轴向载荷对双节段颈椎人工椎间盘置换邻下位关节突关节压力影响

【摘 要】 目的 探讨轴向载荷对双节段颈椎人工椎间盘置换和前路椎间融合内固定对邻下位节段关节突关节内压力的影响,为双节段人工颈椎间盘置换的临床运用提供生物力学依据。 方法 取11具新鲜完整的成人下颈段标本,按实验先后分别制成C4/5、C5/6椎间盘完整、椎间盘置换、椎间融合三个模型组,在标本上施加轴向分级载荷,将微型阻电式压力传感器置入C5/6、C6/7关节突关节内,测量合组各分级载荷下C5/6、C6/7关节突关节内的压力。 结果 1.在轴向加载下,下位节段关节突关节内的压力随着施加载荷的增大而增大。 2. C4/5、C5/6双节段人工椎间盘置换组与椎间盘完整组相比下位置换节段和邻近下位节段关节突关节内的压力变化相近,无显著性差异 (P>0.05)。3. C4/5、C5/6椎间融合组与人工椎间盘置换组、椎间盘完整组相比邻近下位节段关节突关节内的压力高,有显著性差异(P<0.05)。 结论 1. 颈椎双节段人工椎间盘置换后置换下位节段和邻近下位节段关节突关节内压力与完整标本相近,提示颈椎双节段人工椎间盘置换能够重建颈椎生物力学性能。2. 颈椎双节段椎间盘摘除融合内固定后邻近下位关节突关节压力增加,可能是多节段颈椎融合术后邻近节段发生退变或退变加速的原因之一     

成人下颈椎椎体与关节突关节倾角的X射线测量数据

背景：颈椎关节突关节倾角的文献多采用X射线侧位片椎体下缘线测量法,结果有较明显差异。对不同节段关节突关节倾角差异及因年龄的结构退行性变对其影响的研究较少。 目的：测量成人下颈椎(C3~7)关节突关节的倾角,并探讨年龄因素对倾角的影响。 设计、时间及地点：随机分组,测量实验,于2007-03/06在汕头大学医学院附属粤北人民医院完成。 对象：选取2000-01/2006-12汕头大学医学院附属粤北人民医院骨科120例成年人颈椎侧位X射线平片,男58例,女62例;年龄16~75岁。 方法：120例成人颈椎侧位X射线平片按年龄分为3组：16~30岁组(n=38),31~50岁组(n=43),51~75岁组(n=39)。以传统的椎体下缘线和自行设计的椎体中线方法测量C3~7关节突关节倾角,比较2种方法不同年龄段的测量数据。 主要观察指标：椎体下缘线法和椎体中线法测量颈椎C3~7关节突关节倾角数值。 结果：①两种方法测量的下颈椎关节突关节倾角在30°~72°,各节段均值均大于50°,以C5为中心分布,C7>C3>C4>C6>C5。②两种方法测量的倾角均随年龄增大而减小,C5变化最明显。16~30岁组各节段关节突关节倾角差异均无显著性意义(P > 0.05);椎体下缘线法测量31~50岁组C4~C6节段关节突关节倾角小于椎体中线法(P < 0.01);在51~75岁组,椎体下缘线法测量C3~C6节段关节突关节倾角小于椎体中线法(P < 0.05~0.01)。 结论：两种方法测量的倾角均随年龄增大而减小,椎体中线法受颈椎年龄因素退变的影响较小,是相对客观的一种测量方法。     

人工腰椎间盘置换后下位关节突关节内压力的变化*★

目的：腰椎间盘和关节突关节共同维持腰椎的稳定，任何一个部分的退行性变都将引起另两部分的退变。观察SB Charite人工腰椎间盘假体置换对相邻下位关节突关节内压力的影响，以提供人工椎间盘临床应用的生物力学参数。 方法：实验于2003-03在国防科技大学航天与材料工程学院力学实验室完成。①实验材料：10具新鲜成人尸体腰椎标本，包括L2~5椎体及其椎间盘，死者均为急性脑死亡的健康青壮年。肉眼及X射线观察以排除标本无畸形、退行性变及结构性破坏。剔除椎旁肌肉及其筋膜组织，保留所有的韧带、椎间盘及关节囊并维持其完整性。②实验方法及评估：将Ω状微型电阻式压力传感器置入L4/5关节突关节，分别测量L3/4椎间盘完整和人工椎间盘置换两种状态下轴向（400～2 000 N）、后伸、对侧弯和同侧弯(2~10 N·m)载荷4种工况时L4/5关节突关节内的压力。 结果：纳入成人尸体腰椎标本共10具，均进入结果分析，实验过程中标本无破坏和脱落。轴向、后伸、同侧弯及对侧弯加载条件下，人工椎间盘置换组与椎间盘完整组比较，下位关节突关节内压力差异均无显著性（P > 0.05）。 结论：①人工腰椎间盘置换后相邻下位关节突关节内压力与正常时无明显改变。②人工椎间盘置换在重建腰椎生物力学性能的同时不会引起相邻下位关节突关节内压力的改变。     

腰椎关节突关节融合：从植骨融合到螺钉和融合器的应用

背景：腰椎关节突关节是脊柱后柱的重要结构,其固定与融合在腰椎后路手术被广泛应用。目的：阐述了各种腰椎关节突关节融合技术的优缺点和疗效。方法：应用计算机检索PubMed数据库、CNKI数据库中有关腰椎关节突关节融合方法的文献。结果与结论：传统的关节突关节融合方法为关节突关节V形开槽,然后植入松质骨,不需要作大范围的剥离,创伤小,所需植骨量较少,融合率高,缺点是即刻的稳定性较差。经关节突关节螺钉固定联合横突间融合可以提高植骨融合率,但存在融合失败、术后症状缓解不明显、螺钉松动和断裂、硬膜撕裂、螺钉穿刺到椎管引起神经损伤等并发症。圆柱体嵌入椭圆体的融合器有利于融合器与关节面充分的接触,同时提高了融合器的稳定性和抗移位能力。目前对腰椎关节突关节融合的研究远没有对后外侧融合的研究那么充分,系统的生物力学研究和中远期临床疗效及并发症的研究有待深入研究。     

人工椎间盘置换对腰椎小关节应力影响的三维有限元分析

背景：近年来随着对脊柱生物力学研究的深入,人工椎间盘被认为是治疗腰椎退行性变较理想的方法,但目前对人工腰椎间盘的生物力学研究还非常有限。 目的：建立腰椎运动节段人工椎间盘置换的三维有限元模型并进行生物力学分析,观察人工椎间盘置换对腰椎小关节应力的影响。 方法：在已建立的正常腰椎运动节段三维有限元模型的基础上去除L4~5椎间盘、上下终板的有限元单元,加入SB-Chaite Ⅲ型人工椎间盘的有限元模型,保留L4~5椎间隙的纤维环及相关韧带,形成L4~5运动节段人工椎间盘置换的三维有限元模型。对三维有限元模型在垂直压缩、前屈、后伸、侧弯等不同载荷下进行生物力学分析,记录小关节的应力,并与正常运动节段三维有限元模型相应部位的应力进行对比。 结果与结论：生物力学分析结果显示,人工椎间盘置换后：①垂直压缩时上下椎体、双侧小关节内应力与正常节段相比差异无显著性意义(P > 0.01)。②前屈、后伸时上下椎体前、后方及双侧小关节内应力与正常节段相比差异无显著性意义(P > 0.01)。③侧弯时上下椎体左右两侧及双侧小关节内应力与正常节段相比差异无显著性意义(P > 0.01)。提示人工腰椎间盘置换后小关节应力可保持在正常运动节段的水平,人工腰椎间盘置换可以达到腰椎生物力学性能重建的目的。     

三维图像测量青少年颈椎钩突的形态特征

背景：钩突作为钩椎关节重要组成部分之一,其形态直接影响着颈椎的稳定性和发病率。 目的：通过影像学扫描和三维重建分析青少年颈椎钩突的形态特征及发育规律。 方法：选择无外伤、无神经症状和体征的6~20岁青少年66名,行多排螺旋CT薄层扫描(0.625~1.25 mm),范围C1~T1,将原始数据以DICOM格式导入三维重建软件进行相关指标测量,并按性别、年龄分组进行统计分析。 结果与结论：青少年钩突基底长、宽和钩突高、间距从C1~C7均呈递增趋势,且随年龄增长也逐渐递增,但上述所有指标在左右侧别和性别方面差异无显著性意义。钩突倾角在各年龄段中均无明显规律,但变异度较大。表明利用影像资料的三维重建可反映出青少年颈椎钩突随年龄变化的规律及发育特征,为颈椎病的诊断与临床应用提供详实理论依据。     

下颈椎前路内固定联合后路经关节金属螺钉置入固定的生物力学稳定性

背景：对退变性颈椎管狭窄单纯采用前路椎体次全切除或椎间盘切除或单纯后路单开门椎管扩大成行均不能彻底完成脊髓减压和脊柱三柱稳定。 目的：探讨下颈椎前路固定联合后路经关节螺钉固定的生物力学稳定性。 方法：正常成人尸体颈椎标本,每具分别制作以下两种模型：①经后路C3~C7单开门和下颈椎前路C5椎体次全切除钛网支撑植骨、ORION内固定模型(对照组)。②经后路C3~C7单开门和经关节螺钉内固定及下颈椎前路C5椎体次全切除钛网内植骨、ORION内固定模型(实验组)。 结果与结论：实验组在前屈、后伸、左、右侧屈及左、右旋转移位角度均小于对照组(P < 0.001)。提示：①在生物力学实验中,下颈椎前路固定联合后路经关突节螺钉固定的生物力学性能优良,对抗前屈、后伸、左、右旋转的作用力更强,颈椎可获得更可靠的稳定性。②下颈椎前路固定联合后路经关节螺钉固定在对抗颈椎前屈运动时力学稳定性更为强大。     

阿特拉斯与第一颈椎

寰椎是第一颈椎,呈环状,无椎体、棘突和关节突,由前弓、后弓和两个侧块组成。寰椎的上方为颅骨,通过寰椎的连接,整个脊椎像一根擎天柱撑起人体的“苍穹”——头颅。     

颅内少突胶质瘤转移至颈椎管内1例

正1病例资料患者,男,53岁,因头痛1个月,加重伴头晕1周入院。神经系统查体无阳性体征。头部MRI示:右侧额叶、岛叶、基底节区见不规则团块状等T_1、等T_2为主混杂信号影,境界不清,其内可见斑片状长T_2信号,病灶周围及右侧颞极见片状长T_1、长T_2水肿信号影环绕,周围组织受压改变,中线结构左偏;增强扫描示右侧额叶、岛叶、基底节区病变呈不均匀片状、环状强化(图1A、1B)。在全麻下行右侧额叶、岛叶病变切除     

颈椎动态稳定器置入非融合颈椎的生物力学分析

背景：颈椎动态稳定器的解剖型设计与正常椎间盘应具有相似的生物力学特点,其动态性设计具有轴向顺应性以及震荡吸收功能,而前缘倒齿嵌入上下椎体可获得足够的轴向稳定性。 目的：比较颈椎前路融合内固定和颈椎动态稳定器置入非融合后颈椎相关生物力学指标变化。 方法：将6具新鲜人C2~C7颈段脊柱标本随机分为3组,在完整颈椎测试后分别行C5、6前路减压颈椎动态稳定器DCI置入,C5、6前路减压单纯Cage融合内固定,C5、6前路减压颈椎前路一体化钢板椎间融合器融合内固定。检测各组标本前屈、后伸、左右侧屈不同生理运动工况并施加2.0 N•m纯力偶矩,颈椎标本C5~6上下邻近节段手术前后活动度大小。 结果与结论：3种内固定后C5~6上下邻近节段较正常颈椎标本前屈、后伸和左右侧屈关节活动度值均有所增加,且表现出良好的即时稳定性,但颈椎动态稳定器置入组最接近正常值;3组间C5~6上下邻近节段关节活动度差异无显著性意义。表明颈椎动态稳定器置入后对邻近节段椎体活动度无明显影响或影响甚小,在一定程度上减小假体与其邻近椎体轴向应力,有效地维持颈椎活动。     

A rare case of cervical facet joint and synovial cyst at C5/C6

Lumbar synovial cysts are uncommon, and particularly rare at cervical levels. We report a 40-year-old woman who presented with pain distribution in the typical C6 dermatome. MRI revealed a right-sided large extradural cystic lesion adjacent to the C5/C6 facet joint that was hyperintense on T2-weighted MRI and hypointense on T1-weighted MRI. The patient underwent posterior cervical surgery at the C5/C6 level which involved posterior decompressive unilateral laminotomy and excision of the C5/C6 facet joint cyst. Following complete facetectomy of the right C5/C6 facet joint and exposure of the C6 nerve throughout its foraminal course, instrumented fusion was performed. Following the procedure, the patient had an uneventful recovery with relief of her radicular symptoms at follow-up clinical review.     

Single-level bilateral facet joint hypertrophy causing thoracic spinal canal stenosis

Thoracic canal stenosis caused by hypertrophy of the posterior spinal elements is rare. We report an unusual case of bilateral zygapophyseal joint hypertrophy occurring solely at thoracic levels T10–11, producing bilateral leg weakness and numbness. The diagnosis was established using CT scans and MRI. A wide decompressive laminectomy and posterolateral bone fusion was performed. Postoperatively there was a marked improvement in symptoms and signs. We present a literature review on bilateral single-level facet joint hypertrophy producing canal stenosis and report our experience.     

Transient tetraplegia after cervical facet joint injection for chronic neck pain administered without imaging guidance

We report about a patient in whom transient tetraplegia with intact proprioception occurred immediately after infiltration of a facet joint at the C6 level guided by anatomical landmarks. After positioning the patient supine and applying atropine and oxygen, respiration and circulation were stable and all symptoms resolved within the next 30 min. The type of neurological pattern and the course of disease suggest an inadvertent injection into a cervical radicular artery that reinforces the anterior spinal artery. This complication is potentially serious and may be permanently disabling or life threatening. It should be considered by any clinician performing "blind" zygapophysial joint injections in the cervical spine. Using imaging guidance should help prevent this type of complication.     

Changes in the axial orientation of the zygapophyseal joint in the subaxial cervical spine from childhood to middle-age,and the biomechanical implications of these changes

The objective of this study was to investigate the effect of age on facet orientation (FO) of the cervical spine during development, maturation, and degeneration. Computed tomography (CT) data of the cervical spine of 131 subjects without pathology of the cervical spine were analyzed. Subjects were categorized as: pediatric (n = 36, 8–16 years old), young adult (n = 33, 18–24 years old), and middle-age (n = 62, 40–59 years old). Serial CT scans were reconstructed by image processing. The FO in the axial plane was measured bilaterally at each vertebral level from C3/4 to C6/7. Differences in FO were analyzed between the 3 groups. The degree of external rotation of FO significantly decreased at C3/4 and C4/5 with increasing in age, and maximum external rotation was observed at C5/6. The external rotation at C6/7 increased from pediatric to young adulthood, but decreased from young adults to middle-aged adults. The dominant external rotation was seen in C4/5 and C5/6 in the pediatric age group, C5/6 and C6/7 in young adults, and C4/5 and C5/6 in middle-aged adults. These results lead us to conclude that FO in the axial plane exhibits significant differences with age. The degree of external rotation with respect to FO at each vertebral level is comparable to changes in cervical spinal dynamics with age. Hence, FO in the axial plane is a biomechanical parameter that can be used to assess changes in the cervical spinal during maturation and degeneration.     

Septic arthritis of the lumbar facet joint. Case and literature review

Septic Arthritis of the facet joint (SAFJ) is an uncommon but severe condition of the spine with only 61 cases published to date. Diagnosis is notoriously difficult and can take several months which can lead to significant delays in treatment. We report a case of a 52-year-old female with 2-month history of back pain diagnosed with septic arthritis of the left lumbar L4/5 facet joint and associated epidural abscess. She presented with no fevers, normal neurological examination and normal blood parameters posing a diagnostic challenge. In this report we conclude normal inflammatory markers cannot be used as exclusion criteria for the disease. We also review the body of literature to summarise the key features of the condition to assist clinicians in its diagnosis.     

前路手术治疗多节段颈椎退变的临床及生物力学研究

目的探讨多节段颈椎病前路手术的治疗结果,并采用力学方法评价内固定对颈椎稳定性的影响.方法 38例多节段颈椎病患者分为二组,A组:颈椎前路减压加椎体间植骨;B组:颈椎前路减压、植骨,加内固定.生物力学实验:6具成年颈椎标本分别进行三个椎间盘切除;椎间隙植骨;植骨加内固定等处理,并进行轴向压缩(300 N)、侧弯(2 Nm),及轴向扭转(2 Nm)加载.结果 A组中植骨块脱出发生率为45%,平均移位22%;骨不连发生率10%;术后神经功能优良率75%.B组无植骨块脱出,颈椎融合率100%;术后神经功能优良率83%.生物力学实验结果:3个节段的椎间盘切除后,颈椎在多个方向上的严重失稳,植骨可部分改善稳定性,内固定后明显改善颈椎稳定.结论应用颈椎前路内固定能预防植骨块的移位,增加颈椎融合率,提高临床疗效.     

Comparison between Anterior Cervical Decompression with Fusion and Posterior Cervical Fusion with Wide Facetectomy for Treatment of Severe Bony Foraminal Stenosis

ObjectiveTo compare the anterior cervical discectomy and fusion (ACDF) and posterior cervical fusion (PCF) with wide facetectomy in the treatment of parallel-shaped bony foraminal stenosis (FS). MethodsThirty-six patients underwent surgery due to one-or-two levels of parallel-shaped cervical FS. ACDF was performed in 16 patients, and PCF using CPS was performed in 20 patients. All patients were followed up at 1, 3, 6, and 12 months postoperatively. Standardized outcome measures such as Numeric rating scale (NRS) score for arm/neck pain and Neck disability index (NDI) were evaluated. Cervical radiographs were used to compare the C2–7 Cobb’s angle, segmental angle, and fusion rates. ResultsThere was an improvement in NRS scores after both approaches for radicular arm pain (mean change -6.78 vs. -8.14, p=0.012), neck pain (mean change -1.67 vs. -4.36, p=0.038), and NDI score (-19.69 vs. -18.15, p=0.794). The segmental angle improvement was greater in the ACDF group than in the posterior group (9.4°±2.7° vs. 3.3°±5.1°, p=0.004). However, there was no significant difference in C2–7 Cobb angle between groups (16.2°±7.9° vs. 14.8°±8.5°, p=0.142). As a complication, dysphagia was observed in one case of the ACDF group. ConclusionIn the treatment of parallel-shaped bony FS up to two surgical levels, segmental angle improvement was more favorable in patients who underwent ACDF. However, PCF with wide facetectomy using CPS should be considered as an alternative treatment option in cases where the anterior approach is burdensome.     

Protecting facet joints post-lumbar discectomy: Barricaid annular closure device reduces risk of facet degeneration

Lumbar discectomy is an effective treatment for lumbar disc herniation (LDH). Although the majority of patients experience successful outcomes, a significant fraction will experience a recurrence of their back pain due to facet joint degeneration. Facet joint degeneration after discectomy may be the result of excessive nuclear removal, disc space narrowing, and annular injury. This study investigated whether implantation with the Barricaid annular closure device (ACD) during discectomy reduced the rate of facet degeneration. Inclusion criteria were primary lumbar disc herniation failing conservative treatment, Visual Analog Scale (VAS) Leg ≥ 40/100, Oswestry Disability Index (ODI) ≥ 40/100 and defects that were ≤60 mm² (Barricaid arm only), and patient age 18–75. CT interpretations were collected preoperatively and 12 months post-discectomy. Patients implanted with Barricaid had significantly reduced rates and grades of facet degeneration than patients without Barricaid. Reinforcing the annulus fibrosus with Barricaid during lumbar discectomy may slow the progression of facet joint degeneration.     

Treatment of old cervical bilateral facet dislocation: Case report and literature review

Late diagnosis of cervical bilateral facet dislocation is rare and contributes to concerns in the management of these patients.We present a case of a 44-year-old woman presented 8 months after a trauma with persistent neck pain, without neurological deficits. A bilateral C5-C6 facet dislocation was identified. The patient was treated with a combined C5-C6 approach: posterior facet joints release, anterior discectomy and fusion, bilateral posterior fixation. Surgery was performed under intraoperative neurophysiological monitoring. The postoperative period was uneventful, and the patient presented functional improvement.Late surgical treatment of bilateral cervical facet dislocation is safe and feasible. Combined procedures are needed for proper reduction and stabilization of the spine. Intraoperative neurophysiological monitoring adds value to this technique contributing to good outcomes.     

Localization of substance P and neurofilament immunoreactive fibers in the lumbar facet joint capsule and supraspinous ligament of the rabbit

An indirect immunofluorescence method was utilized to identify substance P-like immunoreactive (SPLI) and neurofilament protein immunoreactive (NFIR) fibers in the lumbar facet joint capsule and supraspinous ligament of the rabbit. The results demonstrated a large population of NFIR fibers, indicating that these tissues are richly innervated, and a smaller population of SPLI fibers. In some fibers, neurofilament protein and substance P were colocalized. The data suggest that the facet joint capsule and the supraspinous ligament contain SPLI nociceptive fibers that could be a source of low back pain.