Center for Spine Surgery, Neckar-Odenwald-Kliniken gGmbH Buchen, Buchen, Germany.
Spine (Phila Pa 1976). 2020 Apr 1;45(7):421-430. doi: 10.1097/BRS.0000000000003293.
Retrospective radioanatomic single-center cohort study.
To investigate sex-specific differences in transsacral corridor dimensions, determine feasibility rates of transsacral screw placement without extended safety zones around planned screw positions, and develop an index defining sacral dysmorphism (SD) irrespective of transsacral corridor diameters.
Previously reported SD definitions used radiologically identifiable pelvic characteristics or predefined minimum diameter thresholds of transsacral corridors in the upper sacral segment including safety zones for screw placement. Technical progress of surgical 3D image guidance improved sacral screw insertion accuracy questioning established minimum diameter threshold-based SD definitions.
Datasets from cross-sectional pelvic imaging of 100 women and 100 men presenting to a general hospital from July 2018 through August 2018 were included in a database to evaluate transsacral trajectory rates, and dimensions of transsacral corridor lengths, widths (TSCWs), and heights (TSCHs) in sacral segments I to III (S1-3). SD was assumed, if no transsacral trajectory was found in S1 with a corridor diameter of at least 7.5 mm.
Women presented significantly higher rates of transsacral trajectories in the inferior sector of S1 (P = 0.03), and larger transsacral corridor lengths in S2 (superior sector, P = 0.045), and S3 (central position, P = 0.02). In men, significantly higher feasibility rates were found for the placement of two transsacral screws in S2 (P = 0.0002), and singular screws in S3 (P = 0.006), with larger S1- (P = 0.0002), and central S2-TSCWs (P = 0.006). SD was prevalent in 17% of women, and 16% of men (P = 0.85). Calculating TSCW ratios of S1 and S2 was significantly indicative for SD at values below a threshold of 0.8 in women (P < 0.00001), and men (P = 0.0004).
SD is independent of sex despite significant differences in sacral morphology. An index defining SD irrespective of absolute transsacral corridor dimensions is presented to reliably differentiate dysmorphic from nondysmorphic sacra in women and men.
回顾性放射解剖学单中心队列研究。
研究经骶骨通道的性别特异性差异，确定不在计划螺钉位置周围的扩展安全区的情况下进行经骶骨螺钉放置的可行性率，并开发一种定义骶骨畸形（SD）的指数，而不考虑经骶骨通道直径。
先前报道的 SD 定义使用放射可识别的骨盆特征或在上骶段的经骶骨通道中使用预定义的最小直径阈值，包括螺钉放置的安全区。手术 3D 图像引导技术的进步提高了骶骨螺钉插入的准确性，对基于最小直径阈值的 SD 定义提出了质疑。
将 2018 年 7 月至 8 月期间在一家综合医院就诊的 100 名女性和 100 名男性的横断面骨盆影像学数据集纳入数据库，以评估经骶骨轨迹率，以及骶骨节段 I 至 III（S1-3）的经骶骨通道长度、宽度（TSCWs）和高度（TSCHs）的尺寸。如果在 S1 中发现至少 7.5mm 的通道直径没有经骶骨轨迹，则假设存在 SD。
女性在 S1 的下象限中呈现出更高的经骶骨轨迹率（P=0.03），并且 S2（上象限，P=0.045）和 S3（中央位置，P=0.02）的经骶骨通道长度更大。在男性中，发现 S2 中双经骶骨螺钉（P=0.0002）和 S3 中单经骶骨螺钉（P=0.006）的放置可行性率显著更高，S1-（P=0.0002）和中央 S2-TSCWs（P=0.006）更大。17%的女性和 16%的男性存在 SD（P=0.85）。在女性中，S1 和 S2 的 TSCW 比值低于 0.8 的阈值（P<0.00001），在男性中，该比值低于 0.8 的阈值（P=0.0004），具有显著的 SD 指示意义。
尽管骶骨形态存在显著差异，但 SD 与性别无关。提出了一种定义 SD 的指数，该指数不考虑经骶骨通道的绝对尺寸，可用于可靠地区分女性和男性中畸形和非畸形骶骨。
2 级。
