Minimally-invasive technique for transforaminal lumbar interbody fusion (TLIF)

Minimal access surgical techniques have been described for diskectomy and laminectomy procedures performed through tubular exposures. Tubular exposures, however, restrain visibility to a fixed diameter and require co-axial instrument manipulation. An independent blade retractor system has been developed to overcome the obstacles of working through a tube. Decompression and circumferential fusion can be accomplished through this minimal access exposure via a combination of laminectomy and transforaminal lumbar interbody fusion (TLIF) coupled with minimally invasive pedicle screw fixation. Herein, we describe a minimally-invasive technique for TLIF exposure. Illustrations, intraoperative photographs, and fluoroscopic images supplement this technique. We found that the described minimally-invasive system provides comparable exposure to the traditional-open techniques with the benefits of minimally-invasive techniques. Additionally, it does not have the added constraints of a tubular system. We were able to perform TLIFs without any additional complications. Minimal access decompression and TLIF can be performed safely and effectively using this minimally-invasive system. Besides the retractor system, no additional specialized instruments are required. An operative microscope is not required, in fact, all our cases were performed using operative loupes. The light attachment provides superb visbility without the discomfort of having to wear a headlight. Thus far we have found no added risks or complications using this system. We are currently working on long-term analysis and follow-up to further evaluate this systems efficacy.     

微创通道结合经皮椎弓根螺钉固定治疗腰椎退变的个体化方案选择

目的探讨应用微创通道减压融合结合经皮椎弓根螺钉固定治疗腰椎退行性疾病的初步临床效果及手术方案选择。方法收集2009年8月至2011年7月第四军医大学唐都医院运用微创通道减压融合结合经皮椎弓根螺钉固定治疗并获得随访的64例腰椎退变患者的临床资料。采用Quadrant、Pipeline或Luxor通道系统,经椎间孔腰椎间融合（TLIF）或后路TLIF（PTLIF）入路,行髓核摘除或椎间处理并植入椎间融合器,通道内行椎弓根螺钉固定并安装连接棒。于对侧相应椎体处行椎弓根经皮植入Sextant、vipor或Mantis螺钉固定。微创策略的选择：（1）单侧通道下减压椎间植骨融合,常规椎弓螺钉内固定;（2）一侧通道下减压植骨融合通用螺钉固定 ＋ 对侧通道下通用螺钉固定;（3）一侧通道下减压植骨融合通用螺钉固定 ＋ 对侧经皮螺钉固定;（4）一侧通道下减压椎间植骨融合＋双侧经皮螺钉固定。融合方式包括单节段融合、双节段融合和跨节段融合。观察患者术中出血量、手术时间、术后下床活动时间、住院天数、内固定位置以及术后症状改善情况。结果随访3～22 个月（平均 16 个月）。术中出血量 70～230 mL（平均 90 mL）、手术时间 70～210 min（平均 100 min）、下床活动时间为术后3～10 d（平均5 d）、住院天数5～15 d（平均7 d）。腰痛视觉模拟评分（VAS）和腿痛VAS分别由术前的（9.2 ± 1.4）分和（7.4 ± 1.2）分减少到末次随访的（2.6 ± 0.5）分和（2.2 ± 0.6）分,Oswestry功能障碍指数（ODI）由术前的（57.4 ± 6.4）%降至末次随访的（25.8 ± 4.3）%,差异均有统计学意义（P 〈0.05）。术中、术后X线片和/或 CT 检查显示内固定及融合器位置良好。结论一侧采用微创通道 TLIF 或 PTLIF 入路行单节段或双节段椎间处理融合,或在此基础上行对侧通道下通用螺钉/经皮椎弓根螺钉固定或双侧经皮螺钉固定等个体化方案治疗腰椎退行性疾病,术中出血少,手术时间短,术后可早期下床进行功能锻炼,初步临床效果优良。     

Minimally invasive surgery for the lumbar spine

Minimally invasive spine surgery is a rapidly developing field that has the potential to decrease surgical morbidity and improve recovery compared to traditional spinal approaches. Minimally invasive approaches have been developed for all regions of the spine, but have been best documented for degenerative conditions of the lumbar spine. Lumbar decompression and lumbar interbody fusion are two of the most well-studied minimally invasive surgical approaches. This article will review both the rationale and technique for minimally invasive lumbar decompression and for a minimally invasive transforaminal lumbar interbody fusion (TLIF).     

TLIF术式治疗双节段腰椎滑脱症的临床研究

【摘要】 目的 探讨经椎间孔椎间融合术(TLIF术)式治疗双节段腰椎滑脱症的手术疗效。方法 采用TLIF后路减压、复位、椎弓根螺钉内固定、椎间植骨融合术治疗双节段腰椎滑脱11例,按Lenke标准评价脊柱融合情况,按Henderson标准评价临床疗效。结果 所有病例均获得较大程度的复位,术后随访1~2年,根据Lenke标准评价脊柱植骨融合:A级10例,B级1例;根据Henderson标准评价临床疗效:优9例,良1例,可1例。结论〓TLIF术式治疗双节段腰椎滑脱症,其脊柱融合满意,疗效显著可靠。     

Oblique lateral interbody fusion: The fundamentals for practice

With the avoidance of dissection through the psoas, the oblique lateral interbody fusion (OLIF) offers the spine surgeon a safe option of indirect decompression of the lumbar spine. Described in 1997, the OLIF technique continues to expand its surgical indications with the advent of navigation and robotic technology. This paper will discuss the indications and contraindications of the OLIF procedure while highlighting anatomic considerations, technical aspects, outcomes and complications. From degenerative spondylosis, to sagittal and coronal deformity, the pathology that can be addressed with the OLIF continues to evolve with the aging population. Endplate fracture and subsidence and transient neuropraxias are the most common complications, with an overall rate less than that of transforaminal lumbar interbody fusion (TLIF) or posterolateral interbody fusion (PLIF) with the added benefit of a shorter hospital stay.     

经椎间孔入路腰椎体间融合术治疗腰椎不稳症

目的探讨经腰椎间孔入路行腰椎椎体间植骨融合术治疗腰椎不稳症的手术适应证、技术要点及应用价值。方法自2002年2月~2005年3月,对腰椎不稳56例行腰椎后正中入路,经单侧腰椎间孔行椎体间植骨融合,腰椎后方上下椎板间、棘突间、关节突间植骨,以及相应节段椎弓根钉内固定术。结果56例手术切口均一期愈合,无神经损伤、椎间隙感染和脑脊液漏等并发症。52例经6~37个月随访,平均16个月,未发生内置物断裂、松动移位和椎间隙高度丧失,骨融合率为90·38%。依据日本JOA疗效评定标准,优29例,良16例,可3例,差4例,总优良率为86·5%。结论经腰椎间孔入路椎间植骨融合术(TLIF)治疗腰椎不稳症,不但技术操作可行,而且能明显降低因侵入椎管而带来的各种可能发生的并发症,是治疗退变性腰椎不稳症的有效手术方式。     

显微内镜辅助经皮微创椎间孑L入路腰椎椎体间融合术治疗腰椎退行性疾病

背景：传统开放椎间孔入路腰椎椎体间融合术（transforaminal lumbar interbody fusion,TLIF）由于剥离肌肉广泛及长时间牵拉,可导致部分患者持续性腰背痛。随着脊柱微创技术的发展,采用微创手段实施TLIF技术取得了良好的临床效果,但小切口经扩张通道系统的微创TLIF仍不可避免存在肌肉剥离,需探索更加微创的手术方式。 目的：探讨显微内镜辅助经皮微创TLIF治疗腰椎退行性疾病的近期疗效及安全性。 方法：2010年9月至2011年7月,72例腰椎退行性疾病患者接受了单节段TLIF手术,腰椎失稳症36例,腰椎管狭窄症25例,复发型腰椎间盘突出症11例。采用VIPER经皮椎弓根螺钉系统结合椎间盘镜下TLIF手术32例（微创组）,传统开放TLIF手术40例（开放组）,对两组患者近期临床疗效、并发症、术中射线暴露指标等进行比较。 结果：所有患者均获随访,随访时间6-15个月,平均9个月。两组手术时间无明显统计学差异（P〉0．05）,微创组术中出血量、伤口引流量、住院天数、术后应用镇痛药剂量均明显低于开放组（P〈0．01）;微创组术中射线暴露时间及剂量高于开放组（P〈0．01）;微创组术后疼痛（VAS评分）及ODI功能指数较开放组明显降低（P〈0．01）。微创组出现术中减压错误1例,置钉位置错误1例,导针穿透椎体前壁1例,硬膜撕裂1例;开放组出现术中硬膜撕裂3例,术后伤口浅表感染1例。两组患者均未出现神经损伤并发症。 结论：显微内镜辅助经皮微创TLIF较传统开放手术具有创伤小、出血少、恢复快、住院时间短等优点,具有良好的近期疗效,是治疗腰椎失稳症值得推荐的微创手术方式。     

单侧椎弓根螺钉结合对侧关节突螺钉固定应用于Wiltse入路经椎间孔腰椎椎间融合术的早期疗效观察

背景：目前,多数腰椎微创融合手术多需双侧的旁正中切口以完成椎管减压、椎间融合和后路固定。本研究介绍了一种新的术式,相比以往的方法更加简单、创伤更小,同时固定强度满意。 目的：介绍一种用于微创腰椎经椎间孔融合术（transforaminal lumbar interbody fusion,TLIF）的新的后路内固定技术,并对其安全性和有效性进行评估。 方法：回顾性分析2009年9月至2010年10月,采用单节段的腰椎管减压＋TLIF,同时辅以同侧的椎弓根螺钉固定＋对侧的关节突螺钉固定的40例患者。男20例,女20例,年龄27-82岁,平均57．5岁。手术节段：IA-523例,15-S114例,B-43例。总结临床疗效及并发症。 结果：手术时间97-167min,平均124min。术中出血100-200ml,平均140ml,无输血。术后住院时间3d,平均1-6d。2例患者术后在关节突螺钉侧出现小腿疼痛,行翻修手术取出关节突螺钉,其中1例术后症状缓解,另1例无缓解。无伤口感染和脑脊液漏发生。所有患者术后随访时间均超过10个月,期间融合节段无脊柱不稳发生。 结论：单侧椎弓根螺钉辅以对侧关节突螺钉可以用于单节段Wihse入路的微创腰椎TLIF术,其固定强度满意。与传统的双侧旁正中入路相比,该技术可避免双侧切口的显露和剥离,减少组织损伤,同时具有缩短手术时间、减少出血的优点,但该技术在置入关节突螺钉时需要警惕神经根损伤的风险。     

Lumbar plexopathy following instrumented posterior lumbar interbody fusion: a complication with use of Hohmann’s retractor

Introduction

A series of 12 patients in our centre following single level instrumented posterior lumbar interbody fusion at L4–L5 developed unexplainable motor weakness in the proximal lumbar nerve roots (L2, L3) and numbness of the whole limb, a clinical picture resembling lumbar plexopathy. Even though lumbar plexopathy has been reported following gynaecological procedures and in transpsoas interbody fusion surgeries, there is no literature reporting this complication following conventional instrumented posterior lumbar interbody fusions.

Study design

Retrospective observational study.

Objective

To find the possible mechanism of development of lumbar plexopathy in patients who underwent posterior lumbar interbody fusion surgeries in our centre.

Material and methods

We analyzed retrospectively the medical records, electrophysiological reports of the patients, literatures on the anatomy of lumbar plexus and other literature reporting similar complications. We also dissected lumbar plexus of three cadavers and simulated surgical technique on them to find the mechanism of development of this unusual complication.

Results

We found injury to lumbar plexus that probably occurred intraoperatively with Hohmann’s retractor that was used for retraction of the paraspinal muscles. This theory was favoured by many clinical factors and further confirmed by cadaveric dissections.

Conclusion

We conclude that surgical technique with improper use of Hohmann’s retractor causes traction and compression injury to the lumbar plexus resulting in this complication. We propose proper technique of insertion of Hohmann’s retractor and also recommend use of modified Hohmann’s retractor with shorter tips for spinal procedures to prevent such complication.     

微创手术治疗单节段腰椎管狭窄症的疗效评价

目的:对比微创手术与传统开放手术治疗单节段腰椎管狭窄症的临床效果,评价微创手术治疗腰椎管狭窄症的安全性和有效性。方法:2008年1月～2009年1月收治43例单节段腰椎管狭窄症患者,其中28例采用传统开放减压、后路椎体间融合手术(posterior interbody fusion,PLIF)治疗(A组),15例采用微创减压、经椎间孔融合手术(transforaminal lumbar interbody fusion,TLIF)治疗(B组),比较两组患者的手术时间、术中C型臂X线机照射时间、术中出血量、术后引流量、术后下地时间和术后平均住院时间,并分别采用Oswestrydisability index(ODI)、visual analogue scores(VAS)和X线评价治疗效果。结果:所有患者均获得随访,两组术前一般资料、VAS和ODI评分无显著性差异。B组手术时间和术中透视时间多于A组(P<0.01),而术中出血量和术后引流量B组明显低于A组(P<0.01),术后下地活动时间和术后平均住院日B组明显短于A组(P<0.01)。术后5d时VAS评分B组优于A组(P<0.05),而其他时间相比两组VAS评分与ODI评分相比均无显著性差异(P>0.05),术后X线评价融合率两组亦无显著性差异(P>0.05)。结论:与传统开放手术相比,微创手术治疗单节段腰椎管狭窄症,同样可以获得安全、有效的治疗结果,并且在手术出血量、术后引流量、术后下地活动时间和术后住院时间方面优于传统开放手术。     

Comparison of sagittal contour and posterior disc height following interbody fusion: threaded cylindrical cages versus structural allograft versus vertical cages

OBJECTIVE: Segmental restoration of sagittal contour is recognized as critical for improved long-term success following instrumented lumbar fusions. As such, the use of wedged implants has become more popular. Few studies exist to assess the postoperative lordotic and disc height changes following these varied techniques in spinal fusion. An observational radiographic study examining lumbar sagittal contour and posterior intervertebral disc space height following posterior lumbar interbody fusion (PLIF) or transforaminal lumbar interbody fusion (TLIF) was conducted using vertical cages (VCs), wedged structural allograft (WSA), and threaded cylindrical cages (TCCs). METHODS: Forty-nine consecutive patients (59 spinal segments) were evaluated following single- or two-level interbody fusion with either stand-alone TCCs (n = 18 levels), WSA with posterior transpedicular compression instrumentation (n = 25 levels), or VCs with posterior transpedicular compression instrumentation (n = 16 levels). Standing lumbar radiographs were measured by two independent observers preoperatively, immediately postoperatively (within 1 week), at 6-week follow-up (range 4-8 weeks), and postoperatively (at 1-year follow-up) for segmental lordosis at each level undergoing posterior interbody arthrodesis and posterior intervertebral disc space height to assess indirect nerve root decompression. RESULTS: At the 1-year follow-up, postoperative lordosis was improved in the VC group (+5.3 degrees ; P < 0.005), whereas it decreased in the WSA group (-0.9 degrees ; P = 0.407) and TCC group (-3.5 degrees ; P < 0.005). The posterior disc space height decreased in the VC group (-0.5 mm; P = 0.109), whereas it increased for both the WSA group (+1.2 mm; P = 0.05) and the TCC group (+0.8 mm; P = 0.219). CONCLUSIONS: PLIF with stand-alone TCC and PLIF (or TLIF) with WSA and posterior transpedicular instrumentation results in an increased posterior disc height and thus improved indirect nerve root decompression. PLIF (or TLIF) with VC and posterior transpedicular instrumentation results in an overall decrease in posterior disc height. However, TCC and WSA resulted in a loss of lumbar lordosis, whereas VC resulted in an increase in lumbar lordosis.     

Transforaminal interbody fusion versus anterior-posterior interbody fusion of the lumbar spine: a financial analysis

Lumbar interbody fusion can be performed anteriorly or posteriorly. An anterior approach generally requires an access surgeon and often is combined with a posterior fusion. A traditional posterior interbody fusion can destabilize the spinal motion segment and requires neural retraction. A new surgical technique, a transforaminal lumbar interbody fusion (TLIF), was recently described. It requires minimal neural retraction, and the disk space is exposed posterolaterally with removal of only one facet joint. This study compares the cost of an anterior-posterior one-level lumbar fusion with the cost of the same procedure performed using the TLIF technique. Table 1 lists the specific demographics. A retrospective review of the hospital charges of 80 patients undergoing interbody lumbar stabilization was conducted. The two groups consisted of 40 patients with an anterior-posterior fusion and 40 patients who were fused circumferentially using the TLIF technique. A cost analysis with normalization of 1998 dollars between the two groups was performed. The TLIF group had an average operative time of 213 minutes, compared with 269 minutes for the anterior-posterior group. In addition, an average additional 38 minutes were required to turn the patient from the anterior or posterior position. The average blood loss for the anterior-posterior procedure was 969 mL, compared with 489 mL for the TLIF group. Twenty-three of the anterior-posterior patients received an average of 2.2 units of blood and six of the TLIF patients received an average of 1.3 units. Use of the surgical intensive care unit was much lower in the TLIF group (38 of 40 patients versus 2 of 40 patients). The average length of stay was 6.1 days for the anterior-posterior group compared with an average of 3.3 days for the TLIF group. The average cost of the anterior-posterior patients was $49,085, compared with $33,784 for the TLIF group. Cost analysis between the two groups show the TLIF patients had an average savings of approximately $15,000 per admission. This cost comparison was conducted only for the time of the operative procedure. No attempt was made to analyze rates of fusion between the two groups or ultimate clinic outcome. There were no major complications in either group, and no patient returned to surgery for a lumbar spinal problem at the authors' hospital within 1 year of the index procedure.     

Lumbar Interbody Fusion for Adjacent Segment Disease: An illustrative Case of The Transforaminal Approach (MIS-TLIF)

The scope of minimally invasive surgical (MIS) strategies for management of spinal pathology continues to expand. MIS transforaminal lumbar interbody fusion (TLIF) is an attractive alternative for the management of adjacent level disease. It minimizes approach related morbidities and provides anterior column support at a location where all 3 columns are affected by the adjacent segment degeneration (ASD).Our surgical technique involves the cannulation of the pedicles with K-wires. This is followed by a facetectomy and foraminal decompression with subsequent discectomy and endplate preparation. The cage is inserted followed by pedicle screw placement. To illustrate this technique, we present to you a case of a 56-year-old Female with previous L2–S1 successful arthrodesis, treated with MIS TLIF of L1–L2 for new adjacent segment disc herniation.This chapter describes the effective use of MIS TLIF in the treatment of adjacent segment disease and offers a unique strategy in management of this problem.     

Transforaminal lumbar interbody fusion: surgical technique and results in 24 patients

OBJECTIVE: The advantage of anterior column support and fusion in addition to pedicle fixation in patients with degenerative spinal disorders has become increasingly clear. With the increase in popularity of this treatment, a variety of techniques have been used to achieve the goal of anterior column support, fusion, and segmental instrumentation. Posterior lumbar interbody fusion has been used since the late 1940s in the treatment of degenerative lumbar spine. We evaluated a modification to posterior lumbar interbody fusion called transforaminal lumbar interbody fusion (TLIF). METHODS: A retrospective analysis was performed on 24 patients (9 women, 15 men) who underwent TLIF. The approach involved a unilateral laminectomy and inferior facetectomy at the level of fusion. The interbody fusion was achieved from this unilateral approach by performing discectomy, arthrodesis, and insertion of one or two titanium cages packed with autologous bone. The average age of the patients in this study was 42.6 +/- 12.5 years. Five patients were smokers. Five cases were related to workmen's compensation. Seventeen patients' original symptoms were a combination of low back pain and radiculopathy. Ten patients had had a previous spine operation. RESULTS: Eleven patients had L4-S1 TLIFs. The rest of the patients had a single-level TLIF (L2-S1). Average intensive care unit and floor days were 1.1 +/- 1.0 and 5.8 +/- 2.2 days, respectively. The number of days to ambulation was 2.8 +/- 1.6 days. There were a total of six self-limited complications in 24 patients (including one transient neurological complication). The average follow-up time was 16.9 +/- 9.1 months. Twenty-two patients had solid fusions. A modified Prolo scale (4 worst, 20 best) was used to evaluate the clinical outcome. The average score was 16.1 +/- 4.1. CONCLUSION: TLIF is a reliable and safe technique for interbody support that can be performed with excellent clinical outcome. In the authors' experience, TLIF offers excellent exposure with minimal risk. This applies particularly in cases of repeat spine surgery, in which the presence of scar tissue makes traditional posterior lumbar interbody fusion techniques difficult or impossible. In addition, TLIF seems to be a viable alternative to anteroposterior circumferential fusion and/or anterior lumbar interbody fusion.     

PLIF与TLIF治疗腰椎不稳症的疗效比较

目的对比研究后路腰椎椎体间植骨融合术(posteriorlumbarinterbodyfusion,PLIF)与经腰椎间孔入路腰椎椎间植骨融合术(transforaminallumbarinterbodyfusion,TLIF)治疗腰椎不稳症的疗效。方法1999年2月~2006年3月,217例重度退变性腰椎不稳症患者接受腰椎后路椎间植骨融合,辅以相应节段椎弓根钉内固定术,其中76例经腰椎间孔椎体间植骨融合(TLIF组),另外141例经腰椎管内(硬脊膜外)椎体间植骨融合(PLIF组),比较两组手术方式的临床疗效、植骨融合率及手术并发症。结果217例患者手术切口均一期愈合,无椎间隙感染、下肢深静脉栓塞等并发症。PLIF组128例患者经6~82个月随访,平均64个月,发生硬脊膜撕裂4例,脑脊液漏1例,马尾神经及神经根一过性牵拉损伤3例。TLIF组67例经4~56个月随访,平均36个月,未发生神经损伤等并发症。两组平均手术时间、术中平均出血量、平均住院时间均无明显差异。TLIF组与PLIF组的临床优良率分别为89.86%和86.72%,两者无显著性差异(P>0.05),植骨融合率分别为92.75%和93.75%,两者无显著性差异(P>0.05)。结论经腰椎间孔入路椎间植骨融合术治疗腰椎不稳症,不但技术操作可行,而且能明显降低因侵入椎管而带来的各种并发症,是治疗重度退变性腰椎不稳症的有效手术方式。     

Percutaneous multilevel decompressive laminectomy, foraminotomy, and instrumented fusion for cervical spondylotic radiculopathy and myelopathy: assessment of feasibility and surgical technique

OBJECT: Extensive muscle dissection associated with conventional dorsal approaches to the cervical spine frequently results in local pain, muscle wasting, and temporarily painful and restricted neck movement. The utility of a percutaneous muscle-sparing access technique and specifically modified instrumentation for multilevel posterior cervical decompression and fusion were evaluated. METHODS: Eleven patients (six men, five woman; mean age 72.8 +/- 6.3 years) presenting with refractory neck pain and progressive multilevel cervical radiculopathy and/or myelopathy due to cervical spondylosis with spinal canal and neural foraminal stenosis underwent multilevel laminectomy, foraminotomy, and subsequent instrumented posterior fusion via bilateral or unilateral percutaneous muscle dilation approaches. A novel cannulated polyaxial instrumentation system was used for unilateral transpedicular/translaminar fixation. RESULTS: Significant reduction of Neck Disability Index and Nurick Scale scores and partial or complete recovery of upper extremity radicular deficits was observed during follow-up (mean 14.6 months). Mean procedural blood loss was 45.5 ml, and mean length of stay in hospital was 5.7 days. Fusion was demonstrated in 10 patients between 12 and 14 months postoperatively. Operative exposure and instrumentation were significantly facilitated by specific modifications of retractor/access port systems, surgical instruments, and implants. CONCLUSIONS: Muscle sparing posterior decompression and instrumented fusion constitutes a safe and effective surgical option in a selected subgroup of patients with multilevel cervical spondylotic radiculomyelopathy. Specific modifications in surgical technique, instrumentation, and implants are mandatory for effective achievement of the surgical goals. The use of refined image guidance technology and intraoperative imaging can further improve surgical safety and efficacy.     

Fusion techniques for adult isthmic spondylolisthesis: a systematic review

Introduction

Various fusion techniques have been used to treat lumbar spine isthmic spondylolisthesis (IS) in adults, including anterior lumbar interbody fusion (ALIF), posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), posterolateral fusion (PLF), and circumferential fusion. The objective of this study was to evaluate which fusion technique provides the best clinical and radiological outcome for adult lumbar IS.

Materials and methods

A systematic review was performed. MEDLINE databases and reference lists of selected articles were searched. Inclusion criteria stated that the studies had to be controlled and that they compared clinical and radiological outcomes of various fusion techniques for treating adult IS. Exclusion criteria were use of only one treatment and non-English language articles. Two reviewers independently extracted relevant data from each included study. Statistical comparisons were made when appropriate.

Results

Nine studies that compared two surgical approaches to IS were included in this systematic review. Three were prospective studies, and six were retrospective studies. Two studies compared ALIF with instrumented PLF and ALIF with percutaneous pedicle screw fixation, two studies compared ALIF and TLIF, and five studies compared PLIF and PLF. ALIF was superior to other techniques regarding restoration of disc height, segmental lordosis, and whole lumbar lordosis. TLIF had lower complication rates. ALIF combined with PLF showed lower nonfusion rates than other techniques. However, there were no significant differences in clinical outcomes between any two techniques.

Conclusion

Compared to other fusion techniques, TLIF shows fewer complications, ALIF shows better sagittal alignment, and circumferential fusion showed better fusion rates. It was difficult to make recommendations about the optimal approach because of the methodological variance in the publications.     

Comparison of one-level minimally invasive and open transforaminal lumbar interbody fusion in degenerative and isthmic spondylolisthesis grades 1 and 2

Minimally invasive lumbar fusion techniques have only recently been developed. The goals of these procedures are to reduce approach-related soft tissue injury, postoperative pain and disability while allowing the surgery to be conducted in an effective manner. There have been no prospective clinical reports published on the comparison of one-level transforaminal lumbar interbody fusion in low-grade spondylolisthesis performed with an independent blade retractor system or a traditional open approach. A prospective clinical study of 85 consecutive cases of degenerative and isthmic lower grade spondylolisthesis treated by minimally invasive transforaminal lumbar interbody fusion (MiTLIF) or open transforaminal lumbar interbody fusion (OTLIF) was done. A total of 85 patients suffering from degenerative spondylolisthesis (n = 46) and isthmic spondylolisthesis (n = 39) underwent one-level MiTLIF (n = 42) and OTLIF (n = 43) by two experienced surgeons at one hospital, from June 2006 to March 2008 (minimum 13-month follow-up). The following data were compared between the two groups: the clinical and radiographic results, operative time, blood loss, transfusion needs, X-ray exposure time, postoperative back pain, length of hospital stay, and complications. Clinical outcome was assessed using the visual analog scale (VAS) and the Oswestry disability index. The operative time, clinical and radiographic results were basically identical in both groups. Comparing with the OTLIF group, the MiTLIF group had significantly lesser blood loss, lesser need for transfusion, lesser postoperative back pain, and shorter length of hospital stay. The radiation time was significantly longer in MiTLIF group. One case of nonunion was observed from each group. Minimally invasive TLIF has similar surgical efficacy with the traditional open TLIF in treating one-level lower grade degenerative or isthmic spondylolisthesis. The minimally invasive technique offers several potential advantages including smaller incisions, less tissue trauma and quicker recovery. However, this technique needs longer X-ray exposure time.     

Less invasive posterior fixation method following transforaminal lumbar interbody fusion: a biomechanical analysis.

BACKGROUND CONTEXT: Current surgical trends increasingly emphasize the minimization of surgical exposure and tissue morbidity. Previous research questioned the ability of unilateral pedicle screw instrumentation to adequately stabilize posterior fusion constructs. No study to date has addressed the effects of reduced posterior instrumentation mass on interbody construct techniques. Unilateral surgical exposure for transforaminal lumbar interbody fusion (TLIF) allows ipsilateral pedicle screw placement. Theoretically, percutanous contralateral facet screw placement could provide supplemental construct support without additional surgical exposure. PURPOSE: Identify the biomechanical effects of reduced spinal fusion instrumentation mass on interbody construct stability. STUDY DESIGN: An in vitro biomechanical study using human lumbar spines comparing stability of TLIF constructs augmented by: (1) bilateral pedicle screw fixation, (2) unilateral pedicle screw fixation, or (3) a novel unilateral pedicle screw fixation supplemented with contralateral facet screw construct. METHODS: Seven fresh frozen human cadaveric specimens were tested in random construct order in flexion/extension, lateral bending, and axial rotation using +/-5.0 Nm torques and 50 N axial compressive loads. Analysis of torque rotation curves determined construct stability. Using paired statistical methods, comparison of construct stiffness and total range of motion within each specimen were performed using the Wilcoxon signed ranks test with a Holm-Sidák multiple comparison procedure (alpha=0.05). RESULTS: In flexion/extension, lateral bending, and axial rotation, there were no measurable differences in either stiffness or range of motion between the standard bilateral pedicle screw and the novel construct after TLIF. After TLIF, the unilateral pedicle screw construct provided only half of the improvement in stiffness compared with bilateral or novel constructs and allows for significant off-axis rotational motions, which could be detrimental to stability and the promotion for fusion. CONCLUSIONS: All tested TLIF constructs with posterior instrumentation decreased segmental range of motion and increased segmental stiffness. While placing unilateral posterior instrumentation decreases overall implant bulk and dissection, it allows for significantly increased segmental range of motion, less stiffness, and produces off-axis movement. The technique of contralateral facet screw placement provides the surgical advantages of unilateral pedicle screw placement with stability comparable to TLIF with bilateral pedicle screws.     

微创经椎间孔腰椎椎体间融合术的研究进展

腰椎融合是目前治疗腰椎退变性疾病、腰椎不稳及椎间盘源性等疾病的主要手段.经椎间孔腰椎间融合术(transforaminal lumbar interbody fusion,TLIF)是近年发展起来的新型的腰椎融合术,而随着微创脊柱外科(minimally invasive spinal surgery,MISS)的进步,微创TLIF技术也得到了快速的发展,相对传统开放TLIF又有了更进一步的优势.作者就微创TLIF的适应证与禁忌证,手术方式,发展与优势及微创手术辅助器械等方面的研究现状作一综述.