Corpectomy for multi-level cervical spondylosis and ossification of the posterior longitudinal ligament

The choice of a surgical approach for multi-level cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL) is still a controversial issue. While most of the surgeons are still performing decompression by laminectomy some are doing multi-level anterior decompression. Few neurosurgeons are performing decompression by corpectomy. We have treated 26 patients by median cervical corpectomy during the last 4 years. These patients were followed up for a mean period of 25 months. Twenty one (80%) patients had a good outcome, 2 patients remained unchanged and 3 expired. Review of the literature and our experience indicates that patients with CSM and OPLL should be operated by median cervical corpectomy (anterior approach).     

Familial ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine: case report

BACKGROUND

Ossification of the posterior longitudinal ligament (OPLL) of the spine is most common in the Japanese population and in the cervical spine. We present a case of OPLL of the lower thoracic spine in two Caucasian siblings.

CASE DESCRIPTION

A 58-year-old female presented with lower extremity dysesthesia and urinary hesitancy. Family history was significant for a brother who had OPLL of the lower thoracic spine removed surgically. Magnetic resonance imaging and computed tomography scan of the thoracic spine demonstrated OPLL at T10–11 causing cord compression and abnormally high T2 signal in the cord. The patient underwent posterior decompression with improvement of her symptoms.

CONCLUSION

A genetic predisposition to develop OPLL has been suggested by previous linkage and biochemical studies. While OPLL is an increasingly recognized diagnosis in North America, this is the first reported case of familial thoracic OPLL in Caucasian siblings.     

Cervical ossification of the posterior longitudinal ligament: factors affecting the effect of posterior decompression

Objective: Decompression procedures for cervical myelopathy of ossification of the posterior longitudinal ligament (OPLL) are anterior decompression with fusion, laminoplasty, and posterior decompression with fusion. Preoperative and postoperative stress analyses were performed for compression from hill-shaped cervical OPLL using 3-dimensional finite element method (FEM) spinal cord models.

Methods: Three FEM models of vertebral arch, OPLL, and spinal cord were used to develop preoperative compression models of the spinal cord to which 10%, 20%, and 30% compression was applied; a posterior compression with fusion model of the posteriorly shifted vertebral arch; an advanced kyphosis model following posterior decompression with the spinal cord stretched in the kyphotic direction; and a combined model of advanced kyphosis following posterior decompression and intervertebral mobility. The combined model had discontinuity in the middle of OPLL, assuming the presence of residual intervertebral mobility at the level of maximum cord compression, and the spinal cord was mobile according to flexion of vertebral bodies by 5°, 10°, and 15°.

Results: In the preoperative compression model, intraspinal stress increased as compression increased. In the posterior decompression with fusion model, intraspinal stress decreased, but partially persisted under 30% compression. In the advanced kyphosis model, intraspinal stress increased again. As anterior compression was higher, the stress increased more. In the advanced kyphosis +?intervertebral mobility model, intraspinal stress increased more than in the only advanced kyphosis model following decompression. Intraspinal stress increased more as intervertebral mobility increased.

Conclusion: In high residual compression or instability after posterior decompression, anterior decompression with fusion or posterior decompression with instrumented fusion should be considered.     

选择性融合联合单开门椎管扩大椎板成形术治疗局部不稳的颈椎后纵韧带骨化症的疗效

目的:比较三种颈椎后路术式治疗存在局部不稳的颈椎后纵韧带骨化症(ossification of the posterior longitudinal ligament,OPLL)患者的临床疗效,探讨选择性融合联合单开门椎管扩大椎板成形术的临床应用价值。方法:回顾分析我院2014年6月~2017年6月收治的存在局部不稳的颈椎OPLL患者107例,其中男性61例,女性46例;年龄68.1±10.2岁(33~84岁),随访时间2.1±1.3年(0.5~3.5年)。所有患者证实存在OPLL及颈椎局部不稳,且存在颈脊髓压迫相关症状体征,其中38例行单纯颈后路单开门椎管扩大椎板成形术(A组),35例行选择性融合联合单开门椎管扩大椎板成形术(B组),34例行传统颈后路椎板切除固定术式(C组)。分别于术前、术后2d及末次随访时采用日本矫形外科学会(Japanese Orthopaedic Association,JOA)评分并计算Hirabayashi改善率,对患者的神经功能情况进行评估;拍摄颈椎正侧位及过屈过伸位X线片测量颈椎的曲度(C2-7 Cobb角)、颈椎整体活动度(C2-7 range of motion,C2-7 ROM)和颈椎不稳节段的活动度,统计内固定相关并发症。通过颈椎MRI评估患者颈髓高信号的情况并计算高信号强度比值(high signal intensity ratio,HSIR)。比较三组患者颈椎整体活动度和不稳节段的活动度,比较存在颈髓高信号患者的术前、术后HSIR及三组之间的差异。结果:三组患者均取得了满意的神经功能改善,末次随访时JOA评分分别为14.93±3.18分、15.22±2.79分和14.72±3.02分,Hirabayashi改善率分别为(66.35±13.48)%、(70.06±14.14)%和(64.14±18.05)%。三组患者术前颈椎曲度分别为7.43°±3.69°、7.66°±2.99°、6.96°±4.38°,组间比较无统计学差异(F=13.19,P=0.071),末次随访时颈椎曲度与术前相比基本一致(5.58°±4.26°、5.73°±3.81°、5.49°±4.33°),随访期间未发现颈椎曲度明显改变、后凸等情况。随访期间未出现内固定相关并发症。末次随访时A、B两组患者颈椎整体活动度(C2-7 ROM)无统计学差异(17.63°±8.31°和18.72°±9.52°,P=0.089),C组患者末次随访颈椎整体活动度明显差于A、B两组患者(3.90°±7.74°vs 17.6°±8.3°,P=0.012;3.90°±7.74°和18.72°±9.52°,P=0.003);B组、C组患者术后颈椎不稳节段活动度明显降低,末次随访时已完全融合。共有71例(71.03%)患者出现颈椎MRI T2加权高信号表现,存在高信号的节段与存在不稳的节段一致。三组患者HSIR值末次随访时均较术前明显降低(1.33±0.18 vs 1.68±0.11,1.12±0.12 vs 1.71±0.14和1.20±0.33 vs 1.65±0.18,P=0.001),但与A组患者相比,B组和C组患者的降低程度均较显著,差异存在统计学意义(P<0.05)。结论:选择性融合联合单开门椎管扩大椎板成形术是治疗存在局部不稳的颈椎OPLL患者的有效方法,可以在广泛减压颈脊髓压迫的同时增加颈椎的节段稳定性,同时保留颈椎一定的活动度、减少术后轴性症状发生。     

颈椎病合并颈椎后纵韧带骨化症的前路手术治疗

目的 探讨颈椎病合并颈椎后纵韧带骨化症(OPLL)前路切除减压的方法及其临床效果.方法采用颈椎前路减压治疗颈椎病合并颈椎OPLL患者61例,其中男42例,女19例,平均57岁(45～74岁).术前明确诊断颈椎病合并OPLL者49例,术中发现合并有OPLL者12例.OPLL椎管狭窄率32%～70%,平均52%.神经功能JOA评分术前4～14分,平均9.6分.手术在常规颈前路经椎间隙或椎体次全切除减压的基础上,切除骨化后纵韧带彻底减压.结果 本组41例患者采用前路椎体次全切除减压,6例经椎间隙扩大减压,14例采用椎体次全切除结合经椎间隙减压的手术方式.所有患者随访6个月～3年,平均16个月.术后JOA评分8～16分,平均12.8分,神经功能恢复率25.0%～87.5%,平均65.2%.5例患者术后并发脑脊液漏,经保守治疗后均获得痊愈,无1例出现脊髓功能损害加重.结论 颈椎病合并颈椎OPLL增加了手术难度和风险,在颈椎前路常规减压的基础上再将骨化的后纵韧带切除,保证了前路减压的彻底性,可提高手术治疗效果.     

前后路手术与单纯前路或后路手术治疗颈椎孤立型后纵韧带骨化症的比较研究

目的:比较前、后路及前后路一期手术治疗颈椎孤立型后纵韧带骨化症的疗效及术中并发症的发生率。方法:回顾性分析2000年6月～2009年6月收治的69例诊断为颈椎孤立型后纵韧带骨化症并行手术治疗患者的临床资料。患者均有四肢肌力降低,双下肢行走不稳,双上肢精细动作功能减退,双下肢肌张力高,膝腱反射亢进,双侧Hoffman′s征阳性等锥体束受损的症状及体征,且颈椎CT及MRI检查均显示为孤立型后纵韧带骨化。根据手术方式不同将所有患者分成3组:Ⅰ组25例,行单纯颈前路减压椎间融合内固定术,术中从前路减压,切除骨化的后纵韧带;Ⅱ组22例,行单纯颈后路单开门椎管扩大成形术;Ⅲ组22例,行一期颈椎前后路联合手术(先行颈后路单开门椎管扩大成形术,然后再行前路减压内固定术)。比较硬脊膜破损发生率及双下肢无力的发生率,应用日本骨科学会(JOA)评分标准评价术后3组患者的JOA评分改善率。结果:Ⅰ、Ⅱ、Ⅲ组的术中硬脊膜破损率分别为32%、0、4.5%,术后双下肢无力的发生率分别为24%、0、0,Ⅲ组明显低于Ⅰ组(P<0.05)。所有病例均获得至少1年的随访,随访时间平均15.3个月。术后3个月时,Ⅰ、Ⅱ、Ⅲ组的JOA评分改善率分别为(40.0±3.4)%、(32.3±4.5)%和(44.6±5.4)%;末次随访时分别为(60.8±7.7)%、(52.6±12.1)%和(66.2±8.9)%,Ⅲ组的JOA评分改善率均明显高于Ⅰ组及Ⅱ组(P<0.05)。结论:治疗颈椎孤立型后纵韧带骨化症,行一期前后路联合手术近期疗效优于单纯颈前路及颈后路手术,且并发症发生率较低。     

Two-staged decompression for thoracic paraparesis due to the combined ossification of the posterior longitudinal ligament and the ligamentum flavum: a case report

Study design A case report of ossification of the posterior longitudinal ligament (OPLL) combined with ossification of the ligamentum flavum, or yellow ligament (OYL), in the upper thoracic spine. Objective To describe a rare clinical entity and its management pitfalls in a patient with upper thoracic myelopathy due to combined OPLL and OYL. Methods A 52-year-old woman developed paresthesia and paraparesis of both legs. One month prior to admission she fell and became unable to walk. She was diagnosed as having upper thoracic myelopathy due to combined OPLL and OYL and was treated by two-stage anterior and posterior spinal decompression. Posterior decompression was achieved first by laminoplasty at C3–Th1 and laminectomy of Th2 and Th3. Results After posterior decompression, her symptoms immediately and dramatically improved. However, symptoms recurred after she was able to achieve a sitting or standing position. We then performed anterior decompression at Th2, which again improved her symptoms. At two years post-surgery, she is ambulatory with the use of a cane. Conclusion Upper thoracic myelopathy due to OPLL and OYL was treated by combined 2-staged anterior and posterior decompression. In this case, posterior decompression alone was inadequate to relieve the symptoms of this pathological condition.     

Histomorphometric study of iliac bones in cervical myelopathy with ossification of the posterior longitudinal ligament

To investigate whether there was any abnormal systemic bone metabolism in patients with ossification of the posterior longitudinal ligament (OPLL), we measured various histomorphometric indices of the iliac trabecular bones in 19 patients with OPLL (14 men, 5 women). For each index, the Z-score for each patient was calculated, using the SD and mean value for non-OPLL control group (n = 159) who underwent orthopaedic surgeries and had no systemic disease, age-matched for each decade. A Z-score of 1.0 meant that the observed data deviated 1 SD from the normal average, and a distribution from −2 to +2 was considered normal. All the averaged Z-scores were within ±1.0 and there were no significant differences between the OPLL and the control groups. There was also no difference in Z-score among three types of OPLL (segmental, continuous, and mixed). From these results, we concluded that there was no common abnormal bone metabolism affecting the bone histomorphometry of the iliac bone in OPLL patients. However, in two patients, the Z-score for bone volume (BV/TV) was more than 2.0, with increased osteoid volume (OV/TV) and increased trabecular thickness, suggesting that there was some abnormal bone metabolism in these two patients with OPLL. Received for publication on Aug. 11, 1997; accepted on May 28, 1998     

后纵韧带钩辅助下颈椎后纵韧带骨化物切除减压术

目的探讨后纵韧带钩辅助下颈椎后纵韧带骨化物前路切除的适应证、方法及其临床效果。方法患者19例,男14例,女5例;年龄51-71岁,平均59岁。术前影像学检查结果示后纵韧带骨化物局限型6例,分节型13例;椎管狭窄率32％-75％,平均54％。术前神经功能JOA评分4-14分,平均9．6分。行颈前路常规手术入路,椎体开槽切骨达椎体后壁,范围超过后纵韧带骨化灶。利用后纵韧带钩插入后纵韧带下,钩起后纵韧带及骨化物,在后纵韧带与硬膜间形成一间隙,直视下用超薄型枪状咬骨钳切除后纵韧带及骨化物,而后植骨固定,恢复颈椎稳定性。结果随访6-36个月,平均16个月。术后JOA评分8～16分,平均12．8分,恢复率42％＇-92％,其中疗效优9例,良7例,可3例,优良率84．2％。4例患者术后并发脑脊液漏,保守治疗后均获得痊愈。术后CT和MR检查显示骨化后纵韧带切除完全,脊髓和硬膜囊形态恢复良好。结论后纵韧带钩可提高颈椎前路手术切除后纵韧带骨化物的安全性和有效性,适用于局限型和分节型、切除范围在两个椎节之间的颈椎后纵韧带骨化症患者。     

不离断后纵韧带的前路椎体-骨化物复合体可控前移融合术治疗颈椎多节段后纵韧带骨化症的疗效

目的 ：评估不离断后纵韧带颈椎前路椎体-骨化物复合体可控前移融合术(anterior controllable antedisplacement and fusion,ACAF)治疗颈椎多节段后纵韧带骨化症(ossification of the posterior longitudinal ligament,OPLL)的手术疗效。方法 ：回顾性分析2017年10月～2019年11月在我院行ACAF治疗的多节段颈椎OPLL患者73例,其中采用不离断后纵韧带的ACAF治疗的42例纳入非离断组(男32例,女10例,年龄55.8±9.7岁,随访时间2.4±0.4年),采用离断后纵韧带的ACAF治疗的31例纳入离断组(男25例,女6例,年龄56.7±11.4岁,随访时间2.3±0.3年)。记录两组患者的手术时间、出血量、住院时间和手术相关并发症。在术前和术后12个月的颈椎CT上测量椎管占位率、前移距离(术后椎管前后径-术前椎管前后径)、减压宽度、椎管前后径,评估手术减压情况;在术后7d和12个月的颈椎正侧位、动力位X线片和CT上观察棘突间隙活动变化、融合器内外骨桥形成以及椎体间总高度,评估术后...     

选择性颈后路单开门椎管扩大椎板成形术治疗孤立型颈椎后纵韧带骨化症的临床疗效

目的 :探讨选择性颈后路单开门椎管扩大椎板成形术治疗孤立型颈椎后纵韧带骨化症(ossification of the posterior longitudinal ligament,OPLL)的临床疗效,并与颈前路椎体次全切手术(anterior cervical corpectomy and fusion,ACCF)临床疗效进行比较。方法:回顾性分析2017年1月～2019年1月接受手术治疗且符合入组标准的40例孤立型颈椎OPLL患者的临床资料,其中行ACCF手术22例(ACCF组),行选择性颈后路单开门椎管扩大椎板成形术18例(LP组)。均获得12～24个月随访(ACCF组18.50±4.20个月,LP组18.60±4.50个月)。比较两组患者术前、术后3个月、末次随访时日本骨科协会(Japanese Orthopaedic Association,JOA)评分及颈痛视觉模拟评分(visual analogue score,VAS),比较两组患者末次随访时的神经功能改善率;比较两组患者术前、末次随访时颈椎曲度、颈椎活动度;比较两组患者手术出血量、手术时间、术后住院时间及术后并发症发...     

Association between serum leptin and bone metabolic markers, and the development of heterotopic ossification of the spinal ligament in female patients with ossification of the posterior longitudinal ligament

Obesity is a risk factor for ossification of the posterior longitudinal ligament (OPLL) of the spine, which is characterized by heterotopic bone formation in the posterior longitudinal spinal ligament. Hyperleptinemia is a common feature of obese people and leptin is believed to be an important factor in the pathogenesis of OPLL. However, the association between leptin and bone metabolism and the development of OPLL is not understood fully. The objective of the present study was to determine the association between serum leptin concentration and bone metabolic markers and the extent of heterotopic ossification of the spinal ligament in patients with OPLL. The serum concentrations of leptin, insulin, fructosamine, bone-specific alkaline phosphatase, and carboxyterminal propeptide of type I procollagen, urine deoxypyridinoline levels, and the number of vertebrae with OPLL involvement were measured in 125 (68 males and 57 females) patients with OPLL. The correlation between leptin and these other factors was then examined. Serum leptin and insulin concentrations were increased significantly in OPLL females compared to non-OPLL female controls. In the females with OPLL, serum leptin concentrations corrected for body mass index correlated positively with the number of vertebrae with OPLL involvement. In females, serum leptin levels were significantly higher in patients in whom OPLL extended to the thoracic and/or lumbar spine than in patients in whom OPLL was limited to the cervical spine. Our results suggest that hyperleptinemia, in combination with hyperinsulinemia, may contribute to the development of heterotopic ossification of the spinal ligament in female patients with OPLL.     

颈椎后纵韧带骨化成纤维细胞的培养及其生物学特性

目的探讨颈椎后纵韧带骨化(ossification of posterior longitudinal ligament,OPLL)成纤维细胞培养的方法及其生物学特性,为研究OPLL的病理、生理及发生机制等提供生物学基础。方法采集OPLL患者减压过程中未骨化的部分和颈椎外伤手术减压过程中正常后纵韧带,用原代培养的方法进行体外培养,倒置显微镜观察细胞形态和分泌形成钙结节的过程,并应用Von Kossa方法染色;MTT比色法分析细胞增殖特性;碱性磷酸酶(ALP)活性定量测定和骨钙素(OC)测定比较病变组和正常组差别。结果经Von Kossa染色后镜下显示黑色结节,证实为钙结节;细胞数量从第3 d开始明显增加,并快于正常组;病变组ALP分泌量为(28.56±0.65)U/gprot、OC分泌量为(1.04±0.14)ng/ml,明显高于正常组(P相似文献   

颈椎后纵韧带骨化症前路手术的多因素分析

[目的]探讨影响颈椎后纵韧带骨化症前路手术疗效的相关因素。[方法]48例颈椎后纵韧带骨化症患者，行前路手术治疗，随访1～4年，平均2．1年。根据术后神经功能JOA评分改善率，将患者分为预后良好、预后不佳2组。采用多元Logistic回归分析患者年龄、性别、神经功能、症状持续时间、合并糖尿病、Pavlov值、椎管狭窄率、骨化物分型、CT双影征、脊髓高信号、手术范围以及骨化物处理对患者手术疗效的影响。[结果]骨化物的处理方式是影响患者疗效的唯一因素（P=0．0067）。[结论]前路手术彻底切除骨化之后纵韧带，对脊髓充分减压是前路手术治疗颈椎后纵韧带骨化症的关键。     

Recent progress in the study of pathogenesis of ossification of the posterior longitudinal ligament

The pathogenesis of ossification of the posterior longitudinal ligament (OPLL) is still unknown. Gene analysis and molecular biology have been introduced in recent years, and etiologic and pathological clarifications are being achieved. An important role of the genetic background in the development of this disease was demonstrated by pedigree survey, twin survey, and HLA haplotype study. The results of gene linkage study showed that patients with OPLL have a significantly higher incidence of genetic abnormalities found in the XI collagen (α)² gene (COL11A2) region. From the gene mapping of this abnormality, the abnormal N-propeptide of the COL11A2 gene was found to be responsible. We are planning to undertake genetic analysis of the whole of chromosome VI to find the pathogenic genes responsible for OPLL in addition to COL11A2. A cell biological approach is also necessary to make clear the relationship between abnormalities of the COL11A2 gene and ossification of the ligament. In future, identification of the susceptible gene, elucidation of its function, and study toward the development of preventive and therapeutic drugs will advance. Received for publication on Aug. 20, 1999     

Surgical management of cervical cord injury with ossification of the cervical posterior longitudinal ligament

Objective: To identify an appropriate surgical approach for the management of cervical cord injury with ossification of the posterior longitudinal ligament. Methods: A retrospective study of 25 cases of cervical cord injury with ossification of the posterior longitudinal ligament was performed. Two cases were classified as Frankel grade A, three as grade B, fourteen as grade C, and six as grade D. Treatment procedures consisted of anterior decompression with instrumentation (twelve patients), posterior decompression (eight patients), and combined anterior and posterior decompression (five patients). Results: There were no iatrogenic injuries of great vessels, trachea, esophagus or spinal cord. All patients were followed up for 15–86 months (average, 38.3 months). All segment with anterior fixation attained solid fusion, without implants loosening or breakage. No reclosed open‐door was found after posterior laminoplasty. Twenty‐one patients improved by one to two Frankel grades. The patients with complete spinal cord injury achieved no neurologic recovery, but did experience relief of upper limb pain or numbness. Conclusion: The surgical outcomes of cervical cord injury with ossification of the posterior longitudinal ligament were satisfactory. It is important to select a suitable surgical approach according to the findings on radiological imaging and the clinical characteristics and general condition of the patients.     

两种前路术式治疗严重颈椎后纵韧带骨化症的疗效及神经功能恶化率对比

【摘要】 目的：比较颈椎椎体骨化物复合体可控性前移融合术（anterior controllable antedisplacement and fusion,ACAF）与颈前路椎体次全切除减压融合术（anterior cervical corpectomy and fusion,ACCF）治疗严重颈椎后纵韧带骨化症（ossification of the posterior longitudinal ligament,OPLL）的疗效及术后神经功能恶化率。方法：回顾性分析2018年3月～2019年3月在我院接受颈前路手术治疗的72例严重OPLL患者（椎管侵占率≥50%）的临床资料,其中35例采用ACAF治疗（ACAF组）,37例采用ACCF治疗（ACCF组）,术后随访6～12个月。收集两组患者手术时年龄、性别、随访时间,术后2周内神经功能恶化发生情况、原因及预后,术前、术后2周内及末次随访时采用JOA评分评估神经功能,同时在术前和末次访时的颈椎CT和MRI检查图片上观察骨化物类型,测量椎管侵占率、椎管最狭窄处的减压宽度、椎管面积及脊髓前后径。结果：两组患者手术时年龄、性别比、随访时间、骨化物类型、术前椎管侵占率、椎管面积、脊髓前后径、JOA评分等均无统计学差异（P>0.05）。术后2周内,ACCF组有10例出现神经功能恶化,发生率为27.0%,其中6例系术中损伤脊髓,2例为硬膜外血肿压迫脊髓,2例为骨化物残留;ACAF组2例出现神经功能恶化,发生率为5.7%,均因骨化物残留所致。两组术后神经功能恶化率有统计学差异（P<0.05）。末次随访时,ACAF组减压宽度大于ACCF组（18.5±2.5mm vs 16.9±1.9mm）,差异有统计学意义（P<0.05）;椎管面积及脊髓前后径两组间比较差异无统计学意义（144.9±31.2mm2 vs 142.1±22.3mm2,P>0.05;5.5±0.5mm vs 5.2±1.4mm,P>0.05）;两组患者JOA评分较术前均明显改善,ACAF组JOA评分改善率大于ACCF组[（79.5±8.7）% vs （68.9±20.3）%,P<0.05]。结论：相较于ACCF,ACAF治疗严重颈椎OPLL能够获得更加满意的临床疗效,且降低了术后神经功能恶化率;但在开展ACAF早期仍存在发生术后神经功能恶化的潜在风险。     

Initiation and progression of ossification of the posterior longitudinal ligament of the cervical spine in the hereditary spinal hyperostotic mouse (twy/twy)

Introduction  

Ossification of the posterior longitudinal ligament (OPLL) is a significantly critical pathology that can eventually cause serious myelopathy. Ossification commences in the vertebral posterior longitudinal ligaments, and intensifies and spreads with the progression of the disease, resulting in osseous projections and compression of the spinal cord. However, the paucity of histological studies the underlying mechanisms of calcification and ossification processes remain obscure. The pathological process could be simulated in the ossifying process of the ligament in mutant spinal hyperostotic mouse (twy/twy). The aim of this study is to observe that enlargement of the nucleus pulposus followed by herniation, disruption and regenerative proliferation of annulus fibrosus cartilaginous tissues participated in the initiation of ossification of the posterior longitudinal ligament of twy/twy mice.     

Spinal cord cross-sectional area during flexion and extension in the patients with cervical ossification of posterior longitudinal ligament

Purpose

The pathomechanism of cervical myelopathy due to cervical ossification of posterior longitudinal ligament (C-OPLL) remains unclear. No previous literature has quantified the influence of dynamic factors on cervical myelopathy due to C-OPLL. The purpose was to investigate the influence of dynamic factors on the spinal column in the patients with C-OPLL using CT scan after myelography (MCT).

Methods

The study included 41 patients with cervical myelopathy due to C-OPLL. An MCT was done during neck flexion and extension, and spinal cord cross-sectional areas (SCCSA) were measured at each disc level between C2/3 and C7/T1. Ossification morphology at each segment was divided into three groups, connection department, coating part, and non-connection department of OPLL group. Dynamic changes of SCCSA in each group of ossification morphology were calculated. The relationship between clinical results and SCCSA at the narrowest level was investigated.

Results

MCT showed SCCSA changes during neck extension; 7.4 ± 5.1 mm² in the connection department, 5.8 ± 6.0 mm² in the coating part, and 6.7 ± 6.4 mm² in the non-connection department of OPLL group. There difference was not statistically significant. There was a weak correlation between the JOA score and SCCSA at the narrowest level (R = 0.49). There was no significant correlation between the recovery rate of JOA score and SCCSA at the narrowest level (R = 0.37).

Conclusion

Dynamic factors are seen both in cervical myelopathy patients with the continuous type of OPLL and others. Deterioration of myelopathy could be induced by motion effects even in the connection department of OPLL.     

前路椎体骨化物复合体前移融合术治疗颈椎后纵韧带骨化症的研究进展

颈椎后纵韧带骨化症（OPLL）是颈椎后纵韧带发生异位骨化并不断增生压迫颈脊髓,引起肢体感觉和躯体运动不同程度障碍及脏器植物神经功能紊乱的一种疾病,在中国其发病率约为0.077‰^[1]。虽然颈椎OPLL的传统手术方式已得到了长足的发展和完善,但复杂的长节段颈椎OPLL的术式选择仍然没有明确的定论。近年来,随着对颈椎解剖学研究的深化及手术方法的改进,海军军医大学长征医院史建刚^[2]团队创造性地通过将椎体与骨化的后纵韧带整体向腹侧平移的方式实现对颈椎椎管的可控减压,即颈椎前路椎体骨化物复合体前移融合术（ACAF）。该术式通过磨除部分椎体前柱实现前路直接减压,既可以将椎管内减压转化为直观的椎体前移,又规避了如何处理骨化物粘连的难题,降低了术后并发症的发生率,为颈椎OPLL的治疗带来了新的选择;45例患者ACAF术后平均随访4个月,疗效满意^[3]。近5年的相关文献表明,ACAF在治疗长节段颈椎OPLL导致的颈椎椎管狭窄症方面具有明显的优势,但由于ACAF为新兴术式,在手术适应证、禁忌证方面仍未达成一定共识;在对于不同类型颈椎OPLL患者ACAF是否适用、手术相关并发症及其预防手段方面,仍有较大的讨论空间。