弥漫性特发性骨质增生症伴腰椎管狭窄症的影像学特征

Imaging features of lumbar spinal stenosis in patients with diffuse idiopathic skeletal hyperostosis

中文关键词:  腰椎管狭窄症  弥漫性特发性骨质增生症  影像学特征

英文关键词:Lumbar spinal stenosis  Diffuse idiopathic skeletal hyperostosis  Imaging features

中文摘要:

  【摘要】 目的：探讨弥漫性特发性骨质增生症（diffuse idiopathic skeletal hyperostosis，DISH）伴腰椎管狭窄症的影像学特征。方法：回顾性分析2017年6月~2021年10月在我院手术治疗的96例DISH合并L4/5椎管狭窄症患者的术前影像学资料，男58例，女38例；年龄51～77岁（65.9±6.1岁）；将骨化仅限于胸椎节段的患者纳入T-DISH组（n=49），骨化累及胸椎和腰椎节段的患者纳入L-DISH组（n=47）；选取同期在我院手术治疗的性别、年龄及狭窄节段相匹配的无DISH的腰椎管狭窄症患者作为对照组（N-DISH组，n=125）。测量各组术前胸椎后凸角（thoracic kyphosis，TK）、腰椎前凸角（lumbar lordosis，LL）、骶骨倾斜角（sacral slope，SS）、骨盆入射角（pelvic incidence，PI）、骨盆倾斜角（pelvic tilt，PT）和矢状位平衡距离（sagittal vertical axis，SVA），计数骨化韧带节段数目，按照Pfirrmann分级和Weishaupt分级分别评估椎间盘与小关节的退变情况，并测量L4/5节段椎间隙高度、椎管前后径、椎管横截面积、硬膜囊面积、小关节间距和黄韧带厚度等。比较三组在矢状位形态、椎间盘与小关节退变情况及椎管狭窄特征等方面的差异，并对所有患者骨化韧带节段数目、硬膜囊面积、椎管横截面积、椎间盘退变Pfirrmann分级及小关节退变Weishaupt分级之间行相关性分析。结果：DISH组SVA和TK显著性大于N-DISH组（P＜0.05），其中L-DISH组SVA显著性大于N-DISH组（P＜0.05），而T-DISH组与N-DISH组SVA差异无统计学意义（P>0.05）。DISH组与N-DISH组的LL、SS、PI及PT无统计学差异（P>0.05），但L-DISH的LL及SS显著性小于N-DISH组（P＜0.05）；L-DISH组的LL和SS显著性小于T-DISH组（P＜0.05），两组间SVA、TK、PI和PT无统计学差异（P>0.05）。DISH组椎间盘和小关节退变分级均高于N-DISH组，差异有统计学意义（P＜0.001）；L-DISH组椎间盘退变Pfirrmann分级显著性高于T-DISH组（P＜0.001），而小关节退变Weishaupt分级无统计学差异（P=0.08）。N-DISH组患者L4/5节段椎间隙高度、椎管前后径、椎管横截面积、小关节间距和黄韧带厚度与DISH组比较无显著性差异（P>0.05），硬膜囊面积显著性大于DISH组（P＜0.05）；T-DISH组与L-DISH组比较均无统计学差异（P>0.05）。相关性分析显示，骨化韧带节段数目与椎间盘退变Pfirrmann分级呈中度正相关（r=0.440，P＜0.001），与小关节退变Weishaupt分级呈强正相关（r=0.661，P＜0.001）；硬膜囊面积与椎间盘退变Pfirrmann分级无显著相关性，与小关节退变Weishaupt分级呈负相关（r=－0.323，P＜0.001）；椎管横截面积与椎间盘退变Pfirrmann分级和小关节退变Weishaupt分级均无显著相关性（P>0.05）；椎间盘退变Pfirrmann分级与小关节退变Weishaupt分级有显著相关性（P＜0.001）。结论：DISH患者脊柱异位骨化累及腰椎可明显改变脊柱矢状位形态，致使躯干出现前倾、腰椎前凸减小及SS丢失等。DISH患者存在明显的椎间盘和小关节退变，且椎管狭窄程度较为严重。

英文摘要:

  【Abstract】 Objectives: To investigate the imaging features of lumbar spinal stenosis(LSS) in patients with diffuse idiopathic skeletal hyperostosis(DISH). Methods: The preoperative imaging data of 96 DISH patients complicated with LSS at L4/5 who underwent operation in our hospital from June 2017 to October 2021 were retrospectively reviewed. The patients were divided into T-DISH group(n=49) with ossification limited only to thoracic vertebrae and L-DISH group(n=47) with ossification involving thoracic and lumbar vertebrae; And LSS patients without DISH treated surgically in our hospital during the same period were recruited as control, the N-DISH group(n=125), by matching gender, age, and stenosis segments. The thoracic kyphosis(TK), lumbar lordosis(LL), sacral slope(SS), pelvic incidence(PI), pelvic tilt(PT), and sagittal vertical axis(SVA) were measured of all groups of patients, the numbers of ossified ligament were counted, and the degenerative conditions of intervertebral disc and facet joint were evaluated with Pfirrmann grade and Weishaupt grade respectively. Additionally, the anteroposterior diameter, cross-sectional area, and dural sac area of L4/5 vertebral canal were measured to evaluate spinal stenosis. The differences in sagittal morphology, intervertebral disc and facet joint degeneration, and spinal canal stenosis were compared between the three groups, and correlation analyses between the number of ossified ligament segments, dural sac area, cross-sectional area of the spinal canal, Pfirrmann grade of intervertebral disc degeneration, and Weishaupt grade of facet joint degeneration were performed. Results: SVA and TK in DISH group were significantly higher than those in N-DISH group(P<0.05), and SVA in L-DISH group was significantly higher than that in N-DISH group, while no significant difference of SVA was found between T-DISH group and N-DISH group. Although there was no significant difference in LL, SS, PI and PT between DISH group and N-DISH group, LL and SS of L-DISH group were significantly lower than those of N-DISH group(P<0.05). LL and SS in L-DISH group were significantly smaller than those in T-DISH group, but there was no significant difference in SVA, TK, PI and PT between groups. The degeneration grades of disc and facet joint in DISH group were higher than those in N-DISH group with significant differences(P<0.001); The Pfirrmann grade of disc degeneration in L-DISH group was significantly higher than that in T-DISH group(P<0.001), while there was no significant difference in Weishaupt grade of facet joint degeneration between groups(P=0.08). N-DISH group wasn′t different significantly from DISH group in the anteroposterior diameter of spinal canal at L4/5, and was significantly larger in the dural sac area. Correlation analyses showed that the number of ossified ligament segments was moderately positively correlated with Pfirrmann grade of disc degeneration(r=0.440, P<0.001), while strongly positively correlated with Weishaupt grade of small joint degeneration(r=0.661, P<0.001); Dural sac area wasn′t significantly correlated with Pfirrmann grade of disc degeneration, and it was negatively correlated with Weishaupt grade of small joint degeneration(r=-0.323, P<0.001); Cross-sectional area of spinal canal wasn′t significantly correlated with Pfirrmann grade of disc degeneration or Weishaupt grade of small joint degeneration(P>0.05); And Pfirrmann grade of disc degeneration was significantly correlated with Weishaupt grade of small joint degeneration(P<0.001). Conclusions: Heterotopic ossification of the spine affecting the lumbar in DISH patients can significantly change the sagittal morphology, resulting in trunk anteversion, reduced LL, and loss of SS. DISH patients have obvious degeneration of intervertebral disc and facet joint and serious spinal stenosis.