Cavanagh Joseph, Lockhart Jason, Langohr G Daniel G, Johnson James A, Athwal George S
Investigations performed at the Roth|McFarlane Hand and Upper Limb Center Biomechanics Laboratory, London, ON, Canada.
JSES Int. 2021 Jul 14;5(5):875-880. doi: 10.1016/j.jseint.2021.05.009. eCollection 2021 Sep.
The humeral head osteotomy during shoulder arthroplasty influences humeral component height, version and possibly neck-shaft angle. These parameters all potentially influence outcomes of anatomic and reverse shoulder replacement to a variable degree. Patient-specific guides and navigation have been studied and utilized clinically for glenoid component placement. Little, however, has been done to evaluate these techniques for humeral head osteotomies. The purpose of this study, therefore, was to evaluate the use of patient-specific guides and surgical navigation for executing a planned humeral head osteotomy.
The DICOM images of 10 shoulder computed tomography scans (5 normal and 5 osteoarthritic) were used to print 3D polylactic models of the humerus. Each model was duplicated, such that there were 2 identical groups of 10 models. After preoperative planning of a humeral head osteotomy, Group 1 underwent osteotomy via a patient-specific guide, while group 2 underwent a real time navigated osteotomy with an optically tracked sagittal saw. The cut height (millimeters), version (degrees) and neck-shaft angle (degrees) were recorded and statistically compared between groups.
There were no statistically significant differences between patient-specific guides and navigation for osteotomy cut height ( = .45) and humeral version ( = .059). Navigation, however, resulted in significantly less neck-shaft angle error than the patient specific guides ( = .023). Subgroup analysis of the osteoarthritic cases showed statistical significance for navigation resulting in less version error than the patient specific guides ( = .048).
No significant differences were found between patient specific guides and navigation for recreation of the preoperatively planned humeral head cut height and version. Neck-shaft angle, however, had significantly less deviation from the preoperative plan when conducted with navigation.
肩关节置换术中肱骨头截骨会影响肱骨假体的高度、旋转角度，可能还会影响颈干角。这些参数都可能在不同程度上影响解剖型和反肩关节置换的效果。针对患者的导板和导航技术已在临床上进行了研究并用于关节盂假体的置入。然而，对于肱骨头截骨术评估这些技术的研究却很少。因此，本研究的目的是评估针对患者的导板和手术导航在实施计划好的肱骨头截骨术中的应用。
使用10例肩部计算机断层扫描（5例正常，5例骨关节炎）的DICOM图像打印肱骨的3D聚乳酸模型。每个模型均被复制，从而有两组各10个相同的模型。在对肱骨头截骨术进行术前规划后，第1组通过针对患者的导板进行截骨，而第2组使用光学跟踪的矢状锯进行实时导航截骨。记录两组截骨的高度（毫米）、旋转角度（度）和颈干角（度），并进行统计学比较。
针对患者的导板和导航在截骨高度（P = 0.45）和肱骨旋转角度（P = 0.059）方面无统计学显著差异。然而，导航导致的颈干角误差明显小于针对患者的导板（P = 0.023）。骨关节炎病例的亚组分析显示，导航导致的旋转角度误差小于针对患者的导板具有统计学意义（P = 0.048）。
针对患者的导板和导航在重现术前规划的肱骨头截骨高度和旋转角度方面未发现显著差异。然而，使用导航进行截骨时，颈干角与术前计划的偏差明显更小。
