Surgical management of lumbar spinal stenosis

Eighty consecutive patients with lumbar spinal stenosis surgically treated during a 5-year period by the author were reviewed. Patients were placed in the following categories: lateral spinal stenosis (10), central-mixed stenosis (29), spinal stenosis after laminectomy and/or fusion (32), and spinal stenosis with degenerative scoliosis (9). Contrast-enhanced computed tomographic (CT) scans were helpful in determining the levels requiring decompression. However, in the multiply operated patient, contrast-enhanced CT scans were misleading in six patients. Patients with lateral spinal stenosis were treated with unilateral laminectomy and partial facetectomy. The 29 patients with central-mixed stenosis underwent decompressive laminectomy and bilateral facetectomies. Six fusions were done. In the nine patients with spinal stenosis and scoliosis, concaveside partial facetectomies and laminectomies were done as well as spinal fusions. The 32 patients with spinal stenosis after previous laminectomy and spinal fusions were the most difficult group to analyze, and their treatment was the least standardized. There were 19 good, eight fair, and five poor results in those who had undergone previous surgery. Fifty-seven of the 80 patients (71%) experienced a good result from their surgical treatment.     

Lumbar spinal stenosis: surgical considerations

Spinal stenosis is an acquired or congenital narrowing of the spinal or nerve-root canals. Surgical treatment is often effective. Acquired spinal stenosis most commonly occurs in those with degenerative disk disease and arthritic facets. If the degenerative process stabilizes and there is adequate room to accommodate the neural contents, symptomatic patients become asymptomatic. Residual stability after decompression must be assessed in patients having multilevel decompression. Fusion maybe indicated. In women with osteoporosis coexisting with degenerative scoliosis and spinal stenosis, decompression for concave nerve-root compression and fusion are necessary. Spinal fusion is not indicated in patients with lumbar spinal stenosis having unilateral decompression for lateral stenosis. Patients with central-mixed stenosis may not need fusion. Patients with spinal stenosis after laminectomies and diskectomies had better results when arthrodesis was done in conjunction with repeated decompression. Arthrodesis with instrumentation and decompression is recommended for patients with degenerative spondylolisthesis.     

后路椎间盘镜治疗腰椎间盘突出症和腰椎管狭窄临床应用

目的 评价椎间盘镜在腰椎间盘突出症和腰椎管狭窄中的应用价值。方法 应用椎间盘镜行椎间盘摘除术188例,其中38例行侧隐窝减压术。结果 平均随访6．9个月,手术优良率为97．4％(Macnab’s标准)。结 论椎间盘镜治疗腰椎间盘突出症和腰椎管狭窄近期疗效满意。     

伴有侧凸畸形的腰椎管狭窄症的外科治疗

目的总结后路一期减压、内固定、融合手术治疗伴有腰椎侧凸畸形的腰椎管狭窄症患者的效果。方法自1998年1月-2005年10月,治疗伴有腰椎侧凸畸形的腰椎管狭窄症患者38例,腰椎侧凸畸形角度平均31°,术前 JOA评分平均11分,均采用腰椎后路一期减压、矫形、内固定、融合治疗。结果 32例得到随访,随访时间1-4年,平均2．5年,矫正角度平均13°。矫正角度丧失1°-5°,平均3°。截骨融合率100％。随访时JOA评分平均23分,患者对手术效果满意。结论后路一期减压、内固定、融合手术是治疗伴有腰椎侧凸畸形的腰椎管狭窄症的有效手段。     

腰椎间盘手术失败原因分析和治疗

目的：对腰椎间盘手术失败的原因进行分析。方法：对129例腰椎间盘初次术后疗效不满意患者分析其原因，结果：在129列术后疗效不满意的患者中，需要再手术治疗的有98例（75．9％），初次手术失败的常见原因有椎间盘摘除不彻底或复发，保并有腰椎管狭窄（侧隐窝）狭窄的患者失能同时进行彻底地椎管减压、远期继发腰椎不稳以及选择了一些不恰当的手术病例等有关。结论：腰椎间盘术后症状复发原因较多，应充分结合患者的临床表现及影像学检查，严格掌握手术适应证。再手术目的的是解除疼痛，恢复功能，包括彻底减压和腰椎稳定性手术。     

"开窗技术"治疗退行性腰椎管狭窄症融合指征

目的 探讨初次"开窗技术"治疗退行性腰椎管狭窄症融合的指征.方法 对1999年12月至2005年12月收治的145例退行性腰椎管狭窄症患者进行回顾性研究.按术前腰椎条件及手术方法分三组:A组39例,术前合并腰椎失稳运动、退变性滑脱或侧弯,行融合术;B组31例,术前合并腰椎失稳运动、退变性滑脱或侧弯,行非融合术;c组75例,术前无腰椎失稳运动、退变性滑脱或侧 弯,行非融合术.对患者住院天数、手术时间、估计出血量复发、再手术及并发症情况等进行统计分析;采用Oswestry 功能障碍指数(ODI)和疼痛视觉模拟评分(VAS)及满意率等进行疗效评估,并进行统计学分析.结果 所有患者随访时间均在3年以上.C组的住院时间少于A组和B组(P<0.05);A组的手术时间和估计出血量均大于B组和c组,差异均有统计学意义(P<0.05);A、C组长 期疗效优于B组(P<0.05),而A、c两组间差异无统计学意义;三组间的复发或残余症状恶化、再手术及并发症等方面差异没有统计学意义.结论 对于术前合并腰椎失稳、滑脱或侧凸的退变性腰椎管狭窄症患者,即使初次行"开窗技术"减压,也应融合;单纯狭窄患者初次手术则无需融合.     

Diagnosis and therapy of the narrow lumbar spinal canal

In 30%-40% of the patients who are operated on for herniation of lumbar discs, osseous stenosis plays a certain role. However, only in one-third of them are special operative measures such as laminectomy necessary with or without additional lumbar fusion. When spondylodesis is carried out after laminectomy it is often combined with metal implant, which can drastically reduce the time a patient requires perioperative treatment. In younger patients showing typical signs of nerve root compression due to osseous stenosis of lateral recess, only segmental decompression in the form of foraminotomy is done. On the other hand, in cases of narrow spinal canal, which is found in elderly patients, neurogenic intermittent claudication is the predominant clinical picture. Kyphosis, scoliosis, and vertebral displacement can lead to local spinal stenosis. On addition, local pressure and tension on unstabile segments in combination with secondary fibrosis can lead to compression of the neural structures. The diagnosis is based on the clinical history and myelography. Computed tomography helps reveal the presence of herniation of a lumbar disc, which should be simultaneously operated upon. For the operative treatment there is no age limit. All in all, the operative results are so good that one is inclined to decide in favour of operation.     

Clinical and radiographic results of expansive lumbar laminoplasty in patients with spinal stenosis

BACKGROUND: In 1981, we developed a technique of expansive lumbar laminoplasty to alleviate the problems of conventional laminectomy in the treatment of spinal stenosis. The purposes of this study were to assess the long-term outcome following expansive lumbar laminoplasty and to investigate the postoperative problems. METHODS: Fifty-four patients underwent expansive lumbar laminoplasty for the treatment of spinal stenosis. There were forty-three men and eleven women with a mean age of 52.6 years. The average length of follow-up was 5.5 years. Preoperatively, twenty-five patients had degenerative stenosis; thirteen, stenosis due to spondylolisthesis; twelve, combined stenosis (disc herniation and stenosis); and six, hyperostotic stenosis. (Two patients with hyperostotic stenosis and spondylolisthesis were included in both groups.) The clinical results were assessed with use of the Japanese Orthopaedic Association score, and the rate of recovery was calculated. Radiographic findings were analyzed on the basis of the cross-sectional area of the spinal canal, kyphosis, range of motion of the lumbar spine, and the rate of interlaminar fusion. RESULTS: The average recovery rate at the time of the last follow-up was 69.2% for patients with degenerative stenosis, 66.5% for patients with combined stenosis, 65.2% for those with hyperostotic stenosis, and 54.7% for those with spondylolisthesis. The factors resulting in a poor recovery were an older age and insufficient decompression of the lateral stenosis. During the follow-up period, the Japanese Orthopaedic Association score became worse for seven patients, six patients had lesions develop at the level adjacent to the laminoplasty, and five patients had spondylolisthesis develop. Interlaminar fusion was observed in twenty-two patients (41%). CONCLUSIONS: The satisfactory results of expansive lumbar laminoplasty were maintained at an average of 5.5 years after surgery. The best indications for the lumbar laminoplasty procedure were young and active patients with central spinal stenosis.     

Coflex系统治疗退行性腰椎管狭窄症

 目的 探讨Coflex系统治疗退行性腰椎管狭窄症的初步临床疗效。
方法 2008年3月至2009年8,采用腰椎后路椎管减压棘突间植入Coflex系统治疗退行性腰椎管狭窄症患者26例,男11例,女15例;年龄45～78岁,平均65.4岁。L_3,4节段7例,L_4,5节段13例,L_3,4合并L_4,5节段6例。术前MRI和CT扫描证实L_3,4和（或）L_4,5节段黄韧带增厚,关节突关节骨质增生,合并椎间盘突出致中央椎管及侧隐窝狭窄,神经根或马尾受压。应用eFilm及CAD软件测量术前及术后3个月、12个月手术节段椎间隙前缘高度、后缘高度、活动度,术前、术后椎管面积;采用日本骨科学会评分标准（Japanese Orthopaedic Association,JOA）进行功能评估。
结果 全部病例随访12～24个月,平均15个月。术后患者腰腿疼痛症状均明显缓解,日常生活能力改善。JOA评分由术前平均（15.46±4.30）分改善至术后3个月（24.50±1.58）分,责任节段椎管面积由术前平均（218.4±16.2）mm 2增加至术后（264.6±9.9）mm 2。单节段椎间隙前缘高度无明显变化,椎间隙后缘高度较术前增加,随时间延长高度有所下降。术后手术节段仍保留一定的活动度,但较术前明显下降。Coflex系统无松动、断裂及脱出。
结论 Coflex系统治疗退行性腰椎管狭窄症可较好地维持相应节段的稳定性,安全可行,近期疗效满意。     

Clinical study of lumbar spinal canal stenosis on 70 operated cases --clinical symptoms, pathogenesis, operative method, postoperative results

In surgical treatment of lumbar spinal canal stenosis, the stenotic area related to the clinical symptoms was determined and the stenotic form and stenotic factors in this stenotic area were estimated before operation. The most appropriate decompression of the stenotic area was performed taking the stenotic form into consideration and retaining the spinous process and interspinous ligament. In cases of stenosis of the spinal canal, posterolateral decompression of the dural sheath was performed by means of resection of the medial edge of the bilateral inferior articular processes and the yellow ligaments. In cases of stenosis of the spinal canal associated with stenosis of the lateral recess, the root was decompressed by unroofing the lateral recess in addition to posterolateral decompression of the dural sheath. And in cases with stenosis of the lateral recess, the root in an affected area was decompressed. Neither operation on the intervertebral disc nor incision of the dural sheath was performed. After operation as described above, symptoms, operative findings and postoperative results were investigated in 70 cases which could be directly examined. In this paper we discuss the relationship between the symptoms and the stenotic area, stenotic forms and stenotic factors. When our postoperative results were compared with those of cases with extensive laminectomy, it was seen that none of the patients we treated had low back pain nor recurrence of intermittent claudication and that lessening of paralysis was sufficient.     

Lumbar spinal stenosis. Treatment strategies and indications for surgery

Initially, all patients with degenerative lumbar spinal stenosis should be treated conservatively. Rapid deterioration is unlikely. The majority of patients may either improve or remain stable over a long-term follow-up with nonoperative treatment. Surgery should be an elective decision by the patients who fail to improve after conservative treatment. Medical evaluation is mandatory in those elderly patients with frequent comorbidities. For central spinal stenosis, without significant grade I spondylolisthesis or deformity, decompression is the surgical treatment of choice. Iatrogenic instability must be avoided during decompression surgery by preserving the facet joint and the pars interarticularis. Limited decompression with laminotomy may be indicated for lateral canal stenosis. A limited decompression may avoid postoperative instability but is associated with more frequent neurologic sequelae. Postlaminectomy instability is uncommon, and too little decompression is a more frequent mistake than too much. Decompression is usually associated with good or excellent outcome in 80% of patients. Deterioration of initial post-operative improvement may occur over long-term follow-up. When spinal stenosis is associated with instability, degenerative spondylolisthesis, deformity, postoperative instability, or recurrent stenosis, fusion is often recommended. Instrumentation often improves the fusion rate but does not influence the clinical outcome. Generous decompression but selective fusion of the unstable segment only are preferable for degenerative spondylolisthesis and type I degenerative scoliosis with minimal rotation of the spine.     

Usefulness of Posner's definition of spinal instability for selection of surgical treatment for lumbar spinal stenosis

The aim of this study was to determine the usefulness of Posner's definition of spinal instability for selection of surgical therapy for lumbar spinal stenosis. Sixty patients with lumbar spinal stenosis were studied. Thirty-three patients were found to have instability, as defined using Posner's method. Nineteen of the 33 patients with instability underwent decompression and instrumented fusion. The 14 remaining patients with instability underwent decompression alone. Twenty-seven patients without instability were treated by decompression alone. Patients treated by decompression and fusion obtained the best results. Good results also could be obtained by decompression alone only if patients did not have instability. However, patients treated by decompression alone in the presence of instability had the worst results. The Posner's definition of instability proved useful for selecting patients with instability for fusion treatment.     

腰椎退变性侧凸的治疗策略

目的探讨非手术治疗或腰椎后路减压、矫形固定、融合手术治疗由于椎间盘退变后继发小关节退变、椎管和神经根管容积变化以及脊柱失稳、畸形等病理改变导致的腰椎退变性侧凸患者的效果。方法2001年7月-2007年6月，治疗退变性腰椎侧凸患者56例，其中行非手术治疗5例。手术治疗51例。手术组患者平均年龄为63岁，腰椎侧凸Cobb角平均30°，采用腰椎后路减压，或辅助椎弓根螺钉矫形固定、后外侧融合或椎间融合治疗。结果56例均得到随访，平均随访时间为20个月，非手术治疗和手术患者均对治疗效果满意，生活质量提高，手术组矫正角度平均为15°，骨融合率达到95％，无神经损伤及翻修病例。结论腰椎退变性侧凸首选非手术治疗，如失败应根据患者情况遵循尽量采用有限内固定和融合的原则行手术治疗。     

Pedicle fat grafts for the prevention of scar in low-back surgery. A preliminary report on the first 92 cases

Encouraged by the results of an experimental study on dogs, the authors performed pedicle fat grafts in 92 patients. The grafts were used in the following groups of patients: following primary disc removal (37 cases); following scar removal in the multiply operated back with definite root findings (37 cases); in patients with spondylolisthesis who had had prior decompressions but developed fifth lumbar nerve root pain after lateral fusion (6 cases); in three patients with spondylolisthesis and simple decompression; in nine patients with spinal stenosis. Pedicle fat grafts were obtained from the subcutaneous layer of fat of the low back in 85 patients and from the buttocks in seven patients. The grafts were brought through openings in the fascia and muscle and were used to cover the dural sac as well as the margins of the nerve root. They were held in position by a fine suture of silk. The results after a minimum follow-up of 1 year and a maximum of 4 years have been excellent or good in 66 percent of the patients who have had lateral fusion with resultant L5 root compression, in 99 percent of patients with spondylolisthesis and decompression only, and in 66 percent of patients with spinal stenosis. The results in the other two groups compare favorably with those reported in the literature.     

Revision after spinal stenosis surgery

To make a literature review on spinal stenosis recurrence after a first surgery and edit rules to avoid this complication. We conducted two separate PUBMED searches to evaluate the revision post-stenosis and degenerative scoliosis surgery using the terms: lumbar vertebrae/surgery, spinal stenosis, spine, scoliosis and reoperation. The resulting papers were categorized into three groups: (1) those that evaluated reoperation post-simple decompression; (2) those that evaluated spinal decompression and fusion for short (3 levels or less) or long (more than 3 levels) segment spinal fusion; and (3) those diagnosing the stenosis during the surgery. (1) We found 11 relevant papers that only looked at revision spine surgery post-laminectomy for spinal stenosis. (2) We found 20 papers looked at reoperation post-laminectomy and fusion amongst which there were two papers specifically comparing long-segment (> 3 level) and short-segment (3 or less levels) fusions. (3) In the unspecified group, we found only one article. Fifteen articles were excluded as they were not specifically looking at our objective criteria for revision surgery. In regard to revision post-adult deformity surgery, we found 18 relevant articles. After this literature review and analysis of post-operative stenosis, it seems important to provide some advice to avoid revision surgeries more or less induced by the surgery. It looks interesting when performing simple decompression without fusion in the lumbar spine to analyse the risk of instability induced by the decompression and facet resection but also by a global balance analysis. Regarding pre-operative stenosis in a previously operated area, different causes may be evocated, like screw or cage malpositionning but also insufficient decompression which is a common cause. Intraoperatively, the use of neuromonitoring and intraoperative CT scan with navigation are useful tool in complex cases to avoid persisting stenosis. Pre-op analysis and planning are key parameters to decrease post-op problems. These slides can be retrieved under Electronic Supplementary Material.     

下腰椎内固定融合手术后复发性腰痛及下肢放射痛23例原因分析

目的分析椎弓根螺钉内固定下腰椎融合手术后腰痛原因。方法随访2001年1月~2003年12月采用椎弓根螺钉内固定下腰椎融合手术103例,男43例,女60例;腰椎滑脱28例,腰椎管狭窄54例,腰椎间盘突出症21例。随访时进行问卷调查及X线、CT或MRI检查,并分析手术后腰痛的可能原因。结果随访时间3~5年,疗效优良80例(77.7%);术后有明显腰痛或腰痛伴下肢放射痛23例(22.3%)。邻近节段疾病11例(2节段融合7例,1节段融合4例;10.7%),内固定使用不当3例,椎弓根螺钉断裂2例,减压不完全2例,高位椎间盘突出1例,不明原因4例。结论邻近节段疾病、内固定使用不当、内固定失败是复发性腰痛主要原因。原有退变基础、减压范围超过融合节段、融合节段的长短都是产生邻近节段疾病的重要的危险因素。     

Spinaplasty following lumbar laminectomy for multilevel lumbar spinal stenosis to prevent iatrogenic instability

Background:

Iatrogenic instability following laminectomy occurs in patients with degenerative lumbar canal stenosis. Long segment fusions to obviate postoperative instability result in loss of motion of lumbar spine and predisposes to adjacent level degeneration. The best alternative would be an adequate decompressive laminectomy with a nonfusion technique of preserving the posterior ligament complex integrity. We report a retrospective analysis of multilevel lumbar canal stenosis that were operated for posterior decompression and underwent spinaplasty to preserve posterior ligament complex integrity for outcome of decompression and iatrogenic instability.

Materials and Methods:

610 patients of degenerative lumbar canal stenosis (n=520) and development spinal canal stenosis (n=90), with a mean age 58 years (33–85 years), underwent multilevel laminectomies and spinaplasty procedure. At followup, changes in the posture while walking, increase in the walking distance, improvement in the dysesthesia in lower limb, the motor power, capability to negotiate stairs and sphincter function were assessed. Forward excursion of vertebrae more than 4 mm in flexion–extension lateral X-ray of the spine as compared to the preoperative movements was considered as the iatrogenic instability. Clinical assessment was done in standing posture regarding active flexion–extension movement, lateral bending and rotations

Results:

All patients were followed up from 3 to 10 years. None of the patients had neurological deterioration or pain or catch while movement. Walking distance improved by 5–10 times, with marked relief (70–90%) in neurogenic claudication and preoperative stooping posture, with improvement in sensation and motor power. There was no significant difference in the sagittal alignment as well as anterior translation. Two patients with concomitant scoliosis and one with cauda equine syndrome had incomplete recovery. Two patients who developed disc protrusion, underwent a second operation for a symptomatic disc prolapse.

Conclusion:

Spinaplasty following posterior decompression for multilevel lumbar canal stenosis is a simple operation, without any serious complications, retaining median structures, maintaining the tension band and the strength with least disturbance of kinematics, mobility, stability and lordosis of the lumbar spine.     

An endoscopic curved Kerrison rongeur for spinal stenosis surgery.

OBJECTIVE: Adequate neural decompression with minimal structural alteration is the goal of lumbar stenosis surgery. Often because of limited visualization significant parts of the facet joints are removed enhancing the potential for developing instability. To overcome this problem we have developed a small curved Kerrison rongeur that contains a 10 000-pixel endoscope. This instrument allows one to visualize and decompress structures within the lateral recess that may have required more extensive removal of portions of the facet joints. METHODS: Ten patients with symptomatic lumbar spinal stenosis were decompressed using the endoscopic rongeur. RESULTS: Compression of the lateral dura and nerve root by the facet and ligamentum could easily be identified. In all cases the ligament could be easily removed and the facet joint was undercut only enough to decompress the nerve. CONCLUSION: This instrument has the potential for less invasive decompression of spinal stenosis and further study of its utility is planned.     

Expansive lumbar laminoplasty for degenerative spinal stenosis in patients below 70 years of age

We reviewed the clinical and radiological results of patients with lumbar degenerative spinal stenosis who underwent expansive laminoplasty with a mean follow-up term of 5.6 years. Twenty-seven patients underwent open-door-type expansive lumbar laminoplasty, which has both decompression and stabilization effects. Clinical results were assessed based on the score system devised by the Japanese Orthopaedic Association (JOA score). The number and causes of repeat surgery were also evaluated. Radiological changes, such as degenerative scoliosis and spondylolisthesis, were evaluated at the operated levels and at levels Ll–L5. There was marked recovery of clinical symptoms assessed by pre- and postoperative JOA score. Nearly 80% of patients obtained good or excellent results. Only one patient (4%) required additional surgery, which involved discectomy at the caudal level of the laminoplasty. Radiographic evaluation revealed that postoperative changes of spondylolisthesis and scoliosis were slight both in the expanded area and the Ll–L5 levels. Range of motion of the disc space angle in the expanded area showed a significant decrease postoperatively. However, pre- and postoperative radiological changes showed no significant correlation with JOA score changes and repeat surgery. In conclusion, lumbar fusion after posterior decompression in active patients with spinal stenosis offers satisfactory clinical results concomitantly with a relatively small risk of repeat surgery.     

经椎间孔入路治疗腰椎侧隐窝狭窄症的疗效

目的探讨经皮内镜下椎间孔入路治疗腰椎侧隐窝狭窄症的临床疗效。方法对32例腰椎侧隐窝狭窄伴或不伴腰椎间盘突出患者采用经皮内镜下椎间孔入路行侧隐窝减压伴或不伴髓核摘除手术。术后1、3个月采用VAS评分评估患者腰腿痛改善情况,术后6个月采用改良MacNab评分标准评估疗效。结果32例患者均顺利完成手术,随访6个月。VAS评分术前为8~10(9.18±0.71)分,术后1个月为0~3(1.29±0.67)分,术后3个月为0~2(1.51±0.49)分,术后1、3个月与术前比较差异均有统计学意义(P<0.05)。术后6个月改良MacNab评分优良率为93.75%(30/32)。无感染、医源性神经根损伤、硬膜撕裂等并发症发生。结论经皮内镜下椎间孔入路治疗腰椎侧隐窝狭窄症能获得满意疗效。