Difference in canal encroachment by the fusion mass between anterior cervical discectomy and fusion with bone autograft and anterior plating,and stand-alone cage

We conducted a prospective randomized study comparing stand-alone cage and bone autograft and plate implants in anterior cervical discectomy and fusion (www.clinicaltrials.gov, NCT01011569). Our interim analysis showed autologous bone graft with plating was superior to a stand-alone cage for segmental lordosis. During this analysis, we noted a difference in canal encroachment by the fusion mass between the two fusion groups. A narrow cervical spinal canal is an important factor in the development of cervical spondylotic myelopathy, therefore this unexpected potential risk of spinal cord compression necessitated another interim analysis to investigate whether there was a difference in canal encroachment by the fusion mass between the two groups. Patients had a minimum 1 year of follow-up. The Neck Disability Index, neck and arm pain Visual Analog Scales and lateral radiographs, including bone fusion patterns, were evaluated. Twenty-seven (16 males, 11 females, mean age 54.8 years) and 31 (24 males, seven females, mean age 54.5 years) patients were in the cage and plate group, respectively. Both groups improved after surgery. Fusion began at 2.6 months and 1.3 months and finished at 6.7 months and 4.0 months in 24 (88.9%) and 28 (90.3%) patients in the cage and plate group, respectively. Encroachment into the spinal canal by the fusion mass was significantly different between the fusion types, occuring in 21 (77.8%) patients in the cage group versus six (19.4%) in the plate group (p = 0.003). There was a high incidence of spinal canal encroachment by the fusion mass in the stand-alone cage group, possibly limiting use in narrow spinal canals.     

前路椎间盘摘除合并cage融合固定术治疗颈椎病的临床研究

目的　总结颈前入路显微椎间盘摘除术合并人工椎间融合器 (cage)融合固定术治疗颈椎病的临床经验。方法　借助显微镜和高速磨钻对 38例颈椎病患者进行颈前入路显微椎间盘摘除术 ,采用cage融合后并使用钛板系统固定 ;术中同时采用体感诱发电位 (SEP)进行监护。结果　 38例病人术后均无发生严重的并发症 ;随访 8～2 4个月 ,影像学资料证实 :脊髓和神经根减压明显 ,cage融骨良好 ,内固定钛板位置准确 ;术后JOA评分均恢复至 15分以上 ,无症状恶化或复发者。结论　前路椎间盘摘除合并cage融合固定术治疗颈椎病 ,手术创伤小 ,无供区并发症 ,术后恢复快 ,手术成功率高。     

Recombinant human bone morphogenetic protein-2 versus iliac crest bone graft in anterior cervical discectomy and fusion: Dysphagia and dysphonia rates in the early postoperative period with review of the literature

Recombinant human bone morphogenetic protein-2 (rhBMP-2) is a growth factor utilized to stimulate bone development in several clinical scenarios. Although the U.S. Food and Drug Administration approved this therapeutic modality for only two applications, it is frequently used off-label in anterior cervical discectomy and fusion (ACDF) procedures as an alternative to iliac crest bone graft (ICBG), the prior standard of care. This usage has been a source of controversy in the medical community due to evidence of increased rates of postoperative edema and dysphagia. This retrospective cohort study investigates two groups of 200 patients having undergone ACDF, one using rhBMP-2 and the other using ICBG, to evaluate the incidence of complications in the early postoperative period. A significant reduction in average length of stay was found in the rhBMP-2 cohort (1.40 days) compared to the ICBG cohort (1.85 days) as well as a significantly increased rate of dysphagia (25.5% in rhBMP-2 vs. 15% in ICBG; p = 0.01). An increased rate of dysphonia was observed among patients undergoing revision surgery (25.0%) compared to primary surgery (1.6%), but stratification by number of levels, gender, and smoking status yielded no differences in complication rates. Our evaluation of two large cohorts along with review of the literature on the topic sheds light on potential benefits and risks of rhBMP-2 in ACDF procedures. Further investigation is warranted to determine if clinical gains outweigh the potential harms of rhBMP-2 use in this setting.     

外视镜下行颈椎前路椎间盘切除融合术治疗颈椎病的疗效

目的探讨外视镜下行颈椎前路椎间盘切除融合术(ACDF)治疗颈椎病的有效性和安全性。方法回顾性分析2017年3月至2019年3月复旦大学附属中山医院神经外科收治的15例颈椎病患者的临床资料,所有患者均行外视镜下ACDF。术后行临床随访和影像学随访,以患者的Odom评分和日本骨科协会(JOA)颈椎评分评估手术疗效。结果15例患者(19个节段)的手术用时为(100±6)min(80~160 min),术中出血量为(75±10)ml(40~150 ml)。椎间盘融合比例为19/19。1例患者术后发生一过性声音嘶哑,无一例死亡。所有患者均获随访,随访时间为(11.3±1.7)个月(3~27个月)。术后3个月的Odom评分结果表明,非常满意12例,满意3例。15例患者术后3个月的JOA颈椎评分为(15.8±0.2)分,高于术前的(13.3±0.4)分(t=5.8,P<0.01)。所有患者术后的症状均明显缓解,脊髓功能明显改善。结论外视镜下行ACDF治疗颈椎病的效果良好,且并发症少,值得在临床上推广应用。     

Use of the clavicle in anterior cervical discectomy/corpectomy fusion procedures: cadaveric feasibility study

Introduction Graft sources for cervical fusion procedures include synthetic materials, donor grafts, and autologous bones such as the iliac crest. Considering the data that autologous bone grafts seem to generate the best results for fusion, the next logical step is to seek alternative donor sites so as to attempt to reduce the morbidity associated with these procedures. To our knowledge, autologous clavicle has not been explored as a potential source for cervical fusion. Therefore, the following study was performed to verify the utility of this bone for these procedures. Materials and methods Seven adult cadavers were used for this study. In the supine position, a standard surgical approach and dissection to the anterior cervical spine were performed. Specimens underwent a standard discectomy or corpectomy with placement of harvested ipsilateral clavicle previously dissected. An anterior cervical plating system was next placed over these sites using standard techniques. Measurements of the harvested clavicle were made. Results The results of our morphometric analysis were as follows: An average of 5 cm of bone was easily removed from the middle one third of the clavicle. No gross injury was found to vicinal neurovascular structures. The middle one third of the clavicle offered sufficient bone for the one to two segments fused in our study with remaining bone for at least two additional segments. The mean diameter of this part of the clavicle was 1.2 cm. Conclusions Based on our cadaveric study, such a bony substitute as autologous clavicle might be a reasonable alternative to the iliac crest for use in anterior cervical fusion procedures.     

Stand-alone interbody cage versus anterior cervical plate for treatment of cervical disc herniation: Sequential changes in cage subsidence

Anterior cervical discectomy and fusion with an autogenous iliac bone graft is the gold standard treatment for cervical disc herniation. However, autologous bone grafts obtained from the anterior iliac crest are associated with significant donor-site morbidity and complications. To decrease bone graft-related problems, several types of interbody fusion cage have been developed and are used widely in clinical practice. We compared the clinical and radiological outcomes for two surgical procedures used to treat cervical disc herniation: the stand-alone interbody cage and autologous iliac bone grafting with an anterior plate. The clinical results did not differ between patients treated with the two procedures. The stand-alone cage was less invasive and had less donor-site morbidity. In patients treated with the bone graft and plate, the alignment of the fused segment was maintained in all but one patient, who exhibited nonunion. In contrast, in the cage-treated group, 44% of patients exhibited loss of lordotic alignment of more than 5 degrees and cage subsidence of 3 mm or more. All cage subsidence occurred within 3 months of surgery. Although the stand-alone cage was a less invasive and more effective procedure to treat cervical disc herniation, surgeons should consider the possible drawbacks of the associated subsidence.     

Outcomes of single-level cervical disc arthroplasty versus anterior cervical discectomy and fusion

Several studies have established the short-term safety and efficacy of cervical disc arthroplasty (CDA) as compared to anterior cervical discectomy and fusion (ACDF). However, few single-center comparative trials have been performed, and current studies do not contain large numbers of patients. We retrospectively reviewed all patients from a single military tertiary medical center between August 2008 to August 2012 who underwent single-level CDA or single-level ACDF and compared their clinical outcomes and complications. A total of 259 consecutive patients were included in the study, 171 patients in the CDA group with an average follow-up of 9.8 (±9.9) months and 88 patients in the ACDF group with an average follow-up of 11.8 (±9.6) months. Relief of pre-operative symptoms was 90.1% in the CDA group and 86.4% in the ACDF group with rates of return to full pre-operative activity of 93.0% and 88.6%, respectively. Patients who underwent CDA had a higher rate of persistent posterior neck pain (15.8% versus 12.5%), and patients who underwent ACDF were at risk for symptomatic pseudarthrosis at a rate of 3.4%. Reoperation rates were higher in the ACDF group (5.7% versus 3.5%). To our knowledge, this review is the largest, non-funded, comparison study between single-level CDA and single-level ACDF. This study demonstrates that CDA is a safe and reliable alternative to ACDF in the treatment of cervical radiculopathy and myelopathy resulting from spondylosis and acute disc herniation.     

椎间盘切除并植骨融合治疗颈椎病

目的：为彻底切除增生骨赘，防止椎间隙塌陷，扩大椎间孔，解除脊髓神经根压迫，提高手术治疗颈椎病疗效。方法：前方入路切除椎间盘，在Ｘ线机监测下彻底磨除增生的椎体后外侧骨赘，以植骨块撑开椎间隙。结果：１６例颈椎病患者术前ＪＯＡ计分８～１２分，平均９．６分。Ｎｕｒｉｃｋ伤残分级Ⅱ～Ⅳ级。术后１１例经１～４年随访，ＪＯＡ计分１５～１７分，平均１６分，恢复率８０％～１００％，平均９３．６％，Ｎｕｒｉｃｋ伤残分级Ｏ～Ｉ级。除１例外余植骨块融合良好。结论：椎间盘切除并植骨融合是治疗颈椎病的有效手段。但本术式不适合于后纵韧带骨化病例。     

Clinical experience using polyetheretherketone (PEEK) intervertebral structural cage for anterior cervical corpectomy and fusion

Anterior cervical corpectomy and fusion (ACCF) is commonly performed for various pathologies involving the cervical spine. Although polyetheretherketone (PEEK) cages have been widely used following anterior cervical discectomy and fusion (ACDF), clinical literature demonstrating its efficacy following ACCF is sparse. A retrospective review of patients enrolled in a prospective database who underwent single/multi-level ACCF was performed. Fifty-nine patients were identified who underwent corpectomy reconstruction with PEEK cages for symptomatic degenerative, neoplastic, infectious, or traumatic pathologies of the cervical spine. Thirty-five patients having at least 6 months follow-up (FU) were included in the final analysis. The mean age of patients was 51 years (range, 18–81 years) with FU ranging from 6 to 33 months (mean, 6.6 months). None of the patients had dysphagia at last FU. There was no implant failure with fusion occurring in all patients. While 57% of patients (20/35) remained stable with no progression of myelopathy, 43% (15/35) improved one (11 patients) or two (four patients) Nurick grades after surgery. The use of PEEK cages packed with autograft or allograft is safe and effective following anterior cervical corpectomy, demonstrating high fusion rates and good clinical results. This synthetic material obviates the morbidity associated with autograft harvest and possible infectious risks of allograft. The wide array of cage dimensions facilitates ease of use in patients of all sizes and appears safe for use in the typical pathologic conditions encountered in the cervical spine.     

3D外视镜辅助前路颈椎间盘切除融合术治疗脊髓型颈椎病的疗效

目的 探讨3D外视镜辅助前路颈椎间盘切除融合术(ACDF)治疗脊髓型颈椎病的效果.方法 回顾性分析2019年1～6月3D外视镜辅助ACDF治疗的15例脊髓型颈椎病的临床资料.术后随访12～16个月,平均(14.40±1.45)个月,采用日本骨科协会(JOA)评分评估神经功能.结果 所有病人均在3D外视镜辅助下顺利完成手...     

Comparison of anterior cervical discectomy and fusion with the zero-profile device versus plate and cage in treating cervical degenerative disc disease: A meta-analysis

Zero-profile device was applied to diminish the irritation of the esophagus in the treatment of cervical degenerative disc disease. However, the clinical application of the zero-profile device has not been testified with clinical evidence. The aim of the meta-analysis was to systematically compare the safety and effectiveness of anterior cervical discectomy and fusion with zero-profile device with plate and cage for the treatment of cervical degenerative disc disease. Electronic searches of PubMed and Embase were conducted up to May 2015. Relevant studies were included. Weighted mean difference (WMD) and 95% confidence intervals (CI) were assessed for continuous data. Risk ratio (RR) and 95% CI were assessed for dichotomous data. P value <0.05 was considered to be significant. Eleven studies were included in the meta-analysis. Compared with plate and cage, zero-p is associated with lower operation time of two-level surgery, less intraoperative blood loss, higher subsidence rate, higher JOA score, lower incidence of dysphagia in short-term (RR: 0.72, 95% CI [0.58, 0.90], P = 0.005, I² = 22%) and long-term (RR: 0.12, 95% CI [0.05, 0.30], P < 0.00001, I² = 0%) and lower Cobb angle of multilevel surgery (WMD: −3.16, 95% CI: [−4.35, −1.97], P < 0.00001, I² = 0%). No significant difference was found in one-level and two-level Cobb angle, fusion rate and operation time of one-level and three-level surgery. Both zero-p implantation and the plate and cage have respective advantages and disadvantages.     

Use of an integrated anterior cervical plate and cage device (PCB) in cervical anterior fusion

The aim of this study is to evaluate an integrated cage and plate device (the plate cage Benezech, PCB) filled with autogenous bone in anterior cervical discectomy and fusion. The fused segment height, lordosis, and fusion were assessed by postoperative radiographic examination at different intervals. Patients were evaluated using Odom’s criteria and the Short Form (SF)-36 Health Survey questionnaire. The mean follow-up duration was 4.1 years. Fusion was achieved in 90.0%, 96.0% and 100% of patients at 3 months, 6 months and at final visit, respectively. The fused segment height and lordosis were restored and maintained. Cage subsidence (3 mm) occurred at one level and settling was observed at three levels. An excellent-to-good result was achieved in 81.8% of patients. The data from the SF-36 questionnaire revealed significant postoperative improvement (p < 0.01) except for social function and mental health. This study suggests that patients instrumented with PCB can obtain good radiographic and clinical results and that PCB is a safe and effective device in cervical anterior fusion.     

Successful anterior fusion following posterior cervical fusion for revision of anterior cervical discectomy and fusion pseudarthrosis

Pseudarthrosis occurs after approximately 2–20% of anterior cervical discectomy and fusion (ACDF) procedures; it is unclear if posterior or anterior revision should be pursued. In this study, we retrospectively evaluate the outcomes in 22 patients with pseudarthrosis following ACDF and revision via posterior cervical fusion (PCF). Baseline demographics, preoperative symptoms, operative data, time to fusion failure, symptoms of pseudarthrosis, and revision method were assessed. Fusion outcome and clinical outcome were determined at last follow-up (LFU). Thirteen females (59%) and 9 (41%) males experienced pseudarthrosis at a median of 11 (range: 3–151) months after ACDF. Median age at index surgery was 51 (range: 33–67) years. All patients with pseudarthrosis presented with progressive neck pain, with median visual analog scale (VAS) score of 8 (range: 0–10), and/or myeloradiculopathy. Patients with pseudarthrosis <12 months compared to >12 months after index surgery were older (p = 0.013), had more frequent preoperative neurological deficits (p = 0.064), and lower baseline VAS scores (p = 0.006). Fusion was successful after PCF in all patients, with median time to fusion of 10 (range: 2–14) months. Eighteen patients fused both anteriorly and posteriorly, two patients fused anteriorly only, and two patients fused posteriorly only. Median VAS neck score at LFU significantly improved from the time of pseudarthrosis (p = 0.012). While uncommon, pseudarthrosis may occur after ACDF. All patients achieved successful fusion after subsequent posterior cervical fusion, with 91% fusing a previous anterior pseudarthrosis after posterior stabilization. Neck pain significantly improved by LFU in the majority of patients in this study.     

The application of a zero-profile implant in anterior cervical discectomy and fusion

We analyzed the clinical efficacy of the Zero-P implant (Synthes GmbH Switzerland, Oberdorf, Switzerland) in the treatment of single level cervical spondylotic myelopathy. The clinical data of 47 patients with single level cervical spondylotic myelopathy were retrospectively analyzed. Twenty-two patients were treated with a Zero-P implant (Group A) and 25 with a titanium plate with cage (Group B) between January 2009 and September 2010. Operative time, intraoperative blood loss, preoperative and postoperative Japanese Orthopaedic Association (JOA) scores and JOA recovery rate, dysphagia incidence and adjacent segment degeneration rate were measured. The mean operative time in Group A and Group B was 98.18 minutes and 105.4 minutes, respectively. The average intraoperative blood loss in Group A and Group B was 87.95 ml and 92.4 ml, respectively. There were no statistical differences in operation time and intraoperative blood loss between the two groups (p > 0.05). The JOA score was significantly improved in the two groups (p < 0.001), and the recovery rate was similar (60.86% for Group A versus 62.95% for Group B, p > 0.05). Dysphagia was experienced by one (4.5%) patient in Group A and eight (32%) patients in Group B, which was significantly different (p = 0.044). There was no statistical significance found in the adjacent level degeneration rates between Group A and Group B (p = 0.330). The Zero-P implant and traditional titanium plate with cage are effective treatments for single level cervical spondylotic myelopathy, but the Zero-P implant has a lower dysphagia incidence.     

Complication of an interbody biopolymer graft extruded orally after anterior cervical discectomy and fusion.

Graft extrusion is a dilemma that follows anterior cervical discectomy. We report on a case of an extrusion of a biocompatible osteoconductive polymer (BOP) graft extruded orally after anterior cervical discectomy and fusion. This case highlights the potential dangers in slipped or dislodged grafts and stresses the importance of investigation of patients whose symptoms might be attributable to graft extrusion. Furthermore, all dislodged implants should be removed to prevent further complications.     

Anterior cervical discectomy and interbody fusion with porous tantalum implant. Results in a series with long-term follow-up

Few papers have been published about the anterior cervical discectomy and fusion (ACDF) with implant of porous tantalum cages. These studies included patients submitted to operation at a single level. To our knowledge, we report the results of the largest series of ACDF with implant of porous tantalum cages. Our series included patients operated at a single or double level with a long follow-up (FU). We also discuss the pertinent literature. Clinical and outcome data of 99 consecutive patients (47 men, 52 women) submitted to ACDF with implant of porous tantalum cages (Trabecular Metal TM-S Cervical Fusion Device, Zimmer Spine, Minneapolis, MN) from June 2007 to September 2012, were retrospectively reviewed. Mean FU was 67.47 ± 19.63 months. The changes in pain were assessed using the Visual Analogue Scale (VAS). Patients were evaluated pre-operatively and at FU with the Short Form-36 Score Health Survey Version 2.0 (SF-36v2) for Physical Health and Mental Health Scores and the Neck Disability Index. We globally found a statistically significant improvement of all evaluated scores. Patients operated at two levels experienced a statistically significant improvement of all scores, with no statistical difference compared to patients operated at one level. No major complications occurred post-operatively and at FU. Only one patient (operated at two level) experienced an infection during FU. We conclude that ACDF with porous tantalum cages is a safe procedure, with long term clinical benefits (also in patients operated at two levels) and a very low rate of complications.     

内窥镜下前路颈椎间盘切除碳素纤维Cage置入治疗颈椎病

自1955年Robinson和Smith首次应用颈前路椎间盘切除、椎间融合以来,该技术取得了良好的临床效果。当前,内窥镜途径在治疗颈椎病方面有较好的临床效果,且Cage在临床上亦有较广泛的应用     

Determinants of initial bone graft volume loss in posterolateral lumbar fusion

Bone graft volume decreases postoperatively without known etiology. We sought to determine the bone graft volume over time in 15 consecutive patients undergoing a single-level, instrumented, posterolateral lumbar fusion for degeneration causing mechanical pain or spondylolisthesis, and to identify factors associated with bone graft resorption. Following Institutional Review Board approval, a retrospective analysis was performed. Immediate and 3-month postoperative lumbar spine CT scans were imported into imaging software for volumetric analysis. We found that the 15 patients averaged approximately 11% graft volume loss at 3 months postoperatively. All patients exhibited volumetric graft loss on each side (range, 0.3-45%). A paired t-test revealed that immediate postoperative graft volume on a patient’s left or right did not reflect graft volume on that side 3 months postoperatively (p = 0.0008). Gender, age, history of prior operation, history of regular exercise, body mass index, level fused, operative time, initial graft volume, and laterality did not influence percentage volumetric loss (p = 0.1-0.5). Interestingly, people who smoked cigarettes (range, 10-40 pack-years) exhibited 27% graft loss, compared to 7% in those who did not (Spearman p = 0.009 graft loss versus pack-years smoked). We concluded that bone graft exhibited resorption 3 months postoperatively on both sides of all patients in this series, and that smoking was significantly associated with increased bone graft resorption.     

Outpatient anterior cervical discectomy and fusion: A meta-analysis

Anterior cervical discectomy and fusion (ACDF) performed as an outpatient has become increasingly common for treating cervical spine pathology, largely due to its cost savings compared with inpatient ACDF. Nearly all outpatient ACDF patient reports have originated from single-center studies, with the procedure yet to be addressed via a meta-analysis of the peer-reviewed literature. The Entrez gateway of the PubMed database was used to conduct a comprehensive literature search for articles published in English up to 3/9/16. Data from studies meeting inclusion criteria (minimum of 25 patients, control group of inpatient ACDF patients, non-duplicative data source) was then categorized and assimilated for analysis. Seven studies met inclusion criteria, encompassing a 21-year timespan. Each provided Oxford Center for Evidence-Based Medicine Level 3 evidence. The studies yielded a total of 2448 outpatient ACDF patients; only 125 (5.1%) originated from studies published prior to 2011. Single-level surgery occurred in 63.8% of patients, with 0.5% extending beyond two-level fusions. The overall complication rate was 1.8% (mean follow-up of 141.2 days); only 2% of patients required readmission. In conclusion, outpatient ACDF has become increasingly popular, with more than 95% of patients represented by studies published since 2011. Nearly two-thirds of outpatient ACDFs underwent single-level fusion, with virtually none undergoing 3+ level ACDF. Outpatient ACDF is safe, with a low readmission rate and complication rates comparable to those (2–5%) associated with inpatient ACDF. These findings support an argument for increasing ACDFs performed on an outpatient basis in appropriately selected patients.     

Cervical anterior hybrid technique with bi-level Bryan artificial disc replacement and adjacent segment fusion for cervical myelopathy over three consecutive segments

This study aimed to assess the preliminary clinical efficacy and feasibility of the hybrid technique for multilevel cervical myelopathy. Considering the many shortcomings of traditional treatment methods for multilevel cervical degenerative myelopathy, hybrid surgery (bi-level Bryan artificial disc [Medtronic Sofamor Danek, Memphis, TN, USA] replacement and anterior cervical discectomy and fusion) should be considered. Between March 2006 and November 2012, 108 patients (68 men and 40 women, average age 45 years) underwent hybrid surgery. Based on the Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), and Odom’s criteria, the clinical symptoms and neurological function before and after surgery were evaluated. Mean surgery duration was 90 minutes, with average blood loss of 30 mL. Mean follow-up duration was 36 months. At the final follow-up, the mean JOA (± standard deviation) scores were significantly higher compared with preoperative values (15.08 ± 1.47 versus 9.18 ± 1.22; P < 0.01); meanwhile, NDI values were markedly decreased (12.32 ± 1.03 versus 42.68 ± 1.83; P < 0.01). Using Odom’s criteria, the clinical outcomes were rated as excellent (76 patients), good (22 patients), fair (six patients), and poor (four patients). These findings indicate that the hybrid method provides an effective treatment for cervical myelopathy over three consecutive segments, ensuring a good clinical outcome.