular correction measurement method for open-wedge high tibial osteotomy

The purpose of this study was to evaluate the clinical potential of a new measurement technique for open-wedge high tibial osteotomy (HTO) based on the medial cortex opening (MCO) associated with the Miniaci preoperative planning technique. A retrospective review of 97 cases of valgus-producing HTO that were performed between 2008 and 2013, using the intra-operative fluoroscopic mechanical axis technique, was carried out. The Miniaci-based measurement technique was then used as a theoretical point of comparison with the intent to compare the disparity between postoperative and ideal lower extremity (LE) mechanical axis with the measured disparity between postoperative and Miniaci-based planned MCO. A significant correlation was observed for the comparison of the disparity between postoperative and Miniaci-based planned MCO and the disparity between postoperative and ideal LE mechanical axis (0.53, P = 0.001). This would suggest that the MCO associated with the Miniaci preoperative planning technique would have resulted in a better alignment had it been the chosen method to guide the amount of osteotomy opening. No significant correlation was observed between perioperative and postoperative LE mechanical axis (n.s.), the variable on which the current technique is based, confirming the poor reliability of the fluoroscopic mechanical axis technique. This study suggests a more accurate and precise technique of realizing the appropriate angular correction when performing a HTO, which could lead to better clinical outcomes. III.