Department of Mechanical Engineering, Polytechnique Montréal, P.O. Box 6079, Downtown Station, Montreal, Quebec H3C 3A7, Canada; Sainte-Justine University Hospital Center, 3175, Cote Sainte-Catherine Road, Montreal, Quebec H3T 1C5, Canada; iLab-Spine (International Laboratory - Spine imaging and Biomechanics), Montreal, Canada and Marseille, France; Laboratoire de Biomécanique Appliquée, IFSTTAR, LBA UMR T24, Aix-Marseille Université, Boulevard Pierre Dramard, Marseille Cedex, France.
Department of Mechanical Engineering, Polytechnique Montréal, P.O. Box 6079, Downtown Station, Montreal, Quebec H3C 3A7, Canada; Sainte-Justine University Hospital Center, 3175, Cote Sainte-Catherine Road, Montreal, Quebec H3T 1C5, Canada; iLab-Spine (International Laboratory - Spine imaging and Biomechanics), Montreal, Canada and Marseille, France.
Clin Biomech (Bristol). 2020 Apr;74:118-123. doi: 10.1016/j.clinbiomech.2020.02.010. Epub 2020 Feb 20.
The sacroiliac joint is an important source of low back pain. In severe cases, sacroiliac joint fusion is used to reduce pain, but revision rates can reach 30%. The lack of initial mechanical stability may lead to pseudarthrosis, thus not alleviating the patient's symptoms. This could be due to the damage induced to the interosseous ligament during implant insertion. Decoupling instrumentation steps (drilling-tapping and implant insertion) would allow verifying this hypothesis. Moreover, no biomechanical studies have been published on sacroiliac joint fixation with an oblique lateral approach, while it has important clinical advantages over the direct lateral approach.
Eight cadaveric human pelves with both ischia embedded were tested in three sequential states: intact, drilled-tapped and instrumented with one cylindrical threaded implant with an oblique lateral trajectory. Specimens were assigned one of two insertion sites (distal point; near the posterior superior iliac spine, and proximal point; anterosuperior to the distal point) and tested in compression and flexion-extension. Vertical and angular displacements of the sacroiliac joint were measured locally using digital image correlation methods.
In compression, instrumentation significantly reduced vertical displacements (17% (SD 22%), P = 0.04) but no difference was found for angular displacements or flexion-extension loads (P > 0.05). Drilling-tapping did not change the stability of the sacroiliac joint (P > 0.05); there was no statistical difference between the insertion sites (P > 0.05).
Insertion of one implant through either the distal or proximal insertion site with an oblique lateral approach significantly reduced vertical displacements of the sacroiliac joint in compression, a predominant load of this joint.
Polytechnique Montreal: CÉR-1617-30.
骶髂关节是腰痛的一个重要来源。在严重的情况下，采用骶髂关节融合术来减轻疼痛，但翻修率可达 30%。初始机械稳定性不足可能导致假关节形成，从而无法缓解患者的症状。这可能是由于在植入物插入过程中对骨间韧带造成的损伤。分离器械步骤（钻孔-攻丝和植入物插入）将验证这一假设。此外，尚无关于斜外侧入路固定骶髂关节的生物力学研究，而该入路与直接外侧入路相比具有重要的临床优势。
对 8 具带有坐骨的成人骨盆尸体进行了三个连续状态的测试：完整、钻孔-攻丝和用一个带有斜外侧轨迹的圆柱形螺纹植入物进行器械化。标本被分配到两个插入点之一（远端点；靠近后上髂棘，近端点；远端点的前上），并在压缩和屈伸测试中进行测试。使用数字图像相关方法在局部测量骶髂关节的垂直和角度位移。
在压缩时，器械化显著降低了垂直位移（17%（SD 22%），P=0.04），但在角度位移或屈伸负荷方面没有差异（P>0.05）。钻孔-攻丝不会改变骶髂关节的稳定性（P>0.05）；插入点之间没有统计学差异（P>0.05）。
通过斜外侧入路从远端或近端插入点插入一个植入物，显著降低了骶髂关节在压缩时的垂直位移，这是该关节的主要负荷。
蒙特利尔理工学院：CER-1617-30。
