Northwest Orthopaedic Specialists, Spokane, Washington;
J Neurosurg Spine. 2011 Jan;14(1):31-7. doi: 10.3171/2010.9.SPINE09871. Epub 2010 Dec 17.
because the psoas muscle, which contains nerves of the lumbar plexus, is traversed during the extreme lateral interbody fusion (XLIF) approach, appropriate nerve monitoring is needed to avoid nerve injury during surgery and prevent approach-related neural deficit. This study was performed to assess the effectiveness of dynamically evoked electromyography (EMG) to detect and prevent neural injury during the XLIF approach.
one hundred two patients undergoing XLIF at L3-4 and/or L4-5 were enrolled in a prospective, multicenter, nonrandomized clinical study. The EMG threshold values for each of the 3 successive dilators were recorded at the surface of the psoas muscle, mid-psoas, and on the spine. At each location, the dilators were rotated 360°, taking recordings immediately posterior, superior, anterior, and inferior. For each dilator, the authors noted the rotational position (the angle in degrees) at which the lowest threshold was found. Findings of pre- and postoperative neurological examinations were also recorded.
nerves were identified within proximity of the dilators (alert-level EMG feedback) in 55.7% of all cases during the XLIF approach. Although nerves were more commonly identified in the posterior margin (63%), there was significant variability in the location of nerves identified. Despite the fact that the posterior half of the disc space was targeted in 90% of cases, no significant long-lasting neural deficits were identified in any case; 27.5% experienced new iliopsoas/hip flexion weakness and 17.6% experienced new postoperative upper medial thigh sensory loss. Transient motor deficits were identified in 3 patients (2.9%), and all had resolved by the 6-month follow-up visit.
the ability to identify and report a discrete, real-time EMG threshold during the transpsoas approach helps to avoid nerve injury and is required for the safe performance of the XLIF procedure. Additionally, nerve location is variable, thus reinforcing the need for real-time directional and proximity information.
因为腰丛神经穿过腰大肌，所以在极外侧椎间融合术（XLIF）过程中需要进行适当的神经监测，以避免手术过程中的神经损伤，并预防与手术入路相关的神经缺陷。本研究旨在评估动态诱发肌电图（EMG）在 XLIF 过程中检测和预防神经损伤的有效性。
102 例在 L3-4 和/或 L4-5 行 XLIF 的患者被纳入前瞻性、多中心、非随机临床研究。在腰大肌表面、腰大肌中部和脊柱上记录每个连续扩张器的 3 次扩张器的 EMG 阈值。在每个位置，扩张器旋转 360°，在后方、上方、前方和下方立即进行记录。对于每个扩张器，作者记录了找到最低阈值的旋转位置（以度为单位的角度）。还记录了术前和术后神经检查的结果。
在 55.7%的 XLIF 过程中，神经在扩张器附近被识别（警示级别的 EMG 反馈）。尽管神经更常见于后缘（63%），但识别到的神经位置存在显著差异。尽管 90%的病例都针对椎间盘的后半部分，但在任何情况下都没有发现明显的长期神经缺陷；27.5%的患者出现新的髂腰肌/髋关节屈曲无力，17.6%的患者出现新的术后大腿内侧上部感觉丧失。3 名患者（2.9%）出现短暂性运动障碍，所有患者在 6 个月随访时均已恢复。
在经腰大肌入路过程中识别和报告离散、实时 EMG 阈值的能力有助于避免神经损伤，是 XLIF 手术安全进行的必要条件。此外，神经位置是可变的，因此需要实时的方向和接近信息。
