The influence of ligament biomechanics on proximal junctional kyphosis and failure in patients with adult spinal deformity

IF 3.4 3区医学 Q1 ORTHOPEDICS

JOR Spine Pub Date : 2023-08-25 DOI:10.1002/jsp2.1277

Micah Blais, Bahar Shahidi, Brad Anderson, Eli O'Brien, Courtney Moltzen, Tina Iannacone, Robert K. Eastlack, Gregory M. Mundis Jr

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Abstract

Purpose

It is unknown whether the biomechanics of the posterior ligamentous complex (PLC) are impaired in individuals undergoing surgery for adult spinal deformity (ASD). Characterizing these properties may improve our understanding of proximal junctional kyphosis (PJK; defined as proximal junctional angle [PJA] of >10 deg from UIV-1 to UIV + 2), as well as proximal junctional failure (PJF; symptomatic PJK requiring revision). The purpose of this prospective observational study is to compare biomechanical properties of the PLC in individuals with ASD who do, and do not develop PJK or PJF within 1 year of spinal fusion surgery.

Methods

Intraoperative biopsies of PLC were obtained from 32 consecutive patients undergoing spinal fusions for ASD (>4 levels). Ligament peak force, tensile stress, tensile strain, and elastic modulus (EM) were measured with a materials testing system. Biomechanical properties and tissue dimensions were correlated with age, gender, BMI, vitamin D level, osteoporosis, sagittal alignment, PJA and change in PJA preoperatively, within 3 months, and at 1 year postoperatively.

Results

Longer ligaments were associated with greater PJA change at 3 months (p = 0.04), and thinner ligaments were associated with greater PJA change at 1 year (r = 0.57, p = 0.01). Greater EM was associated with greater PJA at both 3 months and 1 year (p = 0.03). Five participants had a change in PJA of >10 1 year postoperatively, and three participants demonstrated PJF. EM was significantly higher in individuals who required revision surgery (p = 0.003), and ligament length was greater (p = 0.03). Preoperative sagittal alignment was not related to incidence of revision surgery (p > 0.10).

Conclusions

The biomechanical properties of the PLC may be associated with higher risk for proximal failure. Ligaments that are longer, thinner, and less elastic are associated with higher postoperative PJA. Furthermore stiffer EM of the ligament is associated with the need for revision surgery.

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查看原文本刊更多论文

韧带生物力学对成人脊柱畸形患者近端连接后凸和失败的影响。

目的：尚不清楚接受成人脊柱畸形（ASD）手术的患者后韧带复合体（PLC）的生物力学是否受损。描述这些特性可以提高我们对近端交界后凸的理解（PJK；定义为>10的近端交界角[PJA] 从UIV-1到UIV的度数 + 2），以及近端连接衰竭（PJF；症状性PJK需要翻修）。这项前瞻性观察性研究的目的是比较患有和未在1 脊柱融合手术年。方法：对32例因ASD（>4级）接受脊柱融合术的连续患者进行术中PLC活检。使用材料测试系统测量韧带峰值力、拉伸应力、拉伸应变和弹性模量（EM）。生物力学特性和组织尺寸与年龄、性别、BMI、维生素D水平、骨质疏松症、矢状位对齐、PJA和术前PJA的变化相关月，在1 术后一年。结果：韧带越长，PJA变化越大月（p = 0.04），并且较薄的韧带与1 年（r = 0.57，p = 0.01）。EM越大，PJA越大月和1 年（p = 0.03）。五名参与者的PJA变化>10 1 术后一年，三名参与者表现出PJF。EM在需要翻修手术的个体中显著较高（p = 0.003），韧带长度更大（p = 术前矢状位对齐与翻修手术的发生率无关（p > 0.10）。结论：PLC的生物力学特性可能与更高的近端衰竭风险有关。较长、较薄、弹性较低的韧带与术后PJA较高有关。此外，韧带的EM变硬与翻修手术的需要有关。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

JOR Spine ORTHOPEDICS-

CiteScore

6.40

自引率

18.90%

发文量

审稿时长

10 weeks