Solomin L N, Chugaev D V, Filippova A V, Kulesh P N
National Medical Research Center of Traumatology and Orthopedics, Saint Petersburg State University, Saint Petersburg, Russia, Russian Federation.
Department Saint Petersburg State University, Saint Petersburg, Russia, Russian Federation.
Strategies Trauma Limb Reconstr. 2020 Jan-Apr;15(1):13-22. doi: 10.5005/jp-journals-10080-1449.
The surgical technique of proximal tibial osteotomy for genu varum in adults has evolved from a procedure using closing wedges of estimated sizes with staple fixation in the 1960s to using standard trauma internal fixation implants and, more recently, to gradual correction with software-guided hexapod external fixators. In the last two decades, implant manufacturers have also produced anatomical implants specific for such corrective osteotomies. This study evaluates the limits of using such proprietary implants for proximal tibial osteotomy in genu varum.
Scanograms (teleradiograms) of lower limbs of a patient were used to derive skiagrams (two-dimensional bony outlines of the extremities). From these, two-dimensional and three-dimensional models of varus deformities of the tibia with different values of mechanical medial proximal tibial angle (mMPTA, from 85° to 40°) were created. An analysis of the created deformity was carried out and a simulation for surgical correction was performed using an open wedge high tibial osteotomy with fixation using a proprietary (Tomofix, Synthes) implant. In addition, a 3D simulation technique was used to check the accuracy of the results obtained from the 2D simulation.
In cases of mMPTA ≥80° with localisation of the apex of varus deformity at the level of the knee joint line, the standard technique used with the proprietary medial tibial plate produces good results.In cases of mMPTA ≤70°, fixation of the osteotomised fragments by the proprietary medial plate is poor owing to the anatomical contours of the implant. In these cases, a different type of osteosynthesis is needed.In cases of mMPTA ≤70°, the distance between the lower edge of the bone plate and the medial surface of the tibia after a proximal tibial osteotomy exceeds 11 mm and will result in unacceptable soft tissue tension around the implant.Mechanical axis deviation to the Fujisawa point produces mMPTA values outside the reference range of normal values.
An osteotomy of the proximal tibia using a prescribed technique linked to a proprietary implant achieves good results only if performed within a certain range of deformity values. Pronounced varus deformities require a fundamentally different approach. This study reveals that surgeons undertaking corrective proximal tibial osteotomies for genu varum need to perform a comprehensive analysis of the deformity to allow for appropriate selection of patients. This will enable a consideration of the size and other characteristics of the deformity that will reduce the technical complications that may arise if the correction was performed using the recommended technique linked to a proprietary implant.
Solomin LN, Chugaev DV, Filippova AV, High Tibial Osteotomy for Genu Varum in Adults: Do Proprietary Implants Limit the Quality of Correction? Strategies Trauma Limb Reconstr 2020;15(1):13-22.
成人膝内翻胫骨近端截骨术的手术技术已从20世纪60年代使用估计尺寸的闭合楔形并用U形钉固定的手术，发展到使用标准创伤内固定植入物，以及最近使用软件引导的六足外固定器进行逐步矫正。在过去二十年中，植入物制造商还生产了专门用于此类矫正截骨术的解剖型植入物。本研究评估了使用此类专利植入物进行成人膝内翻胫骨近端截骨术的局限性。
使用患者下肢的扫描X线片（远距离X线照片）得出骨骼X线片（四肢的二维骨骼轮廓）。由此创建了具有不同机械性胫骨近端内侧角（mMPTA，从85°到40°）值的胫骨内翻畸形的二维和三维模型。对创建的畸形进行分析，并使用专利（Tomofix，Synthes）植入物固定的开放楔形高位胫骨截骨术进行手术矫正模拟。此外，使用3D模拟技术检查从2D模拟获得的结果的准确性。
在mMPTA≥80°且内翻畸形顶点位于膝关节线水平的情况下，使用专利内侧胫骨钢板的标准技术产生良好效果。在mMPTA≤70°的情况下，由于植入物的解剖轮廓，专利内侧钢板对截骨碎片的固定较差。在这些情况下，需要不同类型的骨接合术。在mMPTA≤70°的情况下，胫骨近端截骨术后骨板下缘与胫骨内侧表面之间的距离超过11mm，会导致植入物周围不可接受的软组织张力。机械轴偏向藤泽点会使mMPTA值超出正常参考范围。
使用与专利植入物相关的规定技术进行胫骨近端截骨术，仅在一定畸形值范围内进行才能取得良好效果。明显的内翻畸形需要根本不同的方法。本研究表明，进行成人膝内翻矫正性胫骨近端截骨术的外科医生需要对畸形进行全面分析，以便适当选择患者。这将能够考虑畸形的大小和其他特征，从而减少如果使用与专利植入物相关的推荐技术进行矫正可能出现的技术并发症。
索洛明LN，丘加耶夫DV，菲利波娃AV，成人膝内翻高位胫骨截骨术：专利植入物会限制矫正质量吗？《创伤肢体重建策略》2020；15（1）：13 - 22。
