A Comparison of Anterior Cervical Corpectomy and Fusion Combined With Artificial Disc Replacement and Cage Fusion in Patients With Multilevel Cervical Spondylotic Myelopathy

Management Considerations for Cervical Corpectomy: Updated Indications and Future Directions

Together, lower back and neck pain are among the leading causes of acquired disability worldwide and have experienced a marked increase over the past 25 years. Paralleled with the increasing aging population and the rise in chronic disease, this trend is only predicted to contribute to the growing global burden. In the context of cervical neck pain, this symptom is most often a manifestation of cervical degenerative disc disease (DDD). Traditionally, multilevel neck pain related to DDD that is recalcitrant to both physical and medical therapy can be treated with a procedure known as cervical corpectomy. Presently, there are many flavors of cervical corpectomy; however, the overarching goal is the removal of the pain-generating disc via the employment of the modern anterior approach. In this review, we will briefly detail the pathophysiological mechanism behind DDD, overview the development of the anterior approach, and discuss the current state of treatment options for said pathology. Furthermore, this review will also add to the current body of literature surrounding updated indications, surgical techniques, and patient outcomes related to cervical corpectomy. Finally, our discussion ends with highlighting the future direction of cervical corpectomy through the introduction of the "skip corpectomy" and distractable mesh cages.

Using Piezosurgery in Anterior Cervical Discectomy and Fusion to Treat Complex Cervical Spondylotic Myelopathy Is Safe and Effective

Objective

To investigate the safety and efficacy of piezosurgery in anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM).

Methods

47 patients with complex CSM (cCSM) underwent ACDF surgery from 2014 to 2017. Among these patients, 26 underwent ACDF using piezosurgery (group A) and 21 underwent ACDF by using traditional tools such as high-speed air drill, bone curette, and Kerrison bone punch (group B). Average surgical time, intraoperative blood loss, surgical complications, preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, and improvement rate were measured.

Results

Average surgical time and intraoperative blood loss were significantly lower in group A than those in group B (P < 0.01). The incidences of surgical complications were 3.8% and 23.8% in the A and B groups (P < 0.05), respectively. There were no significant differences in JOA scores and improvement rates between data collection periods at preoperative, 3-day postoperative, and 1-year postoperative follow-ups (P > 0.05).

Conclusion

For treating cCSM, both the piezosurgery and traditional tools led to significant neurological improvement. However, the piezosurgery was superior to the traditional tools in terms of surgical time, blood loss, and complication rate. Hence, piezosurgery was a safe and effective adjunct for ACDF treating cCSM.

Current and Expanded Indications for Cervical Disc Arthroplasty: Beyond the FDA IDE Studies

The widespread success of cervical disc arthroplasty (CDA) has led to an interest in expanding indications beyond those outlined in the initial Food and Drug Administration investigational device exemption studies. Some of these off-label indications currently include 3-level and 4-level CDA, hybrid constructs with adjacent segment anterior cervical discectomy and fusion or corpectomy constructs, pre-existing kyphosis, revision of a failed anterior cervical discectomy and fusion to a CDA, CDA in the setting of significant degenerative disc disease and/or facet joint arthropathy, CDA for congenital cervical stenosis, and CDA in the presence of ossification of the posterior longitudinal ligament. This review article will summarize the current literature pertaining to the aforementioned indications.

Current Evidence for Hybrid Constructs: Simultaneous ACDF/Arthroplasty and Arthroplasty Adjacent to Previous ACDF

It is not surprising that the utilization of hybrid constructs, combining cervical disc arthroplasty with anterior cervical disc arthroplasty, has steadily increased over the last decade. Known limitations exist with multi-level anterior cervical disc arthroplasty and cervical disc arthroplasty procedures. Hybrid surgery offers the possibility to address patient-specific pathology in a more tailored manner by restoring functional mobility and promoting fusion where appropriate. This review discusses the current evidence, both biomechanical and clinical, of hybrid surgery for 2-level and 3-level cervical disease.

Treatment of three-level cervical spondylotic myelopathy using ACDF or a combination of ACDF and ACCF

Objectives

This study aims to compare the outcomes between two anterior decompression and fusion techniques to treat multilevel cervical spondylotic myelopathy (MCSM).

Methods

After the screening for eligibility, a total of 66 patients were admitted to this study. These participants underwent anterior surgeries due to MCSM in our hospital between June 2016 and July 2018. All participants underwent either the anterior cervical discectomy and fusion (ACDF) surgery (ACDF group) or the combination of ACDF and anterior cervical corpectomy and fusion (ACCF), which was the anterior cervical hybrid decompression and fusion (ACHDF) surgery group. All the patients were followed up ≥18 months, the average latest followed up time was 23.64 (±2.69) months. The length of hospitalization, operation time, blood loss, visual analog scale (VAS), Japanese Orthopaedic Association (JOA) score, improvement rate, Hounsfield units (HU) of C3–C7, cobb angle, and anterior column height of fusion levels pre and post operation were analyzed.

Results

There were no statistical differences between the ACDF and ACHDF groups regarding the length of hospitalization, operation time, blood loss, HU of C3–C7, VAS, JOA score, improvement rate, cobb angle, and anterior column height in fusion levels in pre-operation and 3 months after operation (all P > 0.05). However, compared with the ACHDF group, the ACDF group achieved significantly better improvement in the anterior column height of fusion levels in the final 18–29 months post-operatively (P < 0.05).

Conclusions

Both approaches of ACDF alone and a combination of ACDF and ACCF can achieve satisfactory outcomes in the treatment of MCSM, but ACDF has better outcomes in maintaining anterior column height of fusion levels.

Open-Door versus French-Door Laminoplasty for Patients with Multisegmental Cervical Spondylotic Myelopathy: A Systematic Review and Meta-analysis

This study aimed to evaluate the superiority of open-door versus French-door posterior cervical laminoplasty in the treatment of multisegmental cervical spondylotic myelopathy by comparing the intraoperative parameters and clinical and radiologic outcomes of these 2 procedures. PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, the Wanfang database, the Weipu database, and China Biology Medicine disk were searched. Articles were retrieved from database establishment through May 22, 2020. Data analysis was carried out on the retrieved articles using RevMan 5.3 software. This meta-analysis included 14 studies involving 1010 patients, among which 6 were randomized controlled trials and 8 were retrospective analyses. Comparing the open-door and French-door groups, no statistically significant differences were found in operative time (weighted mean difference [WMD] = -4.47, 95% CI [-17.85, 8.92], P = 0.51), postoperative Japanese Orthopaedic Association score (WMD= -0.24, 95% CI [-0.87, 0.38], P = 0.45), recovery rate (WMD= -0.58, 95% CI [-3.61, 2.45], P = 0.71), postoperative cervical lordosis (WMD= -0.15, 95% CI [-1.93, 1.63], P = 0.87), cervical range of motion (WMD = -3.04, 95% CI [-8.68, 2.59], P = 0.29), sagittal diameter of the spinal canal (WMD = -0.24, 95% CI [-0.54, 0.07], P = 0.13), incidence of C5 palsy (OR = 1.78, 95% CI [0.64, 4.93], P = 0.27), or incidence of cerebrospinal fluid leakage (OR = 1.51, 95% CI [0.48, 4.71], P = 0.48). However, the French-door group was associated with less intraoperative bleeding (WMD = 54.96, 95% CI [21.37, 88.55], P = 0.001) and a lower incidence of axial symptoms (OR = 2.50, 95% CI [1.32, 4.72], P = 0.005). This analysis suggests that both methods can achieve good postoperative outcomes. However, less intraoperative bleeding and a lower incidence of postoperative axial symptoms were found in the French-door group. This requires further validation and investigation in larger sample-size and well-designed randomized controlled studies.

Determining the Difference in Clinical and Radiologic Outcomes Between Expandable and Nonexpandable Titanium Cages in Cervical Fusion Procedures: A Systematic Review and Meta-Analysis

BACKGROUND

Expandable cages have been increasingly used in cervical and lumbar reconstructions; however, there is a paucity in the literature on how they compare with traditional nonexpandable cages in the cervical spine. We present a systematic review and meta-analysis, comparing the clinical and radiologic outcomes of expandable versus nonexpandable corpectomy cage use in the cervical spine.

METHODS

A database search identified studies detailing the outcomes of expandable and nonexpandable titanium cage use in the cervical spine. These studies were screened using the PRISMA protocol. Fixed-effects and random-effects models were used with a 95% confidence interval. Two analyses were carried out for each outcome: one including all studies and the other including only studies reporting on exclusively 1-level and 2-level cases.

RESULTS

Forty-one studies were included. The mean change in segmental lordosis was significantly greater in expandable cages (all, 6.72 vs. 3.69°, P < 0.001; 1-level and 2-level, 6.81° vs. 4.31°, P < 0.001). The mean change in cervical lordosis was also significantly greater in expandable cages (all, 5.71° vs. 3.11°, P = 0.027; 1-level and 2-level, 5.71° vs. 2.07°, P = 0.002). No significant difference was found between the complication rates (all, P = 0.43; 1-level and 2-level, P = 0.94); however, the proportion of revisions was significantly greater in expandable cages (all, 0.06 vs. 0.02, P = 0.03; 1-level and 2-level, 0.08 vs. 0.01, P = 0.017).

CONCLUSIONS

The use of expandable cages may carry a modest improvement in radiologic outcomes compared with nonexpandable cages in the cervical spine; however, they may also lead to a higher rate of revisions based on our analyses.

Does Hybrid Surgery Improve Quality of Life in Multilevel Cervical Degenerative Disk Disease? Five-Year Follow-up Study

BACKGROUND

Patient satisfaction is becoming an increasing factor worthy of consideration when evaluating the surgical quality. The correlation between patient satisfaction and surgical outcomes 5 years after cervical hybrid surgery (HS), which incorporates anterior cervical decompression and fusion and cervical disk arthroplasty techniques in multilevel cervical degenerative disk disease, has not been evaluated.

METHODS

The aim of this study was firstly to analyze prospectively collected data from a sample of patients (n = 50) treated with cervical HS for selected cases of radiculopathy and myelopathy in order to evaluate pain levels of patients, using the Neck and Arm Pain scale as an expression of visual analog scale. Secondly, we aimed to evaluate health-related quality of life, via the short-form 36, Neck Disability Index, and Japanese Orthopedic Association score. Patients were followed up for more than 5 years. Intraoperative parameters, clinical features, and outcome scores were recorded. Radiologic investigations including disk height and changes in adjacent disk spaces were assessed.

RESULTS

Clinical improvements were observed in all outcomes; significant improvements on the Neck Disability Index, visual analog scale, short-form 36, and Japanese Orthopedic Association scores were maintained at 5 years (P < 0.05). The mean disk height resulted restored in all the cases. Temporary dysphagia was rarely observed (3%). No surgery for adjacent-level disease was required. There was no significant difference in the outcomes between radiculopathy and myelopathy groups (P > 0.05).

CONCLUSIONS

HS is an effective and safe procedure for the treatment of multilevel cervical degenerative disk disease. Such a surgical construct offers postoperative improvement on pain levels and health-related quality of life.

Hybrid decompression and reconstruction technique for cervical spondylotic myelopathy: case series and review of the literature

The primary treatment of choice for patients with cervical spondylotic myelopathy (CSM) is surgical decompression. The benefit of operative intervention has been well established but, the surgeons' decision of operative approach remains nuanced based on patient-specific variables and surgeon preference. Decompression can involve a cervical corpectomy or a discectomy. A hybrid construct is when both a cervical corpectomy and a discectomy are done in the same patient. The purpose of this study was to review the evidence on the clinical and biomechanical outcomes of hybrid decompression and reconstruction techniques in patients with multilevel CSM. A retrospective study was performed on consecutive patients who received hybrid anterior decompression and reconstruction at Rush University between 2013-2018. Preoperative clinical and radiographic variables were analyzed to characterize specific factors leading to the decision of the surgical approach. In addition, we performed a systematic review and meta-analysis to assess superiority in terms of operative time, blood loss, cervical lordosis, patient-reported outcomes (PRO), fusion rates, and complications. Hybrid surgery (HS) was utilized in cases where multilevel CSM was present in conjunction with stenosis posterior to the vertebral body or acute kyphotic deformity. Our meta-analysis highlighted comparable PRO, complications, and rate of success fusion between 3-level anterior cervical discectomy and fusion (ACDF) and hybrid technique. Furthermore, hybrid fusion led to increased postoperative cervical lordosis, higher fusion rate, lower total complication rate, lower implant failure/mesh subsidence rate, and lower blood loss than 2-level corpectomy. The cervical hybrid technique that combines cervical corpectomy and discectomy represents a balanced option with the benefits of two commonly utilized cervical spine procedures in patients with multilevel CSM. The literature on hybrid technique suggests in cases where multilevel ACDF is not feasible, combining discectomy and corpectomy is superior to two-level corpectomy with lower complication rates, improved clinical outcome, spinal alignment correction, and stronger biomechanical properties.

Comprehensive Analysis of Hybrid Surgery and Anterior Cervical Discectomy and Fusion in Cervical Diseases: A Meta-Analysis

To investigate the outcomes and reliability of hybrid surgery (HS) versus anterior cervical discectomy and fusion (ACDF) for the treatment of multilevel cervical spondylosis and disc diseases.Hybrid surgery, combining cervical disc arthroplasty (CDA) with fusion, is a novel treatment to multilevel cervical degenerated disc disease in recent years. However, the effect and reliability of HS are still unclear compared with ACDF.To investigate the studies of HS versus ACDF in patients with multilevel cervical disease, electronic databases (Medline, Embase, Pubmed, Cochrane library, and Cochrane Central Register of Controlled Trials) were searched. Studies were included when they compared HS with ACDF and reported at least one of the following outcomes: functionality, neck pain, arm pain, cervical range of motion (ROM), quality of life, and incidence of complications. No language restrictions were used. Two authors independently assessed the methodological quality of included studies and extracted the relevant data.Seven clinical controlled trials were included in this study. Two trials were prospective and the other 5 were retrospective. The results of the meta-analysis indicated that HS achieved better recovery of NDI score (P = 0.038) and similar recovery of VAS score (P = 0.058) compared with ACDF at 2 years follow-up. Moreover, the total cervical ROM (C2-C7) after HS was preserved significantly more than the cervical ROM after ACDF (P = 0.000) at 2 years follow-up. Notably, the compensatory increase of the ROM of superior and inferior adjacent segments was significant in ACDF groups at 2-year follow-up (P < 0.01), compared with HS.The results demonstrate that HS provides equivalent outcomes and functional recovery for cervical disc diseases, and significantly better preservation of cervical ROM compared with ACDF in 2-year follow-up. This suggests the HS is an effective alternative invention for the treatment of multilevel cervical spondylosis to preserve cervical ROM and reduce the risk of adjacent disc degeneration. Nonetheless, more well-designed studies with large groups of patients are required to provide further evidence for the benefit and reliability of HS for the treatment of cervical disk diseases.

Clinical and Radiographic Outcome of Patients With Cervical Spondylotic Myelopathy Undergoing Total Disc Replacement

STUDY DESIGN

A nonrandomized, prospective, and single-center clinical trial.

OBJECTIVE

The aim of this study was to investigate the clinical and radiographic efficacy of ProDisc Vivo cervical total disc replacement (cTDR) in patients with clinical and radiographic documented cervical spondylotic myelopathy (CSM), due to degenerative changes at the index level.

SUMMARY OF BACKGROUND DATA

Decompression and fusion is still the gold standard in patients with cervical myelopathy. Very limited data are available regarding the application of cTDR in patients with clinical and radiological documented CSM in context of clinical and radiographic outcomes.

METHODS

Clinical outcome scores included the Neck Disability Index (NDI), Visual Analogue Scale (VAS), arm and neck pain self-assessment questionnaires as well as the Nurick grade and the Japanese Orthopaedic Association (JOA) score. The radiological outcome included the range of motion (ROM), the segmental and global (C2-C7) lordosis, and the occurrence of heterotopic ossifications.

RESULTS

Eighteen consecutive patients (10 males, 8 females) with documented clinical and radiological signs of myelopathy were included in this investigation. The study population had a mean age of 52.4 years and a follow-up period of 20.3 months in average (range 3-48 months). The mean range ROM of the index level stayed consistent with 6.8° preoperatively and 7.2° (P = 0.578) at the last follow-up; the global lordosis in neutral position changed from 3.5° to 14.2° significantly (P = 0.005) in mean. The JOA score improved from 11.3 to 16.6 (P < 0.001) as well as the NDI 36.7 to 10.3 (P < 0.001) and the VAS score from 5.7/6.1 (arm/neck) to 1.3/2.0 (P < 0.001/P < 0.001). The mean Nurick grade was 1.33 preoperatively and dropped down in all cases to Nurick grade of 0 (P < 0.001).

CONCLUSION

cTDR (with ProDisc Vivio) in patients with CSM yielded good clinical and radiographic outcomes and found as a reliable, safe, and motion-preserving surgical treatment option, although its indication is very limited due to numerous exclusion criteria.

LEVEL OF EVIDENCE

4.

Anterior cervical discectomy and fusion versus hybrid surgery in multilevel cervical spondylotic myelopathy: A meta-analysis

OBJECTIVE

A meta-analysis was performed to compare the radiographic and surgical outcomes between anterior cervical discectomy and fusion (ACDF) and hybrid surgery (HS, corpectomy combined with discectomy) in the treatment for multilevel cervical spondylotic myelopathy (mCSM).

SUMMARY OF BACKGROUND DATA

Both ACDF and HS are used to treat mCSM, however, which one is better treatment for mCSM remains considerable controversy.

METHODS

An extensive search of literature was searched in PubMed/Medline, Embase, the Cochrane library, CNKI, and WANFANG databases on ACDF versus HS treating mCSM from January 2011 to December 2017. The following variables were extracted: blood loss, operation time, fusion rate, Cobb angles of C2-C7, total complications, dysphagia, hoarseness, C5 palsy, infection, cerebral fluid leakage, epidural hematoma, and graft subsidence. Data analysis was conducted with RevMan 5.3 and STATA 12.0.

RESULTS

A total of 4 studies including 669 patients were included in our study. The pooled analysis showed that there were no significant difference in the operation time, fusion rate, Cobb angles of C2-C7, dysphagia, hoarseness, C5 palsy, infection, cerebral fluid leakage, epidural hematoma, and graft subsidence. However, there were significant difference between 2 groups in blood loss [P < .00001, SMD = -30.29 (-45.06, -15.52); heterogeneity: P = .38, I = 0%= and total complications [P = .04, OR = 0.66 95%CI (0.44, 0.98); heterogeneity: P = .37, I = 4%].

CONCLUSIONS

Based on our meta-analysis, except for blood loss and total complications, both ACDF and hybrid surgery are effective options for the treatment of multilevel cervical spondylotic myelopathy.

Incidence and clinical relevance of cage subsidence in anterior cervical discectomy and fusion: a systematic review

Background

The placement of intervertebral cages in anterior cervical discectomy (ACDF) supposedly maintains foraminal height. The most commonly reported cage-related complication is subsidence, although it is unknown whether a correlation between subsidence and clinical outcome exists.

Aim

To assess the incidence and relevance of subsidence.

Methods

Literature searches were performed in PubMed, MEDLINE, Embase, Web of Science, COCHRANE, and CENTRAL. The inclusion criteria were as follows: ≥ 20 patients, ADCF with cage, subsidence assessed, and primary data. Risk of bias was assessed using adjusted Cochrane checklists.

Results

Seventy-one studies, comprising 4784 patients, were included. Subsidence was generally defined as ≥ 3-mm loss of height comparing postoperative intervertebral heights with heights at last follow-up. Mean incidence of subsidence was 21% (range 0–83%). Of all patients, 46% of patients received polyether-ether-ketone (PEEK) cages, 31% received titanium cages, 18% received cage-screw-combinations, and 5% received polymethyl-methacrylate (PMMA) cages. Patients treated with cage-screw-combinations had significantly less subsidence than patients treated with PEEK, titanium, or PMMA cages (15.1% vs. 23.5% vs. 24.9% vs. 30.2%; p < 0.001). Thirteen studies assessed clinical outcome in relation to subsidence; the majority did not find a significant correlation. Only four studies correlated subsidence to cage size and/or height; no correlation was established.

Conclusions

Subsidence in ACDF with cages occurs in 21% of patients. The risk for subsidence seems lower using PEEK or titanium cages or adding screws. Whether subsidence affects clinical outcome is not satisfactorily evaluated in the available literature. Future studies on this correlation are warranted in order to establish the additional value of the interposition of a cage in ACDF.

Cervical disc arthroplasty with Prestige-LP for the treatment of contiguous 2-level cervical degenerative disc disease: 5-year follow-up results

The objective of this study is to present the long-term results and to evaluate the safety and effectiveness of the Prestige-LP cervical disc replacement in treatment of patients with symptomatic 2-level cervical degenerative disc disease.Twenty-four patients with 48 Prestige-LP disc were analyzed before surgery and at 1 week, 3 months, 6 months, 12 months, 24 months, and 60 months after surgery. Clinical assessments included 36-Short Form (SF-36), Japanese Orthopedic Assessment (JOA), visual analog scale (VAS), and Neck Disability Index (NDI) scores. Radiographic assessments included cervical lordosis (CL), disc height (DH), range of motion (ROM) of the total cervical spine, functional spinal unit (FSU) as well as upper and lower operated segment. Complications at the 5-year follow-up were collected as well.Mean follow-up period was 64.22 months. There was clinical improvement in terms of SF-36, JOA, NDI, and VAS from the preoperative to the final follow-up (P < .05). Overall, ROM of the total cervical spine, FSU, and upper and lower operated segment were maintained during the follow-up. Statistically significant (P < .05) improvements in the trend of CL and DH were noted at the follow-up. Eight patients were observed an appearance of heterotopic ossification at the 5-year follow-up, with 6 patients appeared at Class II and 2 patients at Class III. Adjacent segment degeneration assessed by radiographic evidence was found in 2 patients.Two-level cervical disc arthroplasty with Prestige-LP showed significant improvement in clinical outcomes at 5 years. It not only effectively preserves the motion of both total cervical spine and operated segments, but also restores normal CL and DH up to 5 years postoperation.

Reliability and validity of CODA motion analysis system for measuring cervical range of motion in patients with cervical spondylosis and anterior cervical fusion

The aim of the present study was to evaluate the reliability of the Cartesian Optoelectronic Dynamic Anthropometer (CODA) motion system in measuring the cervical range of motion (ROM) and verify the construct validity of the CODA motion system. A total of 26 patients with cervical spondylosis and 22 patients with anterior cervical fusion were enrolled and the CODA motion analysis system was used to measure the three-dimensional cervical ROM. Intra- and inter-rater reliability was assessed by interclass correlation coefficients (ICCs), standard error of measurement (SEm), Limits of Agreements (LOA) and minimal detectable change (MDC). Independent samples t-tests were performed to examine the differences of cervical ROM between cervical spondylosis and anterior cervical fusion patients. The results revealed that in the cervical spondylosis group, the reliability was almost perfect (intra-rater reliability: ICC, 0.87–0.95; LOA, −12.86–13.70; SEm, 2.97–4.58; inter-rater reliability: ICC, 0.84–0.95; LOA, −13.09–13.48; SEm, 3.13–4.32). In the anterior cervical fusion group, the reliability was high (intra-rater reliability: ICC, 0.88–0.97; LOA, −10.65–11.08; SEm, 2.10–3.77; inter-rater reliability: ICC, 0.86–0.96; LOA, −10.91–13.66; SEm, 2.20–4.45). The cervical ROM in the cervical spondylosis group was significantly higher than that in the anterior cervical fusion group in all directions except for left rotation. In conclusion, the CODA motion analysis system is highly reliable in measuring cervical ROM and the construct validity was verified, as the system was sufficiently sensitive to distinguish between the cervical spondylosis and anterior cervical fusion groups based on their ROM.

A comparison of anterior cervical discectomy and fusion combined with cervical disc arthroplasty and cervical disc arthroplasty for the treatment of skip-level cervical degenerative disc disease: A retrospective study

Anterior cervical discectomy and fusion (ACDF) has been widely performed for the treatment of multilevel cervical degenerative disc disease (CDDD). In recent decades, cervical disc arthroplasty (CDA) and hybrid surgery (HS) have been developed to overcome the shortcomings of ACDF. Controversy still remains with regard to the optimal surgical procedure for skip-level CDDD.A total of 55 patients who received surgical treatment for skip-level CDDD in our department were reviewed. The patients were divided into the HS group (n = 29) and the CDA group (n = 26). The collected data included Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), and Visual Analog Scale (VAS) scores, and cervical lordosis (CL), range of motion (ROM), and intervertebral disc height (IDH). Radiological changes at the intermediate segment (IS) were also collected. All data were collected preoperatively and at routine postoperative intervals of 1 week and 3, 6, and 12 months and at the last follow-up period.Compared with preoperative values, mean JOA, NDI, and VAS scores significantly improved after surgery in both the HS and CDA groups (P < .05). However, there were no significant differences between the groups (P > .05). The HS group had better CL recovery than the CDA group after surgery (P < .05). There was no significant difference in the ROM of C2-C7 between the 2 groups (P > .05). A significant difference in the ROM of the IS was found at the last follow-up between the 2 groups (P < .05). At the last-follow-up, 4 discs (14.29%) in the CDA group and 6 discs (19.36%) in the HS group had adjacent segment degeneration (ASD) without symptoms.Both HS and CDA might be considered safe and effective surgical strategies for the treatment of skip-level CDDD. Although the clinical outcomes were similar in the 2 groups, CDA altered the ROM of the IS to a lesser degree.

A Comparison of the Anterior Approach and the Posterior Approach in Treating Multilevel Cervical Myelopathy: A Meta-Analysis

STUDY DESIGN

A meta-analysis.

OBJECTIVE

To compare the effectiveness and the safety of the anterior approach with those of the posterior approach for patients diagnosed with multilevel cervical myelopathy (MCM).

SUMMARY OF BACKGROUND DATA

Although many studies had compared the outcomes of the anterior approach with that of the posterior approach for MCM in recent years, choosing a proper surgical approach is still a controversial issue .

METHODS

We searched electronic databases for relevant studies that compared the anterior approach with the posterior approach for MCM. Then, data extraction and quality assessment were conducted. We used RevMan 5.3 for data analysis. A random effects model was used for heterogenous data, whereas a fixed-effects model was used for homogenous data.

RESULTS

A total of 25 nonrandomized controlled studies involving 1843 patients were included. No statistical difference was found with regard to the preoperative Japanese Orthopedic Association (JOA) score between the anterior group and the posterior group (P=0.08, 95% CI, -0.02 to 0.40). The postoperative JOA score and the recovery rate were higher in the anterior group as compared with the posterior group (P=0.02, 95% CI, 0.10-1.33; P=0.006, 95% CI, 2.33-13.90). In the subgroup analysis, better postoperative JOA scores and recovery rates were also obtained in the anterior group for cervical spondylotic myelopathy (P=0.0007, 95% CI, 0.29-1.09; P=0.01, 95% CI, 1.30-9.93). No significant differences were found in the complication rate, the revision rate, the operation time, and blood loss between the 2 groups (P=0.17, 95% CI, 0.89-1.95; P=0.21, 95% CI, 0.72-4.61; P=0.31, 95% CI, -20.20 to 63.30; P=0.88, 95% CI, -166.86 to 143.81).

CONCLUSIONS

The anterior approach is associated with a better postoperative neurological outcome compared with the posterior approach in cervical spondylotic myelopathy patients. Considering the complication rate, the revision rate, the operation time, and blood loss, the anterior approach appears to be as safe as the posterior approach. Further randomized controlled trials comparing the anterior approach and the posterior approach for MCM should be performed to make a more convincing conclusion.

Anterior cervical discectomy and fusion versus anterior cervical corpectomy and fusion in multilevel cervical spondylotic myelopathy: A meta-analysis

BACKGROUND

Both anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) are used to treat multilevel cervical spondylotic myelopathy (mCSM); however, which one is better treatment for mCSM remains considerable controversy. A meta-analysis was performed to compare clinical outcomes, radiographic outcomes, and surgical outcomes between ACDF and ACCF in treatment for mCSM.

METHODS

An extensive search of literature was performed in Pubmed/MEDLINE, Embase, the Cochrane library, CNKI, and WANFANG databases on ACDF versus ACCF treatment for mCSM from January 2011 to August 2016. The following variables were extracted: length of hospital stay, blood loss, operation time, Japanese Orthopedic Association (JOA) scores, Neck Disability Index (NDI) score, fusion rate, Cobb angles of C2 to C7, dysphagia, hoarseness, C5 palsy, infection, cerebral fluid leakage, donor site pain, epidural hematoma, graft subsidence, graft dislodgment, pseudoarthrosis, and total complications. Data analysis was conducted with RevMan 5.3 and STATA 12.0.

RESULTS

A total of 8 studies containing 878 patients were included in our study. The results showed that ACDF is better than ACCF in the angle of C2 to C7 at the final follow-up (P < 0.00001, standardized mean difference = 4.76 [3.48, 6.03]; heterogeneity: P = 0.17, I = 43%), C5 plasy (P = 0.02, odds ratio [OR] 0.42, 95% confidence interval [CI] 0.21, 0.86; heterogeneity: P = 0.52, I = 0%), blood loss (P < 0.00001, standardized mean difference = -53.12, 95% CI -64.61, -41.64; heterogeneity: P = 0.29, I = 20%), fusion rate (P = 0.04, OR 2.54, 95% CI 1.05, 6.11; heterogeneity: P = 0.29, I = 20%), graft subsidence (P = 0.004, OR 0.11, 95% CI 0.02, 0.48; heterogeneity: P = 0.94, I = 0%), and total complications (P = 0.0009, OR 0.56, 95% CI 0.40, 0.79; heterogeneity: P = 0.29, I = 18%).However, there are no significant differences in length of hospital stay, operation time, JOA scores, NDI scores, preoperative angle of C2 to C7, dysphagia, hoarseness, infection, cerebral fluid leakage, donor site pain, epidural hematoma, graft dislodgment, and pseudoarthrosis (all P > 0.05).

CONCLUSIONS

Based on our meta-analysis, our results suggest that both ACDF and ACCF are good plans in clinical outcomes; however, ACDF is a better choice in radiographic outcomes and total complications for the treatment of multilevel CSM.

Treating multi-level cervical disc disease with hybrid surgery compared to anterior cervical discectomy and fusion: a systematic review and meta-analysis

PURPOSE

The traditional surgical approach to treat multi-level cervical disc disease (mCDD) has been anterior cervical discectomy and fusion (ACDF). There has been recent development of other surgical approaches to further improve clinical outcomes. Collectively, when elements of these different approaches are combined in surgery, it is known as hybrid surgery (HS) which remains a novel treatment option. A systematic review and meta-analysis was conducted to compare the outcomes of HS versus ACDF for the treatment of mCDD.

METHODS

Relevant articles were identified from six electronic databases from their inception to January 2016.

RESULTS

From 8 relevant studies identified, 169 patients undergoing HS were compared with 193 ACDF procedures. Operative time was greater after HS by 42 min (p < 0.00001), with less intraoperative blood loss by 26 mL (p < 0.00001) and shorter return to work by 32 days (p < 0.00001). In terms of clinical outcomes, HS was associated with greater C2-C7 range of motion (ROM) preservation (p < 0.00001) and less functional impairment (p = 0.008) after surgery compared to ACDF. There was no significant difference between HS and ACDF with respect to postoperative pain (p = 0.12). The postoperative course following HS was not significantly different to ACDF in terms of length of stay (p = 0.24) and postoperative complication rates (p = 0.18).

CONCLUSIONS

HS is a novel surgical approach to treat mCDD, associated with a greater operative time, less intraoperative blood loss and comparable if not superior clinical outcomes compared to ACDF. While it remains a viable consideration, there is a lack of robust clinical evidence in the literature. Future large prospective registries and randomised trials are warranted to validate the findings of this study.

Comparison of Cervical Kinematics, Pain, and Functional Disability Between Single- and Two-level Anterior Cervical Discectomy and Fusion

STUDY DESIGN

A prospective, time series design.

OBJECTIVE

The purpose of this study is two-fold: firstly, to investigate the impact of altered cervical alignment and range of motion (ROM) on patients' self-reported outcomes after anterior cervical discectomy and fusion (ACDF), and secondly, to comparatively differentiate the influence of single- and two-level ACDF on the cervical ROM and adjacent segmental kinematics up to 12-month postoperatively.

SUMMARY OF BACKGROUND DATA

ACDF is one of the most commonly employed surgical interventions to treat degenerative disc disease. However, there are limited in vivo data on the impact of ACDF on the cervical kinematics and its association with patient-reported clinical outcomes.

METHODS

Sixty-two patients (36 males; 55.63 ± 11.6 yrs) undergoing either a single- or consecutive two-level ACDF were recruited. The clinical outcomes were assessed with the Pain Visual Analogue Scale (VAS) and the Neck Disability Index (NDI). Radiological results included cervical lordosis, global C2-C7 ROM, ROM of the Functional Spinal Unit (FSU), and its adjacent segments. The outcome measures were collected preoperatively and then at 3, 6, and 12-month postoperatively.

RESULTS

A significant reduction of both VAS and NDI was found for both groups from the preoperative to 3-month period (P < 0.01). Pearson correlation revealed no significant correlation between global ROM with neither VAS (P = 0.667) nor NDI (P = 0.531). A significant reduction of global ROM was identified for the two-level ACDF group at 12 months (P = 0.017) but not for the single-level group. A significant interaction effect was identified for the upper adjacent segment ROM (P = 0.024) but not at the lower adjacent segment.

CONCLUSION

Current study utilized dynamic radiographs to comparatively evaluate the biomechanical impact of single- and two-level ACDF. The results highlighted that the two-level group demonstrated a greater reduction of global ROM coupled with an increased upper adjacent segmental compensatory motions that is independent of patient-perceived recovery.

LEVEL OF EVIDENCE

3.

Hybrid Surgery Versus Anterior Cervical Discectomy and Fusion in Multilevel Cervical Disc Diseases: A Meta-Analysis

To investigate the outcomes and reliability of hybrid surgery (HS) versus anterior cervical discectomy and fusion (ACDF) for the treatment of multilevel cervical spondylosis and disc diseases.Hybrid surgery, combining cervical disc arthroplasty (CDA) with fusion, is a novel treatment to multilevel cervical degenerated disc disease in recent years. However, the effect and reliability of HS are still unclear compared with ACDF.To investigate the studies of HS versus ACDF in patients with multilevel cervical disease, electronic databases (Medline, Embase, Pubmed, Cochrane library, and Cochrane Central Register of Controlled Trials) were searched. Studies were included when they compared HS with ACDF and reported at least one of the following outcomes: functionality, neck pain, arm pain, cervical range of motion (ROM), quality of life, and incidence of complications. No language restrictions were used. Two authors independently assessed the methodological quality of included studies and extracted the relevant data.Seven clinical controlled trials were included in this study. Two trials were prospective and the other 5 were retrospective. The results of the meta-analysis indicated that HS achieved better recovery of NDI score (P = 0.038) and similar recovery of VAS score (P = 0.058) compared with ACDF at 2 years follow-up. Moreover, the total cervical ROM (C2-C7) after HS was preserved significantly more than the cervical ROM after ACDF (P = 0.000) at 2 years follow-up. Notably, the compensatory increase of the ROM of superior and inferior adjacent segments was significant in ACDF groups at 2-year follow-up (P < 0.01), compared with HS.The results demonstrate that HS provides equivalent outcomes and functional recovery for cervical disc diseases, and significantly better preservation of cervical ROM compared with ACDF in 2-year follow-up. This suggests the HS is an effective alternative invention for the treatment of multilevel cervical spondylosis to preserve cervical ROM and reduce the risk of adjacent disc degeneration. Nonetheless, more well-designed studies with large groups of patients are required to provide further evidence for the benefit and reliability of HS for the treatment of cervical disk diseases.