Discitis and isthmic spondylolisthesis: a case report

Spondylolysis and spondylolisthesis are common causes of low back pain in children and adolescents. Disc space infection is less common, but is another cause of severe back pain in this population. The combination of both processes in the same segment is rare. This case report is of a 13-year-old patient with isthmic lumbosacral spondylolisthesis and disc space infection at the same level. A patient who presented with severe low back pain and a radiological picture of isthmic slip with end plate irregularities and anterior bridging osteophyte was diagnosed with disc space infection at the slip level. He was managed with intravenous antibiotics for 6 weeks, followed by oral medication for an additional 2 weeks. At follow-up 28 weeks later, a spontaneous radiological fusion at the slip level was noted with complete relief of his symptoms. The patient was able to resume sports activities. In conclusion, isthmic spondylolisthesis and disc space height infection might coexist. Nonoperative treatment will usually result in spontaneous fusion and the complete relief of symptoms.     

The long-term effect of posterolateral fusion in adult isthmic spondylolisthesis: a randomized controlled study.

BACKGROUND: Today there is some evidence-based medicine support for a positive short-term treatment effect of fusion in chronic low back pain in spondylolisthesis and in nonspecific degenerative lumbar spine disorders. The long-term effect is, however, unknown. PURPOSE: To determine the long-term outcome of lumbar fusion in adult isthmic spondylolisthesis. STUDY DESIGN: Prospective, randomized controlled study comparing a 1-year exercise program with instrumented and non-instrumented posterolateral fusion with average long-term follow-up of 9 years (range, 5-13). PATIENT SAMPLE: 111 patients aged 18 to 55 years with adult lumbar isthmic spondylolisthesis at L5 or L4 level of all degrees, and at least 1-year's duration of severe lumbar pain with or without sciatica. OUTCOME MEASURES: Pain and functional disability was quantified by pain (VAS), the Disability Rating Index (DRI), the Oswestry Disability Index (ODI) work status, and global assessment of outcome by the patient into much better, better, unchanged or worse. Quality of life was assessed by the SF-36. METHODS: The patients were randomly allocated to treatment with 1) a 1-year exercise program (n=34), 2) posterolateral fusion without pedicle screw instrumentation (n=37), or 3) posterolateral fusion with pedicle screw instrumentation (n=40). Long-term follow-up was obtained in 101 (91%) patients. Nine patients in the exercise group were eventually operated on. RESULTS: Longitudinal analysis: At long-term follow-up pain and functional disability were significantly better than before treatment in both surgical groups. No significant differences were observed between instrumented and non-instrumented patients in any variable studied. In the exercise group the pain was significantly reduced but not the functional disability. Compared with the 2-year follow-up a significant increase in functional disability was observed, as measured by the DRI, but not the ODI, in the surgical group at long term. In the exercise group no significant changes were observed between the 2-year and the long-term follow-up. Cross-sectional analysis: Between the surgical and conservative group no significant differences were observed in any outcome measurement at long-term follow-up except for global assessment, which was significantly better for surgical patients. Of surgical patients 76% classified the overall outcome as much better or better compared with 50% of conservatively treated patients (p=0.015). Quality of life as estimated by the SF-36 at long term was not different between treatment groups in any of the eight domains studied but was considerably lower than for the normal population. CONCLUSIONS: Posterolateral fusion in adult lumbar isthmic spondylolisthesis results ina modestly improved long-term outcome compared with a 1-year exercise program. Although the results show that some of the previously reported short-term improvement is lost at long term, patients with fusion still classify their global outcome as clearly better than conservatively treated patients. Furthermore, because the long-term outcome of the patients conservatively treated most likely reflects the natural course, one can also conclude that no considerable spontaneous improvement should be expected over time in adult patients with symptomatic isthmic spondylolisthesis. Substantial pain, functional disability and a reduced quality of life will in most patients most likely remain unaltered over many years.     

单侧椎弓根钉固定结合单枚融合器治疗腰椎不稳症

目的：探讨经椎间孔入路单侧椎弓根钉固定结合单枚融合器治疗腰椎不稳症的临床疗效。方法：回顾性分析2009年至2012年收治且获得8个月以上随访腰椎不稳症50例,均有顽固性或反复下腰痛,有单侧或单侧为主的下肢放射痛,X线片及CT片显示腰椎不稳。采用经椎间孔入路单枚融合器椎间融合,结合单侧或双侧椎弓根钉固定治疗。根据固定方法不同,分为单侧固定组和双侧固定组。单侧固定组20例22间隙,男8例,女12例;年龄26-66岁;峡部裂性Ⅰ度滑脱2例,退行性滑脱8例,腰椎间盘突出症10例;融合部位L3,41例,L4,512例,L5S19例。双侧固定组30例30间隙,男14例,女16例;年龄41-62岁;峡部裂型Ⅰ度滑脱4例,退行性滑脱14例,腰椎间盘突出症12例;融合部位L3,43例,L4,515例,L5S112例。分析两组患者的手术时间、术中出血量、术后引流量、并发症情况,并对其椎间隙高度、前凸角的变化、融合率及临床疗效等进行比较。结果：两组患者术后切口均Ⅰ期愈合,腰痛基本消失,下肢放射痛均消失,无感染、硬脊膜损伤等发生。单侧固定组术后无医源性神经症状,双侧固定组术后1例足下垂。所有患者获得随访,时间8-18个月,平均（10.8±4.3）个月。临床疗效按照JOA评分好转率（RIS）评定,两组均获得较好临床疗效,且两组融合率比较差异无统计学意义,两种内固定治疗方法均能有效增加病变椎间隙高度。单侧固定组较双侧固定组手术时间更短,术中出血和术后引流量更少。结论：只要严格掌握手术适应证,注意手术操作技巧,经椎间孔入路单枚融合器加单侧椎弓根钉治疗腰椎不稳症具有创伤小、出血少、恢复快、经济实用等优点。     

BAK椎间融合器治疗轻度腰椎峡部型滑脱症

自1997年4月～1998年4月间,以多孔螺纹状椎间融合器(BAK)行后路腰椎椎体融合术(PLIF)治疗8例轻度L_5/S_1峡部型滑脱症病人。患者主要症状为反复发作的下腰痛,伴有一侧(5例)或双侧(3例)的下肢疼痛。术前侧位X线片显示腰5椎体轻度向前滑脱(15％～30％滑移程度),且该椎间隙高度较邻近之正常间隙降低30％以上;斜位片示峡部裂隙6例(其中1例为单侧)、峡部细长2例。双侧症状者行后前向双枚BAK椎间融合器PLIF。术后平均随访12月,皆达到临床融合。所有患者均无融合器的移位,患者主观满意率100％。作者认为,BAK椎间融合器植入行后路腰椎椎体间融合术,能充分完成后路减压、保证可靠的融合,且无需应用附加内固定,不失为一种比较理想的治疗轻度腰椎峡部型滑脱手术方法。     

Combined dysplastic and isthmic spondylolisthesis: possible etiology.

STUDY DESIGN: Four cases of combined dysplastic and higher-level isthmic spondylolisthesis were studied. OBJECTIVE: To attempt to understand the possible etiology of this unreported combination. SUMMARY OF BACKGROUND DATA: Dysplastic spondylolisthesis is thought to be hereditary. It is believed that isthmic spondylolisthesis, the more common type, is acquired. Multiple spondylolysis and spondylolisthesis have been reported, but no cases of combined dysplastic and isthmic spondylolisthesis. METHODS: The global and segmental Cobb angles of the lumbar vertebrae and sagittal vertical alignment were measured in four patients who presented with lower back pain and varying degrees of pain radiation to the lower limb. Posteroanterior and lateral radiographs were taken with patients standing barefooted. Three of the patients underwent surgery. The fourth patient refused surgery. RESULTS: The global and segmental Cobb angles were found significantly increased in these patients. Increased segmental extension angles were clearer at the levels above the dysplastic vertebrae and at the level of the isthmic defect. Large anterior translation of the thorax was noted in all cases. CONCLUSIONS: The authors believe that this unusual combination may have resulted from hyperlordosis occurring above the dysplastic vertebrae, which caused increased stresses that led to the isthmic defect. This combination should be investigated in patients with dysplastic spondylolisthesis and hyperlordosis.     

Preoperative evaluation of adult isthmic spondylolisthesis with diskography

Fourteen consecutive patients with a diagnosis of isthmic spondylolisthesis (grade I and II) underwent provocative lumbar diskography (L2-S1) to evaluate the disk adjacent to the spondylolisthesis. Seven (50%) of 14 patients had concordant pain at the disk above the slip and 2 patients had no pain at the slip level. Surgical treatment included anteroposterior fusion of the slip level and any adjacent concordant levels. Clinical results included 3 excellent, 7 good, 2 fair, and 1 poor outcome. This data supports the hypothesis that the disk adjacent to an isthmic slip is predisposed to symptomatic degeneration in the adult patient with axial pain. It does not prove that a fusion is indicated or that clinical outcomes would be improved with this approach.     

High-grade L5 spondylolisthesis associated with dural ectasia in neurofibromatosis

A 15-year-old girl was admitted to our hospital with severe low back pain. She had scoliosis dextra and tight hamstrings. A plain radiograph showed high-grade L5 spondylolisthesis with vertebral scalloping from the fourth lumbar to the first sacral vertebra. L5 wide laminectomy and posterior lumbar interbody fusion by iliac bone graft was performed using the Galveston method of sacral fixation and a pedicle screw system. The rod and hook system was used from T9 to the bilateral iliac wing. We added posterolateral fusion from T10 to S1 by autograft and allograft. The patient became pain free and was able to return to student life. Three years after surgery, the radiographs demonstrated good bony fusion; however, careful long-term follow-up is needed.     

腰5椎体Ⅱ度以上峡部裂性滑脱的手术策略

目的探讨腰5椎体Ⅱ度以上峡部裂性滑脱的手术治疗策略。方法 2003年8月～2008年10月,应用经椎间孔腰椎间融合（transforaminal lumbar interbody fusion,TLIF）技术,以小关节突为中心椎管减压、椎间隙松解撑开复位、椎弓根钉棒系统补充复位固定、椎间隙打压植骨联合椎间融合器技术治疗腰5椎体Ⅱ度以上峡部裂性滑脱26例。结果经18～36个月（平均30个月）随访,滑脱椎体复位无丢失,椎间隙高度维持良好,下腰椎生理弧度恢复正常,椎弓根螺钉无断裂、松动,融合器无移位、沉降。25例获骨性融合。根据NaKai评分标准,优良率为84.6%。结论采用TLIF技术治疗腰5椎体Ⅱ度以上滑脱,神经根管减压是影响疗效的关键因素,滑脱椎体复位有利于神经根减压以及椎间融合率的提高,椎体间融合是维持长期疗效的基础。     

Instrumented and noninstrumented posterolateral fusion in adult spondylolisthesis--a prospective randomized study: part 2

STUDY DESIGN: A prospective randomized study was performed. OBJECTIVE: To determine whether transpedicular fixation improves the outcome of posterolateral fusion in patients with adult isthmic spondylolisthesis. SUMMARY OF BACKGROUND DATA: The use of transpedicular fixation remains controversial. Both a positive effect and no effect from additional transpedicular fixation have been reported. METHODS: In this study, 77 patients randomly underwent posterolateral fusion with (n = 37) or without (n = 40) transpedicular fixation. The inclusion criteria were lumbar isthmic spondylolisthesis of any grade, at least 1 year of low back pain or sciatica, and severely restricted functional ability in individuals 18 to 55 years of age. RESULTS: The follow-up rate was 94%. At a 2-year follow-up assessment, the level of pain and functional disability were strikingly similar in the two groups, and there was no significant difference in fusion rate. CONCLUSIONS: Lumbar posterolateral fusion performed in situ for adult isthmic spondylolisthesis relieves pain and improves function. The use of supplementary transpedicular instrumentation does not add to the fusion rate or improve the clinical outcome.     

Vertebral osteolysis after posterior interbody lumbar fusion with recombinant human bone morphogenetic protein 2: a report of five cases.

BACKGROUND: Recombinant human bone morphogenetic protein 2 (rh-BMP-2) is frequently used in an off-label fashion. Its application for posterior interbody fusion appears intuitive because its use obviates the need for iliac crest bone graft and shows higher fusion rates than with the use of local autologous bone graft. To date, there is no report of adverse outcomes with such use of rh-BMP-2. PURPOSE: To draw attention to this unusual complication of posterior interbody lumbar fusion and to review the relevant literature. STUDY DESIGN: Clinical report of five cases of vertebral osteolysis that developed postoperatively from lumbar transforaminal interbody fusion of the L5/S1 motion segment using cages and rh-BMP-2. METHODS: Sixty-eight patients underwent transforaminal lumbar interbody fusion for spondylolisthesis or degenerative disc disease with discogenic back pain. Five of these 68 patients developed vertebral osteolysis within 4 months from their surgery. Their clinical presentation and radiographic findings are presented in this case series. RESULTS: Each one of these five patients had uneventful surgery and postoperative recovery. Their back and leg pain improved in the immediate postoperative period. However, each patient reported worsening back pain with variable radicular pain as early as 4 weeks and as late as 3 months after the index procedure. Diagnostic workup revealed evidence of vertebral osteolysis typically involving the L5 vertebral body. In all five patients, osteolytic defects filled in spontaneously, and symptoms typically resolved within an additional 3 months of nonoperative care. CONCLUSIONS: Vertebral osteolysis can occur with the use of rh-BMP-2 in posterior lumbar interbody fusions. Violation of the end plate during decortication may be a contributing factor. Symptoms often resolve spontaneously.     

Comparison of Functional Outcomes following Surgical Decompression and Posterolateral Instrumented Fusion in Single Level Low Grade Lumbar Degenerative versus Isthmic Spondylolisthesis

Background

The two most common types of surgically treated lumbar spondylolisthesis in adults include the degenerative and isthmic types. The aim of this study was to compare the functional outcomes of surgical decompression and posterolateral instrumented fusion in patients with lumbar degenerative and isthmic spondylolisthesis.

Methods

In this retrospective study, we reviewed the clinical outcomes in surgically treated patients with single level, low grade lumbar degenerative, and isthmic spondylolisthesis (groups A and B, respectively) from August 2007 to April 2011. We tried to compare paired settings with similar initial conditions. Group A included 52 patients with a mean age of 49.2 ± 6.1 years, and group B included 52 patients with a mean age of 47.3 ± 7.4 years. Minimum follow-up was 24 months. The surgical procedure comprised neural decompression and posterolateral instrumented fusion. Pain and disability were assessed by a visual analog scale (VAS) and the Oswestry Disability Index (ODI), respectively. The Wilcoxon and Mann-Whitney U-tests were used to compare indices.

Results

The most common sites for degenerative and isthmic spondylolisthesis were at the L4-L5 (88.5%) and L5-S1 (84.6%) levels, respectively. Surgery in both groups significantly improved VAS and ODI scores. The efficacy of surgery based on subjective satisfaction rate and pain and disability improvement was similar in the degenerative and isthmic groups. Notable complications were also comparable in both groups.

Conclusions

Neural decompression and posterolateral instrumented fusion significantly improved pain and disability in patients with degenerative and isthmic spondylolisthesis. The efficacy of surgery for overall subjective satisfaction rate and pain and disability improvement was similar in both groups.     

Effect of major axial skeleton trauma on preexisting lumbosacral spondylolisthesis.

The incidental occurrence of lumbar spine fractures in individuals with preexisting first degree lumbosacral isthmic spondylolisthesis may be looked upon as a simulated in vivo biomechanical experiment testing the stability of the lumbosacral subluxation. Among 200 patients with thoracolumbar spine fractures managed at the author's institution during the period of 1980-1989, five such cases were collected. All patients had a grade I isthmic spondylolisthesis at the L5-S1 level, and all sustained a burst fracture of the lumbar spine. In two patients, there was a previous history of low back pain and lumbosacral spondylolisthesis. In the other three patients, the olisthesis was judged to be old by a negative 99mTc-MDP bone scan, whereas the fractured vertebra showed intense uptake and/or by the negative operative findings at L5-S1 level during surgery. It was found that the incidence of lumbosacral spondylolisthesis in patients with thoracolumbar fractures was smaller than in the general population but the difference was not statistically significant (p = 0.213). In addition, it is concluded that mild lumbosacral spondylolisthesis can absorb considerable axial loading without an ascertainable evidence of damage.     

Reduction of high-grade isthmic and dysplastic spondylolisthesis in 5 adolescents

Treatment of high-grade isthmic and dysplastic spondylolisthesis in children and adolescents remains a challenge. Surgical treatment of spondylolisthesis has been recommended in adolescents with pain refractory to nonoperative modalities, slippage progression, or > 50% slippage on presentation. Controversy exists as to the optimal surgical approach for high-grade spondylolisthesis. In this report, we describe 5 cases of high-grade isthmic and dysplastic spondylolisthesis in adolescents and review the literature on surgical treatment for this entity. Operative records, charts, x-rays, and Scoliosis Research Society outcome questionnaires (SRS-22) were retrospectively evaluated for 5 consecutive patients diagnosed with and treated for high-grade spondylolisthesis. Each patient received treatment consisting of decompression, reduction, and circumferential fusion with transpedicular and segmental fixation from a posterior approach. Two patients had transient L5 nerve root deficit, which resolved within 3 months. Reduction benefits include a decrease in shear stresses (and resulting decreased rates of postoperative pseudarthrosis and slip progression), restoration of sagittal alignment and lumbosacral spine balance, and improvement in clinical deformity.     

Progression of lumbosacral isthmic spondylolisthesis in adults

STUDY DESIGN: A retrospective clinical and radiographic review of adult patients with progressive isthmic lumbosacral spondylolisthesis. OBJECTIVES: To describe the clinical presentation of adult-onset progression of isthmic spondylolisthesis and to analyze its causes. SUMMARY OF BACKGROUND DATA: Until recently, progression of lumbosacral spondylolisthesis in adults was rarely reported. On the contrary, although slip progression before skeletal maturity has been widely recorded, its occurrence in adults has been doubted. Only sporadic case reports of adult slip progression and only brief notes on the subject in clinical studies describing other aspects of spondylolisthesis have been published. METHODS: Patients with isthmic lumbosacral spondylolisthesis who had serial radiographs of the lumbar spine on which slip progression during adult life was noted were evaluated. The amount of vertebral slip was calculated in millimeters from decubitus lateral spinal radiographs. The calculation was expressed as the percentage of slipped vertebral body length. RESULTS: From 1989 to 1995, 18 patients (9 women and 9 men), ages 32 to 55 years, with documented adult isthmic slip progression were identified at the Spinal Surgery Unit of the Hadassah University Hospital. All patients reported incapacitating low back pain, accompanied in most by significant sciatica. Documented slip progression ranged from 9% to 30% (average, 14.6%), and occurred during a period of 2 to 20 years (average duration, 6.8 years). Slip progression started after the third decade of life and coincided with marked disc degeneration at the olisthetic level. Slip progression associated with disc degeneration (i.e., intervertebral space narrowing and the formation of spondylophytes and vacuum phenomenon) brought about severe clinical symptomatology related to segmental instability and spinal stenosis. Of the 18 patients in this study, 14 were treated with surgery. All these patients except 1 underwent decompression, pedicle screw fixation, and bilateral lateral fusion. One patient underwent posterolateral fusion without instrumentation. Immediate postoperative complications were observed in three patients, including two superficial wound infections and one transient foot drop. Solid fusion was obtained in 11 of the 14 patients who underwent surgery. CONCLUSIONS: The concurrent occurrence of disc degeneration at the slip level and adult slip progression explains how an asymptomatic developmental lesion, present for at least two to three decades, may become symptomatic.     

Pedicle fracture after instrumented posterolateral lumbar fusion: a case report

STUDY DESIGN: The case report of a 60-year-old man with late onset back pain after lumbar spine fusion is presented. OBJECTIVE: To report the rare complication of bilateral pedicle stress fractures after instrumented posterolateral lumbar fusion. SUMMARY OF BACKGROUND DATA: A 56-year-old man underwent revision spinal surgery for ongoing back pain secondary to pseudoarthroses. A posterolateral L4-S1 instrumented fusion using pedicle screws was performed. Autologous bone graft was applied to the decorticated lateral masses. The internal fixation was removed 2 years later, at which time plain radiographs showed that the fusion mass was solid. At the age of 60 years, the man presented with worsening back pain. Plain radiographs and computed tomographic scans demonstrated bilateral L4 pedicle stress fractures. A bone scan indicated that these were recent in origin. METHOD: The clinical assessment was undertaken by the senior author and surgeon. Investigations included plain radiography, computer tomography, and scintographic imaging. A systematic literature review of the relevant publications was performed. RESULTS: In the reported patient, bilateral pedicle stress fractures developed 2 years after pedicle screw removal from an L4-S1 instrumented posterolateral lumbar spine fusion. This occurred at the uppermost level of the fusion mass. CONCLUSIONS: The pedicle is the weakest point in the neural arch after posterolateral fusion. Although movement continues at the level of the disc space anteriorly, the pedicle is susceptible to fracture. Pedicle fracture is a rare late complication of posterolateral lumbar spine fusion.     

腰椎管狭窄症伴不稳定性腰椎退变性滑脱的手术治疗

目的　探讨腰椎管狭窄伴不稳定性腰椎退变性滑脱的手术治疗疗效。　方法　回顾性分析 86例腰椎管狭窄伴不稳定性腰椎退变滑脱的手术治疗结果 ,其中男 30例 ,女 5 6例 ,年龄 30～ 77岁 ,平均 5 5 8岁 ,腰痛合并双侧下肢痛 6 3例 ,单侧下肢痛 10例 ;单纯腰痛 13例 ,其中 72例主诉间歇性跛行 ,出现跛行的行走距离 10～ 10 0 0m ,32例合并有足部感觉、运动及反射的改变。本组病例均并存病变节段的腰椎动力性腰椎不稳 ,滑脱Ⅰ° 79例 ,Ⅱ° 7例。术前CT检查 5 6例 ,MRI检查 2 4例 ,MRM检查 6例 ,术前同时行脊髓造影 6 1例 ,CTM检查 12例。狭窄并滑脱的节段 :L4 549例 ,L3 46例 ,L5 S12 5例 ,L3 4、L4 52例 ,L3 S14例。单纯侧隐窝狭窄 10例 ,双侧侧隐窝狭窄 2 2例 ,中央椎管狭窄 5 4例 ;合并椎间盘突出 12例。所有的患者均经手术减压、植骨融合及不同的内固定治疗。　结果　患者均经 8个月～ 13年的随访 ,其中随访 1年以上者 81例 (平均 5 6年 )。本组优 78例 ,良 5例 ,可 3例。滑脱完全复位Ⅰ° 70例 (89 9% ) ,Ⅱ° 6例 (85 7% )。随访过程中无滑脱加重患者 ,3个月内植骨融合者 74例 ,6个月内植骨融合 10例 ,出现假关节 2例。术后发生内固定断裂 1例 ,晚发感染 1例。结论　减压和脊柱固定可改善腰椎管     

Anterior spondylodesis for spondylolisthesis: Isthmic and degenerative types

Summary We studied the influence of instability of the spondylolisthesic segment upon anterior interbody fusion (AIF) rates. A one-level AIF of the lumbar spine by the modified extraperitoneal Bailey-Badgley fusion construct was performed in 26 patients with chronic or recurring acute low-back pain and/or other symptoms due to grades I and II spondylolisthesis. Sixteen were degenerative type, and 10 were isthmic type. Seventeen were female and 9, male. The average age was 41.2 years. The number of cases of spondylolisthesis at the level of L4–5 and L5-S1 as 18 and 8, respectively. In the 16 cases of degenerative type, 13 were grade I slip, and 3 were grade II slip, while in the 10 cases of isthmic type, 8 were grade I slip, and 2 were grade II slip. The average postoperative follow-up was 6 years (range 2–10 years). Solid fusion was obtained in 15 (93.8%) of the cases of degenerative spondylolisthesis and in 6 of the cases of isthmic type. Thus, the overall fusion rate was 80.7% (21 cases). However, some graft crumbling and redisplacement developed in 1 of the cases of degenerative type and 6 of the cases of isthmic type. Non-union developed in 4 (57.1%) of those 7 cases of graft crumbling (3 isthmic and 1 degenerative type). Fusion took 7 months on average (range 5–9 months). It is hypothesised that the isthmic-type spondylolisthesis has more instability than the degenerative one. Therefore, AIF in the case of degenerative spondylolisthesis is a useful procedure, while in the isthmic type it is not advisable as a routine procedure.     

High failure rate of the interspinous distraction device (X-Stop) for the treatment of lumbar spinal stenosis caused by degenerative spondylolisthesis

The X-Stop interspinous distraction device has shown to be an attractive alternative to conventional surgical procedures in the treatment of symptomatic degenerative lumbar spinal stenosis. However, the effectiveness of the X-Stop in symptomatic degenerative lumbar spinal stenosis caused by degenerative spondylolisthesis is not known. A cohort of 12 consecutive patients with symptomatic lumbar spinal stenosis caused by degenerative spondylolisthesis were treated with the X-Stop interspinous distraction device. All patients had low back pain, neurogenic claudication and radiculopathy. Pre-operative radiographs revealed an average slip of 19.6%. MRI of the lumbosacral spine showed a severe stenosis. In ten patients, the X-Stop was placed at the L4–5 level, whereas two patients were treated at both, L3–4 and L4–5 level. The mean follow-up was 30.3 months. In eight patients a complete relief of symptoms was observed post-operatively, whereas the remaining 4 patients experienced no relief of symptoms. Recurrence of pain, neurogenic claudication, and worsening of neurological symptoms was observed in three patients within 24 months. Post-operative radiographs and MRI did not show any changes in the percentage of slip or spinal dimensions. Finally, secondary surgical treatment by decompression with posterolateral fusion was performed in seven patients (58%) within 24 months. In conclusion, the X-Stop interspinous distraction device showed an extremely high failure rate, defined as surgical re-intervention, after short term follow-up in patients with spinal stenosis caused by degenerative spondylolisthesis. We do not recommend the X-Stop for the treatment of spinal stenosis complicating degenerative spondylolisthesis.     

Transforaminal lumbar interbody fusion: technique, complications, and early results

OBJECTIVE: To demonstrate the safety, surgical efficacy, and advantages of the transforaminal approach for lumbar interbody fusion when combined with pedicle screw fixation. METHODS: We retrospectively reviewed the records of 22 patients (age range, 34-63 yr; mean, 49 yr) with Grade I or II spondylolisthesis who underwent transforaminal lumbar interbody fusion. Nineteen patients presented with low back pain and associated radiculopathy, and three presented with low back pain only. Transforaminal lumbar interbody fusion was performed at L4-L5 in 8 patients, L5-S1 in 11 patients, L3-L4 and L4-L5 in 2 patients, and L4-L5 and L5-S1 in 1 patient. Periodic follow-up took place 1 to 12 months after surgery (mean, 5.3 mo). Decompression is performed according to clinical circumstances. Pedicle screws are placed, and a discectomy is carried out. The cartilaginous endplates are removed. The interspace is gradually distracted, resulting in lost disc height being regained, and interbody fusion cages are positioned. The pedicle screw-and-rod construct is then compressed, restoring lumbar lordosis. RESULTS: Low back pain completely resolved in 16 patients, moderate relief from pain was achieved in 5 patients, and the pain was unchanged in one patient. Nonneurological complications included intraoperative durotomy in one patient and postoperative wound infection in two. In one patient, postoperative mild L5 motor paresis resolved. One patient had a temporary brachial plexopathy due to intraoperative positioning, and one patient had peripheral polyneuropathy secondary to prolonged intraoperative blood pressure cuff inflation. CONCLUSION: Transforaminal lumbar interbody fusion is a safe and effective method for achieving circumferential spinal fusion via a single-stage procedure. This procedure is particularly useful in restoring disc space height and lumbar lordosis.     

单枚融合器附加椎弓根螺钉系统在腰椎滑脱治疗中的应用

目的探索以单枚椎间融合器后斜向植入附加椎弓根螺钉系统内固定的后路腰椎椎体间融合术治疗腰椎滑脱症.方法1997年7月～2000年8月,我们收治了各类腰椎滑脱症65例患者(男32例,女33例.年龄28～58岁,平均43岁).其中,峡部型滑脱症(Ⅰ～Ⅱ°)26例,退行性滑脱症25例,腰椎后路减压术后滑脱症7例,发育不良性腰椎滑脱症5例,外伤性滑脱症2例.均有一年以上的下腰痛和/或下肢根性症状且保守治疗无效.所有患者均在减压的基础上行病变节段的单枚螺纹式椎间融合器(BAK)的后斜向植入并附加用椎弓根螺钉系统内固定.结果65例中有59例平均随访达18月,皆达到临床融合.临床效果评价优42例,良14例,无改善3例,差0例.患者主观评定满意41例,基本满意15例,可3例所有患者均无融合器的移位及椎弓根螺钉松动,患者主观满意率93%.结论经侧后方斜向植入单枚螺纹状椎间融合器并附加椎弓根螺钉内固定的后路腰椎椎体间融合术式能充分完成后路减压,并能保证可靠的融合,适用于滑脱程度严重、滑脱倾向大的患者,不失为一种比较理想的治疗各种腰椎滑脱症的术式.