Mazdarani P, Gundersen R S, Nielsen M B M, von Wenck A, Miles J E
Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
Vetgruppen, Hovedgaden 12, 3460 Birkerød, Denmark.
Res Vet Sci. 2022 Jul;145:229-237. doi: 10.1016/j.rvsc.2022.03.007. Epub 2022 Mar 8.
Tibial plateau levelling osteotomy is widely performed for stabilization of cranial cruciate ligament deficient stifles in dogs. A wide range of postoperative tibial plateau angles around the target angle has been reported. The main aim of this study was to investigate if osteotomy placement could explain this range. Landmarks were derived from 50 tibial radiographs by five observers and used to define osteotomy placement and correction angles for simulation. Observer-specific osteotomy locations with mean landmark data were used to simulate planning errors, and simulated malpositioning of the osteotomy at 5 mm and 10 mm from the ideal location was used to simulate surgical errors. The tibial plateau midpoint was used as the ideal centre of the osteotomy in this model. Planning errors mostly arose from tibial plateau misidentification, with osteotomy centre locations dispersed up to 2.4% of tibial length from ideal. Malpositioning of the osteotomy resulted in variable changes in tibial plateau angle. Synthesis with historical data suggested such changes are likely limited in magnitude in tibiae with a mechanical axis length over 140 mm, but will be greater in smaller dogs and with steeper tibial plateaus. In medium to large breed dogs, our findings indicate osteotomy inaccuracy alone cannot explain the reported postoperative ranges in tibial plateau angles. Other error sources such as rotational inaccuracies or shifts during implant placement may be more significant. Surgeons should exercise additional caution when operating small and miniature breeds due to the much larger potential for clinically significant errors in these smaller dogs.
胫骨平台水平截骨术广泛应用于犬类颅交叉韧带缺失膝关节的稳定治疗。已有报道称术后胫骨平台角度围绕目标角度存在较大范围。本研究的主要目的是调查截骨位置是否能解释这一范围。五名观察者从50张胫骨X光片中获取标志点，并用于定义截骨位置和模拟矫正角度。使用具有平均标志点数据的观察者特定截骨位置来模拟计划误差，并将截骨在距理想位置5毫米和10毫米处的模拟错位用于模拟手术误差。在该模型中，胫骨平台中点被用作截骨的理想中心。计划误差主要源于胫骨平台识别错误，截骨中心位置偏离理想位置达胫骨长度的2.4%。截骨的错位导致胫骨平台角度发生不同变化。与历史数据综合分析表明，对于机械轴长度超过140毫米的胫骨，这种变化幅度可能有限，但在体型较小的犬类以及胫骨平台更陡的情况下变化会更大。在中大型犬中，我们的研究结果表明，仅截骨不准确无法解释所报道的术后胫骨平台角度范围。其他误差来源，如植入物放置过程中的旋转不准确或移位，可能更为显著。由于这些较小犬类出现临床显著误差的可能性大得多，外科医生在为小型和微型犬手术时应格外谨慎。
