Lee Yong Seuk
Seoul National University College of Medicine and Seoul National University Bundang Hospital.
Arthroscopy. 2021 Jul;37(7):2189-2190. doi: 10.1016/j.arthro.2021.03.082.
The tibial slope usually increases after open-wedge high tibial osteotomy (OWHTO) because of several factors. The anteromedial cortex of the proximal tibia is angulated 45° relative to the posterior cortex, whereas the lateral cortex is nearly perpendicular. Therefore, an OWHTO with equal anterior and posterior gaps will increase the tibial slope. In addition, an anteromedial approach to the proximal tibia because of concern about neurovascular injury results in the failure to perform a proper osteotomy of the posterolateral cortex. Slope-optimization methods include a sagittally oriented hinge, posterior bone grafting, posterior plating, and forcefully extending the knee to compress the anterior gap sagittally oriented hinge, posterior positioning of the wedged plate, and knee extension during fixation. However, if the tibial slope is easily controlled using knee extension, this may indicate fracture of the lateral hinge, whereas a preserved lateral hinge is a prerequisite for a successful OWHTO. Most of all, a proper posterior cortical osteotomy is the key step to preventing increased tibial slope in OWHTO. Again, if an incomplete osteotomy is performed posterolaterally, the opening gap is increased anteriorly, leading to an unnecessary increase in posterior tibial slope; for biplanar osteotomy, retrotubercular osteotomy should be performed close to the patellar tendon and not be advanced to the posterolateral side of the hinge.
由于多种因素，在开放性楔形高位胫骨截骨术（OWHTO）后胫骨坡度通常会增加。胫骨近端的前内侧皮质相对于后皮质成45°角，而外侧皮质几乎垂直。因此，前后间隙相等的OWHTO会增加胫骨坡度。此外，由于担心神经血管损伤而采用胫骨近端前内侧入路会导致后外侧皮质截骨操作不当。坡度优化方法包括矢状面定向铰链、后方植骨、后方钢板固定以及强力伸展膝关节以纵向压缩前间隙（矢状面定向铰链、楔形钢板后置以及固定期间膝关节伸展）。然而，如果通过膝关节伸展很容易控制胫骨坡度，这可能表明外侧铰链骨折，而保留外侧铰链是OWHTO成功的先决条件。最重要的是，正确的后皮质截骨是防止OWHTO中胫骨坡度增加的关键步骤。同样，如果后外侧截骨不完全，前方开口间隙会增加，导致胫骨后坡度不必要地增加；对于双平面截骨，应在靠近髌腱处进行结节后截骨，而不应延伸至铰链的后外侧。
