One- and two-level anterior cervical discectomy and fusion: the effect of plate fixation.

BACKGROUND CONTEXT: The success of arthrodesis for anterior cervical fusion depends on several factors, including the number of surgical levels. Internal fixation putatively improves the arthrodesis rate and outcome. PURPOSE: To provide medium-term follow-up data on the surgical success and patient outcome of one- and two-level anterior cervical discectomies and fusions and to determine the effect that plate fixation has on results. STUDY DESIGN: A prospective study of 40 patients who underwent modified Smith-Robinson anterior cervical discectomy and fusion at one or two operative levels. PATIENT SAMPLE: Forty patients. OUTCOME MEASURES: Odom criteria, Nurick grading system, radiographs. METHODS: Forty patients, with an average age of 44 years (range, 27 to 82), were followed for an average of 51 months (range, 24 to 85). All had an anterior discectomy, burring of the end plates and placement of an autogenous tricortical iliac crest graft at one (20 patients) or two levels (20 patients). Twenty-three were stabilized with the Cervical Spine Locking Plate (Synthes Spine, Paoli, PA), 4 single level, 19 two level. All patients had follow-up office visits with examinations and radiographs. Radiographic union, postoperative pain relief and neurologic recovery were evaluated.RESULTS: Successful arthrodesis of single-level procedures occurred in 11 of 16 unplated and 2 of 4 plated fusions. Primary bony union in the two-level group was achieved in 15 of 19 plated patients and did not occur in the single unplated procedure. Clinically, there were 12 excellent, 5 good, 3 satisfactory and 0 poor outcomes among the single-level procedures. Among the dual-level procedures, there were 10 excellent, 5 good, 3 satisfactory and 2 poor results. Nine of 16 who developed adjacent-level degeneration had pain. Five of the 9 also had nonunions. Of the 40, 3 had fibrous union at final follow-up, and 10 had revision surgery. CONCLUSIONS: The Cervical Spine Locking Plate improved the outcome of two-level procedures to that of uninstrumented one-level fusions. Adjacent-level degeneration is associated with persistent pain, especially if there is also a nonunion. Primary bony union is paralleled by a better clinical outcome.     

Increased fusion rates with cervical plating for three-level anterior cervical discectomy and fusion

STUDY DESIGN: A retrospective review of all patients surgically treated by a single surgeon with a three-level anterior cervical discectomy and fusion with and without anterior plate fixation. OBJECTIVES: To compare the clinical and radiographic success of anterior three-level discectomy and fusion performed with and without anterior cervical plate fixation. SUMMARY OF BACKGROUND DATA: Previous studies of multilevel cervical discectomies and fusions have shown fusion rates to decrease as the number of surgical levels increases. Anterior cervical plate stabilization can provide more stability and may increase fusion rates for multilevel fusions. METHODS: Over a 7-year period, 59 patients were treated surgically with a three-level anterior cervical discectomy and fusion by the senior author. Forty patients had cervical plates, whereas 19 had fusions with no plates. These patients were observed for an average of 3.2 years. Clinical and radiographic follow-up data were obtained. RESULTS: Of the 59 patients, 14 had a pseudarthrosis (7 in each group). The pseudarthrosis rates were 18% (7 of 40) for patients with plating and 37% (7 of 19) for patients with no plating. Although the nonunion rate for unplated fusions was double that of plated fusions, this difference was not statistically significant. There was no statistically significant correlation between pseudarthrosis and gender, age, level of surgery, history of tobacco use, or previous anterior surgery. The fusion rates were improved with the use of a cervical plate. Inferior clinical results were demonstrated in patients with a pseudarthrosis, regardless of the use of a cervical plate. CONCLUSIONS: The addition of plate fixation for three-level anterior cervical discectomy and fusion is a safe procedure and does not result in higher complication rates. In this study, the pseudarthrosis rate was lower for patients with a cervical plate. However, this difference was not statistically significant. Patients treated with cervical plating had overall better results when compared with those of patients treated without cervical plates. Although the use of cervical plates decreased the pseudarthrosis rate, a three-level procedure is still associated with a high nonunion rate, and other strategies to increase fusion rates should be explored.     

Increased fusion rates with cervical plating for two-level anterior cervical discectomy and fusion

STUDY DESIGN: A retrospective review of all patients surgically treated with a two-level anterior cervical discectomy and fusion with and without anterior plate fixation by a single surgeon. OBJECTIVES: To compare the clinical and radiographic success of two-level discectomy and the effect of anterior cervical plate fixation. SUMMARY OF BACKGROUND DATA: Prior studies of multisegment fusions have shown decreased fusion rates correlating with the number of increased levels. The use of anterior plates for single-level cervical fusions is controversial. However, their use in multilevel fusions may be warranted because of the increased pseudarthrosis rates. METHODS: Over a 6-year period, 60 patients were treated surgically with a two-level anterior cervical discectomy and fusion by the senior author. Thirty-two patients had cervical plates, and 28 underwent fusions without plates. These patients were followed for an average of 2.7 years. Clinical and radiographic follow-up evaluations were performed. RESULTS: Of the 60 patients, 7 had a pseudarthrosis. The pseudarthrosis rates were 0% for patients with plating and 25% for those with no plating. This difference was statistically significant (P = 0.003). No correlation of pseudarthrosis with gender, age, level of surgery, history of tobacco use, or the presence of prior anterior surgery was found. There was significantly less graft collapse (P = 0.0001) in the patients without plates in whom pseudarthrosis developed (1.4 mm) than in those who had fusions with plates (0.3 mm). The amount of kyphotic deformity of the fused segment was 0.4 degree in patients with plating compared with 4.9 degrees in those without plating who developed a pseudarthrosis (P = 0.0001). CONCLUSIONS: The addition of plate fixation for two-level anterior cervical discectomy and fusion is a safe procedure with no significant increase in complication rates. The pseudarthrosis rates are significantly higher in patients treated without plate fixation. No nonunions occurred in the patients treated with plate fixation. There was significantly less disc space collapse and kyphotic deformity with the plated fusions than with the nonplated fusions, in which a pseudarthrosis developed. The complication rates for plated fusions are extremely low and do not differ from those for nonplated fusions.     

Persistent swallowing and voice problems after anterior cervical discectomy and fusion with allograft and plating: a 5- to 11-year follow-up study

Anterior cervical discectomy and fusion is commonly performed for cervical disc disease. Most studies report that swallowing and voice problems after such surgeries tend to resolve with time and are often of minor significance except in the rare cases of recurrent laryngeal nerve palsies. A retrospective review was performed on patients who had anterior cervical discectomy and fusion by a single surgeon more than 5 years prior, to determine the persistence of swallowing and voice problems in them.Seventy-four patients who had anterior cervical discectomy and fusion with allograft and plating an average of 7.2 years prior responded to an invitation to return for a follow-up clinical review. Emphasis was placed on the symptoms of dysphagia and dysphonia, as related to the index surgery. At final review, persistent dysphagia was present in 26 patients (35.1%). This occurred more frequently in females and in younger patients. Dysphonia at final review persisted in 14 patients (18.9%). This also occurred more commonly in females and in patients in whom possible non-union is present in at least one of the levels operated upon. Problems with singing were present in 16 patients (21.6%) postoperatively, occurring more frequently if the C3/4 disc was included in the surgery and in patients who have had a greater total number of anterior cervical surgeries at the time of review. Dysphonia and dysphagia are persistent problems in a significant proportion of patients, even beyond 5 years after anterior cervical spine surgery.The study was performed at the Columbia Spine Centre, Columbia, Missouri, USAPresented at the Cervical Spine Research Society (European Section) Annual Meeting, Porto, Portugal, 30 May to 5 June 2004     

Anterior discectomy and fusion for the management of neck pain

STUDY DESIGN: Data were collected prospectively on 38 patients who underwent anterior cervical discectomy and fusion for neck pain with no symptoms or signs of radiculopathy or myelopathy. OBJECTIVES: To determine the changes in pain and function after anterior cervical discectomy and fusion for nonradicular neck pain. SUMMARY OF BACKGROUND DATA: There is considerable controversy regarding the role of anterior cervical discectomy and fusion for neck pain in the absence of radiculopathy or myelopathy. Although no studies have addressed this specific and common problem, it is known that anterior cervical discectomy and fusion for radiculopathy or myelopathy may also provide relief of neck pain for many patients. METHODS: Thirty-eight patients who underwent anterior cervical discectomy and fusion for neck pain were evaluated. Before and after surgery, the authors measured pain with a numerical rating scale, function with the Oswestry Disability Questionnaire, and final patient satisfaction. Final evaluation was done by a disinterested third party. RESULTS: All 38 patients were available for follow-up study. Mean age was 42.4 years, and mean duration of follow-up study was 53 months. All patients had painful disc(s) proven by discography. No patients had nerve root compression. Anterior cervical discectomy and fusion was performed at one level in 21 patients, two levels in 16 patients, and three levels in one patient. The mean score on the numerical rating scale for neck pain before surgery was 8.3 (range, 3-10) versus 4.1 (range, 0-10) after surgery. This difference is significant (P < 0.001). The mean score on the Oswestry Disability Questionnaire was 57.5 (range, 0-89) before surgery versus 38.9 (range, 0-80) after surgery. This difference is significant (P < 0.001). There were 30 (79%) patients who were satisfied with their outcome, and 8 (21%) who were not satisfied. There was no statistical difference in change of pain or function between patients with worker's compensation and those with other insurance or between men and women. Twenty patients were not working because of neck pain before surgery, and 15 were not working at the time of follow-up examination. CONCLUSION: A significant decrease in pain, a significant increase in function, and a high degree of patient satisfaction were found with anterior cervical discectomy and fusion for neck pain. Improvements were not affected by worker's compensation status or gender.     

颈椎前路带锁与非带锁钢板螺钉系统固定强度的比较

目的：比较带锁与非带锁颈椎前路钢板螺钉系统的即刻固定和抗疲劳强度。方法：采用CSLP和Orion两种颈椎前路带锁钢板与Acroplate非带锁钢板固定于新鲜羊颈椎椎节,测定其即刻固定强度、抗疲劳强度和钢板螺钉的抗拉出力。结果：锁定状态的CSLP和Orion系统的即刻固定强度和抗疲劳强度均显著高于各自非锁定状态及Acroplate钢板单侧皮质螺钉固定。带锁钢板和相同螺钉长度的非带锁钢板的螺钉抗拉出力无明显差别。结论：锁定机制提高了颈椎前路钢板螺钉的即刻固定强度和抗疲劳强度。     

Cervical disc prosthesis in humans: first failure

STUDY DESIGN: Prospective preliminary trial of a cervical disc prosthesis. OBJECTIVE: To study the feasibility, efficacy in maintaining intervertebral mobility, and complications of a low-profile disc prosthesis implanted after single-level cervical discectomy. SUMMARY OF BACKGROUND DATA: Since studies reported by Baba et al, there is fear that degeneration of the intervertebral disc levels adjacent to cervical arthrodesis may be exacerbated by this arthrodesis. For this reason, several cervical prostheses have been designed as an alternative to arthrodesis. None of these prostheses, some of which are bulky, has been shown to be efficacious. METHODS: Five women and five men (average age, 36 years) underwent implantation of the present disc prosthesis after single-level discectomy. The discectomy was performed for cervical disc herniation that resulted in cervicobrachial pain for more than 3 months. None of the patients exhibited intervertebral instability on bending films. Preoperative magnetic resonance studies showed a noncontained disc herniation in all 10 patients and osteophytes in 2 of the patients. RESULTS: The cervicobrachial pain resolved in all 10 patients. Intense neck pain developed in 1 patient who underwent revision surgery to remove the prosthesis and perform an arthrodesis. Another patient developed neck pain but refused the proposed revision operation. Bending films showed mobility of the intervertebral space containing the prosthesis in both of these patients. In the 8 patients who remained pain free after the operation, lateral bending films at follow-up found no mobility of the implanted disc level. Five of these eight patients had circumferential fusion, 2 had posterior fusion, and 1 had anterior fusion. CONCLUSION: This prosthesis failed to achieve the desired effect because the intended mobility failed to persist in 8 of the 10 patients and pain developed in the other 2 patients, in whom the mobility persisted.     

Hardware failure in an unconstrained lumbar pedicle screw system. A 2-year follow-up study.

STUDY DESIGN: A consecutive study of patients who underwent lumbar spinal arthrodesis with an unconstrained pedicle screw system. OBJECTIVES: To determine the rate of arthrodesis and of clinical success and to examine and characterize the cases of hardware failure with the AO/Dynamic Compression Plate system (Synthes, Paoli, PA). SUMMARY OF BACKGROUND DATA: Although the advantages and disadvantages of nonconstrained versus constrained systems have been studied extensively, instrumentation failure has not. Additionally, the association between pseudarthrosis and hardware failure per se is unclear. METHODS: Seventy-four consecutive cases of lumbar spinal fusion are reviewed. Standard outcome scores based on pain relief and medication usage were tabulated, along with pertinent demographic data. The patients were observed at five intervals after surgery for at least 2 years (range, 24 to 35 months; mean, 27 months). Standard statistical analyses were used to analyze data. Status of the arthrodesis was determined by standard radiographic criteria. RESULTS: The overall fusion rate was 61%. At final follow-up, 60% of patients believed that their back pain had improved, whereas 70% believed that their limb pain had improved. The presence of a solid fusion (r = 3.3, P = 0.010) was correlated positively with a successful clinical outcome; the presence of pseudarthrosis and preoperative narcotic use were negatively correlated with a successful clinical outcome. Twenty-two percent of patients (16) experienced hardware failure. Twelve of the 16 had pseudarthrosis; in the majority of these patients, hardware failure occurred at the level of the pseudarthrosis. CONCLUSIONS: The results of this study demonstrate an extremely high rate of hardware failure and pseudarthrosis using an unconstrained pedicle screw system. Interestingly, the initial rate of pain relief was higher and declined over time and was quite possibly associated with loosening of the hardware. Based on these data, it is difficult to recommend the use of an unconstrained fixation system in the lumbar spine.     

Surgical outcome of single segment ventral fusion with plate osteosynthesis in therapy refractory chronic cervico-brachialgia

INTRODUCTION: In anterior cervical stabilization, collapses of the grafted bone with resulting localized kyphosis and graft dislocation has been reported. It was the aim of this clinical trial to evaluate the benefit of additional plating while taking specific implant-related complications into account. METHODS: The results of single level anterior cervical spinal fusion were evaluated. In 44 patients suffering from chronic cervical radicular pain with degenerative changes, arthrodesis with iliac-crest bone and plate fixation was performed. Apart from clinical parameters, the pre- and postoperative segmental kyphosis and cervical lordosis were evaluated. RESULTS: The total cervical alignment increased from 15.4 degrees to 18.5 degrees while the alignment of the fused segment increased from 2.6 degrees to 7.7 degrees. Postoperative decrease of correction did not occur. Bony fusion was confirmed in 95% after 12 months and 100% aller 36 months. Our results show that patients had more relief from radicular pain (80%) than from unspecific neck pain (66%). DISCUSSION: In single level anterior cervical fusion, additional plating successfully prevents dislocation of the bone graft and postoperative kyphosis. The clinical results and pseudarthrosis rate do not differ from studies without plating. Long. term follow-up studies are necessary to show the benefit of the reduced postoperative kyphosis.     

Cervical disc arthroplasty: Equivalent alternative to anterior cervical discectomy and fusion but unknown superiority

Cervical disc arthroplasty has been developed as an alternative to anterior cervical discectomy and fusion with the advantages of preserving intervertebral motion, eliminating the risk of pseudarthrosis, and theoretically reducing adjacent segment degeneration. Several large prospective randomized trials have been conducted to investigate the clinical and radiographic results of cervical disc arthroplasty versus anterior cervical discectomy and fusion. Long-term results from these studies, however, show no difference in functional outcomes and no evidence to date in reduction of adjacent segment disease with arthroplasty. Although cervical disc arthroplasty is a safe and equivalent alternative, its superiority is yet unknown.     

颈性眩晕外科治疗的指征及疗效探讨

目的探讨颈性眩晕外科治疗的指征及疗效。方法回顾分析2004年1月~2006年4月颈性眩晕患者100例,均经颈椎动力位及MRI检查。其中颈椎不稳21例:1个节段不稳5例,2个节段不稳10例,3个节段不稳6例;颈椎不稳主要发生于C4,5、C5,6节段;21例患者中MRI显示共43个不稳节段,其中32个节段合并颈椎间盘退变突出、硬膜囊出现压迹。本组21例患者均行颈前路椎间盘切除减压融合内固定术。结果21例均获随访,时间为12~39个月,术后12例眩晕获得缓解,5例有改善,4例眩晕改善不显著。手术治疗优良率为80%。结论颈椎不稳合并硬膜囊受压可以作为颈性眩晕的手术指征;采用颈前路椎间盘切除减压融合内固定治疗有较高的优良率。     

Three- and four-level anterior cervical discectomy and fusion with a PEEK cage and plate construct

Introduction

Three- or four-level anterior cervical discectomy and fusion with autograft and plate fixation have demonstrated relatively good fusion rates and outcomes, but donor site morbidity and the limitations of autograft harvest remain problematic. The purpose of this study is to assess the radiographic and clinical outcomes of three- or four-level anterior cervical discectomy and fusion with a PEEK cage and plate construct.

Methods

This retrospective review included 43 consecutive patients who underwent three- or four-level anterior cervical discectomy and fusion with a PEEK cage and plate construct (three level: 39 cases, four level: 4 cases). The fusion rate, time to fusion, Cobb angle and disc height were assessed radiographically. Clinical outcomes were evaluated with the VAS, NDI, and SF36 scores. Complications were also recorded.

Results

Solid fusion was achieved in all the patients, and mean time to fusion was 13.7 ± 5.1 weeks. The postoperative Cobb angle, lordotic angle, and disc height (5.6°, 10.5° and 3.15 mm, respectively) increased significantly compared to preoperative values (p = 0.038, p = 0.032, and p = 0.0004, respectively), and these improvements were maintained through final follow-up. The postoperative NDI (17.2), VAS (2.8), and SF36 (13.1) scores increased significantly compared to the preoperative scores (p = 0.026, p = 0.0007 and p = 0.041, respectively). Complications included three cases of respiratory difficulty, four cases of dysphagia and one case of hoarseness. There were no cases of donor site morbidity.

Conclusions

Three- or four-level anterior cervical discectomy and fusion with a PEEK cage, and plate construct provide good clinical and radiographic outcomes including high fusion rates, low complication rates, low donor site morbidity, and good maintenance of the lordotic angle and disc height in the treatment of multilevel cervical spondylosis.     

Long term outcome of anterior cervical discectomy and fusion using coral grafts

Background  To determine the long term efficacy of coral grafts in anterior cervical discectomy and fusion. Methods  In this prospective longitudinal study, All patients presenting with myelopathy and/or radiculopathy due to discal hernia or cervical spondylosis underwent anterior cervical microdiscectomy, arthrodesis with coral, and stabilization with anterior cervical locking plates. Clinical and radiological post-operative evaluations were performed at 2 days, 3, 6, and 12 months, and then yearly. The visual analogue scale was used for the evaluation of pain. Fusion was defined as the absence of motion on dynamic imaging combined with the disappearance of radio-lucent lines around the graft. The mean follow-up period was 44 months. In 83.3%, 91.2% and 93.7% of patients there was a satisfactory outcome for neck pain, arm pain, and motor deficit, respectively. The overall complication rate was 17.5%, all of which were transient. Additional surgery was required in nine cases. The occurrence of complications is correlated with less satisfactory outcomes for both neck and arm pain. While 95.5% of patients expressed overall satisfaction with their surgery, 70.5% stated that they had returned to their previous activities. The fusion rate was 45%; which was not correlated with clinical outcome and more likely in patients with of cervical spondylosis and one-level arthrodesis. Conclusions  Despite satisfactory clinical results and a long follow-up period, coral implants yield low fusion rates, particularly in patients with discal hernia of two-level arthrodesis. The use of coral grafts cannot be recommended when fusion is one of the post-operative endpoints. Sources of Support: None.     

Treatment of cervical pseudarthrosis after Smith-Robinson procedure with Halifax clamp fixation

Treatment of pseudarthrosis of the cervical spine has been debated extensively with various solutions being proposed. This article reviews 18 cases of pseudarthrosis after attempted anterior cervical discectomy and fusion with tricortical iliac crest autograft using the Smith-Robinson method. All cases were subsequently treated with posterior fusion using cancellous iliac autograft and fixation with Halifax clamps. All cases showed radiographic union at the 6-month follow-up. There were no complications related to the application of the device. One device showed loss of fixation in the follow-up period. The Halifax clamp is technically simple to apply and can be done safely. High success rates in obtaining fusion after failed anterior discectomy and fusion in the cervical spine and ease of application make this method of posterior fixation and fusion an attractive alternative for dealing with pseudarthrosis.     

颈椎前路融合术后假关节形成对疗效的影响

目的：观察颈椎前路减压融合术后假关节形成对神经功能和颈部症状的影响.方法：对109例颈椎前路减压融合术后患者进行平均11.1年的随访,常规拍摄颈椎屈伸侧位X线片,判断是否有假关节出现.采用JOA 17分法对手术前后的神经功能进行评定,观察术后患者的颈部症状并进行分级.对部分资料进行统计学分析.结果：109例患者的假关节发生率为26.61%（29/109）,单节段融合无假关节发生,而4节段融合的假关节发生率为36.36%.术后平均神经功能改善率为68.49%,颈部症状的发生率为35.78%.有假关节者与无假关节者比较,其神经功能改善率的差异有显著性意义（P＜0.05）,其颈部症状发生率相近.结论：假关节形成是颈椎前路手术后的常见远期并发症,其发生率与融合节段的多少有关.假关节形成可对术后远期神经功能恢复造成影响,但与患者术后颈部症状的发生无明显相关性.     

颈椎前路减压钢板内固定治疗外伤性颈椎间盘突出症

目的　探讨颈椎前路减压钢板内固定对于外伤性颈椎间盘突出症的疗效。方法　对 2 5例 2 0 0 0年 3月～2 0 0 2年 5月行颈椎前路减压钢板内固定治疗外伤性颈椎间盘突出症患者的临床资料及手术治疗结果进行回顾性分析。结果　 19例获随访的患者在 12～ 15周内均获得牢固骨融合 ,无骨不连发生。神经功能改善依据JOA评定标准 ,优 (改善率 >75 % ) 18例 ,良 (改善率 5 0 %～ 74 % ) 3例 ,中 (改善率 2 5 %～ 4 9% ) 2例 ,无效 (改善率 <2 5 % ) 2例。结论　颈椎前路开窗减压或椎体次全切除减压、植骨钢板内固定是治疗外伤性颈椎间盘突出症行之有效的方法     

前路钢板对两节段颈椎间植骨的运用价值

目的评价前路钢板对两节段颈椎间植骨融合的影响。方法46例两节段颈椎病患者,环锯法切除椎间盘、自体髂骨植骨,其中26例病人用了前路钢板内固定。术后复查X线片,了解植骨融合情况,并评价临床效果。结果26例运用钢板患者,全部获得骨性融合;20例单纯植骨病人,4例出现(20%)假关节,融合节段前凸丢失的度数较植骨融合组明显增大。获得植骨融合的病人,临床结果相似(P>0.05)。结论前路钢板系统增加两节段颈椎间植骨融合率、减少并发症。     

The effect of cervical plating on single-level anterior cervical discectomy and fusion

The use of anterior plates for single-level cervical fusions is controversial. Previous studies that evaluated single and multiple-level fusions have shown increased and decreased fusion rates when cervical plates are used. The purpose of this study was to compare the clinical and radiographic success of single-level discectomy performed with and without anterior cervical plate fixation. During a 6-year period, 80 patients were surgically treated with a single-level anterior cervical discectomy. Forty-four patients had cervical plates, whereas 36 had fusions without plates (average follow-up, 2.3 years). The pseudarthrosis rates were 4.5% (2 of 44) for patients with plating and 8.3% (3 of 36) without plating. This difference was not significant (p = 0.653). There was no correlation of pseudarthrosis with sex, age, level of surgery, history of tobacco use, or the presence of previous anterior surgery. The amount of graft collapse for patients with plating was 0.75 mm compared with 1.5 mm for those without a plate (p = 0.026). The amount of kyphotic deformity of the fused segment was 1.2 degrees with plating compared with 1.9 degrees for patients without plating (p = 0.079). Ninety-one percent of the patients with plating had good or excellent results compared with 88% in the group without cervical plates, based on Odom's criteria. The addition of plate fixation for single-level anterior cervical discectomy and fusion is safe and not associated with a significant increase in complication rates. The pseudarthrosis rates are not significantly different when a cervical plate is used.     

Anterior cervical diskectomy and fusion without plate instrumentation in 178 patients

Between 1989 and 1996, fusion, pseudarthrosis, repeated operation rates, and outcomes were studied in 178 patients undergoing one- to four-level (average, 2.2 levels) anterior cervical diskectomy and fusion (ADF) without plating. Dynamic radiographs taken 3 and 6 months after operation showed fusion or pseudarthrosis without motion in 99% of patients after one-level ADF (78 patients), in 90% after two-level ADF (84 patients), and in 100% after three-level ADF (12 patients) and four-level ADF (4 patients). Pseudarthrosis with motion was noted in 1% after one-level ADF and in 10% after two-level ADF (statistically significant with a lower pseudarthrosis rate in the 1-level; by Fisher's exact test, p = 0.0351). Three patients required secondary posterior wiring and fusion. Good or excellent outcomes (by Odom's criteria) were achieved in 96% of patients within an average of 82 months. Although fusion rates for one-level ADF without plates appear adequate, high pseudarthrosis rates after two-level ADF warrant that plating be considered.     

Comparison of single-level cervical fusion and a metal-on-metal cervical disc replacement device

Cervical fusion is the common treatment for cervical disc disease but can cause secondary disorders. The Prestige ST cervical disc prosthesis (Medtronic Sofamor Danek, Memphis, TN) was designed to preserve spinal motion to potentially limit the secondary disorders. In this article, we report 2-year results from a single-center study comparing use of this device with use of anterior cervical discectomy and fusion (ACDF). Nineteen patients were prospectively randomized to receive the device or to undergo ACDF. Twenty-four months after surgery, patients who received the device demonstrated improvement in neck pain, arm pain, and neurologic function. In our cohort, patients who underwent arthroplasty demonstrated greater improvement in neurologic function and neck pain than patients who underwent cervical discectomy and fusion.