两种前路减压融合术治疗颈椎间盘突出症的比较

目的对前路颈椎间盘切除减压的碳纤维椎间融合器(cage)植入术与自体髂骨块植骨加钛板固定术治疗单节段颈椎间盘突出症(CDH)进行临床疗效及影像学评估。方法需要手术治疗的单节段CDH患者60例,其中前路减压cage植入术31例,自体髂骨块植骨加钛板固定术29例。术前、术后及随访期间摄X线片,比较两组病例的手术时间、术中出血量、术后并发症、症状改善率、融合时间、融合率、融合节段椎体间高度的维持情况。结果cage植入术较自体髂骨块植骨加钛板固定术手术时间短,出血少(P<0.01)。两组融合节段椎体间高度较术前均明显改善(P<0.01)。两组间症状改善率、融合率无统计学意义(P>0.05)。cage植入术较自体髂骨块植骨加钛板固定术并发症少。结论cage植入术和自体髂骨块植骨加钛板固定术都是前路减压治疗单节段CDH的重要而有效的方法。而cage植入术在减小手术创伤的同时,可以获得同样的临床效果,是治疗单节段CDH理想的术式之一。     

Treatment of multilevel cervical fusion with cages

BACKGROUND: Multilevel cervical discectomy usually requires plate and screw fixation for maintaining the spinal curvature, and increasing the graft fusion rate. However, the use of plate and screw fixation may cause a few complications, such as screw breakage, screw pullout, esophagus perforation, and cord or nerve root injury. In this study, we try to use cages to replace plate function in multilevel cervical fusion. METHODS: From January 1997 to June 2001, there were 180 consecutive cases of multilevel cervical degenerative disease. We randomized them into three groups: Group A (60 patients) underwent anterior discectomy and polyetheretherketone (PEEK) fusion, Group B (50 patients) underwent anterior discectomy, autogenous iliac crest graft (AICG) fusion and plate fixation, and Group C (70 patients) underwent anterior discectomy and AICG only. X-ray of cervical spine was taken every 3 months until fusion was complete. Spinal curvature was measured by lateral view of X-ray. The functional and working status were evaluated by Prolo scale. Blood loss and operation time were recorded, respectively. RESULTS: The total complication rates were 3.3%, 16%, and 54.3% in Groups A, B, and C respectively. The graft complications were evaluated by radiographic findings (graft collapse, nonunion, or dislodged graft). However, only 37.1% of patients (13/35) with graft complications had clinical symptoms (severe neck pain, radicular pain, or neurologic deficits). The fusion rate was better, and the time to fusion was sooner in Groups A and B than Group C, p < 0.001 (chi(2) test). PEEK cage is statistically better than plating group in total complications, p < 0.05. Graft collapse and nonunion were the major graft complications in Group C (AICG without plating). Screw pullout, and screw breakage were the main causes of plating complication. Blood loss was minimum in Group A, p < 0.05. Spinal lordosis increased by a mean of 4.61 +/- 2.93 mm and 1.68 +/- 5.02 mm in Groups A and B, respectively, but spinal kyphosis increased by a mean of -2.09 +/- 4.77 mm in Group C. Group A had a statistically better Prolo scale than Group C, p < 0.0001. CONCLUSIONS: Both PEEK cage without plating and AICG with plating are good methods for interbody fusion in multilevel cervical degenerative diseases. They increase spinal lordosis and graft fusion rate, and cause fewer surgical complications. However, PEEK cage is preferred in our study for multilevel fusion, because it has the fewest complication rates and the least amount of blood loss.     

内窥镜技术在颈椎前路手术中的应用

目的：探讨内窥镜下颈椎前路减压植骨融合术的手术技巧与疗效。方法：2002年8月～2005年3月应用内窥镜下颈椎前路减压植骨融合术治疗20例颈椎疾患患者，均应用自制不同型号椎间旋转撑开器及特制不同角度、不同大小的网形与方形刮匙行前路椎间盘切除，单纯PEEK cage植骨融合8例，PEEK cage植骨融合加钛板内同定2例，单纯钛cage植骨融合3例，钛cage植骨融合加钛板内同定2例，椎间植骨融合加钛板内同定5例，随访观察治疗效果。结果：术后随访3～12个月，平均7个月。患者症状体征及神经功能均明显改善。术后影像学检查手术部位减压彻底。1例发生钛cage松动，其余椎间高度无丢失，维持颈椎正常生理曲度。结论：通过对椎间盘镜部分器械和技术的改进，将其应用于颈椎前路椎间盘切除、椎间融合内同定术治疗颈椎病及颈椎间盘突出症可取得满意的效果。     

椎间融合器和植骨钢板融合治疗颈椎间盘突出症的临床对照研究

目的比较柱形椎间融合器(Soliscage)、金属Cage和植骨钛钢板融合治疗颈椎间盘突出症的临床疗效。方法对2002年2月~2005年5月治疗的64例颈椎间盘突出症患者进行回顾性分析。将其分为3组采用Soliscage治疗者为A组,男15例,女5例,年龄38~76岁;20例(30节段),术前JOA评分9~16分,平均11.4分。采用钛合金Cage治疗者为B组,男15例,女6例,年龄37~78岁;21例(23节段),术前JOA评分8~13分,平均10.1分。采用常规前路减压植骨钢板内固定治疗者为C组,男18例,女5例,年龄32~76岁;23例(28节段),术前JOA评分9~14分,平均10.6分。对3组的放射线暴露时间、取髂骨时间、手术时间、出血量、术后并发症发生率、颈椎融合率、症状缓解率和JOA评分改善率等指标进行对比分析。结果术后所有患者均获随访2~15个月,平均12个月。A组取髂骨时间、手术时间和放射线暴露时间分别为4.1±1.7min、55.5±10.3min和4.3±1.2min,B组分别为4.2±1.9min、56.8±12.6min和4.2±1.3min,C组11.5±2.4min、98.3±14.7min和7.8±1.8min;A、B组与C组比较差异有统计学意义(P<0.05),但A、B组间比较差异无统计学意义。C组每节段术中出血量为145.8±19.3ml,显著高于A组65.8±10.2ml和B组67.2±12.3ml,比较差异有统计学意义(P<0.05)。A、B组术后并发症的发生率低于C组(P<0.05),A组和B组椎间高度维持较好,术后3~4个月时融合率达100%,高于C组92.8%,但比较差异无统计学意义(P>0.05)。A组症状缓解率优于B、C组,但比较差异无统计学意义(P>0.05)。术后1年随访,JOA评分A组改善率为81.9%±3.2%,优于B组78.9%±7.3%和C组76.3%±9.4%,但差异无统计学意义(P>0.05)。结论Soliscage治疗颈椎间盘突出的疗效略优于金属Cage和植骨钢板治疗,且操作简便,手术并发症少,临床愈合快。     

颈前路减压支撑融合钢板内固定术治疗脊髓型颈椎病

目的 探讨颈前路减压、椎体间植骨支撑融合或颈椎椎间融合器（钛网或Cage）支撑融合、钢板内固定术治疗脊髓型颈椎病的临床方法及疗效。方法 回顾分析66例脊髓型颈椎病患者行颈前路减压后,分别采取骼骨植骨支撑融合、颈椎间融合器（钛网或Cage）植入支撑融合,钢板内固定术,随访时间平均32个月,采用Zdeblick影像学判定椎体间融合的标准,贾连顺的评定法评定术后临床疗效。结果 在颈前路减压、钢板内固定术治疗脊髓型颈椎病方法中,自体骼骨植骨融合优良率87．5％,供区并发症12．1％,椎间盘退变椎问高度丢失7．6％;颈椎间融合器支撑融合优良率96．1％,无供区并发症和椎问盘退变椎间高度丢失。结论 颈前路减压、椎体间植骨融合或颈椎间融合器支撑融合、钢板内固定术治疗脊髓型颈椎病临床疗效满意。钢板内固定术后颈椎即刻稳定;植骨融合手术操作简单,费用少,但存在供区并发症、椎问高度丢失;椎间融合器融合稳定、牢固,椎间高度丢失少,后者疗效优于前者。     

Anterior cervical allograft arthrodesis and instrumentation: Multilevel interbody grafting or strut graft reconstruction

This retrospective study evaluated a single surgeon's series of patients treated by multilevel cervical disc excision (two or three levels), allograft tricortical iliac crest arthrodesis, and anterior instrumentation. The objective of this retrospective study was to compare fusion success and clinical outcome between multilevel Smith-Robinson interbody grafting and tricortical iliac strut graft reconstruction, both supplemented with anterior instrumentation in the cervical spine. The incidence of nonunion for cervical discectomy and fusion varies widely depending on the number of disc levels involved, type of bone graft used, and whether the anterior grafting is supplemented with instrumentation. An alternative to multilevel interbody fusion is corpectomy and strut grafting, in which the incidence of nonunion has been reported to be 27% with autograft and 41% with allograft. Sixty-four consecutive patients who underwent allograft tricortical iliac crest reconstruction and anterior cervical plating were studied. The average follow-up was 39 months. There were 38 patients in the discectomy and interbody grafting group and 26 patients in the corpectomy and strut graft reconstruction group. Pseudoarthrosis occurred in 42% of the anterior cervical interbody fusion patients and 31% of the corpectomy patients. Nonunion in two-level interbody fusions occurred in 36% of the patients as compared to 10% for patients with one-level corpectomies; while 54% of patients with three-level interbody fusions and 44% of patients with two-level corpectomies were noted to have pseudoarthrosis. Higher percentages of nonunion were noted in multilevel interbody grafting than in corpectomy with strut grafting and when more vertebral levels were involved. These radiographic and clinical findings underscore the shortcomings of multilevel anterior cervical allograft reconstruction with plating. Corpectomy may be the preferred method when multiple disc levels are fused. In addition, anterior corpectomy affords decompression of significant osteophytes in a safer and quicker manner. In retrospective studies, there is a need for long-term follow-up before accurate statements can be made about the study population.     

A modified technique for anterior multilevel cervical fusion

 Anterior cervical fusion with interbody bone graft and anterior plating is commonly performed. Unfortunately, the plate has been reported to shield the graft from loading, thus reducing fusion rates. Interbody fusion cages have been effective in the lumbar spine and have gained acceptance in the cervical spine. Twenty-five patients underwent anterior cervical fusion with this modified technique. All patients received anterior diskectomy and corpectomy, placement of an interbody fusion cage packed with corpectomy bone, and application of an anterior cervical plate. Fusion was defined by radiographic evidence of trabecular bone bridging through the cage. No external bracing was used except soft collars as needed. Pre- and postoperative pain scales were completed and statistically analyzed using paired t tests. There were no cases of pseudoarthrosis or major neurological, vascular, or wound complications. There was one case of mild dysphagia that remained unresolved. Mean operative time was comparable to standard instrumented multilevel cervical fusion surgeries. Visual analogue pain scales were significantly improved following surgery. The advantages of using interbody cages with anterior plating include immediate stability and support, elimination of donor site pain from iliac crest bone autograft, and a decrease in pseudoarthrosis by halving the number of fusion surfaces. Received: November 15, 2000 / Accepted: December 18, 2001     

帽式颈椎椎间融合器的活体实验研究

目的 本研究在活体山羊颈椎上从椎间支撑能力、二期生物力学稳定性及椎间融合组织学方面比较三面皮质骨、Harms椎间融合器（cage）、Carboncage及自行所研制的帽式颈椎椎间融合器（hat　type　cervical　intervertebral　fusion　cage,HCIFC）的术后效果。方法　取32头山羊随机平均分为4组：第1组自体三面皮质髂骨;第2组Harmscage;第3组Carboncage;第4组HCIFC。分别行C3,4椎间盘切除术并分别植入以上内植物。术后共观察12周并测量平均椎间高度（DSH）、椎间角（IVA）及前凸角（LA）,处死后进行影像学、生物力学及组织学评估。结果 术后1周方盒形HCIFC、Carboncage组的平均DSH、IVA及LA要显著大于垂直圆柱体Harmscage和三面皮质骨组（P〈0．05）;术后12周时3个cage组的平均DSH、IVA及LA显著高于三面皮质骨组（P〈0．05）。垂直圆柱体Harmscage轴向旋转和侧屈时平均刚度显著大于其他组（P〈0．001）,轴向旋转时的最大活动度要显著低于其他组（P〈0．05）。与三面皮质骨组相比,3个cage组的椎间融合效果略好。结论HCIFC的椎间支撑能力、生物力学性能及椎间融合效果均适合于临床使用。     

Efficacy and safety of the use of titanium mesh cages and anterior cervical plates for interbody fusion after anterior cervical corpectomy

BACKGROUND: To determine the safety and effectiveness of the use of titanium mesh cages (TMCs) and anterior cervical plates (ACPs) for interbody fusion after anterior cervical corpectomy. METHODS: From June 2001 to June 2003, 15 patients underwent reconstruction with TMCs and ACPs for interbody fusion after anterior cervical corpectomy in our hospital. The mean follow-up is 13.6 months (range, 9-24 months). Subjects included those with cervical degenerative, traumatic, or pathological diseases. Titanium mesh cages were filled with autologous bone grafts taken from the corpectomy and iliac crest bone chips and were all filled with triosite (calcium phosphate ceramics). The patients' observable signs, neurological reconstruction results, and complications were fully and explicitly recorded throughout the procedure. Radiological imaging studies for measurements of coronal and sagittal angles, sagittal displacements, and settling ratio changes were performed to evaluate spinal stability. We used axial cervical computed tomography (CT) and reconstructive sagittal cervical CT to demonstrate interbody fusion within titanium mesh. RESULTS: The alleviation and frequent disappearance of the subjects' original symptoms and the significant neurological recovery obvious in most patients indicated that postoperative spinal stability could be well maintained. No significant differences in mean cage height-related settling rates, mean sagittal displacements, and mean coronal and sagittal angle changes were observed between 1-level and multilevel corpectomy. All patients who received axial and reconstructive sagittal cervical CT scan could demonstrate true interbody fusion within TMC, and no nonunions were present. Cage malplacement was observed in one subject who had neck pain and neck stiffness, rather than from radiculopathy or myelopathy. One subject died of acute myocardial infarction. There were no ceramic-related complications. CONCLUSIONS: Based on preliminary findings from this study, reconstruction involving TMC interbody fusion with ACP fixation after anterior cervical corpectomy serves as an effective and safe method for the treatment of cervical disease.     

In vivo experimental study of hat type cervical intervertebral fusion cage (HCIFC)

The purpose of this study was to compare the characteristics of interbody fusion achieved using the hat type cervical intervertebral fusion cage (HCIFC) with those of an autologous tricortical iliac crest graft, Harms cage and the carbon cage in a goat cervical spine model. Thirty-two goats underwent C3-4 discectomy and fusion. They were subdivided into four groups of eight goats each: group 1, autologous tricortical iliac crest bone graft; group 2, Harms cage filled with autologous iliac crest graft; group 3, carbon cage filled with autologous iliac bone; and group 4, HCIFC filled with autologous iliac graft. Radiography was performed pre- and postoperatively and after one, two, four, eight and 12 weeks. At the same time points, disc space height, intervertebral angle, and lordosis angle were measured. After 12 weeks, the goats were killed and fusion sites were harvested. Biomechanical testing was performed in flexion, extension, axial rotation, and lateral bending to determine the stiffness and range of motion. All cervical fusion specimens underwent histomorphological analyses. One week after operation, the disc space height (DSH), intervertebral angle (IVA) and lordosis angle (LA) of HCIFC and carbon cage were statistically greater than those of autologous iliac bone graft and Harms cage. Significantly higher values for DSH, IVA and LA were shown in cage-treated goats than in those that received bone graft over a 12-week period. The stiffness of Harms cage in axial rotation and lateral bending were statistically greater than that of other groups. Radiographic and histomorphological evaluation showed better fusion results in the cage groups than in the autologous bone group. HCIFC can provide a good intervertebral distractability and sufficient biomechanical stability for cervical fusion.     

Polyetheretherketone (PEEK) cage filled with cancellous allograft in anterior cervical discectomy and fusion

From July 2004 to June 2005, 19 patients with 25 discs underwent anterior cervical discectomy and interbody fusion (ACDF) in which polyetheretherketone (PEEK) cages were filled with freeze-dried cancellous allograft bone. This kind of bone graft was made from femoral condyle that was harvested during total knee arthroplasty. Patient age at surgery was 52.9 (28-68) years. All patients were followed up at least 1 year. We measured the height of the disc and segmental sagittal angulation by pre-operative and post-operative radiographs. CT scan of the cervical spine at 1 year was used to evaluate fusion rates. Odom's criteria were used to assess the clinical outcome. All interbody disc spaces achieved successful union at 1-year follow-up. The use of a PEEK cage was found to increase the height of the disc immediately after surgery (5.0 mm pre-operatively, 7.3 mm immediately post-operatively). The final disc height was 6.2 mm, and the collapse of the disc height was 1.1 mm. The segmental lordosis also increased after surgery (2.0 degrees pre-operatively, 6.6 degrees immediately post-operatively), but the mean loss of lordosis correction was 3.3 degrees at final follow-up. Seventy-four percent of patients (14/19) exhibited excellent/good clinical outcomes. Analysis of the results indicated the cancellous allograft bone-filled PEEK cage used in ACDF is a good choice for patients with cervical disc disease, and avoids the complications of harvesting iliac autograft.     

改良颈椎前路单椎体次全切除融合术并单节段颈椎前路椎间盘切除融合术治疗多节段脊髓型颈椎病

目的 探讨改良颈椎前路单椎体次全切除融合术(ACCF)并单节段颈椎前路椎间盘切除融合术(ACDF)治疗连续3节段椎间盘突出并椎管狭窄的脊髓型颈椎病(CSM)的可行性、安全性和有效性.方法 2010—2018年本院收治3节段椎间盘突出并椎管狭窄的CSM患者379例,其中133例采用传统单节段ACCF并ACDF治疗,并以长...     

钛网联合Cage配合自锁钛板治疗多节段颈椎间盘突出症

目的总结钛网联合Cage配合自锁钛板在多节段颈椎间盘突出症前路椎间盘切除后椎体间融合的效果。方法回顾性分析2004年9月-2007年6月采用钛网联合Cage配合自锁钛板治疗18例多节段颈椎间盘突出症的临床效果。男11例，女7例；年龄32～75岁，平均54岁。病程6个月～15年，平均5．8年。肢体感觉障碍16例；四肢肌力2级3例，3级12例，4级1例，5级2例；锥体束征阳性16例；大小便障碍13例：性功能障碍8例；伴神经根型症状7例。其中连续的多节段12例，不连续的多节段6例。术前JOA评分为（8．30&#177;1．21）分。X线片及MRI示不同程度椎间盘退变、突出、颈髓受压。术前X线片测得病变椎间隙高度为（6．40&#177;0．87）mm。结果术后切口均I期愈合。患者均获随访，随访时间6～36个月，平均18个月。术后早期四肢运动功能恢复较好，感觉障碍恢复较慢；术前肌张力高者术后肌张力下降；患者肢体灵活性改善。手术椎间隙于术后3～6个月获骨性融合，未见塌陷。术后6个月，JOA评分为（12．60&#177;0．78）分，改善率51．8％，与术前比较差异有统计学意义（P〈0．05）：病变椎间隙高度为（8．20&#177;0．46）mm，与术前比较差异有统计学意义（P〈0．05）。按照Odom临床效果分级进行评价，优17例，良1例。无死亡，无脊髓、神经、气管及食道损伤等并发症发生，无Cage移位及松动发生。结论对于多节段颈椎间盘突出症，钛网联合Cage配合自锁钛板固定更具优势。     

Anterior cervical fusion with interbody cage containing β-tricalcium phosphate augmented with plate fixation: a prospective randomized study with 2-year follow-up

A variety of bone graft substitutes, interbody cages, and anterior plates have been used in cervical interbody fusion, but no controlled study was conducted on the clinical performance of β-tricalcium phosphate (β-TCP) and the effect of supplemented anterior plate fixation. The objective of this prospective, randomized clinical study was to evaluate the effectiveness of implanting interbody fusion cage containing β-TCP for the treatment of cervical radiculopathy and/or myelopathy, and the fusion rates and outcomes in patients with or without randomly assigned plate fixation. Sixty-two patients with cervical radiculopathy and/or myelopathy due to soft disc herniation or spondylosis were treated with one- or two-level discectomy and fusion with interbody cages containing β-TCP. They were randomly assigned to receive supplemented anterior plate (n = 33) or not (n = 29). The patients were followed up for 2 years postoperatively. The radiological and clinical outcomes were assessed during a 2-year follow-up. The results showed that the fusion rate (75.0%) 3 months after surgery in patients treated without anterior cervical plating was significantly lower than that (97.9%) with plate fixation (P < 0.05), but successful bone fusion was achieved in all patients of both groups at 6-month follow-up assessment. Patients treated without anterior plate fixation had 11 of 52 (19.2%) cage subsidence at last follow-up. No difference (P > 0.05) was found regarding improvement in spinal curvature as well as neck and arm pain, and recovery rate of JOA score at all time intervals between the two groups. Based on the findings of this study, interbody fusion cage containing β-TCP following one- or two-level discectomy proved to be an effective treatment for cervical spondylotic radiculopathy and/or myelopathy. Supplemented anterior plate fixation can promote interbody fusion and prevent cage subsidence but do not improve the 2-year outcome when compared with those treated without anterior plate fixation. This study was supported by Shanghai Natural Science Foundation (No. 044119626).     

零切迹颈椎前路融合固定系统与传统融合器钢板内固定系统治疗单节段颈椎间盘突出症的病例对照研究

目的 :比较零切迹颈前路椎间融合固定系统(Zero-p)与传统钛板联合cage融合内固定术治疗单节段颈椎间盘突出症的临床疗效。方法:对2011年8月至2014年3月接受颈前路椎间盘切除植骨融合内固定术的139例单节段颈椎间盘突出症患者的临床资料进行回顾性分析,根据已采取的不同术式分为A,B两组,其中A组63例,行前路椎间盘切除与Zero-P融合内固定;B组76例,行前路椎间盘切除椎间cage融合与钢板内固定。分别于手术前后对患者进行JOA评分、Odom功能评级;采用电视透视吞咽研究(videofluorographic swallowing study,VFSS)评估患者椎前软组织厚度;采用Bazaz吞咽困难分级评估患者术后吞咽困难的发生率。术后12个月时采用颈椎正侧位X线及CT检查评估植骨融合情况,采用MRI检查评估临近节段退变情况。比较两组患者术中出血量、手术时间、手术前后JOA评分、Odom评级及VFSS中的椎前软组织厚度、术后患者吞咽困难发生率(Bazas评分)、椎体间融合率、邻近节段退变发生率。结果:手术前后两组患者的JOA评分、Odom功能评级差异比较无统计学意义(P0.05);两组患者术前VFSS中的椎前软组织厚度比较差异无统计学意义(P0.05);两组患者手术时间及术中出血量比较差异无统计学意义。两组患者VFSS中的椎前软组织厚度、吞咽困难发生率在术后第2天,术后3、6个月及末次随访时差异均有统计学意义(P0.05)。术后1年所有患者获植骨融合,两组融合率比较差异无统计学意义(P0.05)。A组8例(12.7%)出现邻近节段退变,B组19例(25%)出现临近节段退变,两组比较差异有统计学意义(P0.05)。结论:应用零切迹颈椎前路椎间融合固定系统和传统钛板联合cage融合内固定治疗单节段颈椎间盘突出症均可取得满意疗效,前者术后吞咽困难和临近节段退变发生率较低,中长期疗效有待进一步观察。     

Implantation of a distractible titanium cage after cervical corpectomy: technical experience in 20 consecutive cases

BACKGROUND: This prospective observational study was undertaken to investigate the advantages, the safety, and the drawbacks of reconstructing a cervical corpectomy with a distractible corpectomy cage. According to the author's literature search, this is the second clinical report on a distractible cervical corpectomy cage. METHOD: 20 Consecutive patients underwent a single- or multi-level cervical corpectomy for spondylotic myelopathy, traumatic fracture, or tumor. The corpectomy defect was reconstructed by means of a distractible titanium cage, and local bone from the corpectomy was layed around the cage for fusion. An anterior cervical plate and/or a posterior lateral mass or pedicle screw fixation was added in all patients. The average follow-up was 14 months, and all patients had at least 12 months of follow-up. FINDINGS: No hardware failure occurred in any of the patients. Construct stability was achieved in 19 out of 20 patients (95%) at 12 months postoperatively. The mean regional lordosis was 1 degrees preoperatively, 9 degrees postoperatively, and 7 degrees at the follow-up. Mean neck pain on a VAS was 3.9 preoperatively, and 2.6 at 12 months. There were three perioperative complications: transient neurological worsening in one patient, one transient vocal cord paralysis, and persistent dysphagia in one patient. CONCLUSION: A single- or multi-level cervical corpectomy can be safely and effectively reconstructed by a distractible titanium cage and local bone graft in combination with anterior cervical plating and/or posterior lateral mass/pedicle screw fixation. Potential advantages of this technique are an unforced cage insertion in its non-distracted position, press-fitting the cage into the corpectomy defect through cage distraction, correction of kyphosis or preservation of local lordosis through cage distraction, and the absence of donor site morbidity. However, the stability rate in the current series did not exceed the fusion rates of auto- or allografts.     

Bone graft incorporation in radiographically successful human intervertebral body fusion cages.

STUDY DESIGN: Biopsies were obtained from within radiographically successful human intervertebral body fusion cages to document the histology of remodeling bone graft. OBJECTIVES: The purpose of this study is to describe the tissue within successful human interbody cages with special reference to the viability of bone and the presence or absence of debris particles. SUMMARY OF BACKGROUND DATA: The use of interbody fusion cages is gaining rapid acceptance, but there is little histologic documentation of the nature of tissue within successful human interbody fusion cages. METHODS: Needle biopsies were obtained of tissue within radiographically successful intervertebral body fusion cages at the time of pedicle screw removal for back pain or fusion of adjacent spinal level in nine spinal levels of eight patients. Preoperative diagnoses of these eight adult patients included disease conditions in the sagittal plane: spondylosis (5), degenerative disc disease (6), failed laminectomy and discectomy (2), radiculopathy (1), and spondylolisthesis (1). In all cases the cages had been packed with autograft (iliac crest 7, local 1) at the time of insertion. Cage implantation was performed with anterior (anterior lumbar interbody fusion 4, corpectomy and plate fixation 1), and posterior (posterior lumbar interbody fusion 4), segmental instrumentation (plate 1, or pedicle screws 8). All cases except one cervical case had posterolateral fusion or bilateral facet fusion. The cages were composed of carbon fiber-reinforced polymer (Brantigan cage; DePuy AcroMed, Raynham, MA, n = 5) or titanium mesh (Harms Cage; DePuy AcroMed, Raynham, MA, n = 4). Cages had been in situ from 8 to 72 months (mean 28 months). All nine biopsies from eight patients were obtained from within the center of the cages. Specimens were decalcified, routinely embedded in paraffin, stained with hematoxylin and eosin, and viewed qualitatively with transmitted and polarized light. RESULTS: All needle biopsies were obtained from within the center of the cages, and no patient developed spinal instability after the biopsy. All nine biopsies showed small fragments of necrotic bone associated with viable bone and restoration of hematopoietic bone marrow. Numerous cement lines demarcated the edges of previous cycles of remodeling. The ratio of necrotic to viable bone varied greatly among cases. Small particles of debris were associated with four of the five carbon-fiber cages and one of the four specimens from titanium cages, but there was no visible bone resorption or inflammation. CONCLUSIONS: Autogenous bone graft was incorporated in these radiographically successful human intervertebral body fusion cages. A few debris particles were observed, but there was no histologic evidence of particle-induced bone resorption or inflammation.     

Anterior cervical discectomy with hydroxylapatite fusion

The outcome of microscopic anterior cervical discectomy with iliac crest interbody fusion in a group of 75 patients was compared with that of microscopic anterior cervical discectomy with synthetic hydroxylapatite fusion in a group of 84 patients. The rate of relief of myelopathy (70%) was similar in both groups, but those who underwent synthetic fusion had better long-term relief of radiculopathy, less need for a second operation at the same or an adjacent level, no resorption of the bone plug, comparable spinal alignment and stability, and the elimination of complications at the iliac crest donor site. The data suggest that hydroxylapatite fusion may be equal or superior to autologous iliac crest interbody fusion for anterior cervical disc surgery.     

A cost analysis of two anterior cervical fusion procedures

Multilevel anterior cervical discectomy and fusion (ACDF) remains a difficult problem. A recently described surgical technique for multilevel ACDF has eliminated the morbid complications associated with harvesting iliac crest bone graft (ICBG) while maintaining the advantages of using autologous bone graft. A matched-pairs t test was used to compare the estimated costs of 27 ACDFs using titanium surgical mesh, local autologous bone graft, and anterior plate instrumentation with 27 ACDFs using ICBG and plate fixation. The three variables considered were cage cost, operating time (cost), and hospitalization cost. The estimated costs for the two surgical procedures were not significantly different. Thus, the time saved by not harvesting an ICBG was comparable to the cost of the cage. Harvesting ICBG also increased the morbidity rate by 22%.     

颈椎椎体次全切除钛网钢板固定治疗颈椎管狭窄症

目的探讨颈椎椎体次全切除钛网钢板固定治疗颈椎管狭窄症的疗效。方法对确诊为颈椎管狭窄症患者62例,采用颈前路椎体次全切除钛网植骨钢板固定,对比手术前后患者的JOA评分,分析术前、术后及随访时的动力位片,观察钛网、钢板的位置及颈椎前凸角的变化。结果获得完整随访的患者42例,术后随访6～48个月（平均24个月）,6～8个月均获得植骨融合。术后颈椎前凸角改善明显,钛网及钢板位置稳定,JOA评分在术后获得较显著提高（P〈0.05）。结论颈椎椎体次全切除钛网钢板固定治疗颈椎管狭窄症近期疗效肯定,是一种值得推广的术式,但该术式应严格掌握其适应证。