Does rigid instrumentation increase the fusion rate in one-level anterior cervical discectomy and fusion?

BACKGROUND CONTEXT: Although plate fixation enhances the fusion rate in multilevel anterior cervical discectomy and fusion (ACDF), debate exists regarding the efficacy of nonplating to rigid plate fixation in one-level ACDF. PURPOSE: To determine the efficacy of nonplating to rigid plate fixation in regards to fusion rate and clinical outcome in patients undergoing one-level ACDF with autograft. STUDY DESIGN: A review of 69 consecutive patients who underwent one-level ACDF with autograft and with or without rigid anterior cervical plate fixation. PATIENT SAMPLE: Sixty-nine patients who underwent one-level ACDF (mean age, 45 years) were evaluated for radiographic evidence of fusion (mean, 14 months) and for clinical outcome. All patients received tricortical iliac crest autografts. Disc space distraction was 2 mm, the grafts were inserted with the cortical surface positioned anteriorly, and each graft was countersunk 2 mm from the anterior vertebral border. Thirty-eight patients underwent nonplated ACDF and 31 patients underwent plated ACDF. Eighteen Orion (Sofamor-Danek, Memphis, TN), eight Atlantis (Sofamor-Danek) and five PEAK polyaxial (Depuy-Acromed, Rayham, MA) anterior cervical plating systems were used. Rigid plate fixation was used in all patients with instrumentation. Postoperatively, hard collars were worn 6 to 8 weeks in nonplated patients and soft collars were worn for 3 to 4 weeks in plated patients. Twenty-four patients were smokers (54.2% nonplating; 45.8% plating) and work-related injuries entailed 23 patients (47.8% nonplating; 52.2% plating). OUTCOME MEASURES: Fusion was assessed based on last follow-up of lateral neutral, flexion and extension radiographs. Radiographs were evaluated blindly to assess fusion and instrumentation integrity between nonplated and plated patients. Clinical outcomes were assessed with the Cervical Spine Outcomes Questionnaire and also assessed on last follow-up as excellent, good, fair or poor based on Odom's criteria. METHODS: Fusion rate and postoperative clinical outcome were assessed in 69 patients who underwent one-level ACDF with autograft and with or without rigid anterior plate fixation. Additional risk factors were also analyzed. Statistical significance was established at p<.05. RESULTS: Sixty-six patients (95.7%) achieved a solid fusion (100% nonplated; 90.3% plated). Nonunions occurred in three patients (1 smoker; 2 nonsmokers) with Orion instrumentation. Slight screw penetration into the involved and uninvolved interbody spaces occurred in one patient who was a nonsmoker and did not achieve fusion. One superficial cervical wound infection was noted in a nonplated patient. No other intraoperative or postoperative complications were noted. No statistically significant difference was noted between nonplating to rigid plating upon fusion rate (p>.05). All nonunions occurred at the C5-C6 level. Mean estimated intraoperative blood loss was significantly greater in plated patients (p=.043). Revision surgery involved 9.7% of the plated patients, whereas none of the nonplated patients required reoperation. Postoperative clinical outcome was assessed in all patients (mean, 21 months). Excellent results were noted in 18.8%, good results in 72.5% and fair results in 8.7% of the patients. Nonunion patients reported satisfactory clinical outcome. No statistical significance was noted between clinical outcome of fused and nonfused patients, the presence of a work-related injury and the use of plating (p>.05). Demographics and history of smoking were not factors influencing fusion or clinical outcome in this series (p>.05). The effect on fusion by various plate types could not be discerned from this study. CONCLUSION: A 100% and 90.3% fusion rate was obtained for one-level nonplated and plated ACDF procedures with autograft, respectively. The effects of smoking or level of fusion could not be discerned from these one-level cases. Excellent and good clinical outcome results were obtained for 91.3%. Nonplating or rigid plate fixation for ACDF in properly selected patients to treat radiculopathy with or without myelopathy has a high fusion rate and yields a satisfactory clinical outcome. Although controversy exists as to the efficacy of rigid plate fixation in one-level ACDF, solid bone fusion can be adequately obtained without plate fixation and instrumentation-related complications can be avoided. In line with the literature, plate fixation should be reserved for patients unwilling or unable to wear a hard orthosis postoperatively for an extended period of time or for those patients who seek a quicker return to normal activities. Proper patient selection, meticulous operative technique and postoperative care is essential to promote optimal graft-host incorporation.     

微创与开放经椎间孔椎体间融合术治疗单节段腰椎病变的Meta分析

目的:对微创与开放经椎间孔椎体间融合术(TLIF)治疗单节段腰椎病变的临床疗效进行Meta分析。方法:计算机检索Pub Med、Web of Science、Cochrane Library、中国生物医学文献数据库、中国知网全文数据库、万方数据库等文献数据库,检索的主题词为"微创(minimally invasive、MIS或mini-open)、开放(open)及经椎间孔椎体间融合术(transforaminal lumbar interbody fusion,TLIF)",检索时间和语言未作限制。纳入关于微创与开放TLIF治疗单节段腰椎病变的对照研究文献。使用纽卡斯尔-渥太华量表(NOS)来进行文献质量评价与特征描述。利用Review Manager 5.1统计学软件进行数据分析。本研究选择的评价指标包括手术相关性指标(手术时间、术中出血量、术后引流量、术中放射时间、术后卧床时间、住院时间、住院总费用),术后腰痛/下肢痛视觉模拟评分法(VAS),术后Oswestry功能障碍指数(ODI),并发症,翻修手术例数和末次随访融合率。结果:经过筛选共纳入18篇文献,其中5篇前瞻性队列研究,12篇回顾性队列研究,仅1篇随机对照试验,共1437例,微创组691例,开放组746例。质量评价提示纳入文献均属高质量队列研究(NOS评分5~9分)。微创TLIF与开放TLIF比较,前者术中出血量、术后引流量、卧床时间、住院时间、住院总费用均明显少于后者(P0.01);术后3d及末次随访腰痛VAS评分改善优于后者(P0.00001);术中放射时间明显多于后者(P0.0001);在手术时间、并发症发生率、翻修手术率、末次随访融合率、术后下肢痛VAS评分及ODI方面,两者差异均无统计学意义(P0.05)。结论:与开放TLIF相比,微创手术创伤小,出血量少,恢复早,术后腰背痛程度较轻的优势,且术后下肢痛的改善及并发症发生率相当,但术中放射时间较长。     

单节段颈椎间盘置换术对相邻颈椎节段退变的影响

目的比较单节段人工颈椎间盘置换术(CDA)与单节段颈椎前路减压融合术(ACDF)对相邻颈椎节段退变的影响。方法收集自2007-02—2011-08共150例纳入队列研究。行CDA 45例、ACDF 105例。比较2组术前、术后颈椎疼痛视觉模拟评分(VAS法)、颈椎功能障碍指数(NDI)、日本骨科协会(JOA)评分、手术节段活动度(ROM)评价疗效。常规拍摄颈椎正侧位、过伸过屈位X线片,或行颈椎CT或(和)MRI进一步检查,以改良的Hilibrand法评价相邻节段退变程度。结果 2组均获得随访4年。ADR可以明显保留节段运动,但二者在术后VAS评分、NDI评分、JOA评分,及相邻节段退变率上差异无统计学意义(P0.05)。结论 CDA减少相邻节段的退变并不明确,仍需要大量严格随机对照试验的长时间、大样本观察。     

非配对设计二值资料一水平多重Logistic回归分析

本文的目的是介绍非配对设计二值资料一水平多重Logistic回归模型的构建与求解方法。基于SAS软件分别对以列联表和数据库形式呈现的定性资料进行全面分析,并得出了4个对提高模型拟合优度很有价值的结论:第一,若资料以列联表形式呈现,应拟合"加权"Logistic回归模型;第二,若资料中包含定量自变量,不适合将其定性化;第三,若资料中包含定量自变量,应依据定量自变量和二值自变量产生出派生自变量;第四,若资料中有定性自变量时,必须将多值名义或有序自变量进行哑变量变换,不需要依据二值自变量产生出派生自变量。     

单节段脊柱去松质骨截骨与双节段经椎弓根截骨矫正强直性脊柱炎后凸畸形的临床效果比较

目的 :比较单节段脊柱去松质骨截骨(vertebral column decancellation,VCD)与双节段经椎弓根截骨(pedicle subtraction osteotomy,PSO)矫正强直性脊柱炎后凸畸形的临床效果,探索两者之间的差异性。方法 :2007年1月~2013年3月共有33例需行40°~65°截骨的强直性脊柱炎后凸畸形矫形术后患者纳入研究,其中男31例,女2例,年龄19~56岁(35.2±8.9岁),后凸畸形以胸腰段后凸为重,脊柱胸腰段后凸Cobb角42.3°±15.2°,腰段前凸Cobb角4.4°±16.4°。A组15例行单节段VCD,B组18例行双节段PSO,记录手术前后胸椎后凸角、胸腰段后凸角、腰椎前凸角、矢状面垂直轴、骨盆入射角、骨盆倾斜角、骶骨倾斜角、截骨角度、脊柱侧凸研究学会(Scoliosis Research Society,SRS)-22量表评分、Oswestry功能障碍指数(Oswestry disability index,ODI)、术中出血量及手术时间,比较两组观察指标及其变化量之间的差异。结果 :A组截骨部位分别为T12 1例、L2 6例、L3 8例,截骨角度46.7°~64.2°(53.6°±6.7°);B组截骨部位分别为L1、L3 13例,T12、L2 4例,T12、L3 1例,截骨角度45.1°~63.9°(55.6°±6.0°)。固定节段于截骨部位近端及其远端延伸至少2个椎体,B组截骨部位之间椎体均固定。A、B两组患者术后均未出现神经系统并发症。A、B两组术后胸腰段后凸角、腰椎前凸角、骶骨倾斜角、骨盆倾斜角、矢状面垂直轴、ODI、SRS-功能评分、SRS-疼痛评分、SRS-外观评分、SRS-心理评分、SRS-满意度评分均较术前明显改善(P0.05),A组术后胸椎后凸角与术前相比差异无统计学意义(P0.05),B组术后胸椎后凸角与术前相比变小且差异有统计学意义(P0.05)。两组观察指标对比,除胸椎后凸角变化量、术中出血量和手术时间两组间有统计学差异(P0.05)外,余均无统计学差异(P0.05)。结论:对于需行40°~65°截骨角度的强直性脊柱炎后凸畸形患者,单节段VCD可取得与双节段PSO相似的矫正效果,且术中出血量更少,手术时间更短,在重建矢状面平衡与改善生活质量方面效果满意。