Anterior Cervical Discectomy and Fusion with Zero-Profile Anchored Spacer Versus Plate and Cage for 3-Level Contiguous Cervical Degenerative Disease: A Systematic Review and Meta-Analysis.

OBJECTIVE: To compare the safety, clinical outcomes, and radiological results of anterior cervical discectomy and fusion (ACDF) with zero-profile anchored spacer (ZPAS) versus plate and cage (PC) for 3-level contiguous cervical degenerative disease. METHODS: The study was registered at PROSPERO (CRD42024512706). The Web of Science core collection, PubMed, and Embase were searched up to February 12, 2024. Review Manager 5.3 was used. The relative risk (RR) and 95% confidence interval were evaluated for dichotomous data. Continuous data were assessed using the mean difference and 95% confidence interval. RESULTS: Nine studies comparing ACDF with ZPAS versus PC for 3-level contiguous cervical degenerative disease were included. The intraoperative blood loss and operation time in ZPAS were significantly less than those in PC. The subsidence rate, loss of cervical alignment, fusion segmental height, and intervertebral disc height were significantly greater in ZPAS than in PC. The cervical alignment and dysphagia rate within 6 months were significantly lower in ZPAS than in PC. The ASD of ZPAS was significantly lower than that of PC according to the sensitivity analysis when 1 study was excluded. No significant differences were identified in the other aspects. CONCLUSIONS: Both ACDF with ZPAS and PC were safe and effective procedures. PC was associated with increased surgical trauma. The ZPAS could better decrease the incidence of ASD and dysphagia. ZPAS was also accompanied by high subsidence rate and poor cervical alignment.

Segment selection for fusion and artificial disc replacement in the hybrid surgical treatment of noncontiguous cervical spondylosis: a finite element analysis.

Introduction: The treatment of skip-level cervical degenerative disease (CDD) with no degenerative changes observed in the intervening segment (IS) is complicated. This research aims to provide a reference basis for selecting treatment approaches for noncontiguous CDD. Methods: To establish accurate finite element models (FEMs), this study included computed tomography (CT) data from 21 patients with CDD (10 males and 11 females) for modeling. The study primarily discusses four cross-segment surgical approaches: upper (C3/4) anterior cervical discectomy and fusion (ACDF) and lower (C5/6) cervical disc arthroplasty (CDA), FA model; upper CDA (C3/4) and lower ACDF (C5/6), AF model; upper ACDF (C3/4) and lower ACDF (C5/6), FF model; upper CDA (C3/4) and lower CDA (C5/6), AA model. An initial axial load of 73.6 N was applied at the motion center using the follower load technique. A moment of 1.0 Nm was applied at the center of the C2 vertebra to simulate the overall motion of the model. The statistical analysis was conducted using STATA version 14.0. Statistical significance was defined as a p value less than 0.05. Results: The AA group had significantly greater ROM in flexion and axial rotation in other segments compared to the FA group (p < 0.05). The FA group consistently exhibited higher average intervertebral disc pressure in C2/3 during all motions compared to the AF group (p < 0.001); however, the FA group displayed lower average intervertebral disc pressure in C6/7 during all motions (p < 0.05). The AA group had lower facet joint contact stresses during extension in all segments compared to the AF group (p < 0.05). The FA group exhibited significantly higher facet joint contact stresses during extension in C2/3 (p < 0.001) and C6/7 (p < 0.001) compared to the AF group. Discussion: The use of skip-level CDA is recommended for the treatment of non-contiguous CDD. The FA construct shows superior biomechanical performance compared to the AF construct.

Standalone versus Anterior Cervical Plating for One-To-Two Level Anterior Cervical Discectomy and Fusion: A Propensity Score-Matched Comparative Study.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) can be performed with and without supportive anterior cervical plating. Fusion rates, incidence of dysphagia, and repeat surgery are concerns when performing ACDF with or without plating. We aimed to compare procedural success and outcomes between patients treated with and without cervical plating for 1-2 level ACDF. METHODS: A prospectively maintained database was retrospectively searched for patients who underwent 1-2 level ACDF surgery. Patients were divided into cohorts treated with plating and without (standalone). Propensity score matching (PSM) was performed to eliminate selection bias and control for baseline comorbidities and disease severity. Patient demographics (including age, body mass index, smoking status, diabetes mellitus, osteoporosis), disease presentation (cervical stenosis, degenerative disc disease), and operative details (number of operative levels, cage type used, intraoperative, and postoperative complications) were recorded. Outcomes assessed were fusion observed at 3, 6, and 12 months, patient-reported postoperative pain, and any repeat surgeries. Univariate analysis was performed according to data normality and variables for PSM cohorts. RESULTS: A total of 365 patients were identified (plating=289, standalone=76). After PSM, 130 patients (65 in each group) were included for final analysis. Similar mean operative times (101.3 ± 26.5-standalone; 104.8 ± 32.2-plating; P = 0.5) and mean hospital stays (1.2 ± 1.8-standalone; 0.7 ± 0.7-plating; P = 0.1) were noted. Twelve-month fusion rates were also similar (84.6%-standalone; 89.2%-plating; P = 0.6). Repeat surgery rates were equivalent (13.8%-standalone; 12.3%-plating; P = 0.8). CONCLUSIONS: In this propensity score-matched case-control study, we report comparable effectiveness and outcomes of performing 1-2 level ACDF with and without cervical plating.

Application of Neurite Orientation Dispersion and Density Imaging to Evaluate and Predict the Surgical Outcome for Degenerative Cervical Myelopathy.

OBJECTIVES: Although the neurite orientation dispersion and density imaging (NODDI) has been shown useful to evaluate the spinal cord dysfunction, there are few prospective studies on analyzing the operation recovery of degenerative cervical myelopathy (DCM) disease using NODDI. This study aims to investigate the preoperative evaluation and predictive ability of NODDI in DCM patients who received posterior cervical laminoplasty. METHODS: This prospective study included 55 patients with DCM from January to December 2017. NODDI metrics, including intracellular volume fraction (Vic), isotropic volume fraction (Viso), and orientation dispersion index (ODI) were measured at the maximally compressed (MC) level and the non-compressed C2 level in each patient at the preoperative and the 3- and 6-month postoperative follow-up stages. Neurological function was assessed using the modified Japanese Orthopaedic Association (mJOA) scoring system at each stage. Spearman's correlation and Kendall's tau-b correlation were used to analyze the relationship between NODDI metrics and mJOA scores. Wilcoxon signed rank test was used to examine the changes in the NODDI and mJOA scores between the preoperative and 6-month follow-up stages. ROC analysis was used to further evaluate the predictive capability. RESULTS: Preoperative Vic at the level of C2 has a significant correlation with the preoperative mJOA score (r = 0.278, p = 0.048). Vic and Viso at the MC level were significantly different between the preoperative period and 6-month follow-up. Viso at the MC level was correlated with the mJOA score at 6-month follow-up (r = -0.302, p = 0.044). Vic and ODI at the C2 level predicted the surgical prognosis, with areas under the receiver-operating characteristic curve of 0.663 (p = 0.042) and 0.716 (p = 0.014). CONCLUSIONS: The preoperative NODDI metrics at the C2 level are capable of evaluating the severity of spinal cord dysfunction and predict the surgical outcome.

Revision Anterior Cervical Disc Arthroplasty: A National Analysis of the Associated Indications, Procedures, and Postoperative Outcomes.

STUDY DESIGN: Retrospective study. OBJECTIVE: To examine the associated indications, procedures, and postoperative outcomes after revision ACDA. METHODS: We utilized a national database to identify adult(≥18 years) patients who underwent either a primary ACDA or removal of ACDA over a 10-year period(2008-2017). An in-depth assessment of the reasons for revision surgery and the subsequent procedures performed after the removal of ACDA was done by using both Current Procedural Terminology(CPT) and International Statistical Classification of Diseases (ICD-9,10) coding. RESULTS: From 2008 to 2017, a total of 3,350 elective, primary ACDA cases were performed. During this time, 69 patients had a revision surgery requiring the removal of ACDA. The most common reasons for revision surgery included cervical spondylosis(59.4%) and mechanical complications(27.5%). After removal of ACDA, common procedures performed included anterior cervical fusion with or without decompression(69.6%), combined anterior/posterior fusion/decompression (11.6%), and replacement of ACDA (7.2%). The indications for surgery did not vary significantly among the different procedures performed (p = 0.318). Patients requiring revision surgery for mechanical complications or those who underwent a combined surgical approach were at significantly higher risk for subsequent short-term complications (p<0.05). CONCLUSION: Over a 10-year period, the rate of revision surgery for ACDA was low (2.1%). Nearly 90% of revision cases were due to either cervical spondylosis or mechanical complications. These indications for surgery did not vary significantly among the different procedures performed. These findings will be important during the shared-decision making process for patients undergoing primary or revision ACDA.

Waste not, want not: Report of a completely calcified C1-C2 juxtafacet cyst and literature review.

BACKGROUND: Calcified juxtafacet cysts in the cervical spine are extremely rate. Such symptomatic cysts commonly cause neck pain, radiculopathy, or even myelopathy. MR and CT studies typically document cord/ root compression. On occasion, some of these cysts will spontaneously regress, while many others may warrant surgical removal. CASE DESCRIPTION: A 70-year-old male presented with a 2-year history of a progressive tetraparesis. The preoperative MR/CT studies showed a C1-C2 left extradural mass occupying more than half of the spinal canal. On MR, it was homogeneously hypointense on both T1- and T2-weighted images, while the CT showed a calcified cyst. Intraoperative and histopathological findings documented a calcified cervical juxtafacet cyst (i.e. ganglion subtype) that was fully excised without sequelae. CONCLUSION: C1-C2 juxtafacet cervical cyst should be considered when a patient presents with myelopathy due to a calcified MR/CT documented paraspinal lesion contributing to significant cervical cord/root compression.

Using the cobweb classification system as a digital location system for the neurologic compression in cervical degenerative disease.

OBJECTIVE: To provide the cobweb classification system (CCS) for the precise digital location and description of the neurological compression in cervical degenerative disease (CDD), and the reliability and the clinical subgroup analysis of the system were tested and analyzed. METHODS: The CCS consisted of three parts: compression zones (1-12), degrees (a, b) and ossification (s, m, h). Computerized tomography (CT) and magnetic resonance imaging (MRI) images from 238 CDD patients were reviewed. All compression cases were classified by five independent reviewers with varied clinical experience in spine surgery. The reliability of the CCS was tested by calculating the kappa (κ) statistics value. Finally, 74 patients with anterior cervical surgery treatment were enrolled for the clinical subgroup analysis. RESULTS: For the small compression, including single and double compression zones, there was a good interobserver reliability between the reviewers (κ coefficient = .855, P < .001). For the large compression with three or more involved zones, there was a fair reliability between the reviewers (κ coefficient = .696, P < .001). The whole intraobserver reliability was good (κ coefficient = .923, P < .001). For clinical practice, the operative time in the large compression and the m/h group was significantly longer than the small compression and the s group, respectively (P < .05), and the blood loss in the m/h group was significantly increased as well (P < .01). Though the preoperative Japanese Orthopedic Association score in Group b was lower than Group a (P < .05), all patients had achieved significant clinical improvement at last follow-up. CONCLUSIONS: The CCS can be used to provide detailed and objective descriptions of the location, extent, and severity of neurological compressions in CDD with satisfactory reliability. Surgeons should pay more attention to the patient with large zone, degree b, and ossification compression, because the operation may be more challenging.

Cervical spine degenerative disease is an independent risk factor for increased revision rate following total knee arthroplasty.

INTRODUCTION: The relationship between cervical degenerative pathology and total knee arthroplasty (TKA) revision rates is not well understood. The aim of the study was to determine whether cervical spine degenerative diseases have a role in complications following TKA within 2 years. METHODS: Data were collected from the Humana insurance database using the PearlDiver Patient Records Database from 2007-2017. Patients who had a primary TKA were identified using Current Procedural Terminology (CPT) code 27,447, and patients with degenerative cervical disease were identified using CPT and International Classification of Diseases (ICD) codes. Data on patients' demographics, comorbidities and postoperative complications were recorded and analyzed with univariate and multivariate analysis with significance set at p < 0.05. A Kaplan-Meier analysis was conducted to estimate the 1- and 2-year rates of survival free from revision. RESULTS: A total of 81,873 patients were included in this study. Following multivariate analysis, cervical spine degenerative disease patients were at increased risk of all-cause revision surgery following 1 year (OR: 1.342 95% CI: 1.149-1.569; p < 0.001) and 2 year (OR: 1.338; 95% CI: 1.184-1.512; p < 0.001). At 2 years, patients with cervical spine degenerative disease had a survival rate of 97.7%, while the survival rate was 99.2% among the non-cervical degenerative cohort. CONCLUSIONS: Based on these results, patients with cervical spine degenerative pathology should be counseled that their spinal pathology may impair outcomes following TKA.

Osteolysis after cervical disc arthroplasty.

PURPOSE: Cervical disc arthroplasty (CDA) has become an increasingly popular treatment for cervical degenerative disc disease. One potential complication is osteolysis. However, current literature on this topic appears limited. The purpose of this study is to elucidate the incidence, aetiology, consequence, and subsequent treatment of this complication. METHODS: A systematic literature review was performed according to the PRISMA guidelines. Studies discussing the causes, incidence and management of osteolysis after a CA were included. RESULTS: A total of nine studies were included. We divided these studies into two groups: (1) large case series in which an active radiological evaluation for osteolysis was performed (total = six studies), (2) case report studies, which discussed symptomatic cases of osteolysis (total = three). The incidence of asymptomatic osteolysis ranged from 8 to 64%; however, only one study reported an incidence of < 10% and when this case was excluded the incidence ranged from 44 to 64%. Severe asymptomatic bone loss (exposure of the implant) was found in less than 4% of patients. Bone loss from osteolysis appeared to occur early (< 1 year) after surgery and late (> 1 year) as well. Symptomatic patients with osteolysis often required revision surgery. These patients required removal of implant and conversion to fusion in the majority of the cases. CONCLUSIONS: Osteolysis after CDA is common; however, the majority of cases have only mild or asymptomatic presentations that do not require revision surgery. The timing of osteolysis varies significantly. This may be due to differences in the aetiology of osteolysis.

Does zero-profile anchored cage accompanied by a higher postoperative subsidence compared with cage-plate construct? A meta-analysis.

BACKGROUND: The zero-profile anchored cage (ZP) has been widely used for its lower occurrence of dysphagia. However, it is still controversial whether it has the same stability as the cage-plate construct (CP) and increases the incidence of postoperative subsidence. We compared the rate of subsidence after anterior cervical discectomy and fusion (ACDF) with ZP and CP to determine whether the zero-profile device had a higher subsidence rate. METHODS: We performed a meta-analysis of studies that compared the subsidence rates of ZP and CP. An extensive and systematic search covered the PubMed and Embase databases according to the PRISMA guidelines and identified ten articles that satisfied our inclusion criteria. Relevant clinical and radiological data were extracted and analyzed by the RevMan 5.3 software. RESULTS: Ten trials involving 626 patients were included in this meta-analysis. The incidence of postoperative subsidence in the ZP group was significantly higher than that in the CP group [15.1% (89/588) versus 8.8% (51/581), OR = 1.97 (1.34, 2.89), P = 0.0005]. In the subgroup analysis, we found that the definition of subsidence did not affect the higher subsidence rate in the ZP group. Considering the quantity of operative segments, there was no significant difference in the incidence of subsidence between the two groups after single-level fusion (OR 1.43, 95% CI 0.61-3.37, P = 0.41). However, the subsidence rate of the ZP group was significantly higher than that of the CP group (OR 2.61, 95% CI 1.55-4.40, P = 0.0003) after multilevel (≥ 2-level) procedures. There were no significant differences in intraoperative blood loss, JOA score, NDI score, fusion rate, or cervical alignment in the final follow-up between the two groups. In addition, the CP group had a longer operation time and a higher incidence of dysphagia than the ZP group at each follow-up time. CONCLUSION: Based on the limited evidence, we suggest that ZP has a higher risk of postoperative subsidence than CP, although with elevated swallowing discomfort. A high-quality, multicenter randomized controlled trial is required to validate our results in the future.

Identifying the Characteristics of Patients With Cervical Degenerative Disease for Surgical Treatment From 17-Year Real-World Data: Retrospective Study.

BACKGROUND: Real-world data (RWD) play important roles in evaluating treatment effectiveness in clinical research. In recent decades, with the development of more accurate diagnoses and better treatment options, inpatient surgery for cervical degenerative disease (CDD) has become increasingly more common, yet little is known about the variations in patient demographic characteristics associated with surgical treatment. OBJECTIVE: This study aimed to identify the characteristics of surgical patients with CDD using RWD collected from electronic medical records. METHODS: This study included 20,288 inpatient surgeries registered from January 1, 2000, to December 31, 2016, among patients aged 18 years or older, and demographic data (eg, age, sex, admission time, surgery type, treatment, discharge diagnosis, and discharge time) were collected at baseline. Regression modeling and time series analysis were conducted to analyze the trend in each variable (total number of inpatient surgeries, mean age at surgery, sex, and average length of stay). A P value <.01 was considered statistically significant. The RWD in this study were collected from the Orthopedic Department at Peking University Third Hospital, and the study was approved by the institutional review board. RESULTS: Over the last 17 years, the number of inpatient surgeries increased annually by an average of 11.13%, with some fluctuations. In total, 76.4% (15,496/20,288) of the surgeries were performed in patients with CDD aged 41 to 65 years, and there was no significant change in the mean age at surgery. More male patients were observed, and the proportions of male and female patients who underwent surgery were 64.7% (13,126/20,288) and 35.3% (7162/20,288), respectively. However, interestingly, the proportion of surgeries performed among female patients showed an increasing trend (P<.001), leading to a narrowing sex gap. The average length of stay for surgical treatment decreased from 21 days to 6 days and showed a steady decline from 2012 onward. CONCLUSIONS: The RWD showed its capability in supporting clinical research. The mean age at surgery for CDD was consistent in the real-world population, the proportion of female patients increased, and the average length of stay decreased over time. These results may be valuable to guide resource allocation for the early prevention and diagnosis, as well as surgical treatment of CDD.

Association between sagittal balance and adjacent segment degeneration in anterior cervical surgery: a systematic review and meta-analysis.

BACKGROUND: ASD is a relatively common degenerative alteration after cervical surgery which occurs above or below the fused segment. In addition, some patients may need reoperation to treat severe ASD after the primary surgery. It was considered that sagittal balance is correlated with postoperative clinical outcomes; however, few studies have reported the influence of sagittal balance on ASD. The present study is designed to investigate whether sagittal balance impacts the pathology of adjacent segment disease (ASD) in patients who undergo anterior cervical surgery for degenerative cervical disease. METHODS: Databases including Pubmed, Embase, Cochrane library, and Web of Science were used to search for literature published before June 2018. Review Manager 5.3 was used to perform the statistical analysis. Sagittal balance parameters before and after surgery were compared between patients with and without ASD. Weighted mean difference (WMD) was summarized for continuous data and P < 0.05 was set for the level of significance. RESULTS: A total of 221 patients with ASD and 680 patients without ASD from seven articles were studied in this meta-analysis. There were no significant differences in most sagittal balance parameters between the two groups, except for postoperative cervical lordosis (CL) (WMD -3.30, CI -5.91, - 0.69, P = 0.01). CONCLUSIONS: Some sagittal balance parameters may be associated with the development of ASD after anterior cervical surgery. Sufficient restoration of CL may decrease the incidence of ASD. The results in present study needed to be expanded carefully and further high-quality studies are warranted to investigate the impact of sagittal balance on ASD.

Free hand technique of cervical lateral mass screw fixation.

STUDY DESIGN: We introduce a simple free hand technique with great ease of application, without angles, measures or degrees, and without any fluoroscopic guidance. It is a safe and reproducible technique. We present our preliminary experience with the use this technique, with inimitable simplicity. PURPOSE: The primary aim of the procedure was to achieve adequate screw trajectory in an apparent challenging ease which is reproducible with a good outcome. OVERVIEW OF LITERATURE: Lateral mass screw fixation is used for posterior subaxial cervical fixation. It was described by Louis and Magerl, then by Anderson, An, and Ebraheim et al. Each one described the procedure with a unique screw entrance point and trajectory. TECHNICAL NOTE: This study is a prospective case study of 45 patients who underwent subaxial cervical lateral mass screw fixation. The screws were inserted using a free hand method. The described free hand technique was found to minimize the morbidity associated with other techniques without compromising the quality of fixation. CONCLUSIONS: Surgical experiences with this technique found it equally safe, rapid, easy, and reproducible.

A prospective randomized trial comparing anterior cervical discectomy and fusion versus plate-only open-door laminoplasty for the treatment of spinal stenosis in degenerative diseases.

OBJECTIVE: For three or more involved cervical levels, there is a debate over which approach yields the best outcomes for the treatment of multilevel cervical degenerative disease. Our objective is to compare the radiological and clinical outcomes of two treatments for multilevel cervical degenerative disease: anterior cervical discectomy and fusion (ACDF) versus plate-only open-door laminoplasty (laminoplasty). METHODS: Patients were randomized on a 1:1 randomization schedule with 17 patients in the ACDF group and 17 patients in the laminoplasty group. Clinical outcomes were assessed by a visual analog scale (VAS), Japanese Orthopedic Association (JOA) scores, operative time, blood loss, rates of complications, drainage volume, discharge days after surgery, and complications. The cervical spine curvature index (CI) and range of motion (ROM) were assessed with radiographs. RESULTS: The mean VAS score, the mean JOA score, and the rate of complications did not differ significantly between groups. The laminoplasty group had greater blood loss, a longer operative time, more drainage volume, and a longer hospital stay than the ACDF group. There were no significant differences in the CI and ROM between the two groups at baseline and at each follow-up time point. ROM in both groups decreased significantly after surgery. CONCLUSIONS: Both ACDF and laminoplasty are effective and safe treatments for multilevel cervical degenerative disease. ACDF causes fewer traumas than laminoplasty.

Is It Possible To Evaluate the Ideal Cervical Alignment for Each Patient Needing Surgery? An Easy Rule To Determine the Appropriate Cervical Lordosis in Preoperative Planning.

BACKGROUND: Cervical sagittal alignment parameters are essential to plan stages of surgery. The aims of this study were to evaluate the relationship between cervical sagittal alignment parameters and surgical outcomes after anterior cervical arthrodesis; to identify parameters linked to a better outcome; to determine the role of the T1 slope, C7 slope, cervical lordosis, and C2-C7 plumb line; and to describe an innovative method to calculate cervical lordosis. A cohort of 70 patients without cervical kyphosis was included in our retrospective study. We analyzed C7 slope, T1 slope, cervical lordosis, and the C2-C7 sagittal vertical axis (SVA). Clinical postoperative outcomes were evaluated with the Neck Disability Index (NDI) and Visual Analog Scale (VAS) score. RESULTS: Significant correlation was found between the C2-C7 SVA, C7 slope, T1 slope and the CL/C7 slope. Statistically significant differences were found between group 1 (NDI = 0; VAS = 0) and group 3 (NDI > 17; VAS > 5) regarding C2-C7 SVA (P = 0.0026), C7 slope (P = 0.0014), T1 slope (P = 0.0095) and CL/C7slope (P = 0.0012). A value less than 25 mm found in the C2-C7 SVA correlate with positive outcomes. C7 slope correlated with NDI and VAS (P = 0.0014). CL/C7 slope ratio is significantly correlated to NDI and VAS scores (ratio: -0.52; P = 0.0012). Patients with CL/C7 slope greater than 0.7 had better clinical outcomes. CONCLUSIONS: Sagittal parameters are directly correlated with clinical outcome. If C7 slope increases, higher cervical lordosis is necessary to obtain a good outcome. CL/C7 slope (0.7) multiplied by C7 slope can determine the ideal lordosis.

Adjacent segment disease requiring reoperation in cervical total disc arthroplasty: A literature review and update.

OBJECTIVE: To evaluate the difference in rate of reoperation for adjacent segment disease (ASD) between anterior cervical decompression and fusion (ACDF) and total disc replacement (TDR). METHOD: A systematic review of literature was performed using PubMed, clinicaltrials.gov, and various other search engines. Nine studies met the inclusion criteria and were used to report an estimated overall rate of reoperation secondary to ASD for both ACDF and TDR. RESULTS: Forty-six clinical trials were identified after the initial search, and 9 studies met our inclusion criteria. Although the data was not pooled due to significant variation in level of evidence and length of follow-up, the overall rate of reoperation for ASD in the TDR cohort of patients analyzed in our review was 3.1% (range: 0-7.1%) with a follow-up between 24 and 80months. In contrast, the reoperation rate for ASD in the ACDF control was 6.0% (range: 1.0-11.9%). CONCLUSION: The average reoperation rate for ASD was 3.1% for the TDR across all studies, which was lower than the reoperation rate of 6.0% in the ACDF group. Further studies and follow-up data are still needed to determine if cervical TDR preserves adjacent segment motion more efficiently than the natural history of the disease, and if it will be a durable option when compared to the already excellent results of ACDF.

The use of surgery for cervical degenerative disease in Norway in the period 2008-2014 : A population-based study of 6511 procedures.

BACKGROUND: The incidence rate of surgical treatment of cervical degenerative diseases (CDD) has increased in the USA and a large geographic variation has been shown. Little is known about such rates in Scandinavia and Europe. The aim of this population-based study was to (1) investigate annual incidence rates of operations performed in Norway, (2) to compare trends and variations in rates for surgical indications with and without myelopathy, and (3) to compare variations in the use of surgery between residential areas. METHODS: Patients operated for CDD and recorded in the Norwegian Patient Registry from 2008 to 2014 were evaluated according to residential areas (resident county and Regional Health Authority (RHA) area), age, gender, treating hospital, and whether myelopathy was present or not. Surgical rates were adjusted for age and gender. Data from private health care were also included. RESULTS: The annual surgical rates increased by 74.1 % from 2008 to 2014 (12.5/100,000 inhabitants). The largest increase was for surgical treatment of radiculopathy, 86.5 %. Surgical rates for CDD varied in 2014 with a ratio of 1.5 between the highest and lowest RHA and with a ratio of 2.5 between the different residential counties within one RHA. The treatment rates for myelopathy were relatively stable over time, but showed an increase of 2.1/100,000 (44.6 %) from 2013 to 2014. CONCLUSIONS: Our study shows that the rate of surgical treatment for radiculopathy due to CDD has increased substantially from 2008 to 2014 for all RHAs in Norway. The incidence rate for surgical treatment of myelopathy was more stable. An unexplained and moderate geographic variation was found.

A meta-analysis comparing total disc arthroplasty with anterior cervical discectomy and fusion for the treatment of cervical degenerative diseases.

PURPOSE: To evaluate the efficacy and safety of total disc arthroplasty (TDA) and anterior cervical discectomy and fusion (ACDF) for treating cervical degenerative diseases. METHODS: We conducted a comprehensive search in the electronic databases including Pubmed, Medline, EBSCO, Springer, Ovid, CNKI and Cochrane Database of Systematic Reviews. Two independent reviewers performed the data extraction from archives. All data were performed with Review Manager 5.2 software. The relative risk (RR) and its 95% confidence interval (CI) were calculated for count data. Standardized mean difference (SMD) and corresponding 95% CI for continuous outcomes were pooled. RESULTS: After applying inclusion and exclusion criteria, nine papers were included in meta-analyses. The results of the meta-analysis indicated better neurological success, better overall success, lower incidence of secondary surgical procedures and lower incidence of secondary surgical procedures in TDA group than in ACDF group. After removing a study with considerable weight, TDA group displayed lower incidence of dysphagia and dysphonia than ACDF group. CONCLUSION: This meta-analysis revealed that the clinical outcomes of TDA are equivalent or superior to ACDF.

Endoscopic Endonasal Odontoidectomy.

Odontoidectomy is the treatment of choice for irreducible ventral cervical-medullary compression. The endonasal endoscopic approach is an innovative approach for odontoidectomy. The aim of this article is to identify in which conditions this approach is indicated, discussing variants of the technique for selected cases of craniovertebral malformation with platybasia. We believe that the technical difficulties of this approach are balanced by the advantages for patients. Some conditions related to the patient and to the anatomy of the craniovertebral junction may favor adoption of the endoscopic endonasal approach, which should be considered complementary and not alternative to standard approaches.

Cervical kinematics and radiological changes after Discover artificial disc replacement versus fusion.

BACKGROUND CONTEXT: The cervical disc arthroplasty has emerged as a promising alternative to the anterior cervical discectomy and fusion (ACDF) in patients with radiculopathy or myelopathy with disc degeneration disease. The advantages of this technique have been reported to preserve the cervical mobility and possibly reduce the adjacent segment degeneration. However, no studies have compared the clinical outcomes and radiological results in patients treated with Discover artificial disc replacement to those observed in matched group of patients that have undergone ACDF. PURPOSE: We conducted this clinical study to compare the cervical kinematics and radiographic adjacent-level changes after Discover artificial disc replacement with ACDF. STUDY DESIGN: Analysis and evaluation of data acquired in a comparative clinical study. PATIENT SAMPLE: The number of patients in the Discover and ACDF group were 149 and 196, respectively. OUTCOME MEASURES: The Neck Disability Index (NDI) and visual analog scale (VAS) pain score were evaluated. The range of movement (ROM) by the shell angle, the functional segment unit and global angles were measured, and the postoperative radiological changes at adjacents levels were observed. METHODS: A total of 149 patients with symptomatic single or two-level cervical degenerative diseases received the Discover cervical artificial disc replacement from November 2008 to February 2010. During the same period, there were a total of 196 patients undergoing one or two-level ACDF. The average follow-up periods of the Discover disc group and ACDF group were 22.1 months and 22.5 months, respectively. Before surgery, patients were evaluated using static and dynamic cervical spine radiographs in addition to computerized tomography and magnetic resonance imaging. Static and dynamic cervical spine radiographs were obtained after surgery and then at 3- and 6-month follow-up. Then, the subsequent follow-up examinations were performed at every 6-month interval. The clinical results in terms of NDI and VAS scores, the parameters of cervical kinematics, postoperative radiological changes at adjacent levels, and complications in the two groups were statistically analyzed and compared. No funding was received for this study, and the authors report no potential conflict of interest-associated biases in the text. RESULTS: Although the clinical improvements in terms of NDI and VAS scores were achieved in both the Discover and ACDF group, no significant difference was found between the two groups for both single- (VAS p=.13, NDI p=.49) and double-level surgeries (VAS p=.28, NDI p=.21). Significant differences of cervcial kinematics occurred between the Discover and the ACDF group for both the single- and double-level surgeries at the operative segments (p<.001). Except the upper adjacent levels for the single-level Discover and ACDF groups (p=.33), significant increases in adjacent segment motion were observed in the ACDF group compared with the minimal ROM changes in adjacent segment motion noted in the Discover group, and the differences between the two groups for both single and double-level procedures were statistically significant (p<.05). There were significant differences in the postoperative radiological changes at adjacent levels between the Discover and ACDF groups for the single-level surgery (p<.001, χ(2)=18.18) and the double-level surgery (p=.007, χ2=7.2). No significant difference of complications was found between the Discover and ACDF groups in both single (p=.25, χ2=1.32) and double-level cases (p=.4, χ2=0.69). CONCLUSIONS: The adjacent segment ROM and the incidence of radiographic adjacent-level changes in patients undergoing ACDF were higher than those undergoing Discover artificial disc replacement. The cervical mobility was relatively well maintained in the Discover group compared with the ACDF group, and the Discover cervical disc arthroplasty can be an effective alternative to the fusion technique.