Clinical outcome of microendoscopic posterior decompression for spinal stenosis associated with degenerative spondylolisthesis--minimum 2-year outcome of 37 patients

A clear consensus for the optimal surgical treatment for spinal stenosis associated with degenerative spondylolisthesis (DS) has not appeared. In general, decompression and fusion are recommended. However, the symptoms of spinal stenosis are the main complaints in almost all patients with DS, and whether or not routine concomitant fusion is necessary in the surgical treatment for DS is still discussed controversially. The authors have treated almost all the patients with spinal stenosis associated with DS by microendoscopic posterior decompression (MEPD) procedures since 2001. In the present study, we examined the minimum 2-year outcome in 37 patients surgically treated with the MEPD procedures for spinal stenosis associated with DS. At the mean of 38 months after surgery, the overall results were excellent in 54% of the patients, good in 19%, fair in 13.5%, and poor in 13.5%, based on the Japanese Orthopedic Association lumbar score, a visual analogue scale, and the Roland-Morris disability questionnaire. Although the progression of spondylolisthesis and the increase of segmental sagittal motion after surgery were seen in 7 patients (19%), only one patient required secondary fusion during the follow-up period. A sufficient decompression with the preservation of the posterior structures of the spine was observed in almost the patients after surgery. In conclusion, the MEPD is a minimally invasive procedure developing a sufficient decompression with the preservation of the spinal stability. Thus, the MEPD is one of the useful procedures in the surgical treatment of spinal stenosis associated with DS. However, further follow-up studies should be performed to evaluate the long-term outcome for evaluation of the true validity of the MEPD for DS.     

A clinical study of degenerative spondylolisthesis. Radiographic analysis and choice of treatment.

Surgical treatment of degenerative spondylolisthesis in 27 patients by means of anterior lumbar interbody fusion and in 14 patients by means of posterior decompression yielded average degrees of recovery of 77% and 56%, respectively. Preoperative analysis of myelograms, and computed tomographies after myelography indicated that anterior shifting of the inferior articular process of the slipping vertebra was the main factor responsible for compression of the nervous tissue in the early stages of degenerative spondylolisthesis. Patients in these stages should be treated by anterior lumbar interbody fusion. In the later stages of degenerative spondylolisthesis, osteophytes on the superior articular processes of the lower vertebra were an additional factor in compression, and patients should be treated by posterior decompression. Computed tomographies after myelography provided the key images for identifying pathologic processes in degenerative spondylolisthesis and selecting appropriate surgical procedures.     

Degenerative spondylolisthesis of the cervical spine: analysis of 58 patients treated with anterior cervical decompression and fusion

Background contextDegenerative spondylolisthesis has been well described as a disorder of the lumbar spine. Few authors have suggested that a similar disorder occurs in the cervical spine. To our knowledge, the present study represents the largest series of patients with long-term follow-up who were managed surgically for the treatment of degenerative spondylolisthesis of the cervical spine.PurposeTo describe the clinical presentation and radiographic findings associated with degenerative cervical spondylolisthesis, and to report the long-term results of surgically managed patients.Study designAnalysis of 58 patients treated with anterior cervical decompression and fusion for degenerative spondylolisthesis of the cervical spine.Patient sampleFrom 1974 to 2003, 58 patients were identified as having degenerative spondylolisthesis of the cervical spine occurring in the absence of trauma, systemic inflammatory arthropathy, or congenital abnormality. These patients were identified from a database of approximately 500 patients with degenerative cervical spine disorders treated by the senior one of us.Outcome measuresPatient outcomes were evaluated with regard to neurologic improvement (Nurick grade myelopathy) and osseous fusion.MethodsThe records of 58 patients were reviewed. The average follow-up period was 6.9 years (range, 2–24 years). Seventy-two cervical levels demonstrated spondylolisthesis. In all cases, there was radiographic evidence of facet degeneration and subluxation. All patients were treated with anterior cervical decompression and arthrodesis with iliac crest structural graft. This most commonly involved corpectomy of the caudal vertebrae. Three patients required additional posterior facet fusion.ResultsFifty-eight patients demonstrated 72 levels of involvement. The C4–C5 level was most frequently involved (43%). Two radiographically distinct types of listhesis were observed based on the amount of disc degeneration and the degree of spondylosis at adjacent levels. The average neurologic improvement was 1.5 Nurick grades. The overall fusion rate was 92%. Three patients were treated with combined anterior-posterior arthrodesis. The prevalence of myelopathy and instability pattern was greater in the listheses occurring adjacent to spondylotic levels.ConclusionsDegenerative spondylolisthesis is relatively common in the cervical spine. Common to all cases is facet arthropathy and neurologic compression. Anterior cervical decompression and arthrodesis appears to yield excellent union rates and neurological improvement in those patients having cervical degenerative spondylolisthesis and significant neurological sequelae who have failed nonoperative treatments.     

退变性腰椎滑脱症的手术治疗

目的探讨采用后路腰椎椎管减压、钉棒内固定并椎间植骨融合术和后路腰椎减压并Dynesys系统内固定手术治疗退变性腰椎滑脱的效果。方法应用后路腰椎椎间融合（posterior lumbar interbody fusion,PLIF）术进行椎管减压、钉棒系统固定并椎体间植骨融合手术治疗退变性腰椎滑脱37例;应用后路腰椎管减压并Dynesys内固定手术治疗退变性腰椎滑脱5例。结果随访9～39个月,平均26个月,腰痛疼痛视觉模拟量表（visual analogue scale,VAS）评分术前为8.7分,随访时为2.1分;腿痛VAS评分术前为7.6分,随访时为2.3分。术前Oswestry功能障碍指数（Oswestry disability index,ODI）为58.2%,随访时为21.2%。无严重手术并发症发生。术后X线片复查显示椎间高度均得到不同程度的恢复,滑脱椎体完全复位或者基本复位,椎间植骨融合。无融合器移位或螺钉松动、断裂。结论后路腰椎椎管减压、钉棒内固定并椎间植骨融合术和后路腰椎减压并Dynesys内固定手术治疗退变性腰椎滑脱效果满意,安全彻底的神经根管减压是取得满意临床效果的关键。     

退行性腰椎滑脱后路手术临床分析

目的 探讨退行性腰椎滑脱的后路手术治疗,比较后路腰椎管减压内固定并后外侧植骨及椎体间联合后外侧植骨术的临床疗效.方法 37例退行性腰椎滑脱患者采用后路减压、后外侧植骨内固定(A组21例)和椎体间联合后外侧植骨内固定(B组16例)手术,对两组术后植骨融合率及临床症状改善情况进行分析比较.根据术前、术后X线片和JOA评分评价植骨融合率及临床症状改善程度.结果 平均随访42个月.A组骨融合率为86%,B组为94%,两组无显著性差异.A组JOA评分优良率为90%,B组为94%,两组无显著性差异.结论 后路后外侧植骨内固定和椎间联合后外侧植骨内固定术均是有效的手术方法,但椎间联合后外侧植骨融合术的骨融合率较高.     

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.     

腰椎退变性滑脱合并椎间盘突出的诊断及手术治疗分析

目的探讨腰椎退变性滑脱合并椎间盘突出的影像学、临床特点及手术治疗效果。方法回顾分析89例腰椎退变性滑脱合并椎间盘突出患者的临床症状、体征及影像学检查,进行合理的手术评估,行后路次全椎板切除椎管减压、椎间盘髓核摘除、椎间隙植骨融合、椎弓根钉棒系统内固定术。结果手术治疗后优73例,良10例,可6例,优良率93.3%。术后随访1～3年,滑脱椎体复位,椎弓根钉棒系统内固定在位有效,无松动,临床症状基本消失。植骨融合率第一年为90.8%,第二年全部骨性融合。结论采用后路次全椎板切除椎管减压、椎间盘髓核摘除、椎间隙植骨融合、椎弓根钉棒系统内固定术,在处理腰椎间盘突出的同时纠正了腰椎滑脱,达到了脊柱稳定、解除症状的目的。     

Spinal stenosis in grade I degenerative lumbar spondylolisthesis: a comparative study of outcomes following laminoplasty and laminectomy with instrumented spinal fusion

The management of grade I lumbar degenerative spondylolisthesis remains controversial. There have been few reports comparing any form of surgery with conservative treatment. As for surgical management, the need for arthrodesis with instrumentation has not been established. A series of 53 patients with single-level spinal stenosis at L4/5 due to grade I degenerative spondylolisthesis entered into a study to compare outcomes of two surgical methods of treatment with those of a control group treated conservatively: group 1, 19 patients treated by decompression laminectomy combined with posterolateral fusion and pedicle screw instrumentation; group 2, 18 patients treated by decompression of the spinal canal using a laminoplasty technique to preserve the integrity of the midline structure; group 3, 16 patients treated conservatively after being recommended that they have surgery. We compared the 2-year results among the three groups. Alleviation of symptoms was noted in groups 1 and 2, whereas the controls (group 3) showed no improvement. There was no significant difference in the degree of clinical improvement between groups 1 and 2. Spondylolisthesis was controlled in group 1, but it did not lead to better clinical results than those achieved in group 2. Our findings indicate that the technique for decompressing the spinal canal with preservation of the posterior elements of its roof can be useful for treating patients with grade I degenerative spondylolisthesis with symptoms of spinal stenosis.     

腰椎滑脱合并椎管狭窄的手术治疗

目的：分析比较不同手术和植骨融合方式对腰椎滑脱合并椎管狭窄的治疗效果。方法：对76例诊断为腰椎滑脱合并椎管狭窄进行彻底的椎管减压，采用三种方法内固定，U型棒23例，Steffee钢板20例，RF系统33例；二种方法植骨融合；两侧横突及关节突间植骨融合50例，后路椎体间Cage植骨26例。结果：随访6个月－10年，患临床症状缓解优良率为92．1％，对滑椎的复位率Steffee钢板和RF系统分别是90．0％和81．8％，U型棒则几乎起不到复位作用，二种椎间植骨融合率分别为94．0％和96．2％，结论：腰椎滑脱合并椎管狭窄手术治疗时应彻底椎管减压，椎弓根螺钉系统能可靠地将滑椎复位，复位后应根据病人的具体情况选择适当的椎体间植骨融合。     

Patient outcomes after minimally destabilizing lumbar stenosis decompression: the "Port-Hole" technique

STUDY DESIGN: A prospective evaluation of the outcome of a decompressive procedure for lumbar spinal stenosis designed to preserve spinal stability. OBJECTIVES: To determine whether decompression could be achieved without subsequent fusion for spinal stenosis with and without degenerative spondylolisthesis. SUMMARY OF BACKGROUND DATA: The traditional surgical decompression of spinal stenosis involves removal of the posterior elements. Success occurs in 64% of cases, on the average, with results deteriorating over time. Concomitant spinal fusion is associated with higher costs and complication rates. METHODS: This prospective study included 54 consecutive patients treated surgically by one surgeon. Patients were contacted 21/2 and 4 years, on the average, after surgery. Patients with spondylolisthesis were evaluated for worsening of the listhesis after surgery. RESULTS: At a mean of 4 years after surgery, all patients were satisfied with their treatment. Concerning their symptoms, 80% reported relief of back pain; 96% had improvement of leg pain; 93% experienced relief of leg numbness; and 97% had relief of lower extremity weakness. Before surgery, only 1 patient could walk for longer than 15 minutes. After surgery, 98% (47/48) could walk for more than 15 minutes. Overall clinical results were graded as good to excellent (88%), fair (8%), or poor (4%). Clinical outcomes were comparable between those with and without degenerative spondylolisthesis (P = 0.08). Patients with degenerative spondylolisthesis showed no change in the amount of slip in 13/15 patients (87%). CONCLUSIONS: Degenerative spinal stenosis, even with nonlytic spondylolisthesis, can be decompressed effectively without violating the integrity of the posterior elements.     

两种手术方式治疗退变性腰椎滑脱症的疗效比较

[目的]对比椎弓根钉内固定联合单枚Cage斜形放置椎间植骨融合与椎弓根钉内固定后外侧融合治疗退变性腰椎滑脱的临床疗效。[方法]单节段退变性腰椎滑脱患者44例,按手术方式分为:Ⅰ组23例,行椎弓根器械复位固定后单枚Cage斜形放置的椎体间融合;Ⅱ组21例,行椎弓根器械复位固定后外侧融合。对两组术后JOA评分,腰腿痛VAS评分,影像学进行随访。[结果]随访15~36个月,两组间JOA评分、骨融合率无显著性差异(P>0.05);Ⅰ组在下腰痛缓解的VAS评分、Taillard指数、相对椎间隙高度的维持方面优于Ⅱ组(P<0.05)。[结论]单枚融合器附加椎弓根钉的椎间植骨融合是治疗退变性腰椎滑脱更为理想的方法。     

退变性腰椎管狭窄症的手术治疗

目的探讨退变性腰椎管狭窄症（degenerative lumbar spinal stenosis,DLSS）手术治疗方法。方法回顾性分析2003年1月至2011年1月我院185例退变性腰椎管狭窄症手术治疗病例。其中神经根管狭窄6例,中央管狭窄179例。单节段狭窄者96例,双节段狭窄者55例,3个节段狭窄者34例。采用单纯开窗减压者6例,后路全椎板切除减压、后外侧植骨融合、内固定70例,后路全椎板切除减压、椎体间植骨融合、内固定109例。根据日本矫形外科学会腰腿痛评分系统（15分）进行术前和术后的疗效评价。结果 185例患者获得8～72个月随访,平均随访时间19.5个月。三种手术方法术后平均改善率分别为77.9%、78.8%和79.5%,优45例,良120例,可20例,优良率为89.2%。术后并发脑脊液漏6例。结论根据DLSS患者病情和影像学检查结果,确定狭窄的部位和节段,对神经根管狭窄者,采用单纯开窗减压;对中央管狭窄者,采用全椎板切除减压、椎体间植骨融合和/或后外侧植骨融合、椎弓根系统内固定,尤其是对于合并腰椎节段性不稳定、退变性滑脱、侧弯和后凸者,可获得满意的疗效。     

Telamon融合技术在下腰椎不稳治疗中的作用

目的回顾性分析了Telamon融合技术在治疗下腰椎不稳定方面的作用。方法本组共68例,均为单节段病变,平均年龄49岁,腰椎椎弓崩裂伴滑脱者27例,腰椎退变性不稳者41例,术前病程平均28．6月,Oswestry残疾指数平均48．5%。所有病例均行后路减压、椎弓根螺钉内固定及Telamon椎体间融合术,其中全椎板切除者5例,双侧椎板间扩大开窗者63例。结果术后随访平均11．8个月,最后随访时Oswestry残疾指数平均7．5％,复查X线片均获良好的骨性融合,无明显不稳定征象。结论Telamon融合技术能提供良好的骨性融合并维持良好的椎体间高度和腰椎的生理性前凸,由于其本身并不具有即刻稳定性,故应在坚强内固定的保护下应用,获得良好效果的关键在于正确的手术适应证。     

Minimally invasive anterior lumbar interbody fusion followed by percutaneous pedicle screw fixation for isthmic spondylolisthesis.

BACKGROUND CONTEXT: Most surgeons have thought that posterior decompression is necessary to treat isthmic spondylolisthesis with leg pain. However, the surgical procedure not only requires wide muscle dissection but can also lead to spinal instability. The authors' treatment concept for isthmic spondylolisthesis is one-stage anterior reduction and posterior stabilization with minimally invasive surgical procedure without touching the spinal thecal sac and nerve. PURPOSE: To investigate a new surgical concept of minimally invasive anterior-posterior fusion without posterior decompression for the treatment of isthmic spondylolisthesis with leg pain. STUDY DESIGN: This is a retrospective study of 73 patients with isthmic spondylolisthesis who underwent minimally invasive anterior lumbar interbody fusion (mini-ALIF) followed by percutaneous pedicle screw fixation (PF) between October 2000 and February 2002. PATIENT SAMPLE: A total of 73 patients with low-grade isthmic spondylolisthesis (46 with Grade 1 and 27 with Grade 2) who underwent mini-ALIF followed by percutaneous PF were retrospectively analyzed. There were 20 men and 53 women, with a mean age of 50.6 (range, 19 to 77) years. All patients had low back pain and referred or radicular leg pain or neurogenic intermittent claudication in walking or standing. Average duration of symptoms was 26 (range, 3 to 120) months. OUTCOME MEASURES: The clinical outcome was graded according to the modified Macnab criteria. METHODS: The authors retrospectively reviewed clinical and radiological data of 73 patients who had isthmic spondylolisthesis. All patients underwent mini-ALIF and percutaneous PF on the same day between October 2000 and February 2002. The mean follow-up period was 16 months (range, 12 to 26). RESULTS: The mean operating time, blood loss and hospital stay were 210 minutes, 135 ml and 4.1 days, respectively. No blood transfusion was necessary. Clinical outcome was excellent in 26 patients (35.6%), good in 43 (58.9%), fair in 3 (4.1%) and poor in 1 (1.4%). The fusion rate was 97.3% (71 of 73). There were 6 cases (8.2%) of mini-ALIF complications and 6 (8.2%) of percutaneous PF complications. There were no postoperative neurologic deficits. CONCLUSIONS: Mini-ALIF followed by percutaneous PF is an efficacious alternative for low-grade isthmic spondylolisthesis, and posterior decompression is not necessary to relieve leg symptoms. This minimally invasive combined procedure offers many advantages, such as preservation of posterior arch, no nerve retraction, less blood loss, excellent cosmetic results, high fusion rate and early discharge.     

Unilateral transforaminal posterior lumbar interbody fusion (TLIF): indications, technique, and 2-year results

A prospective analysis of consecutive cases of lumbar fusion using the unilateral transforaminal posterior lumbar interbody fusion (TLIF) technique with pedicle screw fixation. The objective of the study was to assess the clinical and radiographic outcome of TLIF and describe the technique and indications in the treatment of degenerative disease of the lumbar spine. Forty patients treated with TLIF for degenerative diseases of the lumbar spine were followed up for a minimum of 2.5 years (mean: 36 months; range: 30-42 months). Twenty-three patients had degenerative disc disease alone, 13 had associated isthmic or degenerative spondylolisthesis, and 4 had recurrent disc herniations at the L4-L5 level. Thirty-six (90%) had solid fusions radiographically at latest follow-up. Seventy-nine percent had excellent or good clinical outcomes. Our patients demonstrated high fusion rates and patient satisfaction.     

腰椎退行性多节段滑脱的手术治疗

目的 探讨腰椎退行性多节段滑脱的手术治疗方法.方法 2005年3月至2008年9 月,采用后路彻底减压、复位、椎弓根内螺钉固定360°融合治疗多节段腰椎滑脱患者25例.其中男性7例,女性18例;年龄38-75岁,平均56.6岁.滑脱均为退行性变化引起,类型有:前滑脱12例,后滑脱2例,混合滑脱11例.患者均行腰椎后路减压融合手术,术后随访6个月-4年,根据 Lenke 标准评价脊柱植骨融合情况,根据 Henderson 标准评价临床疗效.结果 术后25例患者均获得完全 复位.植骨融合结果:Lenke A级23例,B级2例;临床疗效Henderson评价结果:优16例,良6例,可 3例.结论 多节段腰椎退变滑脱发病机制和治疗方法与单节段腰椎滑脱不尽相同,后路彻底减压, 适度复位,后外侧植骨融合结合椎间融合能获得较好的临床效果.多节段滑脱复位时应根据滑脱的类型选择不同方法.     

Radiographic evaluation of posterolateral lumbar fusion for degenerative spondylolisthesis: long-term follow-up of more than 10 years vs. midterm follow-up of 2–5 years

Although posterolateral fusion of the lumbar spine without instrumentation has been widely performed for spinal instability caused by degenerative spondylolisthesis in the lumbar spine, few long-term follow-up studies have been reported. We studied ten patients who underwent posterolateral fusion for degenerative spondylolisthesis in the lumbar spine without instrumentation in our hospital, five of whom were followed up for more than 10 years and the other five for 2–5 years. We used radiography to examine their fusion status, instability and degenerative changes at the fusion level, change in the slip, change in lumbar lordosis, and instability and degenerative changes one level above and one level below the fusion. In most of the ten patients, radiographic evaluation demonstrated solid fusion, minimal degenerative changes, and preservation of lumbar lordosis and spinal mobility. Posterolateral lumbar fusion for degenerative spondylolisthesis in the lumbar spine seems promising for obtaining not only good radiographic features but also good clinical results lasting over more than 10 years. Electronic Publication     

Radiographic evaluation of posterolateral lumbar fusion for degenerative spondylolisthesis: long-term follow-up of more than 10 years vs. midterm follow-up of 2-5 years.

Although posterolateral fusion of the lumbar spine without instrumentation has been widely performed for spinal instability caused by degenerative spondylolisthesis in the lumbar spine, few long-term follow-up studies have been reported. We studied ten patients who underwent posterolateral fusion for degenerative spondylolisthesis in the lumbar spine without instrumentation in our hospital, five of whom were followed up for more than 10 years and the other five for 2-5 years. We used radiography to examine their fusion status, instability and degenerative changes at the fusion level, change in the slip, change in lumbar lordosis, and instability and degenerative changes one level above and one level below the fusion. In most of the ten patients, radiographic evaluation demonstrated solid fusion, minimal degenerative changes, and preservation of lumbar lordosis and spinal mobility. Posterolateral lumbar fusion for degenerative spondylolisthesis in the lumbar spine seems promising for obtaining not only good radiographic features but also good clinical results lasting over more than 10 years.     

成人腰椎滑脱症复位程度对临床疗效的影响

目的通过对Ⅱ、Ⅲ度成人腰椎滑脱症患者手术治疗的回顾性临床研究,探讨腰椎滑脱复位程度对临床疗效的影响。方法 2005年1月至2011年6月,72例成人Ⅱ、Ⅲ度腰椎滑脱症患者接受手术治疗。其中Ⅱ度滑脱52例,Ⅲ度滑脱20例;峡部裂性滑脱症24例,退行性腰椎滑脱症48例;男18例,女54例;年龄39~78岁,平均60.2岁。所有患者均行减压、椎弓根螺钉提拉复位固定、椎间或加横突间植骨融合术。以滑脱复位率作为评价腰椎滑脱复位的程度,分别是完全复位组29例,滑脱复位率100%;部分复位组38例,滑脱复位率82.5%;未复位组5例,滑脱复位率0。分别测出三组的术前滑移程度,术后滑移程度;临床疗效根据患者术前术后及末次随访时的视觉模拟疼痛评分(visual analogue scale,VAS)和日本骨科协会(Japanese orthopaedic association,JOA)功能评分进行评价,组间比较采用单因素方差分析,结果采用SPSS 19.0统计软件进行统计学相关性分析。结果 72例患者术后均获得随访,随访24~66个月,平均38个月。临床疗效评价优50例,良14例,可8例,优良率达88.89%。术后与术前VAS评分,术后及末次随访时JOA评分,术后及末次随访时的滑移程度、腰椎滑脱复位率和临床疗效满意率,未复位组与完全复位组和部分复位组两组差异有统计学意义(P0.01)。而三组间2年融合率差异无统计学意义(P0.05)。结论成人腰椎滑脱症复位程度越完全越有利于患者症状解除和明显改善,未复位组原位融合与完全复位和部分复位组临床疗效差异显著。腰椎滑移程度对远期腰椎融合率无明显影响。     

Reconstruction of the lumbar spine using AO DCP plate internal fixation

Augmentation of lumbar spine fusion with internal fixation using pedicle screw systems has gained wide currency because it offers rigid stabilization to foster fusion healing. The AO DCP plate has been employed in Europe as a spinal implant with pedicle fixation using 6.5 mm, full-threaded cancellous bone screws with success. This report details the experience of using this device for lumbar spine fusion in a series of 46 North American patients with a mean follow-up of 1.25 years (range 1-2.5 years). Thirty-one patients had had prior lumbar spine surgery with poor outcomes, and 15 had had no prior surgery. All were treated surgically for lumbar degenerative disease with canal decompression, internal fixation with AO plates, and fusion with autologous bone grafting posterolaterally. Complications included two early and one delayed wound infection; five cases of screw loosening; three cases of screw breakage; and three cases of screw impingement upon a nerve. Results of surgery in 17 patients with failed interbody fusion included good to excellent pain relief in 59%, and solid fusion in 76%. In 14 patients with failed posterior surgery the good to excellent pain relief rate was 79%, and the fusion rate was 86%. In 15 patients undergoing primary surgery there was 89% good to excellent pain relief and a solid fusion rate of 87%. The benefits accruing from augmentation of the fusion with internal fixation using AO DCP plates are positive and justify its continued use. Complications encountered in the early experience have been significantly reduced in subsequent series, indicating the existence of a "learning curve" effect which would mandate specific training of spinal surgeons in the technique.