Pseudocystic degeneration of the lumbar ligamentum flavum: a little known entity

OBJECTIVE: The objective of this work was to investigate the clinical and histologic features of patients with pseudocystic lesions of the ligamentum flavum in the lumbar region of the spinal canal and ascertain the existence of genuine ligamentum flavum pseudocysts. METHODS: Retrospective chart and histologic study of a patient cohort with lumbar radiculopathy due to a cystic intraspinal lesion and who had undergone decompressive surgery was conducted. Intraoperatively, the stenosing process had been found to be different from common etiologic entities and had been submitted for histologic examination. RESULTS: The 33 patients with symptoms and signs of lumbar radiculopathy were between 48 and 85 years of age (mean 63.5 years). Twenty (61%) of them were women. All patients showed degenerative changes of the bony structures of the spine by conventional radiography. Segmental instability due to degeneration of the lumbar spine was present in 45%. Computed tomography and/or magnetic resonance imaging showed a cystic lesion. Clinical and histologic examination confirmed their origin from within the severely degenerated ligamentum flavum. CONCLUSIONS: Radiologic, surgical, and histologic findings suggest that the pseudocystic degeneration of the ligamentum flavum represents a genuine entity that is associated with degenerative changes of the structures of the respective lumbar spine segment. These pseudocystic lesions may compress the adjacent nerve roots, provoking symptoms and signs of radiculopathy. The findings suggest that the surgical treatment not only must consist of removal of the pseudocyst but must also include a radical extirpation of the ligamentum flavum surrounding the pseudocyst to avoid recurrence of such a lesion.     

单纯黄韧带肥厚致腰椎管狭窄及根性疼痛

目的：探讨单纯黄韧带肥厚致腰椎管狭窄及根性疼痛的临床表现。方法：回顾1997年－2001年腰腿痛的143例病例，其中例为单纯黄韧带肥厚所致，年龄65－78岁，均手术行单纯黄韧带切除，达到椎管减压，结果：此类患者均为老年，病程长，可有急性加重过程，疼痛可与椎间盘突出相似，但以下腰疼痛明显，而下肢放射痛相对较轻，临床及影像学均易误诊。结论：退变引起的黄韧带肥厚可造成椎管狭窄及根性疼痛，手术切除后症状明显缓解。长期随访，患者腰痛消失，可以长时间行走，明显提高了生活质量。     

腰椎管单开门成形术治疗腰椎管狭窄症40例

作者报告采用腰椎管单开门成形术治疗腰椎管狭窄症．1993年4月～1996年4月手术40例，平均49岁，病史2～5年，平均3．2年。40例经长期系统保守治疗正疗程以上．均经X线平片、CT和／或脊髓造影检查。术中见骨性及发育性30例，肿瘤性4例，炎症性2例．其他4例。术后卧床1月。随访3月～36月，优26例，良12例，可2例。该术式可扩大骨性椎管容积；同时切除增生黄韧带、小关节突及突出的髓核．直接解除压迫；可探查同侧各神经根管；能保持后柱结构大部完整，操作简单。可作为一种探查减压术式。     

腰椎狭窄软性椎管的应力改变分析

目的 探讨腰椎软性椎管改变与椎管狭窄的关系。方法 在本研究52例中分为椎管狭窄组和对照组，2003年1月至2007年12月，推管狭窄组从因腰椎管狭窄病行后路椎板减压术的患者中取黄韧带标本对照组黄韧带标本共为10例，取自青年腰椎骨折行后路椎板减压术患者，后纵韧带标本共4例取自腰椎爆裂骨折前路椎体减压术患者。分别观察两组标本切片镜下的表现并加以分析。结果 在腰椎管狭窄病组，黄韧带及后纵韧带镜下表现为纤维肥大，基质内可见脂肪及小囊肿；对照组则表现为纤维细胞排列规则、无纤维化表现。结论 腰椎管软性椎管的应力改变及退行性变，是导致腰椎管狭窄的一个因素。     

The narrowing of the lumbar spinal canal during loaded MRI: the effects of the disc and ligamentum flavum

Load and activity changes of the spine typically cause symptoms of nerve root compression in subjects with spinal stenosis. Protrusion of the intervertebral disc has been regarded as the main cause of the compression. The objective was to determine the changes in the size of the lumbar spinal canal and especially those caused by the ligamentum flavum and the disc during loaded MRI. For this purpose an interventional clinical study on consecutive patients was made. The lumbar spines in 24 supine patients were examined with MRI: first without any external load and then with an axial load corresponding to half the body weight. The effect of the load was determined through the cross-sectional areas of the spinal canal and the ligamentum flavum, the thickness of ligamentum flavum, the posterior bulge of the disc and the intervertebral angle. External load decreased the size of the spinal canal. Bulging of the ligamentum flavum contributed to between 50 and 85% of the spinal canal narrowing. It was concluded that the ligamentum flavum, not the disc had a dominating role for the load induced narrowing of the lumbar spinal canal, a finding that can improve the understanding of the patho-physiology in spinal stenosis.     

Two-level ligamentum flavum hematoma in the lumbar spine. Case report

Ligamentum flavum hematoma is a rare cause of spinal root or cord compression that usually occurs at a single level. No case of multiple-level ligamentum flavum hematoma has previously been reported. We report an extremely rare case of double, contiguous ligamentum flavum hematomas in the lumbar spine. A 71-year-old man with hypertension and degenerative lumbar scoliosis presented with pain and muscle weakness in the left lower extremity after physical exertion. Magnetic resonance imaging of the lumbar spine showed severe spinal stenosis caused by two-level ligamentum flavum hematoma (L3-L4 and L4-L5). Both hematomas were completely removed and the diagnosis was histologically confirmed. Symptoms completely resolved after surgery. Despite being extremely rare, ligamentum flavum hematoma with involvement of multiple levels may be observed.     

中央型腰椎管狭窄症患者黄韧带组织生化成分变化的研究

目的:通过测定中央型腰椎管狭窄症患者腰椎黄韧带胶原蛋白和蛋白多糖含量变化,观察组织显微结构改变,探讨黄韧带组织生化成分改变与中央型腰椎管狭窄症发病的相关性方法:收集中央型腰椎管狭窄症患者的腰椎黄韧带65块作为退变组,正常腰椎黄韧带27块作为对照组,采用微量羟脯氨酸测定法和硫酸-咔唑法分别测定两组黄韧带中羟脯氨酸及糖醛酸吸光度,并计算胶原蛋白和蛋白多糖含量;游标卡尺测量黄韧带厚度;并行HE染色和Masson染色,显微镜下观察各组组织结构改变。结果:退变组黄韧带厚度、胶原蛋白及蛋白多糖含量均高于对照组,差异有显著性(P0.05);病理学观察退变黄韧带弹性纤维排列紊乱,数量减少,胶原纤维增生。结论:退变腰椎黄韧带中胶原蛋白和蛋白多糖含量增加,黄韧带生化成分改变可能引起黄韧带厚度增加,参与中央型腰椎管狭窄症的发生。     

Cryomicrotomy of the lumbar spine

To investigate the pathogenesis of lumbar canal stenosis, a morphologic study was carried out by cryomicrotomy using 10 fresh lumbar spine specimens from the 3rd lumbar vertebra to the 1st sacral vertebra. The cryomicrotomy findings confirmed that anatomical relations were clearly demonstrated between dura, nerve root, osseous structure, disc and ligamentum flavum in frontal, sagittal, and transverse section. Furthermore, in sagittal section specimens, thickness of ligamentum flavum varies from extension to flexion. These conditions play a dynamic factor in the pathogenesis of spinal canal stenosis.     

全椎板截骨再植椎管扩大成形术治疗胸椎黄韧带骨化症

目的总结胸椎黄韧带骨化症导致胸椎椎管狭窄的影像学特点，探讨改良椎管减压术的临床疗效。方法胸椎黄韧带骨化症31例，男18例，女13例；年龄26—73岁，平均45．7岁。术前均行MR、CT检查以明确诊断。合并颈椎管狭窄3例、腰椎管狭窄5例，颈胸腰椎管狭窄同时存在者2例；合并胸椎后纵韧带骨化和椎间盘突出症9例。单节段3例，双节段12例，三节段11例，四节段以上5例。局限型6例，连续型17例，跳跃型8例。共94个病变节段，其中上胸段(T1～T4)23个节段、中胸段(T5～T8)19个节段、下胸段(T9-T12)52个节段。手术采用全椎板截骨原位再植椎管扩大成形术。对9例合并胸椎后纵韧带骨化和椎间盘突出者，在后方减压的同时，行切除椎管前方突出椎间盘的环脊髓减压及后路钉棒系统内固定。术后疗效评价参照Epstein标准。结果24例患者随访6—63个月，平均15个月。术后疗效优14例、良7例、可3例，优良率87．5％。1例因术后停用脱水药物过早引起下肢瘫痪症状加重；2例出现下肢静脉血栓；2例硬脊膜撕裂。结论MR结合CT检查是诊断胸椎黄韧带骨化症最有效的手段，全椎板截骨再植椎管扩大成形术安全可靠，疗效满意。     

退行性变黄韧带细胞的体外培养及初步鉴定

目的：探讨黄韧带退变的发生机理。方法：采用组织块培养法，体外培养正常黄韧带和退变性黄韧带细胞．并进行细胞化学、免疫细胞化学等方面研究。结果：黄韧带细胞可以在体外增殖和传代，退变性黄韧带细胞呈现出某些成骨细胞表型特征，而正常黄韧带细胞主要为成纤维细胞表型。结论：退变黄韧带中存在大量具备某些成骨细胞表型特征的细胞，其中包括软骨细胞，它们可能被骨形成蛋白等骨生长因子所调控。     

颈椎管狭窄症患者黄韧带肥厚的组织学研究及临床意义

目的：探讨颈椎管狭窄症患者黄韧带肥厚的组织学变化及其临床意义。方法：对68例颈椎管狭窄症患者肥厚的黄韧带进行组织学及免疫组化染色研究。结果：58例（85．3％）肥厚的黄韧带内有血管增生及大量炎细胞浸润；其免疫组化染色KP—1均为阳性，49例LCA染色阳性。10例（14．7％）肥厚的黄韧带组织内未见炎细胞浸润，其免疫组化染色KP—1及LCA染色均阴性。11例（16．2％）肥厚黄韧带中发现了钙化或骨化灶。本组9例术前影像学显永不稳定节段的肥厚黄韧带内均发现了炎症反应。结论：颈椎管狭窄症患者黄韧带肥厚的原因之一可能是组织中出现了慢性炎症反应；颈椎不稳定可能是造成黄韧带内炎症反应的原因之一。     

合并腰椎疾患的下胸椎黄韧带骨化临床诊治

目的探讨合并腰椎疾患的下胸椎黄韧带骨化临床特点及诊治方法。方法下胸椎黄韧带骨化同时存在腰椎疾患的患者23例,诊断结合X线、椎管造影、CT、MRI检查,体征以肌张力增高和深反射异常为特点;患者均采用病变节段全椎板减压手术治疗。结果23例均获随访,时间10-36个月,手术减压1-3节胸椎椎板,患者在末次随访时都有不同程度的神经功能改善。术后功能恢复优4例,良13例,可6例。术后到末次随访时无一例患者因腰椎疾病而再次接受手术。结论合并腰椎疾患的下胸椎黄韧带骨化需要注意将客观体征与多种影像学检查相结合,尽早诊断、早期手术。     

颈椎黄韧带叠压症

目的：研究颈椎黄韧带叠压对脊髓压迫和影响。方法：对1994年以来,经后路颈椎管扩大成形术后随访的67例黄韧带叠压症,进行影像学、病理学和临床观察。结果：切除黄韧带、椎管扩大成形术后67例临床症状显著改善,优良率91％。结论：长期屈颈位工作和颈椎间盘等退变,使黄韧带过长、变韧、骨化,尤于颈椎过伸时,引起黄韧带叠压颈脊髓,是本症出现临床症状体征的原因。     

Characterization of cultured human ligamentum flavum cells in lumbar spine stenosis.

To investigate the pathogenesis of the degenerative changes of the ligamentum flavum occurring in lumbar spine stenosis, yellow ligament cells from patients with lumbar spine stenosis were cultured for the first time and subjected to biochemical, histochemical and immunohistochemical study. Stenotic ligamentum flavum (SLF) cells were seen to express high levels of alkaline phosphatase (ALP) activity and to produce a matrix rich in type I and III collagen, fibronectin and osteonectin. The matrix mineralized only following beta-glycerophosphate (betaGP) and ascorbic acid supplementation. Stimulation with human parathyroid hormone (PTH) increased intracellular cAMP concentration. These findings indicate that there was significant evidence of osteoblast-like activity in these cells. SLF cells also stained for S100 protein, type II and type X collagen, and co-localized type II collagen and ALP labelling, reflecting the presence of hypertrophic chondrocyte-like cells. Cultures from control patients showed neither osteoblastic nor chondrocytic features: they expressed type I and type III collagen and fibronectin, but did not stain for osteonectin, nor were bone-like calcifications observed in presence or absence of betaGP. Normal ligamentum flavum (NLF) cells did not synthesized S100 protein or type II or type X collagen, and showed a weaker response to PTH stimulation. Our data demonstrated the presence of hypertrophic chondrocytes with an osteoblast-like activity in the ligamentum flavum of patients with spinal stenosis suggesting that they could have a role in the pathophysiology of the heterotopic ossification of ligamentum flavum (OLF) in lumbar spine stenosis.     

Quantitative analysis of transforming growth factor-beta 1 in ligamentum flavum of lumbar spinal stenosis and disc herniation.

STUDY DESIGN: The concentration of transforming growth factor-beta 1 (TGF-beta1) was examined in the ligamentum flavum of lumbar spinal stenosis and disc herniation. OBJECTIVE: To investigate the role of TGF-beta1 on hypertrophy of the ligamentum flavum in lumbar spinal stenosis compared with that of lumbar disc herniation. SUMMARY OF BACKGROUND DATA: The hypertrophy of the ligamentum flavum is known to be related to degenerative changes that are secondary to the aging process or mechanical instability. However, there has been no study to investigate the effect of biochemical factors, such as growth factors, associated with hypertrophy of the ligamentum flavum. METHODS: The concentrations of TGF-beta1 were analyzed in the surgically obtained ligamentum flavum specimens from lumbar spinal stenosis (n = 10; mean age 62.8 years) and disc herniation (n = 10; mean age 35.6 years) by enzyme-linked immunosorbent assay. The localization of TGF-beta1 within the ligamentum flavum was determined using immunohistochemical study. The thickness of the ligamentum flavum was measured with axial T1-weighted magnetic resonance imaging. The biochemical and radiologic results were compared for these two conditions. RESULTS: The mean concentration of TGF-beta1 was 123.78 pg/100 microg protein (range 11-374 pg/100 microg protein) in lumbar spinal stenosis and 38.56 pg/100 microg protein (range 0-155 pg/100 microg protein) in lumbar disc herniation; the difference between lumbar spinal stenosis and disc herniation was statistically significant (P = 0.029). The mean thickness of the ligamentum flavum was 4.44 mm (range 3.4-5.4 mm) in lumbar spinal stenosis and 2.44 mm (range 1.8-4.0 mm) in lumbar disc herniation; the difference between lumbar spinal stenosis and disc herniation was statistically significant (P = 0.001). On immunohistochemical study TGF-beta1 was positively stained on the fibroblasts within the ligamentum flavum specimens. CONCLUSION: The current results suggest that higher expression of TGF-beta1 by fibroblasts might be related to the development of hypertrophy of the ligamentum flavum in lumbar spinal stenosis.     

Mechanical stretching force promotes collagen synthesis by cultured cells from human ligamentum flavum via transforming growth factor-beta1.

Although mechanical stress as a result of spinal instability is known to cause hypertrophy of the ligamentum flavum resulting in degenerative spinal canal stenosis, the mechanism of the ligament hypertrophy is not well understood. In the present study, we investigated the effect of mechanical stretching force on collagen synthesis and transforming growth factor-beta1 (TGF-beta1) production using ligament cells isolated from human ligamentum flavum in vitro. Ligamentum flavum cells (LFCs) were isolated from human ligamentum flavum obtained from patients who underwent lumbar spine surgery. The LFCs were subjected to a mechanical stretching force using a commercially available stretching device that physically deformed the cells. Collagen synthesis and TGF-beta1 production levels in the LFCs were then examined. Notable increases were observed in the gene expressions of collagen types I, III, and V in LFCs subjected to mechanical stretching force. The increase in collagen gene expression of LFCs was inhibited in the presence of anti-TGF-beta1 antibodies. Production of TGF-beta1 by the LFCs also increased significantly by the mechanical stretching force. Exogenous application of TGF-beta1 was confirmed to increase collagen synthesis of the LFCs. This data indicated that mechanical stretching force can promote TGF-beta1 production by LFCs, resulting in hypertrophy of the ligament.     

Ligamentum flavum hematoma in the rigid thoracic spinal segments: case report

Ligamentum flavum hematoma, a rare cause of spinal nerve root and canal compression, typically occurs in the mobile lumbar spine segments. A thoracic ligamentum flavum hematoma is extremely rare--only one such case of a thoracolumbar (T11-12) lesion has been reported. The thoracolumbar region with its floating ribs, however, is structurally and biomechanically similar to the lumbar spine and its mobility is greater than the higher thoracic levels. To the best of their knowledge, the authors report the first case of a ligamentum flavum hematoma in the region of the rigid thoracic spinal segments with the contiguous rib cage. A symptomatic T9-10 ligamentum flavum hematoma is described in the case of a 66-year-old woman with compensatory thoracic lordosis secondary to the lumbar degenerative kyphosis. The hematoma was removed and the diagnosis was histologically confirmed. The authors speculate that thoracic lordosis might have contributed to the development of the hematoma because the ligamentum flavum and the facet joint were subjected to greater axial stress than in individuals with normal spinal alignment.     

Ligamentum flavum hematoma in the lumbar spine

A previously healthy 45-year-old woman presented with ligamentum flavum hematoma manifesting as radicular leg pain. Neurological examination findings were consistent with L-5 root compression. An old hematoma inside the degenerated ligamentum flavum was drained. The cyst showed no connection to the facet joint. Complete resection of the mass was performed, resulting in excellent pain relief. The most common cystic lesion in the lumbar spine is synovial cyst associated with the facet joints, but ligamentum flavum hematoma should be included in the differential diagnosis. The preoperative diagnosis can be based on computed tomography and magnetic resonance imaging findings of degenerative thickening of the ligamentum flavum associated with a fluid component.     

Management of cervical and lumbar stenosis]

Spinal stenosis is most common in elderly patients and is defined as narrowing of the spinal canal and (or) lateral nerve root canals. The underlying processes leading to spinal stenosis are degenerative changes in facet joints and intervertebral discs and buckling of the ligamentum flavum. Spinal stenosis can occur in both the cervical and the lumbar spine. Cervical stenosis mayleat to the development of radiculopathy and (or) myelopathy. The majority of patients respond to nonoperative management. Degenerative lumbar spinal stenosis presents with back and (or) leg paints of valuing severity and duration. Nonoperative treatment associated with lumbar spinal stenosis consists of restituting and avoiding those maneuvers that reproduce pain. Surgical treatment of cervical and lumbar stenosis includes decompressive lamine ctomy, often fusion and instrumentation.     

临床论腰椎管狭窄症狭窄因素分类及临床应用

目的:探讨腰椎管狭窄症CT影像学分类方法,为手术减压部位及术式选择提供依据。方法:把腰椎管管壁致狭窄病变的组织分为关节突(A)、椎体与椎弓骨性组织(B)、钙化结缔组织(C)、椎间盘(D)、硬膜外瘢痕(E)和黄韧带(F)六个类别,把椎管分为前壁(1)、侧壁(2)、后壁(3)三个区。通过对43例共70个节段腰椎管狭窄症的CT影像学病因诊断,用字母-数字化代码对椎管管壁狭窄因素进行分类,根据不同狭窄因素行个体化治疗。结果:共统计出12类椎管管壁狭窄因素。43例中40例得到定期随访,随访1~5年,优良率90.0%。结论:腰椎管狭窄症管壁狭窄因素分类方法可表达椎管狭窄的性质、部位,有助于术前减压目标的确定、术式选择和电脑信息化处理。