Cervical Degenerative Disc Disease Research Articles

Comparison of Different Hybrid Techniques for the Treatment of Multilevel Cervical Degenerative Disc Disease–Analysis of Prospectively Collected Clinical, Radiologic, and Psychological Parameters

Conventional surgical treatment of multilevel cervical disc disease is based on anterior cervical discectomy and fusion (ACDF). However, fusion alters the biomechanics of the spine, potentially resulting in accelerated adjacent segment degeneration. To improve clinical outcomes, hybrid surgery, combining cervical disc arthroplasty with fusion, has been developed. Cervical total disc replacement (TDR) has been shown to keep the motion of adjacent segment, and a dynamic cervical implant (DCI) was shown to provide cervical dynamic stability under nonfusion. However, curative and unwanted side effects of the new therapy options TDR and DCI for treating multilevel cervical degenerative disc disease are still unknown. This analysis is based on 88 patients treated for multilevel cervical degenerative disc disease with ACDF only (56 patients), DCI hybrid (17 patients), and TDR hybrid (15 patients) between June 2008 and November 2015. The mean follow-up was 19.5 months. Visual analog scale (VAS), Neck Disability Index, and quality-of-life measurements were assessed via questionnaires. The VAS scores decreased significantly in all 3 groups (P < 0.001), but the TDR group showed the greatest reduction in VAS score compared with ACDF and DCI (both P < 0.05). The overall range of motion (ROM) and the segmental ROM at the treated levels showed significant decreases in all 3 groups. Although there was no difference in the overall ROM at final follow-up among the operatively treated groups, the ROM of the treated segment was lowest in the ACDF group (P= 0.002). In terms of heterotopic ossification, patients undergoing TDR showed the best prognosis. These results indicate that both TDR hybrid and DCI hybrid are effective and safe procedures for the treatment of multilevel degenerative disc disease. However, there is no definitive evidence that DCI or TDR arthroplasty lead to better intermediate-term results than ACDF over an average observation time of 19.5 months.

Adjacent segment biomechanical changes after one- or two-level anterior cervical discectomy and fusion using either a zero-profile device or cage plus plate: A finite element analysis

Anterior cervical discectomy and fusion (ACDF) is a well-established surgical treatment for patients with symptomatic cervical degenerative disc disease, while the biomechanical changes of adjacent segments after ACDF using either a zero-profile device or cage plus plate remain uncertain. The present study is to compare adjacent segment biomechanical changes after one- or two-level ACDF using either a zero-profile device or cage plus plate.A three-dimensional finite element (FE) intact cervical model (C2–C7) was constructed and validated. In the one-level surgery model, either a zero-profile device or cage plus plate was implanted at the C5–C6 segment of the model; while in the two-level surgery model, the prostheses were implanted at the C4–C5 and C5–C6 segments of the model. A pure moment of 1.0 Nm combined with a follower load of 73.6 N were imposed on C2 to determine the flexion-extension, lateral bending, and axial rotation of different segments. The segmental range of motion (ROM) and maximum value of the intradiscal pressure of the surgery models were determined and compared with those of the intact model.In both one- and two-level ACDF models, the ROM of the fused segments was sacrificed, while loss of ROM at the fused segments was greater in cage plus plate models than in zero-profile device models because of structural differences of the implanted devices. However, the ROM and intradiscal pressure were increased at the C4–C5 and C6–C7 segments in the one-level model of ACDF using either a zero-profile device or cage plus plate, the ROM and intradiscal pressure were also increased at the C3–C4 and C6–C7 segments in the two-level surgery models.In conclusion, decreased ROM was observed at the fused segments, while increased ROM and intradiscal pressure were observed at the adjacent segments of the fused segments in ACDF, regardless of whether zero-profile devices or cage plus plate was used. Moreover, loss of ROM at the fused segments was greater in cage plus plate models than in zero-profile device models.

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

This study was a meta-analysis of published randomized controlled trials (RCTs). We investigated the mid-term to long-term outcomes of cervical disk arthroplasty (CDA) versus anterior cervical diskectomy and fusion (ACDF) for the surgical treatment of symptomatic cervical disk degenerative disease. ACDF has been widely performed for the surgical treatment of symptomatic cervical disk degenerative disease. However, the loss of motion at the operated level has been hypothesized to accelerate adjacent-level disk degeneration. CDA was designed to preserve motion segments and decrease the risk/rate of adjacent segment degeneration. However, it is still uncertain whether mid-term to long-term outcomes after CDA is more effective and safer than those observed after ACDF. Two independent reviewers conducted a search of PubMed, Embase, and the Cochrane Library databases for RCTs with a minimum of 48 months of follow-up. For dichotomous variables, the risk ratio and 95% confidence intervals were calculated. For continuous variables, the standardized mean difference and 95% confidence intervals were calculated. Eleven RCTs, finally, were included. The rate of neurological success in the CDA group was not significantly different from that in the ACDF group. The pooled results show that patients who underwent CDA had a significantly greater improvement in Neck Disability Index (NDI) and Short Form 36 Health Survey physical component (SF-36 HSPC) than did those who underwent ACDF. No significant difference was found when comparing the neck and arm pain scores between the CDA and ACDF groups. The overall rate of secondary surgical procedures was significantly lower in patients who underwent CDA than in those who underwent ACDF. We observed similar overall rates of adverse events and adjacent segment degeneration when comparing the CDA group with the ACDF group. This meta-analysis provides evidence suggesting that CDA was superior to ACDF in terms of NDI score, SF-36 HSPC score, and low rate of secondary surgical procedures. Furthermore, no significant differences existed between the CDA group and the ACDF group in the neck pain visual analog scale score, arm pain visual analog scale score, the rate of neurological success, adjacent segment degeneration, and adverse events. Level 1.

Two-Year Clinical and Radiological Outcomes in Patients With Diabetes Undergoing Single-Level Anterior Cervical Discectomy and Fusion.

Study Design:Secondary analysis of data from the multicenter, randomized, parallel-controlled Food and Drug Administration (FDA) investigational device exemption study.Objective:Studies on outcomes following anterior cervical discectomy and fusion (ACDF) in individuals with diabetes are scarce. We compared 24-month radiological and clinical outcomes in individuals with and without diabetes undergoing single-level ACDF with either i-FACTOR or local autologous bone.Methods:Between 2006 and 2013, 319 individuals with single-level degenerative disc disease (DDD) and no previous fusion at the index level underwent ACDF. The presence of diabetes determined the 2 cohorts. Data collected included radiological fusion evaluation, neurological outcomes, Neck Disability Index (NDI), Visual Analog Scale (VAS) scores, and the 36-Item Short Form Survey Version 2 (SF-36v2) Physical and Mental component summary scores.Results:There were 35 individuals with diabetes (11.1%; average body mass index [BMI] = 32.99 kg/m2; SD = 5.72) and 284 without (average BMI = 28.32 kg/m2; SD = 5.67). The number of nondiabetic smokers was significantly higher than diabetic smokers: 73 (25.70%) and 3 (8.57%), respectively. Preoperative scores of NDI, VAS arm pain, and SF-36v2 were similar between the diabetic and nondiabetic participants at baseline; however, VAS neck pain differed significantly between the cohorts at baseline (P = .0089). Maximum improvement for NDI, VAS neck and arm pain, and SF-36v2 PCS and MCS scores was seen at 6 months in both cohorts and remained stable until 24 months.Conclusions:ACDF is effective for cervical radiculopathy in patients with diabetes. Diabetes is not a contraindication for patients requiring single-level surgery for cervical DDD.

Comparison of peek cage vs bone graft only in anterior cervical discectomy and fusion

Anterior Cervical Discectomy and Fusion (ACDF) is the most frequently performed surgical treatment for several cervical spinal diseases. Including herniated disc, trauma and degenerative diseases [5, 8]. We have collected data of 31 patients admitted and operated between November 2017 to June 2019 having degenerative cervical disc disease who underwent ACDF reinforced with anterior cervical plate [11, 20]. All ACDF operations were performed using Smith-Robinson anteromedial approach using a surgical microscope [5, 16]. Approach Philadelphia collar were applied for 1 month post operatively. In our study we observed that ACDF achieves favourable radiologic results. The whole study data shows that there is a significant change in alignment of affected cervical spine after performing ACDF. Surgery related complications were not observed. No graft malposition, migration or mechanical failure of instruments. Objective: To evaluate radiologic result of anterior cervical discectomy and fusion. Methods: Retrospective review of clinical and radiological data of 31 patients. Cobb’s angle, C1-C2 angle, C2-C7 angle, Vertebral height were measured and followed.

Cervical stand-alone PEEK cage versus anchored cage with screws in single-level anterior cervical discectomy and fusion: A prospective cohort study

Background: Anterior cervical discectomy and fusion (ACDF) is a gold standard procedure for surgical management of symptomatic cervical degenerative disc disease. Traditionally, iliac crest bone graft was used as a strut graft to fill the disc space after discectomy. However, several complications have been observed, including donor site hematoma, infection, and pain. A cage can be used as an alternative, but cage dislodgement can be a devastating complication. Some surgeons advocate plate application to augment the cage construct, but the incidence of dysphagia is much higher with longer operative times. An anchored cage with screws could reduce postoperative dysphagia and simultaneously fix the cage. This study compared the clinical and radiographic outcomes of stand-alone polyetheretherketone (PEEK) cage with the anchored cage with screws for single-level ACDF. Methods: This prospective study was conducted in 50 patients who underwent single-level ACDF for cervical degeneration, with radiculopathy or myelopathy, from January, 2012, to January, 2014, at a single institution. Follow-up was 2 yr. Twenty-one patients were allocated to the stand-alone cage group (group 1) and 29 to the anchored cage with screws group (group 2). The Neck Disability Index (NDI), Visual Analogue Scale (VAS) of the arm and neck, radiographic segmental cervical angle (CA), and disc height assessments were done preoperatively, at 6 mo, and at 2 yr postoperatively. Results: Clinical outcomes showed improvement in both groups. The change between final follow-up (24 mo) and 6 mo postoperative CA (P=0.01) and disc height (P=0.02) showed statistically better outcomes for the anchored cage group (group 2) than the stand-alone cage group (group 1). The VAS showed significant pain improvement in the stand-alone group (group 1) than in the anchored cage with screws group (group 2) at 2 yr. The NDI difference was highly significant (P=0.001) preoperatively and at 6 mo postoperatively in favor of group 2, but this did not persist at 2-year follow-up. Conclusions: For one-level ACDF, the anchored cage with screws has some advantage compared to the stand-alone PEEK cage in avoiding dysphagia and restoring disc space height and cervical lordosis. We suggest the anchored spacer may be a good substitute for the stand-alone cage in one-level ACDF. Level of Evidence: Level II

Single level anterior cervical discectomy and fusion versus dynamic cervical implant: clinical and radiological outcome

BackgroundAlthough anterior cervical discectomy and fusion (ACDF) is considered a gold standard approach for surgical management of cervical disc herniation syndromes, the use of dynamic cervical implant (DCI) provided a novel technique that aims at reconstruction of the anterior column while facilitating controlled neck motion and reducing stress across the facet joints.Aim of the workThe objective of this study is to evaluate the clinical and radiological outcome of the DCI surgery in comparison to that achieved with ACDF using a conventional polyethylethylketone (PEEK) cage.Materials and methodsThis is a retrospective comparative study of 30 patients, with single level cervical degenerative disc disease (DDD), managed by the authors, either by DCI (n = 15) or ACDF (n = 15). Clinical and radiologic outcomes were assessed at 1, 3, and 12 months postoperatively. Clinical scoring systems included the Visual Analog Scale for Neck (VAS-N) and Arm (VAS-A), the Neck Disability Index score (NDI), as well as the evaluation of incidence of complications and neurological deterioration postoperatively. Radiographic evaluation included the assessment of postoperative cervical implant fusion, as well as evaluating the incidence of implant migration. Study duration was for two years from October 2016 to October 2018.ResultsBoth the ACDF and DCI groups showed significant clinical improvement at 12 months postoperatively regarding the clinical outcome including VAS-A, VAS-N, and NDI values (P = 0.001), while there was no significant difference on comparing between the two groups as regard the VAS-N, the VAS-A, and the NDI at 1,3 and 12 months after surgery. The ACDF group however showed better rate of implant fusion at 12 months postoperatively in contrast to the DCI group (80% and 26,7%, respectively) also, the ACDF group showed a lower rate of implant subsidence at 12 months after surgery (P = 0.002). Besides, the incidence of implant migration was relatively high in the DCI group (20%).ConclusionThe clinical results for DCI arthroplasty for the management of single-level cervical DDD are equivalent to those for ACDF; however, though providing an immediate dynamic stability, DCI is associated with a low fusion rate, higher rates of implant subsidence, and relatively high implant migration rate. Larger series and further studies should be considered with longer follow-up periods giving special attention to these issues.

Comparison of 2-year follow-up results of the hybrid surgery using Mobi-C combined with ROI-C and anterior cervical discectomy and fusion for the treatment of contiguous two-level cervical degenerative disc diseases

Although the Mobi-C artificial disc and the ROI-C cervical cage have been widely used in the treatment of cervical degenerative disc diseases (CDDD), few reports addressed the features of combined application of both devices. This study is aimed at comparing the clinical and radiological outcomes of treating contiguous two-level CDDD using Mobi-C and ROI-C combined in a hybrid surgery (HS) with anterior cervical discectomy and fusion (ACDF) using ROI-C. We reviewed ninety-one patients who underwent HS (n = 48) or ACDF (n = 43) surgery for symptomatic contiguous two-level CDDD. >2 years’ clinical and radiological outcomes were reviewed and evaluated retrospectively. At the last follow-up, significant improvement in the mean VAS, JOA, and NDI scores was found both in the HS and ACDF groups (p < 0.05), while the differences between groups were not significant (p > 0.05). The global range of motion (ROM) in the HS group was significantly larger than that in the ACDF group (p < 0.05). The local lordosis improved significantly after surgery in all patients (p < 0.05). Bone resorption and heterotopic ossification (HO) were found after surgery. The result showed that, for the selected patients, HS may provide an alternative approach for the treatment of contiguous two-level CDDD. HS also offers the benefit of both greater global ROM and greater ROM at the Mobi-C index level. Some degree of bone resorption may be an integral component in the early stage of bony fusion in the cage index level. Further studies and long-term follow-up are still needed.

Biomechanical comparison of noncontiguous cervical disc arthroplasty and noncontiguous cervical discectomy and fusion in the treatment of noncontinuous cervical degenerative disc disease: a finite element analysis

BackgroundBiomechanical characteristics of noncontinuous ACDF and noncontinuous CDA in the treatment of noncontinuous cervical degenerative disc disease were still unclear. The aim of this research is to compare the differences between these two kinds of treatment methods and to verify the effectiveness of Prodisc-C in noncontinuous CDA.MethodsEight FEMs of the cervical spine (C2–C7) were built based on CT images of 8 mild CDDD volunteers. In the arthroplasty group, we inserted Prodisc-C at C3/4 and C5/6. In the fusion group, CoRoent® Contour and NuVasive® Helix ACP were implanted at C3/4 and C5/6. Initial loads of 75 N were used to simulate the head weight and muscle forces. The application of 1.0 N m moment on the top on the C2 vertebra was used to create motion in all directions. Statistical analyses were performed using STATA version 14.0 (Stata Corp LP, College Station, Texas, USA). Statistical significance was set at P < 0.05.ResultsThe IDPs in C2/3 (P < 0.001, P = 0.005, P < 0.001, P < 0.001), C4/5 (P < 0.001), and C6/7 (P < 0.001) of the intact group were significantly less than that in the fusion group in flexion, extension, lateral bending, and axial rotation, respectively. In addition, the IDPs in C2/3 (P < 0.001, P = 0.001, P < 0.001, P < 0.001), C4/5 (P < 0.001), and C6/7 (P < 0.001) of the arthroplasty group were significantly less than that in the fusion group in flexion, extension, lateral bending, and axial rotation, respectively. Contact forces of facet joints in C2/3 (P = 0.010) in the arthroplasty group was significantly less than that in the intact group. Contact forces of facet joints in C2/3 (P < 0.001), C4/5 (P < 0.001), and C6/7 (P < 0.001) in the arthroplasty group was significantly less than that in the fusion group. Contact forces of facet joints in C2/3 (P < 0.001), C4/5 (P < 0.001), and C6/7 (P < 0.001) in the intact group were significantly less than that in the fusion group.ConclusionsNoncontinuous CDA could preserve IDP and facet joint forces at the adjacent and intermediate levels to maintain the kinematics of cervical spine near preoperative values. However, noncontinuous ACDF would increase degenerative risks at adjacent and intermediate levels. In addition, the application of Prodisc-C in noncontinuous CAD may have more advantages than that of Prestige LP.

Stand-alone polyetheretherketone cages for anterior cervical discectomy and fusion for successive four-level degenerative disc disease without plate fixation.

Background:Anterior cervical discectomy with fusion became the most frequently performed technique for the treatment of symptoms related to cervical disc prolapse. Multilevel anterior cervical discectomy has been combined with anterior cervical plate application to help maintain the cervical lordosis and enhance fusion. This was associated with more soft-tissue separation and retraction with increased incidence of surgically related complications and postoperative dysphagia.Aim of the Study:The aim of this study is to evaluate the safety and efficacy of the stand-alone cervical polyetheretherketone (PEEK) cages in four-level discectomy and to determine if it is possible to avoid anterior plate fixation and to achieve satisfactory outcomes.Methodology:This is a retrospective study which was performed between June 2011 and December 2018 at one institute. The clinical and radiological data were collected from patients who underwent successive four-level anterior cervical discectomy and fusion with PEEK cages for degenerative cervical disc disease without plate fixation.Results:This study included 66 patients, 35 males and 31 females. The follow-up period was 24 months. Mean Japanese Orthopedic Association scores were 13.3 ± 1.41 preoperative and 15.9 ± 0.86 postoperative (P = 0.046). The cervical curvature index “Ishihara” (ICI) was 9.9 ± 5.90 preoperative and the mean of ICI was 10.5 ± 6.65 postoperative, which is insignificant, P = 0.7). The lordotic curvature according to these results was preserved till the end of the year and half of the follow-up period postoperative.Conclusion:Consecutive four-level anterior discectomy with PEEK cage interbody fusion without plate and screw is a safe and effective procedure in the absence of instability, and it may be a reliable alternative for the treatment of multilevel cervical disc.

The safety and efficacy of hybrid surgery for multilevel cervical degenerative disc disease versus anterior cervical discectomy and fusion or cervical disc arthroplasty: a systematic review and meta-analysis.

Multilevel cervical degenerative disc disease (CDDD) can be treated surgically with anterior cervical discectomy and fusion (ACDF), cervical disc arthroplasty (CDA), or a hybrid surgery (HS) of the two in which both procedures are used at different vertebral levels. A systematic review and meta-analysis was performed to compare the clinical and radiographical outcomes of HS against ACDF or CDA alone. Three electronic databases were searched for articles published before December 2018. The literature was searched and assessed by independent reviewers according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. Eight papers were identified as eligible with a total of 424 patients. Post-operative C2-C7 range of motion (ROM) was significantly greater after HS than ACDF (p = 0.004; mean difference (MD) 6.14°). The ROM of the superior adjacent segment was significantly lower after HS than ACDF (p < 0.0001; MD - 2.87°) as was the ROM of the inferior adjacent segment (p = 0.0005; MD - 3.11°). HS patients' return to work was shorter than those who underwent ACDF (p < 0.00001; MD - 32.01 days) and CDA (p < 0.00001; MD - 32.92 days). There were no statistically significant differences in functional outcomes following CDA compared with HS. There was no significant difference in operation time, intra-operative blood loss, or post-operative complications between any of the procedures. The number of included studies was small, the heterogeneity between them was substantial, and the quality of evidence was very low. Large randomised controlled trials are required to provide strong evidence that would enable recommendation of one intervention over another.

Comparison of M6-C and Mobi-C cervical total disc replacement for cervical degenerative disc disease in adults.

Cervical total disc replacement (CTDR) is complicated by adjacent segment degeneration (ASD). Since non-physiological spine kinematics after CTDR was postulated to cause ASD, M6-C prosthesis has been developed to better replicate the natural kinematics of the intervertebral disc. This retrospective cohort study aims to compare the short-term outcomes between patients receiving either the M6-C or Mobi-C prostheses. Patients who had refractory radiculopathy and/or myelopathy secondary to cervical degenerative disc disease and underwent CTDR between March 2004 and April 2017 were included. All CTDRs were performed by a single surgeon at a single institution. Self-reported clinical outcomes and radiological parameters were evaluated at baseline and final follow-up between March 2004 and April 2018. Sixty-two patients with greater than 1-year follow-up or who developed HO within 12 months of surgery, were included in the study. The mean radiological follow-up was 29.0 months (3-84 months), which includes 7 patients with less than 12 months follow-up who also developed HO. The changes in clinical and radiological measures were comparable between M6-C and Mobi-C prostheses. Thirty-seven out of 52 spinal segments (71.2%) and 10 out of 16 spinal segments (62.5%) developed HO in M6-C and Mobi-C group respectively. There was no significant difference in the rate of HO between the two groups. No short-term differences were found in clinical or radiological outcomes between patients who received either the M6-C or Mobi-C prosthesis. Further randomized trials with a long-term follow-up period are warranted to determine the safety and efficacy of M6-C prosthesis.

The appropriate hybrid surgical strategy in three-level cervical degenerative disc disease: a finite element analysis

ObjectiveThe purpose of this FE study was to analyze the biomechanical characteristics of different HS strategies used in the treatment of three-level CDDD (one-level CDA and two-level ACDF).MethodsWe validated the FE model of an intact cervical spine established by transferring the data, collected by 3D CT scan, to the FE software ABAQUS and comparing these data with the data from published studies. Then, the FE model of hybrid surgery was reconstructed to analyze the range of motion (ROM), facet joint force, and stress distribution on an ultrahigh molecular weight polyethylene (UHMWPE) core.ResultsThe current cervical FE model was able to measure the biomechanical changes in a follow-up hybrid surgery simulation. The total ROM of the cervical HS models was substantially decreased compared with the total ROM of the intact group, and the M2 (C3/4 ACDF, C4/5 CDA, and C5/6 ACDF) model had the closest total ROM to the intact group, but the facet joint force adjacent to the treatment levels showed very little difference among them. The stress distribution showed noticeable similarity: two flanks were observed in the center core, but the inlay of M2 was more vulnerable.ConclusionsThrough the comparison of ROM, the facet joint force after CDA, and the stress distribution of the prosthesis, we find that M2 model has a better theoretical outcome, especially in preserving the maximum total ROM.

One-Level Versus 2-Level Treatment With Cervical Disc Arthroplasty or Fusion: Outcomes Up to 7 Years.

Anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) have been used to treat degenerative disc disease at single as well as multiple cervical levels. This study compares the safety and efficacy of 1-level versus 2-level CDA and ACDF. In total, 545 and 397 patients with degenerative disc disease were studied in 1-level and 2-level Food and Drug Administration (FDA)-approved clinical trials, respectively: CDA (n = 280 and 209), ACDF (n = 265 and 188). Data from these studies were used to compare 1- versus 2-level procedures: the propensity score method was used to adjust for potential confounding effects, and adjusted mean outcome safety and efficacy scores at 2 and 7 years postsurgery were compared between 1-level and 2-level procedures within treatment type. One-level and 2-level procedures had similar rates of improvement in overall success and patient-reported outcomes scores for both CDA and ACDF. There were no statistical differences in rates of implant-related adverse events (AEs) or serious implant-related AEs between 1-level and 2-level CDA. The 7-year rate of implant-related AEs was higher for 2-level than 1-level ACDF (27.7% vs 18.9%, P ≤ .036), though the rates of serious implant-related AEs between ACDF groups did not differ significantly. Secondary surgery rates were not statistically different between 1-level and 2-level procedures (CDA or ACDF) at the index or adjacent levels at 2 or 7 years. Grade IV heterotopic ossification at 7 years was reported in 4.6% of 1-level CDA patients and 8.6%/7.3% at the superior/inferior levels, respectively, of 2-level CDA patients. One- and 2-level CDA appear equally safe and effective in the treatment of cervical degenerative disc disease. Two-level ACDF appears to be as effective as 1-level ACDF but with a higher rate of some AEs at long-term follow-up. 2. clinicaltrials.gov: NCT00667459, NCT00642876, and NCT00637156.

Posterior foraminotomy versus anterior decompression and fusion in patients with cervical degenerative disc disease with radiculopathy: up to 5 years of outcome from the national Swedish Spine Register.

The long-term efficacy of posterior foraminotomy compared with anterior cervical decompression and fusion (ACDF) for the treatment of degenerative disc disease with radiculopathy has not been previously investigated in a population-based cohort. All patients in the national Swedish Spine Register (Swespine) from January 1, 2006, until November 15, 2017, with cervical degenerative disc disease and radiculopathy were assessed. Using propensity score matching, patients treated with posterior foraminotomy were compared with those undergoing ACDF. The primary outcome measure was the Neck Disability Index (NDI), a patient-reported outcome score ranging from 0% to 100%, with higher scores indicating greater disability. A minimal clinically important difference was defined as > 15%. Secondary outcomes were assessed with additional patient-reported outcome measures (PROMs). A total of 4368 patients (2136/2232 women/men) met the inclusion criteria. Posterior foraminotomy was performed in 647 patients, and 3721 patients underwent ACDF. After meticulous propensity score matching, 570 patients with a mean age of 54 years remained in each group. Both groups had substantial decreases in their NDI scores; however, after 5 years, the difference was not significant (2.3%, 95% CI -4.1% to 8.4%; p = 0.48) between the groups. There were no significant differences between the groups in EQ-5D or visual analog scale (VAS) for neck and arm scores. The secondary surgeries on the index level due to restenosis were more frequent in the foraminotomy group (6/100 patients vs 1/100), but on the adjacent segments there was no difference between groups (2/100). In patients with cervical degenerative disc disease and radiculopathy, both groups demonstrated clinical improvements at the 5-year follow-up that were comparable and did not achieve a clinically important difference from one another, even though the reoperation rate favored the ACDF group. This study design obtains population-based results, which are generalizable.

Long-Term Comparison of Health Care Utilization and Reoperation Rates in Patients Undergoing Cervical Disc Arthroplasty and Anterior Cervical Discectomy and Fusion for Cervical Degenerative Disc Disease

Thus study was a retrospective cohort analysis. Anterior cervical discectomy and fusion (ACDF) has been the gold-standard procedure for single-level degenerative disc disease (DDD). Recently, cervical disc arthroplasty (CDA) has become increasingly prevalent as an alternative intervention. To examine the long-term costs and reoperation rates associated with CDA and ACDF for the treatment of single-level DDD. In the present study, we performed a retrospective cohort analysis using the MarketScan database of patients who underwent either ACDF or CDA between 2007 and 2011 and had 5 years postsurgery follow-up. Outcomes related to the health care utilization, cost, and reoperation were analyzed after propensity score matching (PSM). Of 12,434 patients, 12,099 underwent ACDF and 335 CDA. Length of hospital stay and initial hospitalization cost was higher after ACDF compared with CDA. More patients undergoing CDA had early physical therapy compared with patients undergoing ACDF (CDA 30.15% vs. ACDF 22.39%; P= 0.0176). Five years after surgery, there was no significant difference in overall payments between patients undergoing ACDF and patients undergoing CDA. Reoperation rates were comparable at 5 years after the index procedure (CDA 8.06% vs. ACDF 9.25%; P= 0.5862). Patients who underwent ACDF showed decreased use of tramadol after surgery (15.09% before surgery vs. 9.55% after surgery; P < 0.0001). We found no difference in health care utilization between ACDF and CDA procedures for DDD 5 years after surgery. Also, there was no difference in reoperation rates during the study period. ACDF resulted in significant reduction in overall opioid use after versus before procedure.

P124. Cervical degenerative disc disease and subclinical discitis: cause or contaminant?

BACKGROUND CONTEXT Lumbar degenerative disc disease has been associated with culture positive disc space infection and P. acnes is the mostly commonly identified organism. PURPOSE This study aims to determine the prevalence of underlying infection in patients undergoing anterior cervical decompression and fusion (ACDF). STUDY DESIGN/SETTING Prospective Study. PATIENT SAMPLE A total of 96 patients. OUTCOME MEASURES Rate of disc Infection. METHODS After IRB approval, patients scheduled to undergo elective ACDF were prospectively enrolled. Samples of the longus colli muscle and disc tissues were obtained intraoperatively. Samples were homogenized, gram stained and cultured in both aerobic and anaerobic medium for 5 and 14 days, respectively. RESULTS Of the 96 patients, 41.6% were male with an average age of 53.8±10.9 years and BMI of 29.7±5.9. Control cultures of longus colli muscle were positive in 48 (50.0%) patients. Compared to the 20.8% of male patients in negative control (NC) patients, there were significantly more (62.5%) male patients in the positive control (PC) group (p CONCLUSIONS The 54% infection rate of cervical spine discs correlates with infection rate in the lumbar spine reported by many studies. Our control cultures of longus colli muscle show a strong association with the disc culture. The strong correlation between disc cultures and longus colli cultures suggest possible contiguous spread of infection. Our findings show that infection of the disc space is a possible cause of degenerative disc disease of the cervical spine. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

266. Angiotensin-II type-1 receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACEIs) display opposite fusion rates in cervical spine

BACKGROUND CONTEXT Approximately 132,000 patients per year undergo anterior cervical discectomy and fusion (ACDF) in the United States. Although the utilization of instrumentation and bone graft alternatives has enhanced fusion rates, pseudarthrosis remains a problem, with incidence rates up to 56%. Renin-angiotensin system (RAS) modulators are typically used to treat arterial hypertension, which affects 50-80% of spinal fusion patients. Recent evidence suggests an association between RAS blockers and bone metabolism, particularly in the context of bone healing. In addition, preclinical and clinical studies have suggested a potential correlation between the use of RAS blockers and reduced osteoporotic fracture risk. PURPOSE We aimed to determine whether there was a correlation between the use of antihypertensive medication, particularly angiotensin-II type-1 receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACEIs), and outcomes in anterior cervical discectomy and fusion (ACDF) surgery. STUDY DESIGN/SETTING Retrospective observational study. PATIENT SAMPLE Degenerative disc disease patients who underwent ACDF. OUTCOME MEASURES Spinal fusion status and neurological function (modified Japanese Orthopaedic Association [mJOA] and Nurick grading scales. METHODS A cohort of adult patients with symptomatic cervical degenerative disc disease who were operated upon using an allograft implant, and with a 1-year minimum follow-up was considered eligible. Information on demographic data, comorbidities (especially hypertension status), antihypertensive medication, neurological examination and fusion status were collected. Fusion criteria in static radiographs were increased opacification and bridging trabecular bone at the margins of the graft. In dynamic radiographs, fusion criteria were interspinous motion of RESULTS A total of 178 patients with cervical degenerative disc disease who underwent ACDF, with a median age of 53.7 (range 24-90) years, were included in the analysis. Median follow-up was 21.7 months. Out of the 82 hypertensive patients who were identified, 77 (93.9%) were taking antihypertensive drugs (28 [36.4%] received ARBs and 27 [35.1%] received ACEIs). The overall pooled fusion rate was 69.5%. Patients treated with ARBs exhibited a higher fusion rate compared to those who were untreated (88.9% vs 69.7%, respectively, p=.04). By contrast, patients treated with ACEIs displayed a lower fusion rate than untreated patients (45.8% vs 69.7%, respectively, p=.02). Comparisons between successful fusion and failed fusion groups identified treatment with ACEIs as risk factors for the development of pseudarthrosis. Treatment with ARBs displayed a trend towards being a favorable factor for fusion (RR=1.2, 95% CI 1.0, 1.5). In the multivariate nominal logistic analysis, ARB (p=.02) treatment remained an independent risk and beneficial factor, respectively, for fusion. CONCLUSIONS In our retrospective study of a cohort of ACDF patients, treatment with ARBs was associated with an increased fusion rate, while treatment with ACEIs identified as risk factor for failed fusion. Further preclinical and clinical studies are needed to verify the beneficial effects of ARBs and deleterious influence of ACEIs on spinal fusion. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

P128. The association of preoperative disc height with radiographic and clinical outcomes following ACDF

BACKGROUND CONTEXT Disc space collapse often occurs later in the natural course of cervical degenerative disc disease, and during anterior cervical discectomy and fusion (ACDF), restoration of disc space height and lordosis can assist with decompression and restoration of alignment. It is unclear if the amount of preoperative cervical disc space collapse correlates with outcomes following ACDF. PURPOSE The aim of the present study was to characterize preoperative disc space height in a sample of ACDF patients and to determine the association with postoperative clinical and radiographic outcomes following ACDF. STUDY DESIGN/SETTING Retrospective cohort study. PATIENT SAMPLE Analysis of consecutive patients who underwent a single-level ACDF between 2008-2015 for cervical radiculopathy and/or myelopathy, with more than 6 months of clinical and radiographic follow-up was conducted. Exclusion criteria were patients under 18 years of age at the time of surgery, previous cervical fusion or concomitant posterior cervical surgery, had postoperative follow up less than 6 months, or had an ACDF for cervical spine fracture, tumor, or infection. OUTCOME MEASURES Preoperative disc height was measured in terms of preoperative anterior vertebral distance (pAVD), mid-vertebral distance (pMVD), and posterior vertebral distance (pPVD). Sagittal parameters were also measured, and included change in C2-C7 lordosis, T1 angle, levels fused, sagittal vertical axis (SVA), fusion mass lordosis, proximal and distal adjacent segment lordosis. Visual Analog Scale (VAS) neck, VAS arm, and Neck Disability Index (NDI) scores were collected at each postoperative clinical visit. The rates of adjacent segment disease, reoperation, fusion, and subsidence (postoperative disc space collapse >2mm) were determined for the study period. METHODS Radiographs were reviewed preoperatively and immediately postoperatively, and at final follow up along with patient-reported outcomes. Bivariate and multivariate logistic regressions were subsequently used to compare clinical outcomes between disc height. Multivariate analyses controlled for differences in baseline patient characteristics. RESULTS A total of 120 patients were included. At final follow-up, pAVD was associated with increased lordosis, SVA and proximal lordosis. Additionally, pMVD was associated with increased postoperative SVA (p=0.025), and final SVA (p=0.011). Preoperative PVD was associated with decreased postoperative distal lordosis (p=0.037) and increased final SVA (p=0.032). Notably, greater pAVD was associated with greater final VAS arm scores (p=0.022), greater pMVD was associated with increased final VAS neck (p=0.037) and final VAS arm scores (p=0.040), and greater pPVD was associated with greater final VAS neck (p=0.031) and arm (p=0.023) scores. Greater AVD, MVD, and PVD were all associated with a decreased preoperative to postoperative difference in VAS neck (p-value range 0.034-0.04). CONCLUSIONS Increased anterior, middle and posterior preoperative disc height were all associated with increased final SVA, among other parameters. Patients with well-maintained preoperative disc heights had greater final VAS neck scores, VAS arm scores, and had less postoperative improvement in VAS neck scores compared to patients with preoperative collapsed discs. These results suggest that patients with preoperative cervical disc space collapse may have superior outcomes compared to patients with maintained cervical disc height, and future studies are needed to further explore these differences. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

119. Ten-year outcomes of one- and two-level cervical disc arthroplasty: results from a US multicenter study

BACKGROUND CONTEXT Short- and mid-term studies have shown the effectiveness of cervical disc arthroplasty (CDA) to treat cervical disc degeneration. Upon completion of the 7-year Mobi-C FDA study, follow-up continued on a subset of CDA patients in the FDA study. PURPOSE The purpose of this study is to report the 10-year outcomes of a multicenter experience with cervical arthroplasty for 1- and 2-level pathology. STUDY DESIGN/SETTING This was a prospective cohort study of patients treated with cervical disc replacement at one or two contiguous levels using the Mobi-C® Cervical Disc. PATIENT SAMPLE Following completion of the 7-year FDA post approval study, follow-up continued to 10 years for consenting patients at 9 high-enrolling centers. The primary inclusion criteria were cervical degenerative disc at one or two contiguous levels and no prior cervical operations. OUTCOME MEASURES Outcome measures included NDI, VAS neck and arm pain, patient satisfaction, secondary surgical procedures (removals, revisions, reoperations, or additional fixation) and adverse events. Radiographic end points included segmental and global range of motion, sagittal alignment, adjacent level degeneration (ALD) and heterotopic ossification (HO). Radiographic ALD was defined with the Kellgren-Lawrence scale. HO was classified by the system adapted from McAfee and Mehren. Independent radiologists (Medical Metrics, Inc., Houston, TX) conducted radiographic evaluations. METHODS From the original enrollment of 257 CDA patients at 9 sites, 231 patients were eligible for follow-up after 7 years. Ten-year follow-up was obtained from 187 patients (81% follow-up). The longest follow-up was 11.2 years. Radiographs were obtained from 170 patients at 10 years. There were no significant differences in preoperative characteristics between these patients and the original FDA cohort. RESULTS Ten years after CDA, patients continued to show significant improvement from baseline NDI, VAS neck and arm pain, and neurologic function. Outcomes at 10 years were improved from results at 7 years for NDI at one (14.2 vs 18.7; p=0.12) and two levels (15.6 vs 19.7; p=0.02). Comparable results were observed for neck and arm pain. These improvements were less than the MCID for NDI and pain. There were no significant differences in outcomes between 1- and 2-level CDA at 10 years. Segmental flexion-extension range of motion remained significantly higher (p 0.05). The incidence of clinically relevant HO at 10 years was not significantly different from the 7-year incidence for 1-level (30.7% vs 29.6%; p=0.88) or 2-level (41.7% vs 39.2%; p=0.70) CDA patients. Only 2 subsequent surgeries were reported after 7 years. One patient underwent supplemental fixation at the index level 9.5 years after CDA. The other case was ACDF at a nonadjacent level unrelated to the CDA. Total incidence of subsequent surgery after 10 years was 4.7% (12/257) at the index level and 3.5% (9/257) at an adjacent level. CONCLUSIONS At 10-years, both 1- and 2-level CDA demonstrate sustained improvement of NDI, pain scores, range of motion and sagittal alignment compared to baseline. Progression of ALD and HO from 7 to 10 years was minimal. Our results through 10 years demonstrate that CDA with Mobi-C continues to be a safe and effective surgical treatment for patients with 1- or 2-level cervical degenerative disc disease. FDA DEVICE/DRUG STATUS Unavailable from authors at time of publication.