Anterior Cervical Disc Replacement Research Articles

Using Machine Learning Algorithms to Predict Postoperative Anterior Bone Loss Following Anterior Cervical Disc Replacement.

Machine learning model. This study aimed to develop and validate a machine learning (ML) model to predict moderate-severe anterior bone loss (ABL) following anterior cervical disc replacement (ACDR). A retrospective review of patients undergoing ACDR or Hybrid surgery (HS) at a single center was performed. Patients diagnosed as C3-7 single- or multi-level cervical disc degenerative diseases (CDDD) with more than 2years of follow-up and complete pre- and postoperative radiological imaging were included. An ML-based algorithm was developed to predict moderate-severe ABL based on perioperative demographic, clinical, and radiographic parameters. Model performance was evaluated in terms of discrimination and overall performance. A total of 339 ACDR segments were included (61.65% female, mean age 45.65 ± 8.03years). During a follow-up period of 45.65 ± 8.03months, 103 (30.38%) segments developed moderate-severe ABL. The model demonstrated good discrimination and overall performance according to precision (moderate-severe ABL: 0.71 ± 0.07, none-mild ABL: 0.73 ± 0.08), recall (moderate-severe ABL: 0.69 ± 0.08, none-mild ABL: 0.75 ± 0.07), F1-score (moderate-severe ABL: 0.70 ± 0.08, none-mild ABL: 0.74 ± 0.07), and area under the curve (AUC) (0.74 ± 0.10). The most important predictive features were higher height change, higher post-segmental angle, and longer operation time. Utilizing a ML approach, this study successfully identified risk factors and accurately predicted the development of moderate-severe ABL following ACDR, demonstrating robust discrimination and overall performance. By overcoming the limitations of traditional statistical methods, ML can enhance discovery, clinical decision-making, and intraoperative techniques.

Artificial intelligence in predicting postoperative heterotopic ossification following anterior cervical disc replacement.

This study aimed to develop and validate a machine learning (ML) model to predict high-grade heterotopic ossification (HO) following Anterior cervical disc replacement (ACDR). Retrospective review of prospectively collected data of patients undergoing ACDR or hybrid surgery (HS) at a quaternary referral medical center was performed. Patients diagnosed as C3-7 single- or multi-level cervical disc degeneration disease with > 2 years of follow-up and complete pre- and postoperative radiological imaging were included. An ML-based algorithm was developed to predict high grade HO based on perioperative demographic, clinical, and radiographic parameters. Furthermore, model performance was evaluated according to discrimination and overall performance. In total, 339 ACDR segments were included (61.65% female, mean age 45.65 ± 8.03 years). Over 45.65 ± 8.03 months of follow-up, 48 (14.16%) segments developed high grade HO. The model demonstrated good discrimination and overall performance according to precision (High grade HO: 0.71 ± 0.01, none-low grade HO: 0.85 ± 0.02), recall (High grade HO: 0.68 ± 0.03, none-low grade HO: 0.87 ± 0.01), F1-score (High grade HO: 0.69 ± 0.02, none-low grade HO: 0.86 ± 0.01), and AUC (0.78 ± 0.08), with lower prosthesis‑endplate depth ratio, higher height change, male, and lower postoperative-shell ROM identified as the most important predictive features. Through an ML approach, the model identified risk factors and predicted development of high grade HO following ACDR with good discrimination and overall performance. By addressing the shortcomings of traditional statistics and adopting a new logical approach, ML techniques can support discovery, clinical decision-making, and intraoperative techniques better.

Are There Still Any Benefits to Drainage for Anterior Cervical Arthrodesis/Arthroplasty by Cervicotomy?

A retrospective single-center study between January 2019 and January 2023. The role and contribution of drainage in the anterior approach to the cervical spine (cervicotomy) is much debated, motivated primarily by the prevention of retropharyngeal hematoma, so are there still any benefits to drainage? The anterior approach to the cervical spine is a widespread and common procedure performed in almost all spine surgery departments for the replacement of cervical intervertebral discs and medullar or radicular decompression. The primary endpoint was the occurrence of symptomatic postoperative cervical hematoma. Four hundred thirty-one patients who had undergone cervical spine surgery by anterior cervicotomy for cervicarthrosis or cervical disc herniation (anterior cervical discectomy and fusion and anterior cervical disc replacement) were consecutively included. Patients were separated into 2 groups: (1) Group A, 140 patients (with postoperative drainage) and (2) Group B, 291 patients (without drainage). The mean follow-up was 2.8 months. The 2 groups were comparable on all criteria, but there was a predominance of arthroplasty ( P < 0.0001), use of anticoagulants/antiaggregants ( P < 0.0001) and a greater number of stages ( P < 0.0001) in group A. There were a total of 4/431 symptomatic postoperative hematomas (0.92%) in this study. Two hematomas occurred in group A (2/140, 1.4%) and 2 in group B (2/291, 0.68%; P < 0.0001). One patient in group A (0.71%) required surgical drainage for cavity hematoma revealed by marked dyspnea, swallowing, and neurological disorders. One case of hematoma diagnosed by dysphonia and neurological deficit was reported in group B (0.34%; P < 0.0001). The placement of a drain during anterior cervicotomy (anterior cervical discectomy and fusion/anterior cervical disc replacement) did not limit the occurrence of symptomatic postoperative hematoma.

Comparing outcomes between anterior cervical disc replacement (ACDR) and minimally invasive posterior cervical foraminotomy (MI-PCF) in the treatment of cervical radiculopathy

BACKGROUND CONTEXTAnterior cervical disc replacement (ACDR) and minimally invasive posterior cervical foraminotomy (MI-PCF) have emerged as two increasingly popular alternatives to anterior cervical discectomy and fusion (ACDF) for the management of cervical radiculopathy. Both techniques provide advantages of segmental motion preservation and lower rates of adjacent segment degeneration (ASD) compared to ACDF. PURPOSEThe purpose of this study was to analyze the clinical and functional outcomes of patients undergoing ACDR or MI-PCF for the treatment of unilateral cervical radiculopathy. STUDY DESIGN/SETTINGRetrospective Cohort Review. PATIENT SAMPLEA total of 152 patients were included (86 ACDR and 66 MI-PCF). OUTCOME MEASURES(1) Patient demographics; (2) perioperative data; (3) rates of complications and revisions; (5) visual analogue scale (VAS) and Neck Disability Index (NDI) scores. METHODSA retrospective cohort review was performed to identify all patients at a single institution between 2012-2020 who underwent 1- or 2- level ACDR or MI-PCF from C3-C7 with a minimum follow-up of 24 months. Patient demographics, perioperative data, postoperative complications, and revisions were analyzed. Patient reported outcome measures including VAS and NDI scores were compared. RESULTSThe ACDR group had a significantly greater mean operative time (99.8 minutes vs 79.2 minutes, p<.001), but comparable estimated blood loss and length of stay following surgical intervention (p=.899). The overall complication rate was significantly greater in the ACDR group than the MI-PCF group (24.4% vs 6.2%; p=.003) but was largely driven by approach-related dysphagia in 20.9% of ACDR patients. The MI-PCF group had significantly greater revision rates (13.6% vs 1.2%; p=.002) with an average time to revision of 20.7 months in the MI-PCF group compared to 40.3 months in the ACDR group. The ACDR cohort had significantly greater improvements in NDI scores at the final follow-up (25.0 vs 21.3, p<.001). ConclusionOur results suggest that ACDR offer clinically relevant advantages over MI-PCF in terms of long-term revision rates despite an increased approach-related risk of transient postoperative dysphagia. Additionally, patients in the ACDR cohort achieved greater mean improvements in NDI scores but these results may have limited clinical significance due to inability to reach minimally clinically important difference (MCID) thresholds.

Management outcomes of cervical radiculopathy with conservative treatment, anterior cervical discectomy fusion (ACDF), and anterior cervical disc replacement (ACDR)—Retrospective single center matched cohort study

Abstract Background: Degenerative cervical radiculopathy results from nerve root compression in the cervical neural foramina, often due to a herniated disc, osteophyte, or facetal/ligamentum flavum hypertrophy. Typically, 80% of patients show improvement within the initial 12 weeks through nonoperative measures, with surgical intervention considered for non-responders. This study aimed to compare clinical and radiological outcomes in cervical radiculopathy patients undergoing prolonged conservative care, anterior cervical discectomy and fusion (ACDF), or anterior cervical disc replacement (ACDR) after a 1‐year follow‐up. Materials and Methods: Our study was a retrospective single‐center study involving 780 cervical radiculopathy patients from January 2012 to December 2021. About 80.12% found relief with conservative management within 12 weeks. Remaining 155 patients were offered surgery, with 73 opting for continued conservative care, and 82 undergoing surgery (55 with ACDF and 27 with ACDR). Evaluation was done using visual analogue scale (VAS), Neck Disability Index (NDI), and radiographic parameters. Results: The mean follow‐up was 11.58 ± 6.7 months. ACDR group: Mean age 43.38 ± 8.56, VAS 7.81 ± 1.04 preoperatively, improved significantly to 2.07 ± 1.34 (P &lt; 0.05) at 1‐year follow‐up. ACDF group: Mean age 44.85 ± 10.65, VAS 8.22 ± 1.21 preoperatively, improved significantly to 2.09 ± 1.01 (P &lt; 0.05) at 1‐year follow‐up. Conservative group: Mean age 45.04 ± 11.19, VAS 7.77 ± 1.86 preoperatively, improved significantly to 2.08 ± 1.40 (P &lt; 0.05) at 1‐year follow‐up. Radiographic parameters significantly improved in all groups at 1‐year follow‐up (P &lt; 0.05). Range of motion (ROM) changes varied across groups. Miyazaki’s grading and Kim’s score showed comparable results. Conclusion: Comparable clinical and radiological outcomes were observed among conservative, ACDF, and ACDR approaches. ACDR approach demonstrated a better NDI score outcome. Neck ROM was better maintained or improved in the ACDR approach, decreased in ACDF, and remained almost similar in the conservative group.

Changes in the centre of rotation and the anterior bone loss of the vertebral body in Mobi-C artificial disc replacement segments after cervical hybrid surgery: a retrospective study.

To examine the short-term efficacy and imaging results of using the Mobi-C in cervical hybrid surgery on 2-level cervical spondylolisthesis. To observe post-operative changes in the flexion-extension centre of rotation (FE-COR) and anterior bone loss (ABL) of the anterior cervical disc replacement (ACDR) segment. Forty-two patients (20 males and 22 females, aged 42‒67years) who underwent cervical hybrid surgery were retrospectively analysed. Their ACDR segment used Mobi-C, and the fusion segment used ROI-C, with a follow-up of 25‒42months (31.1 ± 4.8months). The modified Japanese Orthopaedic Association (mJOA) score, Neck Disability Index (NDI), and visual analogue scale (VAS) were used to assess clinical outcomes. Pre-operative, 6-month post-operative, and final follow-up radiographs were collected to compare total cervical spine curvature (C2-C7), curvature of the operated segments, range of motion (ROM) in the total cervical spine, operated segmental ROM, ACDR segmental ROM, and operated adjacent segmental ROM. The height of the superior articular process (HSAP), the orientation of zygapophyseal joint spaces (OZJS), and the length of the superior articular surface (LSAS) were measured. The FE-COR of the ACDR segment was measured using the mid-plumb line method. The translation distance of the Mobi-C was measured. The degree of disc degeneration in the adjacent segment, bony fusion of the ACDF segment, and ABL of the upper and lower vertebra of the ACDR segment were observed. In our group, all patients have shown improvements in their postoperative mJOA, NDI, and VAS scores. Overall cervical ROM and surgical segmental ROM decreased (P < 0.05). However, there was no significant decrease in ACDR segmental ROM and upper or lower adjacent segmental ROM compared with pre-operatively (P > 0.05). For FE-COR-X, only the last follow-up compared with pre-surgery showed statistical significance (46.74 ± 7.71% vs. 50.74 ± 6.92%, P < 0.05). For FE-COR-Y, the change was statistically significant at both 6months post-operation and the final follow-up compared to pre-operation (45.37% ± 21.11% vs. 33.82% ± 10.87%, 45. 37% ± 21.11% vs. 27.48% ± 13.58%, P < 0.05). No significant difference in the Mobi-C translation distance was observed (P > 0.05). Moreover, the difference in HSAP was not statistically significant at each node (P > 0.05). The OZJS and LSAS were significantly different at the final follow-up compared to the pre-operative period (P < 0.05). All the ACDF segments were observed in a stable condition at the final follow-up. Furthermore, 9 of the adjacent segments showed imaging ASD (9/82, 10.98%), and all were present at the last follow-up, of which 6 were mild, and 3 were moderate. Twenty of the 42 Mobi-C segments had no significant ABL (grade 0) 6months post-operatively (47.62%). Sixteen cases (38.10%) showed mild ABL (grade 1), and 6 cases (14.28%) showed moderate ABL (grade 2). No severe ABL occurred. The cervical hybrid surgery using Mobi-C artificial cervical discs can achieve satisfactory results. The Mobi-C segmental FE-COR-X shows a slow forward shift trend, and FE-COR-Y drops noticeably within 6months post-surgery before stabilizing. It's common to see mild to moderate ABL after cervical hybrid surgery using Mobi-C, and significant progression is unlikely in the short term. Furthermore, changes in the FE-COR after hybrid surgery in the Mobi-C segment might not affect clinical outcomes.

Anterior Cervical Discectomy and Fusion Versus Cervical Disc Replacement for a Workers' Compensation Population in an Ambulatory Surgical Center.

Retrospective Cohort. To evaluate patient-reported outcome measures (PROM) and minimal clinically important difference (MCID) achievement outcomes between anterior cervical discectomy and fusion (ACDF) and cervical disk replacement (CDR) in the Workers' Compensation (WC) population. No studies to our knowledge have compared PROMs and MCID attainment between ACDF and CDR among patients with WC insurance undergoing surgery in an outpatient ambulatory surgical center (ASC). WC insurance patients undergoing primary, single/double-level ACDF/CDR in an ASC were identified. Patients were divided into ACDF versus CDR. PROMs were collected at preoperative/6-week/12-week/6-month/1-year timepoints, including PROMIS-PF, SF-12 PCS/MCS, VAS neck/arm, and NDI. Seventy-nine patients were included, 51 ACDF/28 CDR. While operative time (56.4 vs. 54.4min), estimated blood loss (29.2 vs. 25.9mL), POD0 pain (4.9 vs. 3.8), and POD0 narcotic consumption (21.2 vs. 14.5 oral morphine equivalents) were higher in ACDF patients, none reached statistical significance ( P >0.050, all). One-year arthrodesis rate was 100.0% among ACDF recipients with available imaging (n=36). ACDF cohort improved from preoperative for PROMIS-PF from 12 weeks to 1 year, SF-12 PCS at 6 months, all timepoints for VAS neck/arm, and 12 weeks/6 months for NDI ( P ≤0.044, all). CDR cohort improved from preoperative for PROMIS-PF at 6 months, VAS neck/arm from 12 weeks to 1 year, and NDI at 12 weeks/6 months ( P ≤0.049, all). CDR cohort reported significantly lower VAS neck at 12 weeks/1 year and VAS arm at 12 weeks ( P ≤0.039, all). MCID achievement rates did not differ. While operative duration/estimated blood loss/acute postoperative pain/narcotic consumption were, on average, higher among ACDF recipients, these were not statistically significant, possibly due to the limited sample size. ACDF and CDR ASC patients generally demonstrated comparable arm pain/disability/physical function/mental health, though neck pain was significantly lower at multiple timepoints among CDR patients. Clinically meaningful PROM improvements were comparable. Larger, multicentered studies are required to confirm our results.

P69. Anterior cervical disc replacement (ACDR) versus minimally invasive posterior cervical foraminotomy (MI-PCF) in the treatment of cervical radiculopathy with 5-year followup

P69. Anterior cervical disc replacement (ACDR) versus minimally invasive posterior cervical foraminotomy (MI-PCF) in the treatment of cervical radiculopathy with 5-year followup

Trends in use, outcomes, and revision procedures of anterior cervical disc replacement in the United States: a premiere database analysis from 2006–2019

We sought to characterize trends in demographics, comorbidities, and postoperative complications among patients undergoing primary and revision cervical disc replacement (pCDR/rCDR) procedures. In this retrospective database study, the Premier Healthcare database was queried from 2006 to 2019. Annual proportions or medians were calculated for patient and hospital characteristics, comorbidities, and postoperative complications associated with CDR surgery. Trends were assessed using linear regression analyses with year of service as the sole predictor. A total of 16,178 pCDR and 758 rCDR cases were identified, with a median (IQR) age of 46 (39; 53) and 51 (43; 60) years among patients, respectively. The annual number of both procedures increased between 2006 and 2019, from 135 to 2220 for pCDR (p < 0.001), and from 17 to 49 for rCDR procedures (p < 0.001), with radiculopathy being the main indication for surgery in both groups. Mechanical failure was identified as a major indication for rCDR procedures with an increase over time (p = 0.002). Baseline patient comorbidity burden (p = 0.045) and complication rates (p < 0.001) showed an increase. For both procedures, an increase in outpatient surgeries and procedures performed in rural hospitals was seen (pCDR: p = 0.045; p = 0.006; rCDR: p = 0.028; p = 0.034). PCDR and rCDR procedures significantly increased from 2006 to 2019. At the same time, comorbidity burden and complication rates increased, while procedures were more often performed in an outpatient and rural setting. The identification of these trends can help guide future practice and lead to further areas of research.

Effect of facet joint distraction on the functional and radiological outcomes after anterior cervical disc replacement

ObjectiveThe purpose of this study is to explore: 1) whether the extent of facet joint distraction affects functional outcomes following single-level anterior cervical disc replacement (ACDR) for cervical spondylotic radiculopathy and 2) whether the extent of facet joint distraction correlates with the cervical sagittal parameters.MethodsWe performed a retrospective analysis on 70 patients who had undergone a single-level ACDR to treat cervical spondylotic radiculopathy between January 2014 and December 2018. Pre- and post-operative lateral cervical spine X-ray radiographs were collected to determine radiographic parameters, including C0-C2 angle, C2-C7 angle, C7 Slope (C7S), T1 Slope (T1S), C2–C7 sagittal vertical axis (SVA), C2-C7 range of motion (ROM), Segmental ROM, disc height (DH) and inter-facet distance (ID). And the extend of facet joint distraction was evaluated by the two indexes: degree of intervertebral distraction (DID) defined and degree of facet joint distraction (DFJD). The visual analog scale (VASneck) and the Neck Disability Index scores (NDI) were adopted to demonstrate functional outcomes. Patients with the functional outcome improvement below the average were set as the positive group in the receiver operating characteristic (ROC) curve analysis, to find an optimal cut-off value of extent of facet joint distraction.ResultsVASneck and NDI scores improved significantly from pre- to post-operation among the entire cohort, and DFJD had a statistically significant negative correlation with ΔVASneck (p < 0.001) and ΔNDI (p < 0.001). According to ROC curve analysis, the cut-off value of DFJD for differing the appropriate and excessive distraction groups was set at 29.16% (sensitivity = 70.73%, specificity = 67.86%). Between these two groups, the ΔT1S, ΔROM, ΔVASneck, and ΔNDI were significantly different (p < 0.05).ConclusionSingle-segment ACDR may improve the functional outcome of patients with cervical spondylotic radiculopathy. However, those whose DFJD was greater than 29.16% had worse VASneck and NDI scores, as well as a lower ΔT1S and a lower ΔROM.

CLINICAL RESULTS OF EVOLUTIONAL CHANGE OF PRACTICE FROM OPEN TO ENDOSCOPIC SURGERY FOR CERVICAL DISC HERNIATION AND FORAMINAL STENOSIS

Objective: Limited literature on the effect on clinical and radiological outcomes in cervical endoscopic spine surgery replacing a large percentage of open and microscopic minimally invasive surgery on outcomes in patients for cervical disc herniations and foraminal pathologies. Methods: Retrospective comparative cohort study of two periods of 2015 to 2017 (first generation) is compared to 2018–2020 (second generation) on surgical treatment of degenerative cervical spinal conditions for 132 spinal cases. Basic demographics, preoperative, post-operative 1 week, 3 months and final follow-up of patients’ clinical outcomes in terms of Visual Analog Scale Pain Score, Neck Disability Index, Japanese Orthopaedic Association Score and MacNab’s Criteria were evaluated. Results: In the first generation, 50 cases of cervical disc herniation and foraminal stenosis with 70% open anterior cervical discectomy fusion or disc replacement 30% of the cases underwent posterior cervical endoscopic procedures with complication rate of 2%. In the second generation, 82 cases of cervical disc herniation and foraminal stenosis with 7% open anterior cervical discectomy fusion or disc replacement 93% of the cases underwent posterior cervical endoscopic procedures with complication rate of 6%. Compared to preoperative score, motor, JOA, VAS and NDI scores all statistically significant improved within the individual cohort. Compared to the first generation, the second generation has statistically significant improved VAS of 0.326+/−0.146 at 3 months and 0.648+/−0.163 at final follow-up and statistically significant improved NDI of 2.81+/−1.15 at final follow-up, p &lt; 0.05. Conclusions: Generation change of increasing percentage of endoscopic surgeries and expansion of endoscopic spinal indications over open surgeries in degenerative spinal conditions and disc herniations are possible as a surgeon gets more experience with endoscopic spine surgery producing good clinical outcomes.

Anterior Cervical Discectomy and Fusion Versus Cervical Disc Replacement in Patients With Significant Cervical Spondylosis.

Retrospective cohort study. The aim was to compare clinical outcomes in patients with significant cervical spondylosis treated with cervical disc replacement (CDR) compared with anterior cervical discectomy and fusion (ACDF). As CDR utilization has increased over the past decade, recent studies have investigated the outcomes of CDR in patients with more significant spondylotic changes and demonstrated improved postoperative patient-reported outcomes (PROs). However, no prior study has investigated clinical outcomes of patients with significant spondylotic changes treated with CDR in comparison to ACDF. Patients who underwent 1-level or 2-level CDR or ACDF with significant cervical spondylosis, quantified using a validated grading scale, were identified, and prospectively collected data was retrospectively reviewed. The following PROs were analyzed: Neck Disability Index (NDI), visual analog scale-Neck, visual analog scale-Arm, and PROMIS Physical Function (PROMIS-PF) Computer Adaptive Test Score. Demographic, operative, and radiographic variables, and achievement of minimum clinically important difference (MCID) for each PRO were compared between the 2 groups. A total of 66 patients were included in the present study, of which 35 (53%) were treated with CDR and 31 (47%) with ACDF. The preoperative cervical spondylotic grade was similar between the 2 groups (1.8 vs. 2.2, P=0.27). At final follow-up, there was no significant difference in the absolute value for each PRO between the 2 groups (P>0.19) and both groups demonstrated significant improvement in each PRO compared with preoperative values (P<0.01). There was no significant difference in the percentage of patients achieving the MCID for each PRO when comparing CDR to ACDF (P>0.09). A similar percentage of patients with significant degenerative cervical spondylosis achieved the MCID across multiple PROs when treated with CDR or ACDF. Patients in both treatment groups demonstrated significant improvement in all PROs assessed when compared with preoperative values. Level III.

Postoperative Stroke after Anterior Cervical Discectomy and Fusion: A Clinical Case Report

Anterior cervical discectomy and fusion (ACDF) spine surgery has been performed extensively for the treatment of degenerative spine diseases with relatively low rates of complications. The reported incidence of postoperative cerebrovascular events associated with ACDF is only 0.13%, representing 1.51% of all complications. However, this complication is often highly disastrous and can lead to paralysis, and even death. In this study, a 42year-old male underwent anterior cervical discectomy and fusion (ACDF) at C34 and C45 levels through a right-sided approach. Three hours after the surgery, the patient suddenly developed left hemiplegia and facial palsy.. The patient was treated with aspirin and cerebromysin and fully recovered from motor and sensory deficits after 1 month.&#x0D; Keywords: Anterior cervical discectomy and fusion, postoperative stroke.&#x0D; References&#x0D; [1] P. S. Romano, D. R. Campa, J. A. Rainwater, Elective Cervical Discectomy in California: Postoperative in Hospital Complications And Their Risk Factors, Spine, Vol. 22, No. 1, 1997, pp. 2677-2692, https://doi.org/10.1097/00007632-199711150-00018.[2] B. S. Chozick, P. Watson, S. H. Greenblatt, Internal Carotid Artery Thrombosis After Cervical Corpectomy, Spine, Vol. 19, 1994, pp. 2230-2232, https://doi.org/10.1097/00007632-199410000-00020.[3] Y. C. Yeh, W. Z. Sun, C. P. Lin et al., Prolonged Retraction on The Normal Common Carotid Artery Induced Lethal Stroke After Cervical Spine Surgery, Spine, Vol. 29, No. 3, 2004, pp. 431-434, https://doi.org/10.1097/01.brs.0000141177.95850.b1.[4] J. E. Loret, P. Francois, C. Papagiannaki, Internal Sarotid Artery Dissection After Anterior Cervical Disc Replacement: First Case Report And Literature Review of Vascular Complications of The Approach, Eur J Orthop Surg Traumatol, Vol. 23, No. 1, 2013, pp. 107-110, https://doi.org/10.1007/s00590-013-1228-8.[5] M. Radhakrishnan, S. Bansal, G. S. Srihari, Perioperative Stroke Following Anterior Cervical Discectomy, Br J Neurosurg, Vol. 24, No. 1, 2010, pp. 592-594, https://doi.org/10.3109/02688691003711575.[6] Q. D. Yue, Carotid Artery Related Perioperative Stroke Following Anterior Cervical Spine Surgery: A Series of 3 Cases and Literature Review, Journal of Stroke And Cerebrovascular Diseases, Vol. 28, No. 2, 2019, pp. 458-463, https://doi.org/10.1016/j.jstrokecerebrovasdis.2018.10.024.[7] E. Matthew, Changes in Carotid Artery Blood Flow During Anterior Cervical Spine Surgery, Spine, Vol. 27, No. 2, 2002, pp. 152-155, https://doi.org/10.1177/2192568216688192.[8] D. C. Brooks, J. L. Schindler, Perioperative Stroke: Risk Assessment, Prevention and Treatment, Curr Treat Options Cardiovasc, Meds, Vol. 16, No. 1, 2014, pp. 282, https://doi.org/10.1007/s11936-013-0282-1.[9] E. C. Jauch, J. L. Saver, J. Adams, Guidelines for The Early Management of Patients with Acute Ischemic Stroke: A Guideline for Healthcare Professionals from The American Heart Association, American Stroke Association, Vol. 44, No. 1, 2013, pp. 870-947, https://doi.org/10.1161/STR.0b013e318284056a.[10] J. M. Cuellar, A. Petrizzo, R. Vaswani, Does Aspirin Administration Increase Perioperative Morbidity in Patients With Cardiac Stents Undergoing Spinal Surgery, Spine, Vol. 44, No. 1, 2015, pp. 629-635, https://doi.org/10.1097/BRS.0000000000000695.&#x0D; &#x0D;

161. Metal-on-metal vs metal-on-plastic artificial discs in 2-level anterior cervical disc replacement: a meta-analysis with follow up of 5 years or more

<h3>BACKGROUND CONTEXT</h3> Anterior cervical discectomy and fusion (ACDF) is a well-established procedure that has long been considered the standard treatment for degenerative disc disease (DDD). Despite positive clinical outcomes, accelerated rates of adjacent segment disease (ASD) in ACDF, especially in two-level surgery, has led spinal surgeons to increasingly use anterior cervical disc replacement (ACDR) as an alternative. However, long-term success may be limited by the properties inherent to the devices utilized. The use of metal-on-metal (MM) bearings in total joint replacement, for example, has been hypothesized to significantly decrease volumetric wear rates, but subsequent complications associated with metallosis have prompted joint surgeons toward using metal-on-plastic (MP) or ceramic implants more commonly. Furthermore, MP implants in total hip arthroplasty have been associated with superior clinical outcomes and durability when compared to MM implants. Although highlighted in joint arthroplasty studies, long-term outcomes between differing biomaterial composites in ACDR have not been thoroughly investigated. <h3>PURPOSE</h3> The purpose of this study was to evaluate the rates of ASD, reoperation rates, complications and patient reported clinical outcomes of MM vs MP artificial discs in two-level ACDR for the treatment of cervical DDD. <h3>STUDY DESIGN/SETTING</h3> Meta-analysis and systematic review. <h3>PATIENT SAMPLE</h3> A total of 980 patients (442 MM, 538 MP). <h3>OUTCOME MEASURES</h3> 1) Rate of ASD, 2) reoperation rate, 3) complications, 4) patient reported clinical outcomes (NDI, VAS-neck, VAS-arm). <h3>Methods</h3> A systematic search strategy of three electronic databases (PubMed, CINAHL Plus and SCOPUS) was conducted utilizing terms related to 2-level ACDR. All studies included were published in the past 5 years, had a sample size of >10 patients, and reported data on adjacent segment disease. Cadaver studies, non-English manuscripts and studies in which only single-level ACDR was investigated were excluded. A total of 7 studies were included in this analysis. Studies were analyzed for demographic data, clinical outcome scores (NDI, VAS-neck and VAS-arm), rates of ASD, complications and reoperation proportions. A random-effects model of meta-analysis was used for groups that were determined to be heterogenous and a fixed-effects model was utilized for groups that were not. An overlap of 95% confidence intervals suggests no statistically significant difference at the p<0.05 level. <h3>Results</h3> Seven studies were included with data on 980 patients (442 MM, 538 MP). The study population was 52.84% female, with a mean age of 48.01 years, and a mean follow-up of 85.66 months. The mean improvement in NDI was 34.42 (95% CI, 32.49-36.36) and 29.72 (95% CI, 27.15-32.29) for the MM and MP groups, respectively. The mean improvement in VAS-neck was 11.20 (95% CI, 10.69-11.70) and 8.78 (95% CI, 7.81-9.74) for the MM and MP groups, respectively. The mean improvement in VAS-arm was 10.73 (95% CI, 9.83-11.63) and 8.49 (95% CI, 7.59-9.39) for the MM and MP groups, respectively. Reoperation was needed in 1.36% (95% CI, 0.61-2.99) of patients who underwent ACDR with an MM implant compared to 5.33% (95% CI, 3.68-7.65) of patients with an MP implant. The MM cohort had a larger proportion of patients with ASD who underwent subsequent surgery at an adjacent level (7.89% MM vs 1.91% MP). Heterotopic ossification and dysphagia were the most common complications in both groups, and the incidence of each was significantly higher in the MP cohort. <h3>Conclusions</h3> Our present meta-analysis suggests that the use of MM artificial discs in 2-level ACDR results in superior clinical outcome scores with a lower complication profile and reoperation rate, but higher rates of ASD compared to MP discs after a follow-up period of 5 years or more. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Correlation study between postoperative Dysphagia and change in cervical alignment after anterior cervical spine surgery

Background and Aim: Understanding the correlation between the development of Dysphagia and change in the cervical alignment after cervical spine surgery in patients. Methods: From 2017 to 2020, 198 patients were treated with anterior cervical decompression and plate fixation where 12 months examination and study follow-ups are undertaken on 172 patients. Along with, the other 154 patients underwent anterior cervical disc replacement where 12 months extensive follow-ups were commenced on 98 patients. The questionnaire was distributed among 270 patients under 12 months follow-ups to investigate the onset and time of appearance of dysphagia, symptoms, relief, treatment plan and other health issues associated, if any. After getting the detailed feedback, all the patients were divided into the dysphagia group and the control group, to determine the excessive cervical lordosis change and other risk factors were associated with the dysphagia symptom or not. Results: The results showed that 12.8% of patients have postoperative dysphagia in anterior cervical discectomy in fusion group and 5.1% of patients have in cervical disc replacement group. According to the regression equation, the excessive change of C2-C7 angle significantly increases the incidence rate of postoperative dysphagia. It was also observed that, the incidence rate of postoperative dysphagia was significantly greater in patients whose C2-C7 angle change more than 5 degree compare to the patients has less than 5 degree C2-C7 angle. The assessed parameters like Sex, age, BMI, operation time, blood loss, surgery approach, revision ratio, the number of surgical segments, the highest surgical segment, and C3 segment doesn’t affect the occurrence of dysphagia. Conclusions: Development of Dysphagia symptoms are highly prevalent comorbidities after cervical spine surgery in the patients. The change in the Cervical lordosis importantly influencing promoting the occurrence of dysphagia after anterior cervical spine surgery.

Risk Factors of Extended Hospital Stay After One-Level Anterior Cervical Discectomy Fusion or Disc Replacement: Results from 1004 Patients in Food and Drug Administration Trials

Extended length of stay (LOS) after surgery is costly to the health care system and can be distressing to the patient and family. Previous studies have shown conflicting data on factors associated with increased LOS and are limited by using multiple different surgeries. Our study seeks to analyze factors that are associated with extended LOS. The objective of this study was to analyze data from 2 Food and Drug Administration trials of one-level cervical surgery to identify risk factors that are associated with extended LOS in the hospital. Extended LOS was defined to be >1 day. Patients with LOS ≤1 day were compared with those with LOS >1 day. Data from the BRYAN and Prestige ST Trial (n= 1004) were analyzed. Subjects with LOS ≤1 day were compared with those with LOS >1 day. Variables analyzed for their effect on LOS included demographic characteristics, patient-reported outcome measures, preoperative medical conditions, preoperative neurologic status, and intraoperative factors. A total of 912 patients (90.84%) had an LOS ≤1 day and 92 patients (9.16%) had an extended LOS >1 day. Weak narcotic medication use (P= 0.021; odds ratio [OR], 1.72), Nurick gait (P= 0.019; OR, 1.796), and operative time (P < 0.0001; OR, 2.062) were found to significantly affect LOS. Nurick gait, operative time, and history of weak narcotic use are associated with extended hospital stay. These data may be useful in preoperatively counseling patients, developing quality metrics for hospitals, and helping create financial models for cost/diagnosis-related group reimbursement for single-level anterior cervical surgery.

Assessment of Outcomes of Spine Surgery in Indian Athletes Involved in High-End Contact Sports.

Study DesignThis study was a retrospective analysis.PurposeThis study aimed to analyze the functional outcome following spinal surgery in elite athletes using return-to-play criteria.Overview of LiteratureSpinal ailments are relatively common in athletes and are bound to increase due to the ever-growing popularity of contact sports. An elite athlete is highly motivated to make a rapid recovery and return to full participation in sports. Although the criteria for diagnosis and surgical treatment of various spinal disorders in athletes have been well defined in the literature, there is no clear definition about the factors determining the return to play in athletes.MethodsThis study was a retrospective analysis of the data of 10 elite athletes who underwent spinal surgery for symptomatic degenerative disorder of the spine. Eight patients underwent lumbar spine surgery (two patients of microdiscectomy and six patients of fusion), and the remaining two patients underwent cervical spine surgery (one each anterior cervical discectomy and fusion and anterior cervical disc replacement). Outcome measures were investigated using return-to-training and return-to-sports criteria, as indicated by the length of time between surgery and return to competitive sports as parameters.ResultsOf the 10 patients, eight were males and two were females. The average age of the patients at the time of surgery was 32.4 years (range, 25–41 years). All patients returned to active participation of their sports. The average time for return to training was 7.3 weeks (range, 3–12 weeks). The average time for return to sports was 45.6 weeks (range, 36–72 weeks), and the average follow-up period was 59 months (range, 27–120 months).ConclusionsSpine surgery in an elite athlete involved in contact sports is safe and effective. Currently, there is a lack of standardized guidelines for return to sports after spine injuries. An athlete needs to be symptom-free, with full range of motion and full strength before returning to sports.

Cost-Effectiveness Analysis of Cervical Anterior Fusion and Cervical Artificial Disc Replacement in the Korean Medical System.

ObjectiveThis study is a retrospective cost-benefit analysis of cervical anterior interbody fusion and cervical artificial disc replacement, which are the main surgical methods to treat degenerative cervical disc disease. MethodsWe analyzed 156 patients who underwent anterior cervical disc fusion and cervical artificial disc replacement from January 1, 2008 to December 31, 2009, diagnosed with degenerative cervical disc disorder. In this study, the costs and benefits were analyzed by using quality adjusted life year (QALY) as the outcome index for patients undergoing surgery, and a Markov model was used for the analysis. Only direct medical costs were included in the analysis; indirect medical costs were excluded. Data were analyzed with TreeAge Pro 2015™ (TreeAge Software, Inc, Williamstown, MA, USA). ResultsPatients who underwent cervical anterior fusion had a total cost of KRW 2501807/USD 2357 over 5 years and obtained a utility of 3.72 QALY. Patients who underwent cervical artificial disc replacement received 4.18 QALY for a total of KRW 3685949/USD 3473 over 5 years. The cumulative cost-effectiveness ratio of cervical spine replacement surgery was KRW 2549511/QALY (USD 2402/QALY), which was lower than the general Korean payment standard. ConclusionBoth cervical anterior fusion and cervical artificial disc replacement are cost-effective treatments for patients with degenerative cervical disc disease. Cervical artificial disc replacement may be an effective alternative to obtain more benefits.

Local Retropharyngeal Administration of Corticosteroids: What's the Trade-Off?: Commentary on an article by Tyler James Jenkins, MD, et al.: "The Effect of Local Versus Intravenous Corticosteroids on the Likelihood of Dysphagia and Dysphonia Following Anterior Cervical Discectomy and Fusion. A Single-Blinded, Prospective, Randomized Controlled Trial".

Commentary Anterior cervical discectomy and fusion (ACDF) is one of the most commonly performed procedures in spine surgery. Clinical results have demonstrated that ACDF may be effectively utilized for a wide variety of indications, including degenerative spine conditions and spinal instabilities, as well as for the treatment of neural compression syndromes. One of the drawbacks associated with this type of procedure is the occurrence of dysphagia and/or dysphonia in a relevant number of patients. Although studies have reported beneficial effects of systemic administration of methylprednisolone perioperatively1,2, the study by Jenkins et al. is novel because it is one of the first studies to compare the efficacy of local retropharyngeal corticosteroids with intravenous (IV) corticosteroid administration. In this study, both the IV and local corticosteroid treatment groups had significantly positive effects on the reduction of dysphagia, dysphonia, and neck pain following ACDF compared with the control group, with the local corticosteroid group demonstrating an even more pronounced effect. Conversely, in a prospective, randomized, single-blinded controlled trial, Haws et al. suggested that intraoperative local corticosteroid administration may not provide additional benefit to patients undergoing ACDF procedures3. Thus, further studies must be conducted to assess the clinical efficacy of local versus systemic corticosteroid administration. The data from this study have the potential to influence the practice patterns of surgeons, and also the way that physicians may deal with this type of adverse event following ACDF. Considering the effect that these results may have on the future of patient care, it is paramount to take a closer look at the data presented in this study and how it compares with data from other studies on the subject. Nonsteroidal anti-inflammatory drugs (NSAIDs) have previously been reported to reduce the occurrence of heterotopic ossification and have therefore been utilized therapeutically in a wide variety of orthopaedic settings, including the cervical spine (i.e., postoperatively following anterior cervical disc replacement)4,5. Conversely, a possible counterproductive effect has been reported in situations in which a solid fusion and osteointegration of implants is the main aim, which explains why these substances are under close scrutiny following procedures such as ACDF6. Likewise, local corticosteroids have been associated with impaired wound healing and esophageal or pseudarthrosis complications, particularly when administered locally in the retropharyngeal space7. Unlike a systemic administration of NSAIDs, the application of the corticosteroids into the retropharyngeal space disperses a substantial amount of the drug directly into the targeted intervertebral disc space, surrounding both implants as well as the cortical/cancellous bone of the adjacent vertebral bodies. Therefore, it needs to be assessed and closely monitored whether the reduction in dysphagia and dysphonia may come at a tradeoff of raised nonunion rates in the medium and long term. As outlined by Jenkins et al., the study design and the power of the study did not permit a sound analysis of the rates of union versus nonunion, and hence this essential question cannot be answered in this present setting. In the local corticosteroid group, there were 29 patients with a mean age of 55.6 years (minimum age, 18 years), and patients were excluded for a variety of reasons (e.g., any revision procedure, general metabolic disease, etc.), which resulted in a ‘perfect cohort’ to achieve fusion. Additionally, all patients in the study received additional cervical plating, which should ultimately result in improved fusion rates. These aspects of the study design show that, by cohort definition as well as by the type of instrumentation used, the present patient sample is, in fact, characterized by an optimal predisposition to achieve a solid fusion. Nevertheless, 2 patients in the entire study were diagnosed with pseudarthrosis, with both cases belonging to the local corticosteroid group. Because the limited number of patients does not permit any valid statistical analysis, it is critical that future studies investigate whether these initial results may point to a larger underlying issue of reduced fusion rates related to local corticosteroid application into the retropharyngeal space. Overall, Jenkins et al. are to be congratulated for their substantial efforts with this well-designed study that assesses potential treatment modalities for a frequently underappreciated adverse event following ACDF. Future studies will need to investigate whether or not this positive effect of dysphagia and dysphonia reduction following retropharyngeal administration of local corticosteroids comes at a tradeoff with higher pseudarthrosis/nonunion rates, whether this local administration will coincide with a higher risk of complications such as esophageal perforations, and whether improved clinical results can actually be confirmed in the medium and long term.

NuNec™ Cervical Disc Arthroplasty Improves Quality of Life in Cervical Radiculopathy and Myelopathy: A 2-yr Follow-up.

Anterior cervical disc replacement is an alternative to fusion for the treatment of selected cases of radiculopathy and myelopathy. We report clinical and radiological outcomes after disc replacement with the NuNec™ artificial cervical disc (Pioneer® Surgical Technology, Marquette, Michigan) with subgroup analysis. To review clinical and radiological outcomes after anterior cervical disc replacement with the NuNec™ artificial cervical disc. A consecutive case series of patients undergoing cervical disc replacement with the NuNec™ artificial disc was conducted. Clinical outcomes were assessed by questionnaires preoperatively and up to 2 yr postoperatively including neck and arm pain, Neck Disability Index, Euroqol 5-dimensions, and Short Form-36; x-rays from the same period were analyzed for range of movement and presence of heterotopic ossification. A total of 44 NuNec™ discs were implanted in 33 patients. Clinical improvements were seen in all outcomes; significant improvements on the Neck Disability Index, Euroqol 5-dimensions, and physical domain of the Short Form-36 were maintained at 2 yr. There was a mean of 4° range of movement at the replacement disc level at 2 yr, a significant reduction from baseline; there was also progression in levels of heterotopic ossification. Complications included temporary dysphagia (10%) and progression of disease requiring foraminotomy (6%); no surgery for adjacent level disease was required. There was no significant difference in the outcomes of the radiculopathy and myelopathy groups. Clinical outcomes using the NuNec™ disc replacement are comparable with other disc replacements. Although the range of movement is reduced, the reoperation rate is very low.