Application of magnetic resonance imaging in cervical spondylotic myelopathy

Cervical spondylotic myelopathy(CSM) is the most common cause of spinal cord dysfunction and is caused by static or dynamic repeated compression of the spinal cord resulting from degenerative arthritis of the cervical spine and some biological injuries to the cervical spine. The T2 signal change on conventional magnetic resonance imaging(MRI) is most commonly associated with neurological deficits. Diffusion tensor imaging and MR spectroscopy show altered microstructure and biochemistry that reflect patient-specific pathogenesis and can be used to predict neurological outcome and response to intervention. Functional MRI can help to assess the neurological functional recovery after decompression surgery for CSM.

Multilevel cervical spondylotic myelopathy treated by anterior cervical decompression in subsection and autograft fusion

Objective：To investigate a novel surgical method for multilevel cervical spondylotic myelopathy （CSM）. Methods： Totally 21 patients with multilevel CSM undergoing a novel surgical procedure from April 2001 to January 2004 were analyzed retrospectively. All patients experienced anterior cervical decompression surgery in subsection, autograft fusion and internal fixation. Preoperative, immediate postoperative and follow-up image data, X-rays and semi-quantitative Japanese orthopaedics association （JOA） scores were used to evaluate the restoration of lordosis （Cobb＇s angle）, intervertebral heights, the stability of the cervical spine and the improvement of neurological impairment. Results： Preoperative symptoms were markedly alleviated or disappeared in most of the patients. According to the JOA scores, the ratio of improvement in neurological function was 72. 2%, including excellent in 9 cases （42.9%）, good in 7 cases （33.3%）, fair in 3 cases （14.3%） and poor in 2 cases （9.5%）. Immediate postoperative X-rays showed obvious improvements in lordosis and in the intervertebral height of the cervical spine （P〈0. 01）. There is no evidence of instrument failure during the mean follow-up period of 14. 2 months （9-24 months, P〉0. 01）. Conclusion：Anterior cervical decompression in subsection, autograft fusion and internal fixation is a rational effective method for the surgical treatment of multilevel CSM.

Cervical spondylotic myelopathy with syringomyelia presenting as hip Charcot neuroarthropathy:A case report and review of literature

BACKGROUND Charcot neuroarthropathy(CN)is a systemic disease characterized by progressive bone loss and destruction,which is usually closely related to diabetes,HIV,etc.However,CN caused by syringomyelia accounts for only 5%of CN cases;the shoulder and elbow are most often involved,and the hip joint is rarely affected.As a rare factor,cervical spondylotic myelopathy(CSM)can be associated with syringomyelia,which is scarcely reported in the literature.Here,we present the first case report to date of CN of the hip caused by syringomyelia secondary to CSM.CASE SUMMARY We describe a 76-year-old male patient who was diagnosed with CSM due to neck pain and weakness of limbs 16 years ago.Four years ago,he noticed recurrent swelling of the right hip with pain and was diagnosed with degenerative arthritis.Recently,however,his symptoms gradually worsened,and because of progressive pain,destabilization and weakness of the right hip,he was admitted to our hospital.Through systematic physical,radiographic and laboratory examinations,we finally reached a diagnosis:CN of the right hip associated with syringomyelia secondary to CSM.After comprehensive evaluation of the patient's condition,we performed right total hip arthroplasty.During the follow-up,the patient felt well clinically and could walk independently with a knee brace.CONCLUSION We suggest a possible etiological association between CSM and syringomyelia,which may reflect a potential pathogenesis of CN.We encourage clinicians to actively carry out a detailed medical history and comprehensive physical and imaging examinations in patients with joint lesions,especially chronic shoulder neck pain,to rule out the possibility of this association,which plays a crucial role in the early diagnosis of CN.Arthroplasty may no longer be an absolute contraindication to surgical treatment of CN.Reasonable selection of the surgical strategy can markedly improve the clinical symptoms and quality of life of patients.

Application of anterior decompression and reconstruction using titanium mesh with locking plates in the management of cervical spondylotic myelopathy

Objective：To observe the clinical effect of anterior decompression and reconstruction using titanium mesh with locking plates in the treatment of cervical spondylotic myelopathy. Methods：One hundred and twenty patients with cervical spondylotic myelopathy were treated by anterior decompression and reconstruction using titanium mesh with locking plates. There were 66 men and 54 women ranges in age from 37 to 72 Years（mean age, 58.3 years）. The mean Japanese orthopedic surgery association（JOA） scale was 9.6 points before operation. Patients were followed up clinically and radiographically. Results：Having stood surgery well, the operation time ranged between 60-100 min and bleeding during operation ranged between 20-200 ml. There were no case of postoperative infection, recurrent laryngeal nerve palsy, or esophageal or tracheal laceration or rupture. The average follow-up period was 14.3 months（range, 12 to 24 months） in 96 who were followed up. At the last follow-up visit the mean JOA scale had improved to 14.4 points, reflecting an improvement of 4.8 points. The results were considered to be excellent in 87 patients, good in 25, fair in 6, and poor in 2. No hardware-related complications or adjacent segment degenerative changes were encountered during the follow-up periods. Stable bone union was observed in all cases and the average time required for fusion was 5.7 months. Conclusion：Titanium mesh filled with autologous bone graft can avoid the complications associated with harvesting bone from the iliac crest donor site. When combined with cervical anterior locking plate, it can obtain satisfatory clinical results for the treatment of cervical spondylotic myelopathy.

Effect of Exercise Program on the Rehabilitation of Patients with Cervical Spondylotic Myelopathy

Study Design: A clinical trial of 30 consecutive patients with cervical spondylotic myelopathy (CSM). Objectives: To evaluate the effect of directed physical exercise in patients with CSM and to measure severity of myelopathy before and after an exercise program. Setting: Christian Medical College and Hospital, India. Participants: Thirty patients with CSM (mean age-54.1 years) with Nuricks Grade 2 and 3. Background: Myelopathy of the spinal cord can be caused by degenerative process of the cervical vertebrae and it is the most common type of dysfunction of the spinal cord in adult population. CSM usually develops insidiously and the natural history is not well understood, there is debate over the indication for operative Vs non operative management. Method: Patients participated in a 6-week exercise program, consisting of active exercises to upper and lower extremities, scapulothoracic muscles, and gentle stretches, sub maximal isometric exercises of the deep neck flexors, relaxation and immobilization with a cervical collar. Main Outcome Measures: The mJOA (modified Japanese orthopaedic association score) and ASIA motor and sensory scoring. The results were processed by using Wilcoxon sign rank test. Results: After comparing the values at the beginning and end of the program a satisfactory neurological result (sensorimotor/motor and sensory) was obtained in all thirty patients. Conclusion: The exercise program had a positive impact for most of the variables of the study. Exercise intervention with neck immobilization may be a treatment of choice in early stages of CSM. Future randomized controlled studies would provide insight into the effectiveness and clinical relevance of this intervention.

A wake up call for cervical spondylotic myelopathy in young age : a case report

A 30 yrs male,was admitted with complains ofneck pain,weakness in both upper and lower limbs forfour months and mild intermittent paresthesia along hisupper limbs.Physical examination showed mild senso-ry deficit

Functional evaluation using several evoked spinal cord potentials in elderly patients with cervical spondylotic myelopathy

BACKGROUND ： The recordings of evoked spinal cord potentials following epidural spinal cord stimulation are thought to be generated by volleys traversing the dorsal column pathway, and it may not directly reflect conduction defects in corticospinat tracts of cervical spinal cord. To our knowledge there has been few report using several evoked spinal cord potentials in function evaluation of the cervical spinal cord in eldedy patients with cervical spondylotic myelopathy （CSM）. OBJECTIVE： To investigate the function states of the cervical spinal cord in elderly patients with CSM and explore its pathophysictogic mechanism. DESIGN： Case observation SETTING ： Department of Orthopedics for the aged, Shenzhen Pingle Hospital of Orthopedics. Department of Orthopedic Surgery, Yamaguchi University School of Medicine. PARTICIPANTS ： A total of 23 eldedy patients with CSM who received treatment in the Department of Orthopedic Surgery, Yamaguchi University School of Medicine of Japan from January 2003 to February 2004 were enrolled in this study. Inclusive criteria： ① Multiple intervertebral levels of cervical spinal cord compression confirmed by MRI, e.g. 3 or more than 3 levels of compressin. ② Age ≥ 70 years old. ③ Numbness and sensory disturbance in the upper limbs and showed hyperreflexia in the lower limbs. Exclusive criteria： Patients with abnormal motor and sensory nerve conduction velocities in both upper and lower limbs were excluded. METHODS： Evoked spinal cord potentials （ESCPs） following transcranial electric stimulation （TCE-ESCPs）, epidural spinal cord stimulation （SpinaI-ESCPs） and median nerve stimulation （MN-ESCPs） were recorded in 23 patients from posterior epidural space intreoperatively. The abnormalities of TCE-ESCPs were defined as attenuation of amplitude of the D wave. The most cranial intervertebral level showing abnormal TCE-ESCPs with a marked reduction in size of the negative peak （reduction of over 50%） was considered as the upper level of the spinal cord lesion with respect to the corticospinal tract in white matter. The abnormalities of SpinaI-ESCPs were defined as marked reduction in the size of negative peak （reduction of over 50%）. The most caudal intervertebral level showing abnormal SpinaI-ESCPs was considered as the lower level of the spinal cord lesion with respect to the dorsal column pathway in white matter. The abnormalities of MN-ESCPs were defined as attenuation of the N13 amplitude,which was considered as the lesion level of the spinal cord with respect to the dorsal horn in gray matter. Radiological investigation： Lateral view of plain X-ray films was obtained in flexion and extension of the cervical spine. Instability of the cervical intervertebral level was determined as horizontal displacement of the vertebral body of over 3 mm. MAIN OUTCOME MEASURES ： The results of examination of TCE-ESCPs, SpinaI-ESCPs and MN-ESCPs in el- dedy patients with CSM. RESULTS： The 23 eldedy patients with CSM were participated in the result analysis. ①TCE-ESCPs： The impairment of the corticospinal tract in white matter at single intervertebral level was revealed in 18 of 23 patients by recordings of TCE-ESCPs （sensitivity 78%）. In the 18 patients, the lesion level was shown at the up- per cervical segment in 14 patients （C3-4n=10 and C4-5n=4）, and at the lower cervical segment in 4 patients （C5-6n=4）. ②Spinal-ESCPs： The impairment of the dorsal column pathway of white matter at single intervertebral level was revealed in 17 of 23 patients, by recordings of Spinal-ESCPs （sensitivity 74%）. In the 17 patients, the lesion level was presented at the upper cervical segment in 14 patients （C3-4n=10 and C4-5n=4）, and at the lower cervical segment in 3 patients （C5-6 n=3）. ③MN-ESCPs： All patients revealed abnormal MN-ESCPs at one or more intervertebral levels （sensitivity 100%）. The impairment at single intervertebral level was demonstrated in 17 patients, and the impairment at multiple intervertebral levels was shown in 4 patients （3 patients at the C3-4, C4-4, and C5-4~6, and one patient at the C4-5, C5-6, and C6-7）. ④Radiological findings： The Instability of the intervertebral level at the C3-4 or C4-5 motion segment was seen in 15 patients, with a total of 20 levels, and where 10 were at the C3-4 intervertebral level and 5 were at the C3-4, C4-5 intervertebral level. CONCLUSION ： The results suggest that in most elderly patients with CSM who have multiple intervertebral level compressions of the cervical spinal cord on MRI, white matter is impaired at the single cervical intervertebral level, and not only the dorsal column pathway, but also the corticospinal tract can be affected. Combined the findings of radiography, the excessive motion and instability of the C3-4 or C4-5 intervertebral level plays an important role in inducing the long tract lesion in elderly patients with CSM.

Spontaneous Cervical Epidural Hematomas in Mild Cervical Spondylotic Myelopathy Patients：An Analysis of 8 Cases

Spontaneous cervical epidural hematoms（SCEH） complicated with mild cervical spondylotic myelopathy（CSM） is a rare but emerging condition.Early diagnosis and treatment are important for good outcomes.This study aimed to investigate the clinical characteristics of this condition and to discuss the optimal treatment.The clinical data from 8 patients with SCEH plus CSM who were divided into two groups by treatment methods were retrospectively analyzed.The neurological function of the patients was assessed by Japanese Orthopedic Association（JOA） score before and after the surgical operations.Other factors were reviewed with medical records.Among them,4 out of the 8 patients underwent emergency surgery,and the rest 3 patients experienced an initial conservative treatment and ultimately received a laminectomy.We found that the Frankel Scale scores in most of the surgical patients were increased after surgery（6/7,85.7%）.However,the JOA scores at the 6th month after onset were even lower than those before onset in 3 of the operative cases,and those in the patients who were given conservative treatment showed no significant change.It was concluded that some patients with SCEH and CSM treated with a timely operation may obtain relief from their previous CSM symptoms.However,the final neurological deficits of these patients were closely related to the progressive interval which refers to the hours between the initial onset and the occurrence of new neurological deficits or mild CSM deterioration,no matter whether they accept the operation.We found the crucial progressive interval may be in 9 h.Early MRI and prompt neurosurgical intervention are also important to improve the neurological deficits.

Clinical Study of Acupotomy Trinity Lysis on Cervical Spondylotic Myelopathy with Liver and Kidney Deficiency Syndrome

Objective:To compare the therapeutic effects of acupotomy trinity lysis and traditional acupotomy on cervical spondylotic myelopathy.Methods:A total of 205 patients with cervical spondylotic myelopathy of liver and kidney deficiency syndrome were randomly divided into the experimental group(105 cases)and the control group(100 cases).The experimental group was relaxed with acupotomy in three positions:Heaven(tian),Human(ren)and Earth(di).Traditional acupotomy was used to relax Ashi acupoints of the affected vertebra in the control group.One treatment was conducted in one week,and the duration of one course of treatment was three weeks.The VAS,JOA score and NDI index were observed after treatment.Results:Before and after treatment,the total treatment efficiency of the treatment group was 95.23%,and that of the control group was 80.00%,there was significant difference between the two groups,P<0.05;Before operation,there was no significant difference in JOA score,NDI index score,and VAS score between the treatment group and the control group(P>0.05);there was no significant difference after 1 week(P>0.05),but there were significant differences between the two groups 2 weeks and 3 weeks after operation(P<0.05).Conclusion:Acupotomy trinity lysis is a safe,effective and economical treatment for cervical spondylotic myelopathy.

Selection of surgical methods for thoracic ossification of ligamentum flavum combined with cervical spondylotic myelopathy

Objective To investigate the difference between different surgical methods for thoracic ossification of ligamentum flavum(OLF) combined with cervical spondylotic myelopathy(CSM) . Methods From January 1991 to January 2003,56 cases

CLINICAL STUDY OF MOTOR EVOKED POTENTIALS BY MAGNETIC STIMULATION IN CERVICAL SPONDYLOTIC MYELOPATHY

The combined use of motor .yoked pot'ntlais (MEPs) with F way, recording was cornpared with somatesemory evoked potentials (SEPs) in order to evaluate the clinical value or MEPs incervical spondylotic myelopathy. Magnetic stimulation of motor cortex with F wave recording was used assess central motor conduction. time, (CMCT). and central somatoseusory conduction time(CSCT)was evaluated by SEPs in 20 pailents surffring from myeloP8thy of cervical spondylosis. Theresults were comapared with 20 control subjects. The results showed that CMCT of Patients was obviously prolonged then that of contral subjects, the sbnormal rate was 80% which was higher than70K of SEPs slid that the prolongation or CMCT had a good correlation with the severe degree ofmyelopathy. The Painless and noninvasive .magnetic stimulation of PEPs could figure out the compressed degree of motor descending pathway and was. useful technique for diagnosis of cervicalspondylotic myelopathy.

Machine learning-based detection of cervical spondylotic myelopathy using multiple gait parameters

Cervical spondylotic myelopathy(CSM)is the main cause of adult spinal cord dysfunction,mostly appearing in middle-aged and elderly patients.Currently,the diagnosis of this condition depends mainly on the available imaging tools such as X-ray,computed tomography and magnetic resonance imaging(MRI),of which MRI is the gold standard for clinical diagnosis.However,MRI data cannot clearly demonstrate the dynamic characteristics of CSM,and the overall process is far from costefficient.Therefore,this study proposes a new method using multiple gait parameters and shallow classifiers to dynamically detect the occurrence of CSM.In the present study,45 patients with CSM and 45 age-matched asymptomatic healthy controls(HCs)were recruited,and a three-dimensional(3D)motion capture system was utilized to capture the locomotion data.Furthermore,63 spatiotemporal,kinematic,and nonlinear parameters were extracted,including lower limb joint angles in the sagittal,coronal,and transverse planes.Then,the Shapley Additive exPlanations(SHAP)value was utilized for feature selection and reduction of the dimensionality of features,and five traditional shallow classifiers,including support vector machine(SVM),logistic regression(LR),k-nearest neighbor(KNN),decision tree(DT),and random forest(RF),were used to classify gait patterns between CSM patients and HCs.On the basis of the 10-fold cross-validation method,the highest average accuracy was achieved by SVM(95.56%).Our results demonstrated that the proposed method could effectively detect CSM and thus serve as an automated auxiliary tool for the clinical diagnosis of CSM.

Four Levels Anterior Cervical Discectomy and Fusion by Stand Alone PEEK Cages

Background: cervical spondylotic myelopathy is a common health problem that neurosurgeons face in Egypt. The aim of this study is to evaluate the efficacy of PEEK cage only in 4 levels anterior cervical discectomy as one of surgical option other than anterior cervical corpectomy, fixation by plat or posterior approach for cervical laminectomy, and assessment of post spinal surgery pain. Methods: this prospective study on 28 patients with cervical spondylotic myelopathy (CSM) over a period of 3 years (between April 2012 and April 2015) with mean period of follow up 30 months. We have done anterior cervical discectomy with fixation by cage only for all cases with perioperative assessment and scoring clinically and radiologically (Japanese Orthopaedic Association [JOA] scores, Visual Analogue Scale [VAS] scores for assessment of neck and arm pain, perioperative parameters (hospital stay, blood loss, operative time), the European Myelopathy Scoring (EMS) and Odom’s criteria, and the incidence of complication,post spinal surgery pain assessment). Results: clinical outcome was excellent (28.55), good (50%) and fair (21.5) according to Odom criteria. The European Myelopathy Scoring (EMS), improved from 10 to 16. The mean JOA score improved from 10.1 ± 2.1 to 14.2 ± 2.3. Fusion failure had been seen in 4 patients in one level for each secondary to anterior displacement of the cage with no other major complications. Conclusion: 4 levels anterior cervical discectomy with PEEK cage only is an effective, save and less costly with less post operative complication and hospital stay and less post spinal surgery pain.

Clinical application of anterior cervical decompression and fusion under METRx system

Objective: To explore the feasibility and effect of anterior cervical decompression and fusion under METRx system. Methods: Between Nov. 2001 and Nov. 2003, totally 23 consecutive patients were performed anterior cervical decompression and fusion under METRx system. The clinical outcome was evaluated by Odom standard. Results: Decompression and fusion along with internal fixation was obtained in all the 23 patients with minimal tissue damage and operation-caused scar. There were no wound infection, neurological injuries, throat discomfort and other complications. The total rate of excellent and good outcome in patients with degenerative cervical diseases was 94%. Conclusion: Cervical decompression and fusion can be performed under METRx system with its own advantages, such as minimal tissue damage and operation-caused scar, less throat discomfort.

Development and prospects of cervical laminoplasty

Cervical laminoplasty surgery is an alternative to laminectomy. It can increase the space of the spinal cord available by raising the lamina, and achieve the indirect decompression effect to treat cervical spondylosis. Various techniques of laminoplasty have since been developed after two prototype techniques: Hirabayashi's open-door laminoplasty and Kurokawa's double-door laminoplasty. Several studies report superior biomechanical stability of the cervical spine after laminoplasty compared with laminectomy. Recent development in laminoplasty is preservation of muscle attachment, which enabled dynamic and static stabilization of the cervical spine by neck extensor muscles. After treatment with new laminoplasty techniques with active postoperative neck muscle exercises, postoperative instability, kyphosis, axial neck pain, and loss of ROM become minimal. The development,complications and future trends of cervical laminoplasty are summarized below.

自稳式人工椎体在颈椎前路手术中的应用

目的:探讨自稳式人工椎体(artificial vertebral body,AVB)在颈前路椎体次全切除内固定融合手术(anterior cervical corpectomy and fusion,ACCF)中的短期应用效果。方法:遵循牛津IDEAL(Idea,Development,Exploration,Assessment,and Long-term Follow-up)方法学原则,采用单臂探索型研究的方法,纳入脊髓型颈椎病患者进行回顾性分析。所有患者均接受单节段ACCF手术,术中植入3D打印自稳式AVB,术后规律随访。采用日本骨科协会(Japanese Orthopedics Association,JOA)脊髓损害评分表评估手术前后神经功能改善情况,依据术后6个月的影像学测量数据评估融合情况。结果:共纳入11例病例,随访时间均超过6个月,手术时的平均年龄(57.2±10.2)岁,平均手术时间(76.1±23.1)min,中位出血量150(100,200)mL。术后无吞咽困难、血肿形成、神经功能损伤加重等并发症出现。至末次随访,JOA评分由术前的13.2±2.2恢复至末次随访时的16.3±0.8,恢复率为85.9%。假体平均沉降距离为(1.2±1.1)mm,1例假体出现超出3 mm的严重沉降(9.1%)。颈椎前凸角度较术前显著改变(P=0.013)。至术后6个月时,所有病例均实现融合。结论:自稳式AVB在单节段ACCF中的短期应用效果良好,融合率高,具有零切迹的优势,并发症少。

术前C7/T1椎间孔面积对后路单开门椎管扩大成形术治疗脊髓型颈椎病疗效的影响

目的:探究术前C7/T1椎间孔面积对脊髓型颈椎病患者接受后路单开门椎管扩大成形术疗效的影响。方法:回顾性分析2021年9月~2022年9月在我院因脊髓型颈椎病行后路单开门椎管扩大成形术治疗的76例患者,其中男58例、女18例,年龄为64.4±8.5岁。于患者术前颈椎双斜位X线片上测量C7/T1椎间孔面积,根据C7/T1椎间孔面积分为两组:A组,C7/T1椎间孔面积≤平均值(40例),B组,C7/T1椎间孔面积大于平均值(36例)。收集并比较两组患者的手术时间、术中出血量,两组患者的术前、术后3个月、术后12个月的JOA评分,计算JOA改善率;记录两组患者术后12个月的轴性症状发生情况,采用T检验、方差分析及卡方检验分析术前不同C7/T1椎间孔面积的患者接受颈后路单开门手术治疗后是否存在疗效的差异性。结果:C7/T1椎间孔面积A组为35.2±9.7mm^(2),B组为65.7±13.1mm^(2);术前C2~C7 Cobb角A组为14.0°±3.6°,B组为16.0°±5.5°,两组间椎间孔面积和C2~C7 Cobb角有统计学差异(P<0.05)。手术时间A组127.5±23.6min,B组120.3±32.6min;出血量A组176.8±88.2mL,B组183.6±100.2mL,两组间均无统计学差异(P>0.05)。术前JOA评分A组10.9±2.0分,B组10.3±2.1分,两组间无统计学差异(P>0.05)。术后3个月JOA评分A组12.8±1.5分,B组14.0±2.2分;术后12个月JOA评分A组14.1±1.5分,B组15.9±1.7分,两组间有统计学差异(P<0.05)。术后3个月、12个月JOA评分改善率两组间有统计学差异(P<0.05)。A、B两组术后12个月的轴性症状发生率分别为42.5%和19.4%,有统计学差异(P<0.05)。结论:术前C7/T1椎间孔面积较大的患者后路单开门椎管扩大成形术后神经功能的恢复更好,JOA改善率更高,术后轴性症状的发生率更低。

脊髓型颈椎病患者行颈后路椎板成形术后继发颈椎曲度丢失的风险因素

目的探讨脊髓型颈椎病患者行颈后路单开门椎板成形(cervical open-door expansive laminoplasty,LAMP)手术后的颈椎曲度丢失情况,并分析其相关因素。方法回顾性分析该院骨科于2018年1月~2020年1月开展LAMP手术(开门侧均采用微型钛板固定)的82例脊髓型颈椎病患者资料,评价患者术前、术后2年时的VAS评分、mJOA评分和改善率,并观察患者术前、术后2年时的C1-2Cobb角、C_(2-7)Cobb角、C_(2-7)屈曲和伸展ROM、C_(2-7)矢状位垂直距离(sagittal vertical axis,SVA)变化情况。对上述影像学指标之间的相关性、上述指标与VAS评分和mJOA评分改善程度的相关性,均采用Spearman相关性分析;采用多元线性回归分析,确定LAMP术后C_(2-7)Cobb角、C_(2-7)ROM减少和C_(2-7)SVA增加的风险因素。结果(1)与术前相比,所有患者LAMP术后2年的VAS评分显著降低(P<0.05)、mJOA评分显著升高(P<0.05),mJOA改善率达到(50.5±10.5)%;术后2年的C_(2-7)Cobb角和C_(2-7)ROM均显著减少,而C_(2-7)SVA显著增加(P<0.05)。(2)Spearman相关性分析显示,术后C_(2-7)Cobb角与T_(1)斜率和C_(2-7)屈曲ROM呈正相关性(r=0.223,r=0.386);术后C_(2-7)SVA值与C1-2Cobb角和T_(1)斜率呈正相关性(r=0.295,r=0.491),与术后C_(2-7)屈曲ROM呈负相关性(r=-0.325)。术后VAS改善程度、mJOA改善率与C_(2-7)Cobb角、C_(2-7)屈曲ROM和C_(2-7)SVA的变化值均无明显相关性(P>0.05)。(3)多元线性回归分析显示,术前T_(1)斜率越大,则术后C_(2-7)Cobb角减少越明显(β=0.331;P=0.007);术前C_(2-7)伸展ROM越大,则术后C_(2-7)Cobb角的减少越轻微(β=-0.312;P=0.022)。结论多节段脊髓型颈椎病患者行LAMP手术后,可出现颈椎曲度丢失、活动度减少和颈椎重心位置前移等变化,但尚未对术后早期疗效造成明显影响。术前颈椎伸展能力越大,术后颈椎曲度丢失越少;术前T_(1)斜率越大,则术后颈椎曲度丢失越明显。

Value of somatosensory evoked potentials in diagnosis, surgical monitoring and prognosis of cervical spondylotic myelopathy

Background The value of somatosensory evoked potentials （SEPs） in the diagnosis and prognosis of cervical spondylotic myelopathy, as well as the usefulness of monitoring intraoperative potentials in terms of safety and predictive factors were investigated. Methods Each of the 76 myelopathic patients underwent surgical intervention. According to the wave configurations of the SEPs, the cases were categorised into four groups： Type Ⅰ, Ⅱ, Ⅲ and Ⅳ. The clinical myelopathy disability was classified and the severity of neurological deficits was scored. Clinical function after surgery was evaluated. Preoperative potentials and intraoperative monitoring were categorized. The correlations between .evoked potentials detection, monitoring, myelopathy disability and surgical outcome in the different groups were discussed. Results According to the configurations of the SEPs, there were 27 patients （36%） of Type Ⅰ, 30 patients （39%） of Type Ⅱ, 8 patients （11%） of Type Ⅲ, and 11 patients （14%） of Type Ⅳ. The categorised evoked potentials were shown to be significantly associated with the clinical representation of myelopathy （P 〈0.01） and the recovery rate from identifiable SEPs waves （groups A, B and C） was significantly higher than unidentifiable waves （group D, P〈0.01）. A deterioration of SEPs was detected in 23 cases （30%）, whereas there was no change in 40 cases （53%） and improvements in 13 cases （17%）. A significant difference in recovery rates could be observed in various monitoring groups within the short-term follow-up period, while there were no obvious differences in the long-term follow-up groups. Conclusions SEP technique is a valuable and practical tool for the diagnosis, monitoring and prognosis of myelopathy. Classified evoked potentials are well correlated with cervical spondylotic myelopathy disability, and unidentifiable SEPs waves in patients are indicative of a relatively poor outcome. In addition, intraoperative monitoring of SEPs plays an important role in protecting neural structures during cervical spine surgery.

Comparison of Functional and Radiological Outcomes Between Two Posterior Approaches in the Treatment of Multilevel Cervical Spondylotic Myelopathy

Background：Posterior cervical decompression is an accepted treatment for multilevel cervical spondylotic myelopathy （CSM）.Each posterior technique has its own advantages and disadvantages.In the present study,we compared the functional and radiological outcomes of expansive hemilaminectomy and laminoplasty with mini titanium plate in the treatment of multilevel CSM.Methods：Forty-four patients with multilevel CSM treated with posterior cervical surgery in Department of Orthopedic Surgery,Beijing Army General Hospital from March 2011 to June 2012 were enrolled in this retrospective study.Patients were divided into two groups by surgical procedure：Laminoplasty （Group L） and hemilaminectomy （Group H）.Perioperative parameters including age,sex,duration of symptoms,opcrative duration,and intraoperative blood loss were recorded and compared.Spinal canal area,calculated using AutoCAD software（Autodesk Inc.,San Rafael,CA,USA）,and neurological improvement,evaluated with Japanese Orthopedic Association score,were also compared.Results：Neurological improvement did not differ significantly between groups.Group H had a significantly shorter operative duration and significantly less blood loss.Mean expansion ratio was significantly greater in Group L （77.83 ± 6.41%） than in Group H （62.72 ± 3.86%） （P 〈 0.01）.Conclusions：Both surgical approaches are safe and effective in treating multilevel CSM.Laminoplasty provides a greater degree of enlargement of the spinal canal,whereas expansive hemilaminectomy has the advantages of shorter operative duration and less intraoperative blood loss.