Data from: Novel TPLO alignment jig/saw guide reproduces freehand and ideal osteotomy positions

Objectives: To evaluate the ability of an alignment jig/saw guide to reproduce appropriate osteotomy positions in the tibial plateau leveling osteotomy (TPLO) in the dog. Methods: Lateral radiographs of 65 clinical TPLO procedures using an alignment jig and freehand osteotomy performed by experienced TPLO surgeons using a 24 mm radial saw blade between Dec 2005 - Dec 2007 and Nov 2013 - Nov 2015 were reviewed. The freehand osteotomy position was compared to potential osteotomy positions using the alignment jig/saw guide. The proximal and distal jig pin holes on postoperative radiographs were used to align the jig to the bone; saw guide position was selected to most closely match the osteotomy performed. The guide-to-osteotomy fit was categorized by the distance between the actual osteotomy and proposed saw guide osteotomy at its greatest offset (?1 mm = excellent; ?2 mm = good; ?3 mm = satisfactory; >3 mm = poor). Results: Sixty-four of 65 TPLO osteotomies could be matched satisfactorily by the saw guide. Proximal jig pin placement 3-4 mm from the joint surface and location in a craniocaudal plane on the proximal tibia was significantly associated with the guide-to-osteotomy fit (P = 0.021 and P = 0.047, respectively). Clinical significance: The alignment jig/saw guide can be used to reproduce appropriate freehand osteotomy position for TPLO. Furthermore, an ideal osteotomy position centered on the tibial intercondylar tubercles also is possible. Accurate placement of the proximal jig pin is a crucial step for correct positioning of the saw guide in either instance.研究目的：评估定位夹具/锯导板（alignment jig/saw guide）在犬胫骨平台水平截骨术（tibial plateau leveling osteotomy, TPLO）中复刻合适截骨位置的能力。 研究方法：回顾性分析2005年12月至2007年12月、2013年11月至2015年11月期间，由经验丰富的TPLO手术医师使用24mm弧形锯片完成的65例采用定位夹具辅助与徒手截骨的临床TPLO手术的侧位X线片。将徒手截骨的位置与使用定位夹具/锯导板的预设截骨位置进行比对。通过术后X线片上的近端与远端夹具销孔将夹具与骨骼对齐；选取与实际完成的截骨最为贴合的锯导板位置。以实际截骨与预设锯导板截骨之间的最大偏移距离对导板与截骨的贴合度进行分级：≤1mm为优秀；≤2mm为良好；≤3mm为合格；＞3mm为不合格。 研究结果：65例TPLO截骨术中，有64例可通过锯导板实现合格贴合。距离关节面3~4mm的近端夹具销钉放置位置，以及胫骨近端的颅尾侧平面定位，与导板-截骨贴合度显著相关（分别对应P=0.021与P=0.047）。 临床意义：定位夹具/锯导板可用于复刻TPLO手术中合适的徒手截骨位置。此外，以胫骨髁间结节为中心的理想截骨位置同样可通过该装置实现。无论采用何种方式，精准放置近端夹具销钉都是确保锯导板位置准确的关键步骤。