Cervical Disc Arthroplasty Group Research Articles

Cervical Disc Arthroplasty (CDA) versus Anterior Cervical Discectomy and Fusion (ACDF) for Two-Level Cervical Disc Degenerative Disease: An Updated Systematic Review and Meta-Analysis.

Background: Anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) are both considered to be efficacious surgical procedures for treating cervical spondylosis in patients with or without compression myelopathy. This updated systematic review and meta-analysis aimed to compare the outcomes of these procedures for the treatment of cervical degenerative disc disease (DDD) at two contiguous levels. Methods: The PubMed, EMBASE, and Cochrane CENTRAL databases were searched up to 1 May 2023. Studies comparing the outcomes between CDA and ACDF in patients with two-level cervical DDD were eligible for inclusion. Primary outcomes were surgical success rates and secondary surgery rates. Secondary outcomes were scores on the Neck Disability Index (NDI) and Visual Analogue Scale (VAS) for neck and arm pain, as well as the Japanese Orthopaedic Association (JOA) score for the severity of cervical compression myelopathy and complication rates. Results: In total, eight studies (two RCTs, four retrospective studies, and two prospective studies) with a total of 1155 patients (CDA: 598; ACDF: 557) were included. Pooled results revealed that CDA was associated with a significantly higher overall success rate (OR, 2.710, 95% CI: 1.949-3.770) and lower secondary surgery rate (OR, 0.254, 95% CI: 0.169-0.382) compared to ACDF. In addition, complication rates were significantly lower in the CDA group than in the ACDF group (OR, 0.548, 95% CI: 0.326 to 0.919). CDA was also associated with significantly greater improvements in neck pain VAS than ACDF. No significant differences were found in improvements in the arm VAS, NDI, and JOA scores between the two procedures. Conclusions: CDA may provide better postoperative outcomes for surgical success, secondary surgery, pain reduction, and postoperative complications than ACDF for treating patients with two-level cervical DDD.

Cervical Disc Arthroplasty for the Treatment of Noncontiguous Cervical Degenerative Disc Disease: Results of Mid- to Long-Term Follow-up.

The long-term results of cervical disc arthroplasty (CDA) for noncontiguous cervical degenerative disc disease (CDDD) are still uncertain. Moreover, it is unclear whether CDA delays or avoids the degeneration of the intermediate segment (IS), leading to controversy in the field. Therefore, this study aimed to investigate the mid- to long-term clinical and radiographic outcomes of CDA in treating noncontiguous CDDD and to explore whether the IS degenerated faster after CDA than other non-surgically treated adjacent segments. We retrospectively analyzed patients with noncontiguous CDDD who underwent CDA in our department between January 2008 and July 2018. The patients were divided into the CDA and hybrid surgery (HS) groups, and clinical and radiographic outcomes were evaluated at routine postoperative intervals. Clinical outcomes were assessed using the Japanese Orthopaedic Association (JOA), neck disability index (NDI), and visual analogue scale (VAS), while radiographic outcomes included cervical lordosis (CL), C2-C7 range of motion (ROM), segmental ROM, and disc angle (DA) at the arthroplasty level. Complications were also evaluated.Pre- and postoperative values were compared using paired t-tests or Wilcoxon rank-sum tests. Independent Student t-tests or Mann-Whitney U tests analyzed continuous data between CDA and HS groups, while chi-square or Fisher exact tests assessed categorical data. Sixty-four patients with noncontiguous CDDD, with 31 in the CDA group and 33 in the HS group, were evaluated. The mean follow-up time was over 70 months. The most frequently involved levels were C4/5 and C5/6. Both groups showed significant improvements in JOA, NDI, and VAS values after surgery. Although CL was maintained, the CL in the CDA group was consistently lower than that in the HS group (p < 0.05). There was a significant decrease in C2-C7 ROM (p < 0.05), but at the last follow-up, the C2-C7 ROM in the CDA group was greater than that in the HS group (p < 0.05). At the last follow-up, 44.3% of arthroplasty levels had developed heterotopic ossification (HO), and 48.45% had developed anterior bone loss (ABL). In addition, adjacent segment degeneration (ASDeg) was observed in the IS (22.7%), superior adjacent segment (20.6%)and inferior adjacent segment (21.9%). CDA or CDA combined with fusion are viable treatments for noncontiguous CDDD, with satisfactory outcomes after mid-to-long-term follow-up. ASDeg is similar in non-surgical segments after 70 months of follow-up. ROM of the IS issimilar to preoperative levels, indicating CDA does not increase the risk of IS degeneration.

Mid-term and Long-term Outcomes After Total Cervical Disk Arthroplasty Compared With Anterior Cervical Discectomy and Fusion: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

A meta-analysis of randomized controlled trials (RCTs). The aim of this study was to compare mid-term to long-term outcomes of cervical disk arthroplasty (CDA) with those of anterior cervical discectomy and fusion (ACDF) for the treatment of symptomatic cervical degenerative disk disease. After ACDF to treat symptomatic cervical degenerative disk disease, the loss of motion at the index level due to fusion may accelerate adjacent-level disk degeneration. CDA was developed to preserve motion and reduce the risk of adjacent segment degeneration. Early-term to mid-term clinical outcomes from RCTs suggest noninferiority of CDA compared with ACDF, but it remains unclear whether CDA yields better mid-term to long-term outcomes than ACDF. Two independent reviewers searched PubMed, Embase, and the Cochrane Library for RCTs with at least 60 months of follow-up. The risk ratio or standardized mean difference (and 95% CIs) were calculated for dichotomous or continuous variables, respectively. Eighteen reports of 14 RCTs published in 2014-2023 were included. The pooled analysis demonstrated that the CDA group had a significantly greater improvement in neurological success and Neck Disability Index than the ACDF group. The ACDF group exhibited a significantly better improvement in the Short Form-36 Health Survey Physical Component Summary than the CDA group. Radiographic adjacent segment degeneration was significantly lower in the CDA group at 60- and 84-month follow-ups; at 120-month follow-up, there was no significant difference between the 2 groups. Although the overall rate of secondary surgical procedures was significantly lower in the CDA group, we did not observe any significant difference at 60-month follow-up between the CDA and ACDF group and appreciated statistically significant lower rates of radiographic adjacent segment degeneration, and symptomatic adjacent-level disease requiring surgery at 84-month and 108- to 120-month follow-up. The rate of adverse events and the neck and arm pain scores in the CDA group were not significantly different from those of the ACDF group. In this meta-analysis of 14 RCTs with 5- to 10-year follow-up data, CDA resulted in significantly better neurological success and Neck Disability Index scores and lower rates of radiographic adjacent segment degeneration, secondary surgical procedures, and symptomatic adjacent-level disease requiring surgery than ACDF. ACDF resulted in improved Short Form-36 Health Survey Physical Component Summary scores. However, the CDA and ACDF groups did not exhibit significant differences in overall changes in neck and arm pain scores or rates of adverse events.

Cervical disc arthroplasty for magnetic resonance-evident cervical spondylotic myelopathy: comparison with anterior cervical discectomy and fusion.

Anterior cervical discectomy and fusion (ACDF) is a standard surgical approach for cervical spondylotic myelopathy (CSM) caused by disc herniations. Although cervical disc arthroplasty (CDA) has become, in the past decade, a viable alternative to ACDF in selected patients, the differences among patients with CSM treated with CDA and ACDF remain elusive. The effectiveness of motion preservation devices in CSM is also unclear. Adult patients who underwent 1- or 2-level CDA or ACDF between 2007 and 2021 were retrospectively reviewed. Patients whose preoperative T2-weighted MRI demonstrated increased intramedullary signal intensity (IISI) were included and analyzed for the following: comparison of the length of IISI on pre- and postoperative MR images as well as range of motion (ROM) at the indexed levels between the CDA and ACDF groups. Measurement for clinical outcomes included the visual analog scale (VAS) of the arm and neck, the Neck Disability Index, and modified Japanese Orthopaedic Association scores. Perioperative clinical data were also compared between the two groups. A total of 122 patients were allocated to the CDA group and 108 to the ACDF group, with mean follow-ups of 46.6 and 39.0 months, respectively. Patients in the CDA group were younger than those in the ACDF group (47.64 ± 12.40 vs 61.73 ± 12.25 years, p < 0.001) (mean ± SD). The ACDF group had more 2-level surgery compared to the CDA group (p = 0.002). Both groups had significant regression of IISI on postoperative MRI compared to that of preoperative imaging (CDA: 1.23 ± 0.84 to 0.28 ± 0.39 cm; ACDF: 1.07 ± 0.60 to 0.37 ± 0.42 cm; both p < 0.001). The decrease in the length of IISI was similar between the two groups (p = 0.058). The postoperative ROM was well preserved in the CDA group (superior to ACDF, which yielded minimal ROM postoperatively). Both the CDA and ACDF groups demonstrated improvement in Neck Disability Index and modified Japanese Orthopaedic Association scores at 24 months postoperatively. The CDA group had significant improvements on VAS scores, whereas the improvement did not reach significance for the ACDF group at 24 months postoperatively. Significant shortening of IISI on T2-weighted MRI was demonstrated after both CDA and ACDF. At 24 months postoperatively, all clinical outcomes demonstrated improvement after both strategies, except that the VAS score was not significantly improved for ACDF. Therefore, CDA is a safe and effective option for patients with MR-evident CSM.

20-year Clinical Outcomes of Cervical Disc Arthroplasty: A Prospective, Randomized, Controlled Trial.

Prospective, Randomized, Controlled Trial. To compare clinical outcomes of anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) at 20 years. Concern for adjacent level disease after ACDF prompted development of CDA. 47 patients with single level cervical radiculopathy were randomized to either BRYAN CDA or ACDF for an FDA IDE trial. At 20 years, patient reported outcomes, including visual analog scales (VAS) for neck and arm pain, neck disability index (NDI), and reoperation rates were analyzed. Follow-up rate was 91.3%. Both groups showed significantly better NDI, VAS arm pain and VAS neck pain scores at 20 years versus preoperative scores. Comparing CDA versus ACDF, there was no difference at 20 years in mean scores for NDI [11.1 (SD 14.1) vs. 19.9 (SD 17.2), P=0.087], mean VAS arm pain [0.9 (SD 2.4) vs. 2.3 (SD 2.8), P=0.095], or mean VAS neck pain [1.2 (SD 2.5) vs. 2.9 (3.3), P=0.073]. There was a significant difference between CDA versus ACDF groups in the change in VAS neck pain score between 10 and 20 years [respectively, -0.4 (SD 2.5) vs. 1.5 (SD 2.5), P=0.030]. Reoperations were reported in 41.7% of ACDF patients and 10.0% of CDA patients (P=0.039). Both CDA and ACDF are effective in treating cervical radiculopathy with sustained improvement in NDI, VAS neck and VAS arm pain at 20 years. CDA demonstrates lower reoperation rates than ACDF. There were no failures of the arthroplasty device requiring reoperation at the index level. Symptomatic non-union rate of ACDF was 4.2% at 20 years. Despite a higher reoperation rate in the CDA group versus ACDF group, there was no difference in the 20-year NDI, VAS Neck and VAS arm pain scores.

Disc prosthesis versus fusion with cage in single level cervical degenerative spine disease – A retrospective case-control patient reported outcome study

AimTo compare the clinical outcome of single level cervical degenerative spine disease treated surgically with motion preserving anterior cervical disc arthroplasty versus anterior cervical discectomy and fusion (ACDF). MethodsPatients treated with cervical disc arthroplasty at Aalborg University Hospital and ACDF at Aarhus University Hospital were matched 1:2.Primary outcome measures were Neck Disability Index (NDI), EQ-5D-3 L and Numeric rating scale (NRS) for arm- and neck pain.Data was collected by telephone interviews regarding present and retrospective data. Results50 patients treated with cervical disc arthroplasty were matched to 100 ACDF patients covering November 2011 to December 2018.Mean improvements for NRS neck pain three-months postoperative, and NDI were significantly better in the cervical disc arthroplasty group, with intergroup differences of 1.56 (p = 0.02) and 5.01 (p = 0.01) respectively.A subgroup analysis of the half of the cohort with the longest follow-up (mean 7.6 years) showed, in favour of cervical disc arthroplasty, mean improvements of NDI: 8.80 (p = 0.00), EQ5D: − 0.19 (p = 0.04), NRS neck three months follow-up: 3.70 (p = 0.00) and long follow-up: 2.54 (p = 0.01) and NRS arm three months follow-up: 2.02 (p = 0.01).Radiologic examination indicated preserved mobility in 80% of the implanted protheses at 24-month post-surgical follow-up. ConclusionSurgical treatment of one level degenerative cervical spine disease with cervical disc arthroplasty or anterior cervical discectomy and fusion has a similar good clinical outcome after a mean follow-up of 5.6 years.However, cervical disc arthroplasty displayed long-term superiority in the half of the cohort with the longest follow-up time averaging 7.6 years.

Outcomes of cervical arthroplasty versus anterior cervical arthrodesis: a systematic review and meta-analysis of randomized clinical trials with a minimum follow-up of 7-year.

Compare the outcomes of randomized clinical trials of cervical disc arthroplasty (CDA) versus anterior cervical discectomy with fusion (ACDF), with a minimum follow-up of 7years. Nine randomized clinical trials were selected. The clinical, radiological, and surgical outcomes were analyzed, including functional and pain scores, range of motion, adjacent segment degeneration, adverse events, and need for reoperation. 2664 patients were included in the study. Pooled results indicated that the CDA group had a significantly higher overall success rate (p < 0.001), a higher improvement in the neck disability index (NDI) (p = 0.002), less VAS arm pain (p = 0.01), and better health questionnaire SF-36 physical component (p = 0.01) than ACDF group. Likewise, the pooled results indicated a significantly higher motion rate (p < 0.001), less adjacent syndrome (p < 0.05), and a lower percentage of reoperation (p < 0.001) in the CDA group. There were no significant differences between the CDA and ACDF groups in the neck pain scale (p = 0.11), the health questionnaire SF-36 mental component (p = 0.10), and in adverse events (p = 0.42). In long-term follow-up, CDA showed a better overall success rate, better improvement in NDI, less VAS arm pain, better health questionnaire SF-36 physical component, a higher motion rate, less adjacent syndrome, and less reoperation rate than ACDF. No significant differences were found in the neck pain scale, SF-36 mental component, and in adverse events.

P36. Multilevel posterior cervical foraminotomy associated with increased perioperative infection rates relative to anterior cervical discectomy with fusion and cervical disc arthroplasty

P36. Multilevel posterior cervical foraminotomy associated with increased perioperative infection rates relative to anterior cervical discectomy with fusion and cervical disc arthroplasty

Cervical Alignment Analysis Comparing Two-Level Cervical Disc Arthroplasty with Anterior Cervical Discectomy and Fusion with Anterior Plate Fixation

This study assesses cervical alignments after 2-level cervical disc arthroplasty (CDA) versus anterior cervical discectomy and fusion (ACDF) with anterior plate fixation. Eighty-two patients who underwent 2-level CDA or ACDF in 2014-2019 were identified. Cervical alignment parameters were compared between the 2 cohorts. Subgroup analyses were performed to determine factors that differentiate alignment outcomes between the 2 procedures. Although both cohorts achieved significant focal lordosis (FL) and overall cervical lordotic (CL) gains, CDA cohorts achieved significantly greater 12-month FL gain (P= 0.022). However, in a multivariate analysis controlling for preoperative variables, FL gain was no longer significant. Although the CDA cervical sagittal vertical axis (cSVA) significantly improved at 3 (P= 0.030) and 12 (P= 0.007) months, these improvements were not superior to the ACDF cSVA. Male patients undergoing CDA achieved greater 12-month CL gain. Patients undergoing CDA with body mass index >25 kg/m2 achieved greater 12-month FL gain. Patients undergoing CDA with symptom duration >12 months achieved greater FL gain at 3 and 12 months. Patients undergoing CDA with high baseline T1 slope or cSVA achieved greater 12-month cSVA reduction. Clinical outcomes were comparable between the 2 cohorts. Unlike the ACDF group, CL gain in the CDA group was significantly correlated with the cSVA reduction, which was associated with significant improvement in the Neck Disability Index, arm pain, and 12-Item Short-Form Mental Component Scores. Heterotopic ossification was not found to significantly affect patient outcome and cervical alignment in both cohorts. ACDF and CDA are viable options for 2-level degenerative disc disease in carefully selected patients. Both approaches produced equivalent postoperative alignment changes in a 2-level operation.

Hybrid surgery: a comparison of early postoperative outcomes between anterior cervical discectomy and fusion and cervical disc arthroplasty.

Hybrid surgery (HS) is the combination of anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) at different levels in the same operation. The aim of this study was to investigate perioperative variables, 30-day postoperative outcomes, and complications of HS in comparison with those of CDA and ACDF. The authors queried the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) registry for patients who underwent multilevel primary HS, CDA, and ACDF for degenerative disc disease from 2015 to 2019. The authors compared these three operations in terms of 30-day postoperative outcomes, specifically readmission and reoperation rates, discharge destination, and complications. This analysis included 439 patients who underwent HS, 976 patients who underwent CDA, and 27,460 patients who underwent ACDF. Patients in the HS and CDA groups were younger, had fewer comorbidities, and myelopathy was less often the indication for surgery compared with patients who underwent ACDF. For the HS group, the unplanned readmission rate was 0.7%, index surgery-related reoperation rate was 0.3%, and nonroutine discharge rate was 2.1%. Major and minor complications were also rare, with rates of 0.2% for each. The mean length of stay in the HS group was 1.5 days. The association of HS with better outcomes in univariate analysis was not evident after adjustment for confounding factors. The authors found that HS was noninferior to ACDF and CDA in terms of early postoperative outcomes among patients treated for degenerative disc disease.

Surgical Treatment of Single Level Cervical Radiculopathy: A Comparison of Anterior Cervical Decompression and Fusion (ACDF) Versus Cervical Disk Arthroplasty (CDA) Versus Posterior Cervical Foraminotomy (PCF).

This was a retrospective cohort study. The objective of this study is to retrospectively compare the clinical outcomes, complication rates, and reoperation rates among the 4 treatments in patients with cervical radiculopathy. Surgical options for cervical radiculopathy include anterior cervical discectomy and fusion (ACDF), open posterior cervical foraminotomy (O-PCF), minimally invasive posterior cervical foraminotomy (MI-PCF), and cervical disk arthroplasty (CDA). Retrospective chart review after Review Board approval. Of the 384 patients in the study-257 ACDF, 18 O-PCF, 52 MI-PCF, and 56 CDA. Information was obtained from the charts and compared between the groups. Patients above 18 years of age with single-level, unilateral cervical radiculopathy correlating with magnetic resonance imaging, failure of nonoperative management, and 1-level ACDF, O-PCF, MI-PCF, or CDA with >24 months of follow-up. Neck Disability Index (NDI), Visual Analog Score neck and arm pain, minimum clinically significant difference (MCID), complication rates, and reoperation rates. Operative time was significantly shorter for MI-PCF. Median estimated blood loss was small, but greater with O-PCF compared with other interventions. The length of hospital stay was longest for the ACDF group. At 2 years' follow-up, 36 subjects (9%) had subsequent neck surgery. The most common indication for additional surgery was recurrent symptoms (3.4%) followed by adjacent segment disease (2.6%), pseudoarthrosis (2.1%), adjacent segment disease + pseudoarthrosis (0.5%), and implant-related complications (0.3%). There was no statistically significant difference in complication rates between groups. MCID in NDI was achieved in 40% of MI-PCF subjects, 42% of O-PCF subjects, 66% of CDA subjects and 46% of ACDF subjects. All 4 treatment options confer good clinical results on patients for cervical radiculopathy. Intraoperative and postoperative complications were low and comparable in all 4 groups. MI-PCF had the shortest surgical time and length of hospital stay. More CDA patients achieved MCID in NDI compared with the others, and the rate for additional surgery at 2 years was lowest in the CDA group.

Impact of Cervical Disc Arthroplasty vs Anterior Cervical Discectomy and Fusion on Driving Disability: Post Hoc Analysis of a Randomized Controlled Trial With 10-Year Follow-Up

Driving an automobile requires the ability to turn the neck laterally. Anecdotally, patients with multilevel fusions often complain about restricted turning motion. The purpose of this study was to compare the effectiveness of cervical disc arthroplasty (CDA) with anterior cervical discectomy and fusion (ACDF) on driving disability improvement at 10-year follow-up after a 2-level procedure. In the original randomized controlled trial, patients with cervical radiculopathy or myelopathy at 2 levels underwent CDA or ACDF. The driving disability question from the Neck Disability Index was rated from 0 to 5 years preoperatively and up to 10 years postoperatively. Severity of driving disability was categorized into "none" (score 0), "mild" (1 or 2), and "severe" (3, 4, or 5). Score and severity were compared between groups. Out of 397 patients, 148 CDA and 118 ACDF patients had 10-year follow-up. Driving disability scores were not different between the groups preoperatively (CDA: 2.65; ACDF: 2.71, P = 0.699). Postoperatively, the scores in the CDA group were significantly lower than those in the ACDF group at 5 (0.60 vs 1.08, P ≤ 0.001) and 10 years (0.66 vs 1.07, P = 0.001). Mean score improvement in the CDA group was significantly greater than the ACDF group at 10-year follow-up (-1.94 vs -1.63, P = 0.003). The majority of patients reported severe driving disability (CDA: 56.9%, ACDF: 58.0%, P = 0.968) before surgery. After surgery, a greater proportion of patients in the CDA group had neck pain-free driving compared with the ACDF group at 5 (63.3% vs 41.8%, P < 0.001) and 10 years (61.8% vs 41.2%, P = 0.003). In patients with cervical radiculopathy/myelopathy and 2-level disease, CDA provided greater improvements in driving disability as compared with ACDF at 10-year follow-up. This is the first report of its kind. This finding may be attributable to preservation of motion associated with CDA. This study provides valuable information regarding the improvement of driving disability after both CDA and ACDF. It demonstrates that both procedures result in significant improvements, with CDA resulting in even better improvements than ACDF, up to 10 year follow-up.

Current Concepts of Cervical Disc Arthroplasty

Radiculopathy and myelopathy resulting from degenerative disc disease are currently treated with anterior cervical discectomy and fusion (ACDF), but there is a high incidence of adjacent segment disease after treatment. With recent advances in cervical disc arthroplasty (CDA), we performed a review of published articles, examining the latest clinical data on the efficacy, safety, and complications of the current cervical disc devices on the market. We focused on the long-term follow up data of single-level, multi-level, and hybrid CDA as compared to ACDF, paying close attention to the newest cervical disc devices. A search was performed utilizing PubMed, Google Scholar, and Clinical Key to identify articles on 1-level, 2-level, and hybrid approaches to CDA. The articles were reviewed by two authors for relevance and power with higher emphasis placed on FDA IDE trials. The results conclude that CDA has an equivalent or improved clinical outcome when compared with ACDF with improved patient reported neck disability indexes and VAS neck pain scale. CDA also has lower rates of dysphagia, adjacent segment disease, and lower rates of reoperation when compared to ACDF. The data suggest there is no increased rate of reoperation in patients treated with multilevel CDA when compared to ACDF. In addition, the data from the limited clinical trials suggest that hybrid CDA and ACDF is safe and decreases risk of ASD. CDA has been shown to be effective and safe with low complication rates. However, the data are of low quality, and more hybrid studies must be performed in the future to confirm these findings. The reduction in overall postsurgical complications including ASD and in the need for additional surgery in the CDA group. 3.

Cervical disc arthroplasty for Klippel-Feil syndrome

ObjectiveKlippel-Feil syndrome (KFS) is a congenital musculoskeletal condition characterized by improper segmentation of the cervical spine. This study aimed to evaluate outcomes of KFS patients who underwent cervical disc arthroplasty (CDA). MethodsConsecutive patients who underwent anterior cervical surgery were retrospectively reviewed. Those patients with KFS who received discectomy adjacent to the congenitally fused vertebral segments were extracted and grouped into either the fusion or the CDA group. Clinical and radiological evaluations included visual analog scales, Neck Disability Index (NDI), Japanese Orthopedic Association (JOA) scores, C2–7 range of motion (ROM), C2–7 Cobb angle, C2–7 sagittal vertical axis (SVA), and T1-slope. ResultsAmong 2320 patients, there were 41 with KFS (prevalence = 1.77%), who were younger than the entire cohort (53.3 vs 56.4 years). Thirty KFS patients had adjacent discs and were grouped into the CDA and fusion groups (14 vs 16). Type-I KFS with C3–4 involvement was the most common for both groups (92.8% vs 81.2% with 57% vs 50%, respectively). Post-operation, both groups demonstrated improvement of all the patient reported outcomes. The C2–7 ROM significantly decreased in the fusion group than that of pre-operation (12.8 ± 6° vs 28.1 ± 11.5°). In contrast, the CDA group successfully preserved C2–7 and segmental ROM without additional complications. ConclusionsKFS is rare (prevalence = 1.77%) among cervical spine surgery patients, and it rarely affects the overall cervical spinal alignment, except that it decreases segmental mobility. CDA is a feasible option for KFS because it not only avoids long-segment fusion but also preserves segmental and global mobility.

Cervical disc arthroplasty versus anterior cervical discectomy and fusion for the treatment of single-level disc degenerative disease with preoperative reversible kyphosis

ObjectiveWhether and when cervical disc arthroplasty (CDA) could be indicated for preoperative cervical spine kyphosis is unclear. The purpose of the study was to compare the clinical and radiological outcomes of single-level CDA and single-level anterior cervical discectomy and fusion (ACDF) in the patient with preoperative reversible kyphosis. Patients and methodsFrom 2014–2018, patients who underwent single-level CDA and single-level ACDF were consecutively reviewed. The Japanese Orthopedic Association score, Neck Disability Index and VAS were used to evaluate clinical outcomes. Range of motion (ROM), C2-7 Cobb angle, functional spinal unit (FSU) angle, and heterotopic ossification (HO) were assessed. ResultsThirty-eight CDA patients (a mean follow-up of 39.8 months) and 42 ACDF patients (37.6 months) with preoperative reversible kyphosis were included. Both groups had significant improvements in clinical outcomes, without statistically significant differences. Before surgery, there was no significant difference in cervical alignment and ROM between groups. After surgery, both groups had a significant increase in C2-7 angle and FSU without significant inter-group differences. At the last follow-up, CDA group consisted of 5 cases of lordosis, 11 cases of kyphosis and 22 cases of straight spine, while the corresponding case number in ACDF group was 4, 12 and 26 (P = 0.866). The C2-7 ROM was preserved in both groups. The segmental ROM of CDA group decreased mildly from 8.3° preoperatively to 5.1° finally, whereas the segmental ROM of ACDF group decreased significantly to nearly zero. 60.5 % (23/38) patients in CDA group developed HO with 9 levels of grade Ⅲ and 3 levels of grade Ⅳ. ConclusionFor the patients with single-level disc degenerative disease and preoperative reversible kyphosis, both CDA and ACDF achieved satisfactory and comparable clinical results. CDA was non-inferior to ACDF regarding the radiological outcomes of cervical alignment. Patients in CDA group had a relatively high incidence of HO formation.

Revision Anterior Cervical Discectomy and Fusion and Revision Cervical Arthroplasty Are Associated with Similar Outcomes: Real-World Analysis from a National Quality Registry.

To utilize a national surgical quality registry to compare 30-day quality outcomes between repeat anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA). The National Surgical Quality Improvement Project (NSQIP) Participant User Files (PUF) for the years 2005-2018 were queried for patients undergoing repeat ACDF and CDA using current procedural terminology (CPT) and International Classification of Disease (ICD)-9th version codes. We compared demographic and baseline clinical characteristics, operative characteristics, 30-day readmissions, reoperations, and complications between the two groups. We also performed multivariable analyses to assess the impact of the type of repeat procedure on outcomes of interest. A total of 3,957 patients were identified, of which 182 underwent revision/removal of arthroplasty, while 3,775 underwent revision or removal of fusion. Up to 4.6% of patients (n=179) in the repeat ACDF group had a complication, compared to 0.5% (n=1) in the CDA group. The 30-day readmission rate was found to be similar between the two groups (repeat-ACDF, 3.8% (n=145), vs. repeat-CDA, 2.2% (n=4); p=0.23). Similarly, 30-day reoperation rate was also not found to be different between the two groups (repeat-ACDF, 3.9% (n=149) vs. repeat-CDA, 2.7% (n=5); p=0.39). On multivariable analysis, removal or revision ACDF was found to be only significantly associated with an increased risk of 30-day complications (OR, 8.00; 95% CI, 1.07-59.79; p=0.04). Repeat ACDF or repeat CDA can be performed safely and are associated with optimal 30-day outcomes, comparable to those of index procedures. However, patients undergoing revision ACDF may be slightly more likely to have complications than those undergoing revision CDA.

76. Reduction in opioid medication use after arthroplasty with Prestige LP cervical disc as compared to ACDF in patients with two-level surgery: a randomized study with 10-year follow-up

BACKGROUND CONTEXT Evaluation of 10-year clinical safety and effectiveness of cervical disc arthroplasty (CDA) using the Prestige LP™ disc to treat degenerative cervical spine disease at two adjacent levels has been completed and published. One of the contributing factors to the current opioid crisis in the U. is increased opioid prescription for back and neck pain. Better surgical outcomes may lead to less use of pain medications for CDA patients. PURPOSE To compare narcotic medication use between cervical disc arthroplasty (CDA) with the Prestige LP disc and anterior cervical discectomy and fusion (ACDF) at two levels. STUDY DESIGN/SETTING Multicenter, prospective, randomized, controlled, FDA-approved clinical trial. PATIENT SAMPLE A total of 397 subjects having 2-level intractable cervical radiculopathy and/or myelopathy were randomized to receive CDA (n=209) or ACDF (n=188) in an FDA-regulated clinical trial. The 10-year follow-up rate was 86% after excluding subjects at sites not participating in the PAS study, deaths, and withdrawals. OUTCOME MEASURES Subject ratings of use of pain medications for neck/arm pain, respectively for each of four types of medications: (1) weak narcotic, (2) strong narcotic, (3) non-narcotic, and (4) muscle relaxant, in a frequency scale: “not at all,” “once a week/as needed,” “once a couple of days,” “once or twice a day,”, and “three times or more a day.” Weak and strong narcotic medication use was combined for a total narcotic use score and further categorized into “ METHODS Data were obtained during the FDA-approved clinical trial, and although not considered as safety or efficacy outcomes for the trial, data were later analyzed for the current study. At preoperative and all postoperative visits up to 10 years, subjects were asked how often during the last week they used pain medications. Pain medication use was statistically compared between CDA and control group ACDF patients at 6 weeks, 3 and 6 months, and 1, 2, 3, 5, 7, and 10 years postoperatively. RESULTS Prevalence of preoperative use of narcotic medications once or more a day was not significantly different between the treatment groups (47.8% for CDA and 44.4% for ACDF). Prevalence decreased substantially for both groups after surgery, but was significantly lower for CDA than ACDF (p CONCLUSIONS The percentage of subjects who used opioid medications once or more a day after receiving the Prestige LP CDA was statistically lower than that in the ACDF group overall and at most postoperative time points. The greater clinical outcome improvements shown in the clinical trial may have led to less use of narcotic medications for CDA patients. For future studies, the use of narcotics after surgery might be considered as a treatment outcome in addition to patient-reported functional and pain outcomes. FDA DEVICE/DRUG STATUS Prestige LP™ Disc, approved for 2-level cervical disc arthroplasty in 2016 (Approved for this indication).

Two-Level Anterior Cervical Discectomy and Fusion Versus Cervical Disc Arthroplasty-Long-Term Evidence Update.

Multiple studies have highlighted the motion-sparing benefits of single-level cervical disc arthroplasty (CDA) compared with anterior cervical discectomy and fusion (ACDF). However, few studies have reviewed multilevel ACDF versus CDA. Several recent studies have midterm and even long-term data available comparing 2-level ACDF versus CDA. We reviewed 3 reports from 2 large randomized, prospective Food and Drug Administration investigational drug exemption trials looking at 2-level CDA versus ACDF, which provide the bulk of the available midterm to long-term, high-level evidence for the topic. We also present several smaller and/or shorter-term studies. One 5-year study showed that, while both CDA and ACDF showed significant improvement in patient-reported outcome scores, CDA demonstrated greater improvement in Neck Disability Index (NDI) scores than ACDF (mean = -37 versus mean = -28, P = .0003), were more likely to be satisfied (96.4% versus 89.5%, P = .04), had fewer secondary surgeries (4% versus 16.2%, P = .0003), had fewer adjacent level reoperations (3.1% versus 11.4%), and developed less adjacent segment degeneration (50.7% versus 90.5%, P < .0001). Adverse events occurred more frequently with ACDF (8.6% versus 4.4%).Similarly, Lanman et al [Lanman TH, Burkus JK, Dryer RG, Gornet MF, McConnell J, Hodges SD. Long-term clinical and radiographic outcomes of the Prestige LP artificial cervical disc replacement at 2 levels: results from a prospective randomized controlled clinical trial. J Neurosurg Spine. 2017;27(1):7-19] showed that, at 7 years, while both groups demonstrated improvement in patient-reported outcomes, CDA had greater improvement in regard to NDI, neck pain, and Short Form (36) Physical Component Summary scores (each P < .001), had higher rates of satisfaction (94.8% versus 92.6%), had lower rate of secondary surgery at treated levels (4.2% versus 14.7%), and had a lower, albeit not statistically significant, rate of secondary surgeries at adjacent levels (6.5% versus 12.5%). Adverse events were more common with ACDF (7.2% versus 3.2%).More recently, Gornet et al [Gornet MF, Lanman TH, Burkus JK, et al. Two-level cervical disc arthroplasty versus anterior cervical discectomy and fusion: 10-year outcomes of a prospective, randomized investigational device exemption clinical trial. J Neurosurg Spine. 2019;31:508-518.] in 2019 reported 10-year data from the same clinical trial as the Lanman et al report comparing 2-level CDA (209 patients) versus ACDF (188 patients). With >84% follow-up for both groups at 10 years, they found that CDA demonstrated a statistically significantly improved rate of overall success (84% versus 62%) as compared with ACDF. Greater improvements were seen in several other outcome measures for CDA, including NDI, neurological success, and neck pain scores. The CDA group had a lower rate of serious implant-related adverse events and demonstrated a lower rate of needing a secondary surgery at an adjacent level, 9% versus 18% in the ACDF group. Results of 2 large randomized trials suggest similar-to-improved patient reported outcomes for multilevel CDA versus ACDF maintained out to midterm to long-term follow-up of 5-10 years, with lower rates of revision surgery at index and adjacent levels and lower rates of serious adverse device-related events. 5. Comparison of the safety and efficacy of multi-level cervical disc arthroplasty and cervical discectomy and fusion.

Does Fusion Affect Anterior Bone Loss in Adjacent Cervical Disc Arthroplasty in Contiguous Two-Level Hybrid Surgery?

To investigate whether anterior bone loss (ABL) in cervical discarthroplasty (CDA) in 2-level hybrid surgery (HS) is affected by adjacent fusion invivo compared with 1-level CDA alone. A total of 180 patients undergoing either a 1-level CDA or contiguous 2-level HS were retrospectively reviewed. The clinical and radiographic outcomes were collected preoperatively and at routine postoperative intervals of 1 week, 3, 6, and 12 months, and at the last follow-up. The initial and postoperative radiographs were compared to determine the incidence and degree of ABL. ABL was identified in 68.7% of CDA cases (37.9% mild, 34.8% moderate, and 27.3% severe) and 44.0% of HS cases (54.1% mild, 27.0% moderate, and 18.9% severe). Sex, age, bone mineral density, operation time, blood loss, postoperative alignment, and range of movement at the arthroplasty segment were not related to the incidence of ABL. According to the logistic regression analysis results, ABL showed a significant correlation with the surgery type and body mass index. However, there was no significant difference in the incidence and degree of ABL with or without an adjacent fusion level. Compared with preoperative values, clinical outcome scores significantly improved after surgery in both the HS and CDA groups. No definite clinical effect associated with ABL was found. ABL was common in both CDA and HS. Although HS had a lower incidence rate and degree than did CDA, the fusion location in HS did not affect the ABL of adjacent CDA.

Headache Relief Is Maintained 7 Years After Anterior Cervical Spine Surgery: Post Hoc Analysis From a Multicenter Randomized Clinical Trial and Cervicogenic Headache Hypothesis.

ObjectiveTo evaluate whether anterior cervical spine surgery offers sustained (7 years) relief in patients with cervicogenic headaches (CGHs), and evaluate the difference between cervical disc arthroplasty (CDA) and anterior cervical discectomy and fusion (ACDF) for 1 and 2-level surgeries from a multicenter randomized clinical trial. MethodsA post hoc analysis was performed of 575 patients who underwent one or 2-level CDA or ACDF for symptomatic cervical spondylosis as part of a prospective randomized clinical trial. Assessment of pain and functional outcome was done with the Neck Disability Index (NDI) in the trial. We used the NDI headache component to assess headache outcome. ResultsFor both 1- and 2-level CDA and ACDF groups, there was significant headache improvement from preoperative baseline out to 7 years (p < 0.0001). For 1-level surgeries, headache improvement was similar for both groups at the 7-year point. For 2-level treatment, CDA patients had significantly improved headache scores versus ACDF patients at the 7-year point (p = 0.016). ConclusionThe headache improvement noted at early follow-up was sustained over the long-term period with ACDF and CDA populations. In the case of 2-level operations, CDA patients demonstrated significantly greater benefit compared to ACDF patients over the long-term. Sinuvertebral nerve irritation at the unco-vasculo-radicular junction and anterior dura may be the cause of CGH. Therefore, it is possible that improved cervical kinematics and preservation of range of motion at adjacent uncovertebral joints in CDA may contribute to the observed difference between the groups.