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.     

使用椎弓根钉固定的PLF和PLIF的生物力学比较

目的比较在失稳腰椎使用椎弓根钉固定的侧后方融合和经后路椎体间融合的生物力学效果。方法10具L3—S1人新鲜尸体腰椎标本用于实验。完整脊柱测试后,于L4,5后方行连续性破坏,并用椎弓根钉固定(PS)和椎体间cage行以下各脊柱重建组：①完整脊柱及PS组。②两侧关节突关节内侧切除及PS组。③两侧关节突关节完全切除及PS组。④椎间盘部分切除及PS组。⑤椎间盘部分切除及PS／cage组。各组分别行载荷量6Nm的前后屈曲实验,记录并比较固定椎间L4,5的刚度值、L4椎弓根钉的折曲应变量、及上位相邻关节L3,4的运动范围(ROM)。结果固定椎间L4,5的刚度值：椎间盘部分切除及PS以外的所有重建组的脊柱刚度均显著大于完整脊柱组,椎间盘部分切除及PS／cage组的脊柱刚度显著大于其他固定组。L4螺钉的折曲应变量：椎间盘部分切除及PS组L4螺钉折曲应变量显著大于其他固定组,而椎间盘部分切除及PS／cage的螺钉应变量在所有重建组中最小。L3,4的ROM：与完整脊柱相比,所有重建组都显著增大了L3,4的ROM。更重要的是椎间盘部分切除及PS／cage组的ROM明显大于单纯PS组。结论若脊柱前方承载能力尚存,使用PS的侧后方融合可获得足够的力学稳定性。在此情况下,椎体间融合会进一步加大相邻关节的活动范围,故不应使用。当脊柱前方丧失其承载能力,单纯PS的脊柱刚度低,椎弓根钉的应力显著增大。对此种病例,cage的使用可增加重建脊柱的初期稳定性,有利于降低后方固定器械的应力。     

极外侧型腰椎间盘突出症的诊治分析

目的探讨极外侧型腰椎间盘突出症（FLLDH）的诊治特点和术式选择。方法23例FLLDH患者中,其中椎间孔型14例,椎间孔外型9例。23例患者中腰痛8例（占31％）,下肢痛21例（占91％）,直腿抬高试验10例（43％）,CT或MRI可清楚地显示位于椎间孔或孔外缘突出的椎间盘。分别采用经后正中入路椎板扩大开窗术,椎间孔切开和椎弓根内固定植骨融合术,或经肌间隙入路髓核摘除术。疗效按Macnab标准评估。结果22例患者经平均3．6年随访,优15例,良4例,可3例,无差,优良率达86％。在可的3例中,其中1例为经旁正中入路手术,另2例为椎间孔型FLLDH,周缘钙化。结论症状和体征表现常以较高神经节段受损为主,下肢痛是主要症状,CT或MRI是诊断的主要依据。对椎间孔型FLLDH可采用椎板间扩大开窗术;对椎间孔外型FLLDH则需行经椎间孔切开术并辅以经椎弓根内固定植骨融合,亦可采用经肌间隙入路髓核摘除术。     

Minimally invasive 360° instrumented lumbar fusion

A retrospective preliminary study was undertaken of combined minimally invasive instrumented lumbar fusion utilizing the BERG (balloon-assisted endoscopic retroperitoneal gasless) approach ¶anteriorly, and a posterior small-incision approach with translaminar screw fixation and posterolateral ¶fusion. The study aimed to quantify the clinical and radiological results using this combined technique. The traditional minimally invasive approach to the anterior lumbar spine involves gas insufflation and provides reliable access only to L5-S1 and in some cases L4-5. A gas-mediated approach yields many technical drawbacks to performing spinal surgery. A minimally invasive posterior approach involving suprafascial pedicle screw instrumentation has been developed, but without widespread use. Translaminar facet fixation may be a viable alternative to transpedicular fixation in a 360° instrumented fusion model. Past studies have shown open 360° instrumented lumbar fusion yields high arthrodesis rates. The study examined the cases of 46 patients who underwent successful 360° instrumented lumbar fusion using a combined minimally invasive approach. Anterior lumbar interbody fusion (ALIF) at one or two levels was performed through the BERG approach; a gasless retroperitoneal approach to the lumbar spine allowing the use ¶of standard anterior instrumentation. Posteriorly, all patients underwent successful decompression, translaminar fixation, and posterolateral fusion at one or two levels through ¶one small (2.5-5.0 cm) incision. Results showed mean hospital stay of 2.02 days; mean combined blood loss was 255 cc; and mean pain relief was 56%, with 75.5% of patients reporting good, excellent, or total pain relief. Forty-two of 46 patients (93.2%) achieved a solid fusion ¶24 months after surgery. A total of 47% of all patients working prior to surgery returned to work following surgery. The study showed that minimally invasive 360° instrumented lumbar fusion, when performed utilizing these approaches, yields a high rate of solid arthrodesis (93.3%), good pain relief, short hospital stays, low blood losses, accelerated rehabilitation, and a quick return to the workforce. The BERG approach offers technical advantages over the traditional gas-mediated laparoscopic approach to the anterior lumbar spine.     

Surgical treatment of cervical destructive spondyloarthropathy (DSA)

STUDY DESIGN: Sixteen patients with hemodialysis-associated cervical spine disorders underwent surgical treatment. After analysis of the surgical results, the optimum surgical procedures for these disorders were discussed. OBJECTIVE: To evaluate the surgical results of cervical spine disorders associated with long-term hemodialysis and to propose the optimum surgical procedures for successful outcomes. SUMMARY OF BACKGROUND DATA: There have been few reports regarding surgical results of hemodialysis-related cervical spine disorders. Surgical treatment for this disorder is still challenging. METHODS: Sixteen patients with hemodialysis-associated cervical spine disorders were treated surgically. Duration of hemodialysis ranged from 8 to 27 years (average, 17 years). Before surgery, 14 patients showed severe cervical myelopathy, and the other 2 had radiculopathy in the upper extremities. Ten patients with marked destructive changes underwent circumferential reconstructive surgery involving pedicle screw fixation, anterior strut bone grafting, and posterior and/or anterior decompression. Two patients with cervical radiculopathy underwent posterior nerve root decompression by foraminotomy and fusion by pedicle screw fixation or spinous process wiring. The remaining four patients without spinal instability underwent posterior decompression by open-door laminoplasty. RESULTS: Two patients died during follow-up. Follow-up periods in the surviving 14 patients ranged from 25 months to 92 months (average, 53 months). Marked neurologic recovery was obtained in all patients after surgery. Successful spinal fusion was obtained in all patients except one who underwent posterior fusion by spinous process wiring. Progressive destructive changes with significant instability at the adjacent mobile segments were observed in two patients who underwent circumferential fusion with a pedicle screw system more than 2 years after the initial surgery. CONCLUSIONS: The pedicle screw system achieved a high fusion rate in reconstructive surgery of cervical destructive spondyloarthropathy, even in the presence of severe bone fragility.     

Minimally invasive 360° instrumented lumbar fusion

A retrospective preliminary study was undertaken of combined minimally invasive instrumented lumbar fusion utilizing the BERG (balloon-assisted endoscopic retroperitoneal gasless) approach ¶anteriorly, and a posterior small-incision approach with translaminar screw fixation and posterolateral ¶fusion. The study aimed to quantify the clinical and radiological results using this combined technique. The traditional minimally invasive approach to the anterior lumbar spine involves gas insufflation and provides reliable access only to L5-S1 and in some cases L4-5. A gas-mediated approach yields many technical drawbacks to performing spinal surgery. A minimally invasive posterior approach involving suprafascial pedicle screw instrumentation has been developed, but without widespread use. Translaminar facet fixation may be a viable alternative to transpedicular fixation in a 360° instrumented fusion model. Past studies have shown open 360° instrumented lumbar fusion yields high arthrodesis rates. The study examined the cases of 46 patients who underwent successful 360° instrumented lumbar fusion using a combined minimally invasive approach. Anterior lumbar interbody fusion (ALIF) at one or two levels was performed through the BERG approach; a gasless retroperitoneal approach to the lumbar spine allowing the use ¶of standard anterior instrumentation. Posteriorly, all patients underwent successful decompression, translaminar fixation, and posterolateral fusion at one or two levels through ¶one small (2.5–5.0 cm) incision. Results showed mean hospital stay of 2.02 days; mean combined blood loss was 255 cc; and mean pain relief was 56%, with 75.5% of patients reporting good, excellent, or total pain relief. Forty-two of 46 patients (93.2%) achieved a solid fusion ¶24 months after surgery. A total of 47% of all patients working prior to surgery returned to work following surgery. The study showed that minimally invasive 360° instrumented lumbar fusion, when performed utilizing these approaches, yields a high rate of solid arthrodesis (93.3%), good pain relief, short hospital stays, low blood losses, accelerated rehabilitation, and a quick return to the workforce. The BERG approach offers technical advantages over the traditional gas-mediated laparoscopic approach to the anterior lumbar spine.     

椎弓根内固定加植骨治疗腰椎滑脱症疗效分析

目的探讨后路应用椎弓根钉复位固定、减压、椎体间或后外侧植骨融合治疗腰椎滑脱症的临床疗效。方法对38例腰椎滑脱症（Ⅰ～Ⅱ度）行后路椎板减压,应用HOIST、GSS、USS三种不同内固定方法对腰椎滑脱椎体进行复位固定,椎体间或后外侧植骨融合。结果随访6～24个月,临床优良率87％,6～12个月复查X线片均显示椎体间骨性融合。结论上述三种椎弓根螺钉系统能有效撑开提拉滑脱椎体,复位满意,固定力强,采用椎体间或后外侧植骨融合能有效提高植骨融合率,增加脊柱的稳定性。     

椎弓根钉辅助下后外侧融合在退变性腰椎管狭窄症手术中的应用

目的探讨退行性腰椎管狭窄症(degenerativelumbarspinestenosisDLSS)的特点、椎弓根钉辅助下的后外侧融合手术要点及其在退变性腰椎管狭窄症减压术中的作用和意义。方法回顾性分析2000年1月～2003年12月间59例腰椎管狭窄症患者的临床症状、椎管减压和椎弓根钉辅助下的后外侧植骨融合的手术和术后随访情况,手术结果通过问卷式调查由患者进行自我评价,评价内容分为:腰痛、腿痛、日常活动水平、是否服用止痛药物四个方面进行。结果59例患者随访6～48个月,平均22.5个月,8例患者1年后失访。其中治疗效果优21例(35.6%),良32例(54.2%),可4例(6.8%),差2例(3.4%)。术中术后的并发症主要有:神经根损伤、硬膜囊撕裂、FBSS(FailedBackSurgerySyndrome)、ASD(AdjacentSegmentDisease)、椎弓根钉断裂等。结论DLSS包括多部位狭窄性病理改变,术中减压应当按照一定的步骤全面减压。椎弓根钉辅助后外侧融合可以提供腰椎即刻稳定,提高了远期融合率,使得滑脱椎体复位并保持椎间高度,减少椎管狭窄的进展和再发,从而提高手术的治疗效果。     

Functional outcome after posterolateral spinal fusion using pedicle screws: comparison between primary and salvage procedure

Lumbar spinal fusion is a commonly performed surgical procedure, yet both the indications for its performance and its results remain controversial. It is generally believed that apart from situations where obvious measurable instability exists, a repeat surgical procedure such as spinal fusion does not improve the functional outcome in more than an average of 50% of cases. The aim of this study was to analyse functional outcome after posterolateral lumbar or lumbosacral spinal fusion, comparing primary and salvage procedures. It was designed as a prospective case/referent study with a 2-year follow-up. A total of 39 patients underwent a short posterior fusion with Cotrel-Dubousset (CD) pedicle screw fixation after earlier surgery of the lumbar spine. Two patients were erroneously omitted from the study at the index, so 37 patients were included in the salvage group. In the same period, 69 patients underwent lumbar fusion with pedicle screw fixation (CD) as primary surgery (referent group). Functional outcome was assessed by means of the Dallas Pain Questionnaire preoperatively and 1 and 2 years postoperatively. Fusion rates were determined by ordinary X-ray evaluation by two independent observers. Patients who had undergone previous spinal surgery had a significant improvement in functional outcome in terms of daily activity, work and leisure-time activities and anxiety/depression. With regard to social functioning, a significantly inferior outcome was found after the salvage procedure. The return-to-work rates at 2 years after surgery were 50% in the salvage group and 53% in the referent group. There was a significant correlation between radiological evaluation of the fusion mass and the functional outcome. The fusion rate was 76% in the salvage group and 72% in the referent group. This study demonstrates that a posterolateral spinal fusion can be effectively used as a salvage procedure. The functional and radiological outcome of the patients with revision surgery did not differ from those of the group of patients who underwent primary surgery. There was, however a clear indication of inferior social functioning after revision surgery. Received: 29 November 1997 Accepted: 22 January 1998     

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。     

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.     

椎弓根内固定并后外侧融合治疗老年腰椎管狭窄症

目的探讨椎弓根螺钉内固定并后外侧融合治疗老年腰椎管狭窄症的临床疗效。方法对98例经非手术治疗无效的老年（〉60岁）腰椎管狭窄症患者行全椎板切除减压,植入椎弓根螺钉,并行后外侧融合。结果98例均获得随访,时间15～60个月。根据Nakai标准：优72例,良21例,可5例。结论老年腰椎管狭窄常伴有不稳及关节突增生内聚,在充分减压的基础上,行椎弓根钉内固定并后外侧融合,疗效满意。     

棘突椎板作为骨源椎间植入在下腰椎椎间融合中的应用

目的探讨腰椎后路棘突椎板作为骨源椎间植入加椎弓根钉系统固定在下腰椎椎间融合中的可行性和临床效果。方法应用自体棘突椎板作为骨源椎间植入加椎弓根钉系统固定下腰椎98例，其中椎间盘脱出症30例，椎间盘突出症复发11例，腰椎不稳45例，椎管狭窄12例。结果10例失访，88例术后随访12—56个月，腰腿痛症状消失或明显减轻，腰椎间融合好，椎间隙高度无明显减少。结论棘突椎板作为骨源椎间植入加椎弓根钉系统固定在下腰椎的应用具有操作简单、安全、可靠及融合效果好的优点。     

Clinical evaluation and computed tomography scan analysis of screw tracts after percutaneous insertion of pedicle screws in the lumbar spine

STUDY DESIGN: An examination of the accuracy of percutaneous pedicle screw placement in the lumbar spine. Using computed tomography scan analysis after implant removal, the screw tracts could be analyzed regarding the degree and direction of screw dislocation. OBJECTIVES: To investigate the misplacement rate and related clinical complications of percutaneous pedicle screw insertion in the lumbar spine. SUMMARY OF BACKGROUND DATA: The feasibility of the external fixation test has been investigated in several studies. Although pedicle screw misplacement has been reported as one of the main complications, there are no reliable data on the misplacement rate for this difficult surgical procedure. METHODS: In this study, 51 consecutive patients with suspected segmental instability were investigated after external transpedicular screw insertion for the external fixation test. Computed tomography scans of all instrumented pedicles from L2 to S1 were performed after screw removal. The screw tracts were analyzed, and the direction and degree of the pedicle violations were noted. In addition, the screw and pedicle angles were measured. RESULTS: Of 408 percutaneously inserted pedicle screws, only 27 screws (6.6%) were misplaced. There were 19 medial pedicle violations, 6 lateral cortical defects, and only 1 cranial and 1 caudal displacement. With respect to the spinal level, S1 showed the highest misplacement rate, with 11 screw dislocations (12%). After surgery, found two nerve root injuries were found. Only one of the injuries (L4) was related to the malposition of a screw. CONCLUSIONS: This study has shown that percutaneous insertion of pedicle screws in the lumbar spine is a safe and reliable technique. Despite the low misplacement rate of only 6.6%, it should be kept in mind that the surgical procedure is technically demanding and should be performed only by experienced spine surgeons.     

Translaminar screw fixation in the lumbar spine: technique, indications, results

Translaminar screw fixation of the lumbar spine represents a simple and effective technique for short segment fusion in the degenerative spine. Clinical experience with 173 patients who underwent translaminar screw fixation revealed a fusion rate of 94%. The indications for translaminar screw fixation as a primary fixation procedure are: segmental dysfunction, lumbar spinal stenosis with painful degenerative changes, segmental revision surgery after discectomies, and painful disc-related syndromes such as internal disc disruption and lumbar disc herniation with concomitant degenerative changes. As an additional stabilization procedure, translaminar screws can be used to augment anterior fusion or reinforce pedicle systems. Translaminar screw fixation achieves as high fusion rate provided the biomechanical principles of the lumbar spine with an intact anterior column are respected and a meticulous operative technique is employed to enhance bony ingrowth of the graft. Received: 12 January 1998 Revised: 18 March 1998 Accepted: 6 April 1998     

腰椎崩裂性滑脱椎弓根钉复位内固定后外侧植骨融合术

目的　比较分析椎弓根钉复位内固定 后外侧直骨融合术与单纯后外侧植骨融合术治疗腰椎崩裂滑脱的疗效。方法　统计分析我院 1987.1～ 2 0 0 0 .1,97例腰椎崩裂性滑脱病人行椎弓根钉复位内固定 后外侧植骨融合术后 2年的情况 ,内固定于术后一年取出。结果　植骨融合率为 92 .8%(7例未融合 )。腰腿痛症状改善的评价采用 JOA标准 ,术前平均为 15分 ,术后平均为 2 3分 ,(满分为 2 9分 ) ,术前 9.3%(9人 )能参加一般的体力劳动和干家务活 ,术后 75 .3%(73人 )的人能参加一般的体力劳动和干家务活。术前平均滑脱 41%,术后 (去除内固定后一年 )平均滑脱15 %,并发症发生率 6 1%,其中断钉发生率 42 .3%,绝大多数并发症临床上无重要意义。结论　椎弓根钉复位内固定 后外侧植骨融合术能有效矫正腰椎滑脱 ,增加植骨融合率 ,缩短术后卧床休息时间 ,但并发症较单纯后外侧植骨融合术多。     

腰椎滑脱症外科治疗策略选择

目的探讨不同类型腰椎滑脱症及合并症的手术治疗方式、疗效及优缺点。方法2000年2月～2004年4月应用后路椎弓根螺钉复位内固定后，分别采用后外侧植骨融合术、后路椎体间植骨融合术及前路椎体问植骨融合术治疗不同类型腰椎滑脱症及合并症的患者78例，比较术后及随访时疗效、滑脱椎体复位率、椎间隙高度恢复率、植骨融合率以及复位丢失率。结果术后28例Ⅰ度滑脱及37例Ⅱ度腰椎滑脱患者获得解剖复位．9例Ⅱ度滑脱及4例Ⅲ度腰椎滑脱患者矫正至Ⅰ度滑脱。随访时总体优良率为89．72％，42例椎体间植骨患者植骨融合良好，滑脱椎体复位无丢失，椎间隙高度维持良好；36例后外侧植骨者有12例复位丢失，2例椎弓根螺钉松动，2枚椎弓根螺钉断裂：结论对小于Ⅱ度退变性腰椎滑脱合并腰椎管狭窄者宜选用后路椎弓根钉复位固定加后外侧植骨融合术；对峡部裂性腰椎滑脱合并腰椎管狭窄者宜选用后路椎弓根钉固定加椎体间植骨融合术；对Ⅱ度以上峡部裂性单纯腰椎滑脱者以及腰椎滑脱翻修者宜选用后路椎弓根钉固定加前路椎体间植骨融合术。     

Circumferential fusion by posterior approach in lumbosacral instability with or without pedicle screw fixation: a comparison of methods

Lumbosacral circumferential fusion, a method which is widely adopted for the treatment of the different causes of lumbar pain, may be carried out in a single stage by posterior approach, associating interbody fusion with cages with posterolateral fusion. During the same operation, pedicle screw fixation may also be performed. In order to evaluate the need for this final surgical stage represented by pedicle screws, a comparison was conducted in 2 groups of patients affected with lumbosacral instability, treated at the Division of Vertebral Surgery at the Rizzoli Orthopaedic Institute between May 1995 and May 1997. The best clinical results were obtained in the first group (where pedicle fixation was associated). Because of the persistance of pain symptoms, successive pedicle fixation was instead required in a high percentage of patients (45%) in the second group (without pedicle fixation).     

腰椎滑脱手术复位问题的探讨

目的探讨腰椎滑脱手术的复位问题。方法66例腰椎滑脱患者,其中36例(治疗组)采用椎弓根螺钉内固定加椎体间、后外侧植骨及Cage应用治疗,30例(对照组)采用后外侧原位植骨融合手术治疗。对两组术前、术后和最终随访时的X线片测量结果、融合率、断钉率、JOA评分等进行综合评价。结果①治疗组能明显增加椎间隙高度、相对椎间隙高度,提高复位率,降低滑脱率;②治疗组能明显提高术后1年、2年骨性融合率,降低断钉率;③治疗组能明显提高术后JOA评分。结论①腰椎滑脱症手术时滑脱椎体应尽可能复位;②不能过分强调解剖复位,主张部分复位比较安全;③滑脱复位后,术后常出现复位的丢失,如何减少复位的丢失,是需值得重视的问题;④在此基础上彻底的减压是基础,坚强的骨性融合是关键。     

Lumbar interbody fusion using the Brantigan I/F cage for posterior lumbar interbody fusion and the variable pedicle screw placement system: two-year results from a Food and Drug Administration investigational device exemption clinical trial

STUDY DESIGN: A carbon fiber-reinforced polymer cage implant filled with autologous bone was designed to separate the mechanical and biologic functions of posterior lumbar interbody fusion. OBJECTIVES: To test the safety and efficacy of the carbon cage with pedicle screw fixation in a 2-year prospective study performed at six centers under a protocol approved by the Food and Drug Administration, and to present the data supporting the Food and Drug Administration approved indications. SUMMARY OF BACKGROUND DATA: The success of posterior lumbar interbody fusion has been limited by mechanical and biologic deficiencies of the donor bone. Some failures of pedicle screw fixation may be attributable to the absence of adequate load sharing through the anterior column. Combining an interbody fusion device with pedicle screw fixation may address some limitations of posterior lumbar interbody fusion or pedicle screw fixation in cases that are more complex mechanically. METHODS: This clinical study of posterior lumbar interbody fusion with pedicle screw fixation involved a prospective group of 221 patients. RESULTS: Fusion success was achieved in 176 (98.9%) of 178 patients. In the management of degenerative disc disease in patients with prior failed discectomy surgery, clinical success was achieved in 79 (86%) of 92 patients, and radiographic bony arthrodesis in 91 (100%) of 91 patients. Disc space height, averaging 7.9 mm before surgery, was increased to 12.3 mm at surgery and maintained at 11.7 mm at 2 years. Fusion success was notdiminished over multiple fusion levels. These results were significantly better than those reported in prior literature. Although significant surgical complications occurred, those attributable to the implant devices occurred less frequently and generally were minor. CONCLUSIONS: The Brantigan I/F Cage for posterior lumbar interbody fusion and the Variable Screw Placement System are safe and effective for the management of degenerative disc disease.