影响单开门椎管扩大成形术治疗颈椎病疗效的术后相关因素分析

目的 探讨单开门椎管扩大成形术治疗多节段脊髓型颈椎病术后因素对手术效果的影响.方法 回顾性分析2001年5月至2006年12月接受单开门椎管扩大成形术治疗的多节段脊髓型颈椎病患者.选取JOA改善率>75%(A组38例)和<25%的病例(B组32例)进行分析.对两组患者年龄、性别、病程、术前JOA评分、术前Pavlov比率、术前颈椎活动度、术前颈椎曲度指数、脊髓受压节段数、随访时间等可能影响术后JOA改善率的术前参数行统计学分析,两组只在年龄和术前JOA评分上差异有统计学意义.去除两组中年龄>60岁的病例以及JOA评分<6分的病例.A组剩余24例(A1组),B组18例(B1组).再次对A1组和B1组行以上统计学分析,两组各项参数差异均无统计学意义.对A1和B1两组术后颈椎活动范围及其改变率、术后颈椎曲度指数及其改变率、术后Pavlov比率及椎管扩大率等六项参数进行成组设计t检验,并与JOA改善率进行相关性分析.结果上述六项参数中除两组术后颈椎活动范围差异无统计学意义(P>0.05),其余五项参数差异均有统计学意义(P<0.05).A1组中除术后颈椎活动范围与JOA改善率无相关性,其余指标均与JOA改善率有相关性;B1组中除术后颈椎活动范围及其改变率与JOA改善率无相关性,其余各指标均与JOA改善率有相关性.结论 术后减小颈椎活动范围、维持颈椎前凸及尽量扩大椎管直径有利于神经功能的恢复.     

Segmental cervical instability does not drive the loss of cervical lordosis after laminoplasty in patients with cervical spondylotic myelopathy

BACKGROUND/CONTEXTKyphotic deformity after cervical laminoplasty (CLP) often leads to unfavorable neurological recovery due to insufficient indirect decompression of the spinal cord. Existing literature has described that segmental cervical instability is a contraindication for CLP because it is a potential risk factor for kyphotic changes after surgery; however, this has never been confirmed in any clinical studies.PURPOSETo confirm whether segmental cervical instability was an independent risk factor for postoperative kyphotic change and to examine whether segmental cervical instability led to poor neurological outcomes after CLP for cervical spondylotic myelopathy (CSM).STUDY DESIGN/SETTINGA retrospective studyPATIENT SAMPLEPatients who underwent CLP for CSM between January 2013 and January 2021 with a follow-up period of ≥1 year were enrolled.OUTCOME MEASURESCervical radiographic measurements including C2–C7 lordosis (C2–7 angle), cervical sagittal vertical axis, C7 slope, flexion range of motion (fROM) and extension ROM (eROM) were assessed using neutral and flexion-extension views. Segmental cervical instability was classified into anterolisthesis (AL) of ≥2 mm displacement, retrolisthesis (RL) of ≥2 mm displacement, and translational instability (TI) of ≥3 mm translational motion. The amount of C2–7 angle loss at the follow-up period compared to the preoperative measurements was defined as cervical lordosis loss (CLL). Neurological outcomes were assessed using the recovery rate of the Japanese Orthopedic Association score (JOA-RR).METHODSCLL was compared among patients with and without segmental cervical instability. Further, multiple linear regression model for CLL was built for the evaluation with adjustment of the reported risks, including cervical sagittal vertical axis, C7 slope, fROM, eROM, and patient age together with AL, RL, and TI, as independent variables. The JOA-RR was also compared between patients with and without segmental cervical instability.RESULTSA total of 138 patients (mean age, 68.7 years; 65.9% male) were included in the analysis. AL, RL, and TI were found in 12 (8.7%), 33 (23.9%), and 16 (11.6%) patients, respectively. Comparisons among the groups showed that AL led to greater CLL; however, RL and TI did not. Multiple linear regression analysis revealed that greater CLL is significantly associated with greater fROM and smaller eROM (regression coefficient [β]=0.328, 95% confidence interval: 0.178 to 0.478, p<.001; β=?0.372, 95% confidence interval: ?0.591 to ?0.153, p=.001, respectively). However, there were no significant statistical associations in the AL, RL, and TI. Whereas, patients with AL tended to exhibit lower JOA-RR than those without AL (37.8% vs. 52.0%, p=.108).CONCLUSIONSSegmental cervical instability is not the definitive driver for loss of cervical lordosis after CLP in patients with CSM; thus, is not a contraindication in and of itself. However, it is necessary to consider the indications for CLP, according to individual cases of patients with AL on baseline radiograph, which is a sign of poor neurological recovery.     

Alternating cervical laminoplasty for cervical spondylotic myelopathy

We present a novel method of performing an 'open-door' cervical laminoplasty. The complete laminotomy is sited on alternate sides at successive levels, thereby allowing the posterior arch to be elevated to alternate sides. Foraminotomies can be carried out on either side to relieve root compression. The midline structures are preserved. We undertook this procedure in 23 elderly patients with a spondylotic myelopathy. Each was assessed clinically and radiologically before and after their operation. Follow-up was for a minimum of three years (mean 4.5 years; 3 to 7). Using the modified Japanese Orthopaedic Association scoring system, the mean pre-operative score was 8.1 (6 to 10), which improved post-operatively to a mean of 12.7 (11 to 14). The mean percentage improvement was 61% (50% to 85.7%) after three years. The canal/vertebral body ratio improved from a mean of 0.65 (0.33 to 0.73) pre-operatively to 0.94 (0.5 to 1.07) postoperatively. Alternating cervical laminoplasty can be performed safely in elderly patients with minimal morbidity and good results.     

单开门椎管扩大椎板成形术联合侧块螺钉治疗脊髓型颈椎病伴颈椎不稳

目的:探讨单开门椎管扩大椎板成形术联合侧块螺钉治疗脊髓型颈椎病伴颈椎不稳的疗效。方法:2010年3月至2012年10月,采用单开门椎管扩大椎板成形术联合侧块螺钉治疗脊髓型颈椎病伴颈椎不稳患者25例,其中男18例,女7例;年龄57~68岁,平均57岁。记录术前及末次随访时的JOA评分,对患者临床症状改善进行分析。同时记录Cobb角及颈椎活动度,分析颈椎退变程度。结果:33例患者均获随访,时间18~36个月,平均25.6个月。出现脑脊液漏1例,切口脂肪液化1例,C5神经根麻痹4例,JOA评分由术前的5.2±2.1增加至末次随访时的11.3±2.4(P0.05),Cobb角由术前的(6.5±3.4)°提升至末次随访时的(13.2±4.9)°(P0.05)。颈椎活动度由术前的(30.4±9.2)°下降至末次随访时的(26.5±8.7)°(P0.05)。结论:单开门椎管扩大椎板成形术联合侧块螺钉治疗脊髓型颈椎病伴颈椎不稳疗效良好,具有适用范围广、牢固等优点,但要减少并发症的发生。     

Canal-expansive laminoplasty in 83 patients with cervical myelopathy

Summary We have reviewed 83 patients who had undergone canal-expansive laminoplasty for the treatment of cervical myelopathy between 1982 and 1991. The procedures used for laminoplasty were a Z-plasty in 35 patients, unilateral laminoplasty in 19, and sagittal splitting of the spinous processes in 29. At an average follow-up of more than two years and five months, there were no significant differences in clinical results among the three operations, and excellent or good results were obtained in more than 70% of the patients. However, Z-plasty was the least preferable because this procedure had the longest operating time and the greatest intraoperative blood loss. The sagittal splitting procedure is recommended in routine laminoplasty in order to avoid complications at the site of osteotomy, and to allow simultaneous posterior fusion to be easily performed.

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Résumé Nous avons suivi 83 patients traités par laminoplastie pour myélopathie cervicale entre 1982 et 1991. La technique opératoire utilisée a été la plastie en Z pour 35 de ces patients, l'ouverture unilatérale pour 19 et la section sagittale de l'apophyse épineuse pour les 29 autres. Avec un recul moyen supérieur à 2 ans 5 mois, nous n'avons pas observé de différences significatives entre ces trois méthodes quant aux résultats cliniques, qui sont excellents ou bons dans 70% des cas. La plastie en Z s'avère la technique la moins recommandable en raison d'une durée opératoire plus longue et d'une perte sanguine plus importante au cours de l'opération. La section sagittale spinale est conseillée comme intervention de routine du fait de sa sécurité et de la possibilité de réaliser simultanément une arthrodèse postérieure.

     

Clinical outcomes following cervical laminoplasty for 204 patients with cervical spondylotic myelopathy

Wang MY, Shah S, Green BA. Clinical outcomes following cervical laminoplasty for 204 patients with cervical spondylotic myelopathy.

Background

Laminoplasty is a well-recognized technique for decompressing the cervical spine in cases of spondylotic myelopathy and ossification of the posterior longitudinal ligament. This technique, originally popularized in Asia, is becoming more widespread, but to date there have been few reports of clinical series from North American centers.

Methods

Retrospectively we reviewed (1986-2001) 204 cases of open door laminoplasty. All patients presented with symptoms and magnetic resonance imaging (MRI) findings consistent with myelopathy secondary to multisegmental cervical stenosis with spondylosis and underwent decompression from C3 to C7. Improvement in myelopathy was assessed with the Nurick Score.

Results

Average age was 63 years (range 36 to 92). Follow-up averaged 16 months. Postoperatively, Nurick scores improved by 1 point in 78 patients, 2 points in 37 patients, 3 points in 7 patients, and 4 points in 5 patients; 74 patients experienced no improvement, and 3 patients deteriorated by one point. There was no statistical difference in myelopathy outcomes when comparing patients older and younger than 75 years of age. In two patients there was radiographic progression of kyphosis, but in no case was subsequent fusion required. Six patients without neck pain preoperatively developed new intractable neck pain after surgery.

Conclusions

Open door expansile laminoplasty is a safe and effective method for treating cervical spondolytic myelopathy. Laminoplasty is thus an alternative to anterior surgery that can be accomplished quickly with minimal blood loss, minimizing risks in elderly patients.     

Degenerative spondylolisthesis does not influence surgical results of laminoplasty in elderly cervical spondylotic myelopathy patients

The objective of the study was to investigate the comorbidity of degenerative spondylolisthesis (DS), in elderly cervical spondylotic myelopathy (CSM) patients in our hospital, and the correlation between surgical results and preoperative DS. There are few studies on the outcome of laminoplasty for CSM with DS. A total of 49 elderly patients (>65 years old) who eventually had surgical treatment for CSM were evaluated. A slippage displacement of more than 2.5 mm at least at one level was classified to have a positive DS on flexion/extension radiographs (DS group). A slippage displacement less than 1.0 mm was considered a negative DS (non-DS group). Seventeen patients who had slippage of 1.0–2.5 mm were excluded from the study. The DS group (n = 15) included cases with DS at preoperation, while the remaining cases (n = 17) belonged to the non-DS group. The flexion/extension radiographs of the two groups were compared for range of motion and clinical results at 3 years after the operation. Of all elderly patients, 30.6% had DS. There was no significant difference between the two groups based on the clinical results. The range of motion of all cervical spines (DS group and non-DS group) was significantly limited. However, there was no significant difference between the two groups. New postoperative DS appeared in four patients, of which two were from the DS group and two from the non-DS group. These data suggest that degenerative spondylolisthesis does not influence surgical results in elderly cervical spondylotic myelopathy patients.     

Expansive open-door laminoplasty for cervical spinal stenotic myelopathy

Although the operative results have been improving since the air drill was introduced for cervical laminectomy instead of an ordinary rongeur, post-laminectomy complications, such as postoperative fragility of the cervical spine to acute neck trauma, posterior spur formation at the vertebral body, and malalignment of the lateral curvature have still remained as unsolved problems. In order to avoid these disadvantages, a new surgical technique called "expansive open-door laminoplasty" was devised by the author in 1977, which is relatively easier, safer, and better than the ordinary laminectomy from the standpoint of structural mechanics of the cervical spine. The operative procedure is described in detail. Operative results in the patients with cervical OPLL, spondylosis, and canal stenosis were satisfactory, and optimal widening of the AP diameter of the spinal canal is considered to be over 4 mm. From this procedure a bilateral, open-door laminoplasty has been devised for extensive exploration at the intradural space.     

改良颈椎后路单开门椎管扩大成形术治疗多节段脊髓型颈椎病

目的:总结保留颈半棘肌肌止、C3椎板切除、C4～C7“锚定”单开门椎管扩大成形术治疗多节段脊髓型颈椎病的临床效果.方法:2009年1月～2011年10月,共对74例多节段脊髓型颈椎病患者采用保留颈半棘肌肌止、C3椎板切除、“锚定法”固定悬吊C4～C7椎板的单开门椎管扩大成形术治疗,其中57例患者获得随访,男31例,女26例,年龄50～71岁,平均63岁.术前JOA评分4～11分,平均8.5±2.0分,颈椎活动度23°～49°,平均37.4°±10.3°,颈椎曲度指数6.0％～22.0％,平均(13.9±7.4)％.观察患者术中和术后并发症发生情况;术后6个月复查颈椎X线片,测量颈椎曲度指数和颈椎活动度,观察颈椎曲度指数和颈椎活动度变化情况;末次随访时对患者神经功能进行JOA评分,计算神经功能改善率 结果:手术均顺利完成,手术时间50～110min,平均70min.术中出血150～600ml,平均230ml.术中无脊髓损伤、脑脊液漏等并发症发生.术后早期41例患者有颈痛,给予消炎镇痛治疗,术后3周内疼痛消失或明显缓解2例出现切口感染,经抗感染治疗并再次清创后切口延时愈合.9例有明显轴性症状,发生率为15.8％;6例出现C5神经根麻痹,给予甲基强的松龙、营养神经药物等治疗后症状明显缓解.随访6～32个月,平均13个月,术后6个月颈椎曲度指数为4.2％～21.1％,平均(11.3±8.1)％,较术前丢失(2.9±2.4)％;颈椎活动度为18°～46°,平均28.2°±10.8°,平均丢失8.2°±5.1°.患者神经功能均不同程度得到改善,末次随访时JOA评分为10～17分,平均13.8±2.3分,较术前明显提高(P＜0.05),神经功能改善率为29.0％～77.3％,平均(57.0±19.7)％.末次随访均未发现“再关门”现象.结论:保留颈半棘肌肌止、C3椎板切除、“锚定法”固定悬吊C4～C7椎板的单开门椎管扩大成形术可明显改善多节段脊髓型颈椎病患者的神经功能,手术操作简单,临床疗效满意.     

Flexibility and alignment of the cervical spine after laminoplasty for spondylotic myelopathy

Summary The long term effects of laminoplasty on cervical movement and alignment were investigated by radiography and CT scans in a study of 56 patients with multisegmental myelopathy who had undergone a C3 to C7 open-door laminoplasty. Follow up averaged 5.8 years. Satisfactory neurological improvement occurred in 73%. Cervical flexion decreased by 35% and extension by 57%; the decrease of both movement was statistically significant. Decreased vertebral slip, as well as slightly reduced lordosis, was seen after operation. Increase in measured canal size after operation and at follow up was 48% and 40%; 8% of the expanded canal size was lost at the last follow up. Expansive open-door laminoplasty leads to a better neurological prognosis in this group of patients, while maintaining an increase in canal size and preserving spinal stability.

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Résumé Les effets à long terme de la laminoplastie sur la mobilité et l'alignement du rachis cervical ont été étudiés par radiographie et tomodensitométrie. Le travail a porté sur 56 patients atteints de myélopathie spondylitique multisegmentaire, ayant subi une laminoplastie ouverte C3–C7 avec une greffe osseuse réalisant un espaceur autogène. Le recul est en moyenne de 5.8 ans (de 2 à 10.4) et les résultats ont montré une amélioration neurologique satisfaisante dans 73% des cas. La flexion était diminuée de 35% et l'extension de 57%. Cette diminution de la mobilité était statistiquement significative. On a également observé une réduction du glissement vertébral et une légère réduction de la lordose. L'augmentation de la taille du canal après l'intervention chirurgicale était de 48% et de 40% au dernier examen; à ce moment elle avait disparu dans 8% des cas. Les laminoplasties ouvertes étendues assurent un meilleur pronostic neurologique chez les patients atteints de spondylite multisegmentaire en maintenant la taille du canal et en préservant la stabilité vertébrale.

     

Risk factors associated with upper extremity palsy after expansive open-door laminoplasty for cervical myelopathy

Background contextPostoperative paresis, so-called C5 palsy, of the upper extremities is a common complication of cervical surgery. There have been several reports about upper extremity palsy after cervical laminoplasty for patients with cervical myelopathy. However, the possible risk factors remain unclear.PurposeTo investigate the factors associated with the development of upper extremity palsy after expansive open-door laminoplasty for cervical myelopathy.Study designA retrospective review of medical records.Patient sampleA total of 102 patients (76 men and 26 women) were eligible for analysis in this study. The mean age of the patients was 58.7 years (range 35–81 years). Sixteen patients (13 men and 3 women, average age 62.8 years) with palsy were categorized as Group P, and eighty-six patients (63 men and 23 women, average age 57.8 years) without palsy as Group C.Outcome measuresThe demographic data collected from both groups were age, sex, duration of symptoms, disease, and type of surgical procedure. Cervical curvature index, width of the intervertebral foramen (WIF) at C5, anterior protrusion of the superior articular process (APSAP), number of compressed segments, high–signal intensity zone at the level corresponding to C3–C5 (HIZ:C3–C5), and posterior shift of the spinal cord (PSSC) were also evaluated.MethodsUpper extremity palsy was defined as weakness of Grade 4 or less of the key muscles in the upper extremity by manual muscle test without any deterioration of myelopathic symptoms after surgery. Comparisons were made with screen for the parameters with significant differences, and then we further analyzed these parameters by logistic regression analysis (the forward method) to verify the risk factors of the upper extremity palsy.ResultsSignificant differences in diagnosis, the type of procedure, WIF, APSAP, and HIZ:C3–C5 were observed between the two groups. No statistical difference in PSSC between the groups was noted (2.06 vs. 2.53 mm, p=.247). In logistic regression analysis, ossification of the posterior longitudinal ligament (OPLL), cervical open-door laminoplasty together with posterior instrumented fusion (CLP+PIF), and WIF were found to be significant risk factors for postoperative upper extremity palsy.ConclusionsPatients with preoperative foraminal stenosis, OPLL, and additional iatrogenic foraminal stenosis because of CLP+PIF were more likely to develop postoperative upper extremity palsy. Attention should be given to the WIF determined on preoperative computed tomography of the C5 root. To prevent iatrogenic foraminal stenosis, appropriate distraction between spine segments should be provided during placement of the rod.     

选择性椎板成形术和传统椎板成形术治疗脊髓型颈椎病的中期疗效

目的对比选择性椎板成形术和传统椎板成形术治疗脊髓型颈椎病的中期疗效。方法回顾性分析2010年9月—2015年12月收治的130例脊髓型颈椎病(CSM)患者临床资料,其中67例采用选择性椎板成形术治疗(试验组),63例采用传统椎板成形术治疗(对照组)。记录并比较2组手术时间、术中出血量、并发症发生情况,以及手术前后双手10 s握拳次数、双手握力、日本骨科学会(JOA)评分、C_(2～7) Cobb角、C2～5 Cobb角、C_(5～7) Cobb角、C7倾斜角、T1倾斜角、C_(2～7)矢状位平衡(SVA)和K线角。结果试验组手术时间、术中出血量均少于对照组,差异有统计学意义(P 0.05)。2组患者末次随访时双手10 s握拳次数、双手握力及JOA评分均较术前改善,差异有统计学意义(P 0.05)。末次随访时,对照组C_(2～7) Cobb角较术前减小、C_(2～7) SVA较术前增大,而试验组无显著改变,2组相比差异有统计学意义(P 0.05)。末次随访时,试验组7例(7/67,10.4%)发生轴性症状,对照组20例(20/63,31.7%)发生轴性症状,试验组轴性症状发生率显著低于对照组,差异有统计学意义(P 0.05)。结论 2种术式治疗CSM中期临床疗效满意。选择性椎板成形术在保证手术疗效的前提下,可缩短手术节段,减少对颈后部肌肉韧带的损伤,降低术后轴性症状的发生率。     

颈后路单开门椎管成形术治疗脊髓型颈椎病

目的:观察颈后路单开门椎管扩大成形术对颈椎管狭窄合并钳夹型脊髓型颈椎病的临床效果和可行性。方法:采用颈后路椎管扩大成形术治疗颈椎管狭窄合并钳夹型脊髓型颈椎病30例,男19例,女11例,常规C3-C7减压,棘突打孔10号线固定在门轴侧侧块关节囊上12例,门轴侧C3、C5、C7侧块螺钉固定悬吊椎板18例,术前和术后通过日本骨科学会JOA评分(17分法)评估临床疗效。结果:30例均获得随访,随访时间6～76个月,平均25个月。按照JOA评分:优8例,良14例,可6例,差2例,优良率73.33%(22/30)。其中3例术后3个月内发生C4或C5神经根麻痹,经保守治疗痊愈。2例在2年内因疗效不佳再行前路手术。结论:颈后路单开门椎管扩大成形术治疗颈椎管狭窄合并钳夹型脊髓型颈椎病是一种简单、有效可行的方法,尤其适应于老年人。     

Long-term results of double-door laminoplasty for cervical stenotic myelopathy

STUDY DESIGN: A retrospective study of the long-term results from double-door laminoplasty (Kurokawa's method) for patients with myelopathy caused by ossification of the posterior longitudinal ligament and cervical spondylosis was performed. OBJECTIVE: To know whether the short-term results from double-door laminoplasty were maintained over a 10-year period and, if not, the cause of late deterioration. SUMMARY OF BACKGROUND DATA: There are few long-term follow-up studies on the outcome of laminoplasty for cervical stenotic myelopathy. METHODS: In this study, 35 patients with cervical myelopathy caused by ossification of the posterior longitudinal ligament in the cervical spine and 25 patients with cervical spondylotic myelopathy, including 5 patients with athetoid cerebral palsy, underwent double-door laminoplasty from 1980 through 1988 and were followed over the next 10 years. The average follow-up period was 153 months (range, 120-200 months) in patients with ossification of the posterior longitudinal ligament and 156 months (range, 121-218 months) in patients with cervical spondylotic myelopathy. Neurologic deficits before and after surgery were assessed using a scoring system proposed by the Japanese Orthopedic Association (JOA score). Patients who showed late deterioration received further examination including computed tomography scan and magnetic resonance imaging of the cervical spine. RESULTS: In 32 of the patients with ossification of the posterior longitudinal ligament and 23 of the patients with cervical spondylotic myelopathy, myelopathy improved after surgery. The improvement of Japanese Orthopedic Association scores was maintained up to the final follow-up assessment in 26 of the patients with ossification of the posterior longitudinal ligament and 21 of the patients with cervical spondylotic myelopathy. Late neurologic deterioration occurred in 10 of the patients with ossification of the posterior longitudinal ligament an average of 8 years after surgery, and in 4 of the patients with cervical spondylotic myelopathy, including the 3 patients with athetoid cerebral palsy, an average of 11 years after surgery. The main causes of deterioration in patients with ossification of the posterior longitudinal ligament were a minor trauma in patients with residual cervical cord compression caused by ossification of the posterior longitudinal ligament and thoracic myelopathy resulting from ossification of the yellow ligament in the thoracic spine. CONCLUSIONS: The short-term results of laminoplasty for cervical stenotic myelopathy were maintained over 10years in 78% of the patients with ossification of the posterior longitudinal ligament, and in most of the patients with cervical spondylotic myelopathy, except those with athetoid cerebral palsy. Double-door laminoplasty is a reliable procedure for individuals with cervical stenotic myelopathy.     

Preoperative instability does not influence the clinical outcome in patients with cervical spondylotic myelopathy treated with expansive laminoplasty

Sixty-seven patients with cervical spondylotic myelopathy treated with expansive laminoplasty were retrospectively reviewed at a minimum 2-year follow-up. This study was designed to evaluate whether preoperative instability influences the clinical outcome in patients with cervical spondylotic myelopathy treated with laminoplasty without spinal fusion. Patients with preoperative instability were older and had shorter durations of symptoms prior to surgery than those without the instability. There were no significant differences in prevalence of axial symptoms, neurologic recovery, or radiologic findings between patients with and without preoperative cervical instability. At follow-up, the cervical range of motion was limited to 43.5% of the preoperative range, and no cervical instability was observed in any patients. Preoperative instability does not influence the clinical outcome and can be ignored if expansive laminoplasty is indicated for patients with cervical spondylotic myelopathy.     

Enlargement of cervical spinal cord correlates with improvement of motor function in upper extremities after laminoplasty for cervical myelopathy

OBJECTIVE: The correlation between postoperative spinal cord enlargement at the most compressive disc level and clinical outcome is controversial. The relationship between spinal cord enlargement at neurologically symptomatic disc level and clinical recovery has not been explored. The purpose of this study was to clarify the relationship between postoperative spinal cord enlargement at neurologically symptomatic disc level and neurologic outcome. METHODS: We studied 55 consecutive patients between 1995 and 2002. All patients underwent preoperative neurologic examination to determine the neurologically symptomatic disc level of the spinal cord and computed tomographic myelography twice before and 4 weeks after laminoplasty. The cross-sectional areas of both spinal cord and dural sac from C3/4 to C7/T1 disc levels were measured on computed tomographic myelography images. The Japanese Orthopedic Association scoring system was used for clinical evaluation before and 1 year after surgery. RESULTS: Total score improved significantly from 10.2+/-2.8 (SD) to 13.0+/-3.0 after operation. Motor and sensory function scores of upper and lower extremities also improved significantly. The enlargement of spinal cord area at the neurologically symptomatic disc level correlated significantly with improvement in motor function scores of upper extremities (rs=0.421 P=0.0052). However, there were no significant relationships between the enlargement of the spinal cord at the most compressive disc level or that at the dural sac and any categories of Japanese Orthopedic Association scoring system. CONCLUSION: Postsurgical enlargement of the cervical spinal cord at the neurologically symptomatic disc level at 4 weeks postoperatively correlated with recovery of motor function of the upper extremities at 1 year.