Machine learning models on a web application to predict short-term postoperative outcomes following anterior cervical discectomy and fusion.

BACKGROUND: The frequency of anterior cervical discectomy and fusion (ACDF) has increased up to 400% since 2011, underscoring the need to preoperatively anticipate adverse postoperative outcomes given the procedure's expanding use. Our study aims to accomplish two goals: firstly, to develop a suite of explainable machine learning (ML) models capable of predicting adverse postoperative outcomes following ACDF surgery, and secondly, to embed these models in a user-friendly web application, demonstrating their potential utility. METHODS: We utilized data from the National Surgical Quality Improvement Program database to identify patients who underwent ACDF surgery. The outcomes of interest were four short-term postoperative adverse outcomes: prolonged length of stay (LOS), non-home discharges, 30-day readmissions, and major complications. We utilized five ML algorithms - TabPFN, TabNET, XGBoost, LightGBM, and Random Forest - coupled with the Optuna optimization library for hyperparameter tuning. To bolster the interpretability of our models, we employed SHapley Additive exPlanations (SHAP) for evaluating predictor variables' relative importance and used partial dependence plots to illustrate the impact of individual variables on the predictions generated by our top-performing models. We visualized model performance using receiver operating characteristic (ROC) curves and precision-recall curves (PRC). Quantitative metrics calculated were the area under the ROC curve (AUROC), balanced accuracy, weighted area under the PRC (AUPRC), weighted precision, and weighted recall. Models with the highest AUROC values were selected for inclusion in a web application. RESULTS: The analysis included 57,760 patients for prolonged LOS [11.1% with prolonged LOS], 57,780 for non-home discharges [3.3% non-home discharges], 57,790 for 30-day readmissions [2.9% readmitted], and 57,800 for major complications [1.4% with major complications]. The top-performing models, which were the ones built with the Random Forest algorithm, yielded mean AUROCs of 0.776, 0.846, 0.775, and 0.747 for predicting prolonged LOS, non-home discharges, readmissions, and complications, respectively. CONCLUSIONS: Our study employs advanced ML methodologies to enhance the prediction of adverse postoperative outcomes following ACDF. We designed an accessible web application to integrate these models into clinical practice. Our findings affirm that ML tools serve as vital supplements in risk stratification, facilitating the prediction of diverse outcomes and enhancing patient counseling for ACDF.

Postoperative Airway Management after Anterior Cervical Spine Surgery: Retrospective Neurosurgical Multicenter Study.

Airway complications that occur after anterior cervical spine surgery pose a life-threatening risk, which encompasses complications including prolonged intubation, unplanned reintubation, and/or necessity of tracheostomy. The present study aimed to identify the surgical risks associated with postoperative airway complications in neurosurgical training institutes. A retrospective, multicenter, observational review of data from 365 patients, who underwent anterior cervical spine surgery between 2018 and 2022, at three such institutes was carried out. Postoperative airway complication was defined as either the need for prolonged intubation on the day of surgery or the need for unplanned reintubation. The perioperative medical information was obtained from their medical records. The average age of the cohort was over 60 years, with males comprising approximately 70%. Almost all surgeries predominantly involved anterior cervical discectomy and fusion or anterior cervical corpectomy and fusion, with most surgeries occurring at the level of C5/6. In total, 363 of 365 patients (99.5%) were extubated immediately after surgery, and the remaining two patients were kept under intubation because of the risk of airway complications. Of the 363 patients who underwent extubation immediately after surgery, two (0.55%) required reintubation because of postoperative airway complications. Patients who experienced airway complications were notably older and exhibited a significantly lower body mass index. The results of this study suggested that older and frailer individuals are at an elevated risk for postoperative airway complications, with immediate postoperative extubation generally being safe but requiring careful judgment in specific cases.

Comparative outcomes of obese and non-obese patients with lumbar disc herniation receiving full endoscopic transforaminal discectomy: a systematic review and meta-analysis.

OBJECTIVE: This study aimed to assess the impact of full endoscopic transforaminal discectomy (FETD) on clinical outcomes and complications in both obese and non-obese patients presenting with lumbar disc herniation (LDH). METHODS: A systematic search of relevant literature was conducted across various primary databases until November 18, 2023. Operative time and hospitalization were evaluated. Clinical outcomes included preoperative and postoperative assessments of the Oswestry Disability Index (ODI) and visual analogue scale (VAS) scores, conducted to delineate improvements at 3 months postoperatively and during the final follow-up, respectively. Complications were also documented. RESULTS: Four retrospective studies meeting inclusion criteria provided a collective cohort of 258 patients. Obese patients undergoing FETD experienced significantly longer operative times compared to non-obese counterparts (P = 0.0003). Conversely, no statistically significant differences (P > 0.05) were observed in hospitalization duration, improvement of VAS for back and leg pain scores at 3 months postoperatively and final follow-up, improvement of ODI at 3 months postoperatively and final follow-up. Furthermore, the overall rate of postoperative complications was higher in the obese group (P = 0.02). The obese group demonstrated a total incidence of complications of 17.17%, notably higher than the lower rate of 9.43% observed in the non-obese group. CONCLUSION: The utilization of FETD for managing LDH in individuals with obesity is associated with prolonged operative times and a higher total complication rate compared to their non-obese counterparts. Nevertheless, it remains a safe and effective surgical intervention for treating herniated lumbar discs in the context of obesity.

Preoperative MRI-based endplate quality: a novel tool for predicting cage subsidence after anterior cervical spine surgery.

PURPOSE: The objective of this study was to examine the predictive value of a newly developed MRI-based Endplate Bone Quality (EBQ) in relation to the development of cage subsidence following anterior cervical discectomy and fusion (ACDF). METHODS: Patients undergoing ACDF for degenerative cervical diseases between January 2017 and June 2022 were included. Correlation between EBQ scores and segmental height loss was analyzed using Pearson's correlation. ROC analyses were employed to ascertain the EBQ cut-off values that predict the occurrence of cage subsidence. Multivariate logistic regression analyses were conducted to identify the risk factors associated with postoperative cage subsidence. RESULTS: 23 individuals (14.56%) exhibited the cage subsidence after ACDF. In the nonsubsidence group, the average EBQ and lowest T-score were determined to be 4.13 ± 1.14 and - 0.84 ± 1.38 g/cm2 respectively. In contrast, the subsidence group exhibited a mean EBQ and lowest T-score of 5.38 ± 0.47 (p < 0.001) and - 1.62 ± 1.34 g/cm2 (p = 0.014), respectively. There was a significant positive correlation (r = 0.798**) between EBQ and the segmental height loss. The EBQ threshold of 4.70 yielded optimal sensitivity (73.9%) and specificity (93.3%) with AUC of 0.806. Furthermore, the lowest T-score (p = 0.045, OR 0.667) and an elevated cervical EBQ score (p < 0.001, OR 8.385) were identified as significant risk factors for cage subsidence after ACDF. CONCLUSIONS: The EBQ method presents itself as a promising and efficient tool for surgeons to assess patients at risk of cage subsidence and osteoporosis prior to cervical spine surgery, utilizing readily accessible patient data.

Safety and efficacy of day anterior cervical discectomy and fusion procedure for degenerative cervical spondylosis: a retrospective analysis.

OBJECTIVE: Our study aimed to develop a day anterior cervical discectomy and fusion (ACDF) procedure to treat degenerative cervical spondylosis (DCS). The goal was to analyze its clinical implications, safety, and early effects to provide a better surgical option for eligible DCS patients. METHODS: A retrospective analysis was performed to identify DCS patients who underwent day ACDF from September 2022 to August 2023. The operative time, intraoperative blood loss, postoperative drainage, preoperative and postoperative visual analog scale (VAS) scores, neck disability index (NDI) scores, Japanese Orthopedic Association (JOA) scores, JOA recovery rate (RR), incidence of dysphagia-related symptoms, 30-day hospital readmission rate, and incidence of other complications were recorded to evaluate early clinical outcomes. Radiography was performed to assess the location of the implants, neurological decompression, and cervical physiological curvature. RESULTS: All 33 patients (23 women and 10 men) underwent successful surgery and experienced significant symptomatic and neurological improvements. Among them, 26 patients underwent one-segment ACDF, 5 underwent two-segment ACDF, and 2 underwent three-segment ACDF. The average operative time was 71.1 ± 20.2 min, intraoperative blood loss was 19.1 ± 6.2 mL, and postoperative drainage was 9.6 ± 5.8 mL. The preoperative VAS and NDI scores improved postoperatively (7.1 ± 1.2 vs. 3.1 ± 1.3 and 66.7% ± 4.8% vs. 24.1% ± 2.5%, respectively), with a significant difference (P < 0.01). Moreover, the preoperative JOA scores improved significantly postoperatively (7.7 ± 1.3 vs. 14.2 ± 1.4; P < 0.01) with an RR of 93.9% in good or excellent. Postoperative dysphagia-related symptoms occurred in one patient (3.0%). During the follow-up period, no patient was readmitted within 30 days after discharge; however, an incisional hematoma was reported in one patient on the 6th day after discharge, which was cured by pressure dressing. The postoperative radiographs revealed perfect implant positions and sufficient nerve decompression in all patients. Furthermore, the preoperative cervical physiological curvature improved significantly after the operation (14.5° ± 4.0° vs. 26.3° ± 5.4°; P < 0.01). CONCLUSIONS: Day ACDF has good safety and early clinical efficacy, and it could be an appropriate choice for eligible DCS patients.

Comparison of one-hole split endoscopic discectomy and microendoscopic discectomy in the treatment of lumbar disk herniation: a one-year retrospective cohort study.

BACKGROUND: We aim to compare and assess the surgical parameters and follow-up information of one-hole split endoscopic discectomy (OSE) and microendoscopic discectomy (MED) in the treatment of LDH. METHODS: This study included 154 patients with degenerative lumbar disk disease. Sixty-eight patients underwent OSE and 86 patients MED. The VAS score for lower back and lower limb radiation pain, ODI score, modified MacNab score, estimated blood loss (EBL), length of the incision, amount of C-reactive protein, and recurrence and complication rates were examined as indicators for clinical outcomes and adverse events. RESULTS: After surgery, the VAS and ODI scores in the two groups significantly decreased. On the third day after surgery, the VAS and ODI scores of the OSE group were significantly better than those of the MED group. The VAS and ODI scores preoperatively and at 1 month, 3 months, 6 months, and 12 months following the procedure did not substantially vary between the two groups. There was less EBL and a shorter incision with OSE than with MED. There was no significant difference in the rate of complications between the two groups. CONCLUSION: Compared with MED, OSE is a new alternative option for LDH that can achieve similar and satisfactory clinical outcomes. Furthermore, OSE has many advantages, including less EBL and a smaller incision. Further clinical studies are needed to confirm the effectiveness of OSE.

Postoperative complications associated with anterior cervical discectomy and three years follow-up.

INTRODUCTION: Anterior cervical discectomy (ACD) is used in the surgical treatment of cervical degenerative disc disease (DDD). Besides the low incidence of postoperative complications, they can affect the postoperative course for patients. MATERIAL AND METHODS: From January 2015 to December 2019, 789 cervical DDD patients with ACD were investigated. This study aims to identify the risk factors for postoperative complications and evaluate the quality of life for ACD patients using the Visual Analog Pain Scale (VAS) and Neck Disability Index (NDI). RESULTS: Among the 789 cervical patients, postoperative complications were identified in 88 patients. In analyzing independently risk factors for postoperative complications, we don't record the male gender, age, number of treated segments, diabetes mellitus, and hypertension with significant risk. A BMI higher than 23.5, a longer surgery of more than 82.5 min, and blood loss of more than 95 ml were found as independent risk factors for postoperative complications. The three-year follow-up quality of life was evaluated in 565 because of the loss of 224 patients. We found improved quality of life in the whole group of patients. Moreover, we have not confirmed significant differences in groups of patients, with and without postoperative complications. CONCLUSION: The result of our study documented a low incidence of postoperative complications after ACD. We identified high BMI level, increased blood loss, and prolonged operation time as independent risk factors for the increased incidence of postoperative complications. Moreover, we demonstrated that postoperative complications do not significantly influence the patient's quality of life (Tab. 5, Ref. 32).

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

BACKGROUND CONTEXT: Anterior 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. PURPOSE: The 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/SETTING: Retrospective Cohort Review. PATIENT SAMPLE: A 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. METHODS: A 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. RESULTS: The 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). CONCLUSION: Our 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.

Intraoperative Protection of Pharyngeal Autonomic Nerves: Preventing Dysphagia After Anterior Cervical Decompression and Fusion Surgery.

OBJECTIVE: The study aims to investigate whether intraoperative protection of the pharyngeal autonomic nerve can effectively reduce the incidence of postoperative dysphagia following anterior cervical decompression and fusion surgery (ACDF). METHODS: A retrospective analysis was conducted on 130 cases that underwent ACDF from January 2018 to June 2022 at our hospital. Divided into nonautonomic neuroprotection (NANP) group and autonomic neuroprotection group based on whether receive protective measures for the pharyngeal autonomic nerve during surgery. General data were recorded and compared between the 2 groups. Postoperative outcomes were evaluated using Neck Disability Index, Japanese Orthopaedics Association (JOA) score, and JOA improvement rate. The incidence and severity of postoperative dysphagia were assessed using Bazaz dysphagia assessment criteria and swallowing-quality of life questionnaire. RESULTS: There were no significant differences in general data (P > 0.05). The average operation time and intraoperative blood loss also showed no significant differences (P > 0.05). Both groups showed significant improvements in Neck Disability Index and JOA scores at all follow-up time points compared to preoperative scores (P < 0.01). The incidence of postoperative dysphagia in the autonomic neuroprotection group was significantly lower than that in the NANP group at all follow-up time points (P < 0.05). Both group showed a significant reduction in scores 3 days postoperatively compared to preoperative scores (P < 0.01), and the NANP group also showed significant reductions in scores at 3 month and 1 year postoperative follow-up time points compared to preoperative scores (P < 0.01). CONCLUSIONS: The adoption of pharyngeal autonomic nerve protective measures during ACDF can effectively lower the probability of postoperative dysphagia.

The efficacy and safety of ultrasonic bone scalpel for removing retrovertebral osteophytes in anterior cervical discectomy and fusion: A retrospective study.

In this study, we present a novel surgical method that utilizes the ultrasonic bone scalpel (UBS) for the removal of large retrovertebral osteophytes in anterior cervical discectomy and fusion (ACDF) and evaluate its safety and efficacy in comparison to the traditional approach of using high-speed drill (HSD). A total of 56 patients who underwent ACDF for retrovertebral osteophytes were selected. We recorded patients' baseline information, operation time, intraoperative blood loss, complications, JOA and VAS scores, and other relevant data. The mean operation time and the mean intraoperative blood loss in the UBS group were less than those in the HSD group (P < 0.05). Although both groups exhibited considerable improvements in JOA and VAS scores following surgery, there was no statistically significant difference between the two groups (P > 0.05). Additionally, no significant disparities were found in bone graft fusion between the two groups at 6- and 12-months postsurgery. Notably, neither group exhibited complications such as dura tear or spinal cord injury. Our study found that the use of UBS reduced operative time, minimized surgical bleeding, and led to clinical outcomes comparable to HSD in ACDF. This technique offers an effective and safe method of removing large retrovertebral osteophytes.

Bone resorption around the annular closure device during a postoperative follow-up of 8 years.

OBJECTIVE: Annular closure device (ACD) implantation is considered to be an effective means of preventing reherniation after microdiscectomy; however, there is an issue: the bone may resorb around the ACD. The causes of vertebral bone resorption remain unexplored; the dynamics of changes in bone resorption around the ACD have not yet been assessed or characterized. METHODS: One hundred thirty-three patients underwent ACD implantation after microdiscectomy, and 107 of them were followed up for 8 years after surgery (Oswestry, VAS). Lumbar CT scans helped characterize the bone resorption area around the ACD. RESULTS: The median of follow-up was 85 [74; 93] months (from 73 to 105 months). The prevalence of bone resorption around the ACD was up to 63.6%, and it was mainly around the polymer mesh of the ACD (70.6%). The resorbed bone volume increased with time and reached its maximum of 5.2 cm3 (12% of the vertebral body volume) once a sclerotic rim developed around the bone resorption area. No differences in VAS pain intensity or in Oswestry Disability Index were found between patients with resorption and patients without it (p > 0.05). The volume of the intervertebral disc before surgery is a predictor of bone resorption (OR = 0.79, p = 0.009): if it is less than 13.2 cm3, the risk of bone resorption increases significantly (p < 0.05). CONCLUSION: The majority of patients (up to 63.6%) with implanted ACDs have vertebral bone resorption around them. The bone resorption area around the ACD mesh increases with time to up to 12% of the vertebral body volume, with no clinical evidence, though. The formation of a sclerotic rim prevents the bone resorption area from further growth. If the volume of the intervertebral disc before surgery is less than 13.2 cm3, the risk of bone resorption increases significantly.

Association between spinal manipulative therapy and lumbar spine reoperation after discectomy: a retrospective cohort study.

BACKGROUND: Patients who undergo lumbar discectomy may experience ongoing lumbosacral radiculopathy (LSR) and seek spinal manipulative therapy (SMT) to manage these symptoms. We hypothesized that adults receiving SMT for LSR at least one year following lumbar discectomy would be less likely to undergo lumbar spine reoperation compared to matched controls not receiving SMT, over two years' follow-up. METHODS: We searched a United States network of health records (TriNetX, Inc.) for adults aged ≥ 18 years with LSR and lumbar discectomy ≥ 1 year previous, without lumbar fusion or instrumentation, from 2003 to 2023. We divided patients into two cohorts: (1) chiropractic SMT, and (2) usual care without chiropractic SMT. We used propensity matching to adjust for confounding variables associated with lumbar spine reoperation (e.g., age, body mass index, nicotine dependence), calculated risk ratios (RR), with 95% confidence intervals (CIs), and explored cumulative incidence of reoperation and the number of SMT follow-up visits. RESULTS: Following propensity matching there were 378 patients per cohort (mean age 61 years). Lumbar spine reoperation was less frequent in the SMT cohort compared to the usual care cohort (SMT: 7%; usual care: 13%), yielding an RR (95% CIs) of 0.55 (0.35-0.85; P = 0.0062). In the SMT cohort, 72% of patients had ≥ 1 follow-up SMT visit (median = 6). CONCLUSIONS: This study found that adults experiencing LSR at least one year after lumbar discectomy who received SMT were less likely to undergo lumbar spine reoperation compared to matched controls not receiving SMT. While these findings hold promise for clinical implications, they should be corroborated by a prospective study including measures of pain, disability, and safety to confirm their relevance. We cannot exclude the possibility that our results stem from a generalized effect of engaging with a non-surgical clinician, a factor that may extend to related contexts such as physical therapy or acupuncture. REGISTRATION: Open Science Framework ( https://osf.io/vgrwz ).

Network Meta-Analysis of C5 Palsy After Anterior Cervical Decompression of Three to Six Levels: Comparing Three Different Procedures.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: Using a network meta-analysis (NMA), this study aimed to compare the risks of C5 palsy after three different procedures of anterior cervical decompression. SUMMARY OF BACKGROUND DATA: C5 palsy is a well-known complication affecting the quality of life after anterior procedures. Due to the limited evidence on the various procedures available, we evaluate the basis for selection to prevent palsy and achieve maximal decompression in cases spanning 3-6 levels. MATERIALS AND METHODS: We conducted a comprehensive search for C5 palsy and complications after 3representative procedures, including anterior cervical discectomy and fusion (ACDF), anterior cervical corpectomy and fusion (ACCF), and their combination (hybrid), involving 3 to 6 intervertebral levels. The incidence of C5 palsy was compared using a NMA. RESULTS: We identified 1655 patients in 11 studies who met inclusion criteria. Sixty-nine patients (4.2%) developed delayed C5 palsies. The incidences among ACDF, ACCF, and hybrid cases were 2.3% (16/684, 95% CI: 1.4% to 3.8%), 6.4% (39/613, 95% CI: 4.7% to 8.6%), and 3.9% (14/358, 95% CI: 2.3% to 6.5%), respectively ( P < 0.01). A NMA was performed for 15 pairwise comparisons across the 3 procedure arms: ACDF versus hybrid, 7/232 (3.0%) versus 11/234 (4.7%); hybrid versus ACCF, 14/301 (4.3%) versus 18/224 (8.0%); ACCF versus ACDF, 38/523 (7.8%) versus 16/619 (2.6%). Compared with ACDF, the risk of C5 palsy was significantly higher in ACCF (odds ratio: 2.72, 95% CI: 1.47 to 5.01), whereas ACDF versus hybrid did not significantly differ in risk (odds ratio: 1.56, 95% CI: 0.68 to 3.60). CONCLUSION: We determined that ACCF was associated with a higher risk of postoperative C5 palsy than ACDF in cases spanning 3 to 6 intervertebral levels. If practicable, ACDF surgery may be an appropriate choice for cases requiring anterior decompression of 3 to 6 levels. LEVEL OF EVIDENCE: Level III.

Cannabis use Disorder and Complications After Anterior Cervical Diskectomy and Fusion.

OBJECTIVE: The aim of this study, a retrospective database analysis, was to assess the impact of baseline cannabis use disorder (CUD) on perioperative complication outcomes in patients undergoing primary 1- to 2-level anterior cervical diskectomy and fusion (ACDF) surgery. METHODS: The PearlDiver Database was queried from January 2010 to December 2021 for patients who underwent primary 1- to 2-level ACDF surgery for degenerative spine disease. Patients with CUD diagnosis 6 months before the index ACDF surgery (i.e., CUD) were propensity matched with patients without CUD (i.e., control in a ratio of 1:1, employing age, gender, and Charlson Comorbidity Index as matching covariates). Univariate and multivariable analysis models with adjustment of confounding variables were used to evaluate the risk of CUD on perioperative complications between the propensity-matched cohorts. RESULTS: The 1:1 matched cohort included 838 patients in each group. Following multivariate analysis, CUD was demonstrated to be associated with an increased incidence of hospital readmission at 90 days (odds ratio [OR] = 2.64, 95% confidence interval: [1.19 to 6.78], [P = 0.027]) and revision surgery at 1 year postoperative (OR = 3.36, 95% confidence interval: [1.17 to 14.18], [P = 0.049]). CUD was additionally associated with reduced risk of overall medical complications at both 6 months and 1 year postoperative (OR = 0.55, [P = 0.021], and OR = 0.54, [P = 0.015], respectively). CONCLUSIONS: These findings indicate that isolated baseline CUD is associated with an increased risk of hospital readmission at 90 days postoperative and cervical spine reoperation at 1 year after primary 1- to 2-level ACDF surgery with a decrease in overall medical complications, cardiac arrhythmias, and acute renal failure.

Headache relief 10 years after cervical disc arthroplasty: multicenter randomized clinical trial post hoc analysis.

OBJECTIVE: Headache relief after anterior cervical spine surgery has been reported. No study, however, has followed patients out to 10 years to assess the durability of headache improvement. The authors analyzed a group of patients with a 10-year follow-up after one- or two-level cervical disc arthroplasty (CDA) from an FDA investigational device exemption (IDE) study. METHODS: The authors performed a post hoc analysis of 189 patients treated with CDA from the 9 highest enrolling sites in a prospective multicenter randomized US FDA IDE clinical trial. Patients had one- or two-level CDA at contiguous levels from C3 to C7 using the Mobi-C device. The authors evaluated headache scores from the headache section of the Neck Disability Index (NDI), along with associated demographic variables (age, sex, race, ethnicity, and BMI). Preoperative and 10-year postoperative headache scores were analyzed. Primary analysis was conducted via the Wilcoxon rank-sum test, followed by univariate and multivariable logistic regression. RESULTS: After accounting for age, BMI, race, ethnicity, and sex, there was sustained headache improvement 10 years after CDA (p = 0.04). Preoperatively, the median NDI score was 3.00 (IQR 1.00-4.00) and after 10 years it was 1.00 (IQR 0.00-2.00), with a decrease in the NDI score by 1.00 point (95% CI 0.00-2.00, p = 0.04). For one-level CDA, the median NDI score was 3.00 (IQR 1.00-4.00) preoperatively but 1.00 (IQR 0.00-2.00) at 10 years, with an estimated reduction in the NDI score of 1 point (95% CI 1.00-2.00, p < 0.0001). For two-level CDA, the median NDI score was 3.00 (IQR 1.75-4.00) preoperatively and 1.00 (IQR 0.00-2.00) at 10 years, with an estimated reduction in the NDI score of 1 point (95% CI 1.00-2.00, p < 0.0001). CONCLUSIONS: Headache relief provided by cervical CDA, for symptomatic C3-7 cervical spondylosis, was sustained even 10 years after surgery. There was no difference in headache improvement between the one- and two-level CDA groups, or among BMI, sex, race, and ethnicity strata.

Should patient eligibility criteria for cervical disc arthroplasty (CDA) be expanded? A retrospective cohort analysis of relatively contraindicated patients undergoing CDA.

BACKGROUND CONTEXT: Cervical disc arthroplasty (CDA) is a safe and effective alternative to anterior cervical discectomy and fusion (ACDF) in the treatment of various degenerative pathologies with advantages of motion preservation and lower rates of adjacent segment degeneration (ASD). Absolute contraindications for CDA have been well outlined in order to prevent adverse outcomes in patients. However, in cases of patients with relative contraindications (kyphotic deformity, prior cervical surgery, etc.), there remains controversy. There is minimal literature evaluating long-term outcomes in this patient population. PURPOSE: To compare long-term clinical and functional outcomes of CDA in typical patients versus those with relative contraindications. DESIGN: Retrospective cohort review. PATIENT SAMPLE: Eighty-nine patients were included in the study: 55 (no contraindications) in Group 1 and 34 (relatively contraindicated) in Group 2 and 26 (preoperative segmental kyphosis) in Group 3. 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. METHODS: Patients were placed in the relatively contraindicated cohort if they possessed at least one of the following: (1) segmental kyphosis of 5° to 10°, (2) significant loss of disc height (between 50% and 75% of initial measurements or 1.5-3mm), (3) bridging osteophytes, and (4) prior cervical spine surgery based on preoperative cervical radiographs. The other cohort included patients without any relative contraindication who underwent CDA over the same time frame. Additionally, a subgroup analysis was used to compare those without any contraindications to those with only preoperative segmental kyphosis. Patients were included in this study if they met the following criteria: over 18 years of age, minimum follow-up of 24 months, and availability of complete medical records. Patient demographics, levels operated on, and perioperative outcomes were assessed between the two groups. Revision and complication rates were recorded. Functional outcomes scores were compared using VAS and NDI scores at 6-months, 12-months and final follow-up. RESULTS: Mean follow-up was 40.8 months in Group 1 and 38.3 months in Group 2 (p=.569). Complication rates were 21.8% in Group 1 and 26.4% in Group 2 (p=.615). Complication rates in a comparison between Groups 1 and 3 were statistically insignificant (p=.383). The most common complication was transient approach-related postoperative dysphagia (Group 1: 20% vs Group 2: 23.5%, p=.693). No significant differences were observed in the rates of transient dysphonia (Group 1: 0.0% vs Group 2: 2.9%, p=.201), adjacent segment degeneration (ASD) (Group 1: 1.8% vs Group 2: 0.0%, p=.429), infection (Group 1: 1.8% vs Group 2: 2.9%, p=.712), heterotopic ossification (Group 1: 49.1% vs Group 2: 50.0%, p=.934) or spontaneous fusion (Group 1: 1.8% vs Group 2: 2.9%, p=.728). No revision surgeries were observed in either cohort. All three groups demonstrated significant improvements in their VAS and NDI scores compared with preoperative measurements (p<.001), but no significant differences were found in the degree of improvement between groups at any point in time. CONCLUSIONS: Our study found no significant differences in clinical and functional outcomes between patients undergoing 1- and 2-level CDA with relative contraindications versus typical patients. These findings suggest that patient eligibility criteria for CDA may warrant expansion. However, future prospective studies over a longer period of follow-up are necessary to corroborate our results.

Association Between Age-stratified Cohorts and Perioperative Complications and 30-day and 90-day Readmission in Patients Undergoing Single-level Anterior Cervical Discectomy and Fusion.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To assess perioperative complication rates and readmission rates after ACDF in a patient population of advanced age. SUMMARY OF BACKGROUND DATA: Readmission rates after ACDF are important markers of surgical quality and, with recent shifts in reimbursement schedules, they are rapidly gaining weight in the determination of surgeon and hospital reimbursement. METHODS: Patients 18 years of age and older who underwent elective single-level ACDF were identified in the National Readmissions Database (NRD) and stratified into 4 cohorts: 18-39 ("young"), 40-64 ("middle"), 65-74 ("senior"), and 75+ ("elderly") years of age. For each cohort, the perioperative complications, frequency of those complications, and number of patients with at least 1 readmission within 30 and 90 days of discharge were analyzed. χ 2 tests were used to calculate likelihood of complications and readmissions. RESULTS: There were 1174 "elderly" patients in 2016, 1072 in 2017, and 1010 in 2018 who underwent ACDF. Their rate of any complication was 8.95%, 11.00%, and 13.47%, respectively ( P <0.0001), with dysphagia and acute posthemorrhagic anemia being the most common across all 3 years. They experienced complications at a greater frequency than their younger counterparts (15.80%, P <0.0001; 16.98%, P <0.0001; 21.68%, P <0.0001). They also required 30-day and 90-day readmission more frequently ( P <0.0001). CONCLUSION: It has been well-established that advanced patient age brings greater risk of perioperative complications in ACDF surgery. What remains unsettled is the characterization of this age-complication relationship within specific age cohorts and how these complications inform patient hospital course. Our study provides an updated analysis of age-specific complications and readmission rates in ACDF patients. Orthopedic surgeons may account for the rise in complication and readmission rates in this population with the corresponding reduction in length and stay and consider this relationship before discharging elderly ACDF patients.

Clinical and cost-effectiveness of PCF versus ACD in the treatment of cervical brachialgia (FORVAD trial).

BACKGROUND: Cervical radiculopathy occurs when a nerve root is compressed in the spine, if symptoms fail to resolve after 6 weeks surgery may be indicated. Anterior Cervical Discectomy (ACD) is the commonest procedure, Posterior Cervical Foraminotomy (PCF) is an alternative that avoids the risk of damage to anterior neck structures. This prospective, Phase III, UK multicentre, open, individually randomised controlled trial was performed to determine whether PCF is superior to ACD in terms of improving clinical outcome as measured by the Neck Disability Index (NDI) 52 weeks post-surgery. METHOD: Following consent to participate and collection of baseline data, subjects with cervical brachialgia were randomised to ACD or PCF in a 1:1 ratio on the day of surgery. Clinical outcomes were assessed on day 1 and patient reported outcomes on day 1 and weeks 6, 12, 26, 39 and 52 post-operation. A total of 252 participants were planned to be randomised. Statistical analysis was limited to descriptive statistics. Health economic outcomes were also described. RESULTS: The trial was closed early (n = 23). Compared to baseline, the median (interquartile range (IQR)) NDI score at 52 weeks reduced from 44.0 (36.0, 62.0) to 25.3 (20.0, 42.0) in the PCF group and increased from 35.6 (34.0, 44.0) to 45.0 (20.0, 57.0) in the ACD group. ACD may be associated with more swallowing, voice and other complications and was more expensive; neck and arm pain scores were similar. CONCLUSIONS: The trial was closed early, therefore no definitive conclusions on clinical or cost-effectiveness could be made.

Early Voice and Swallowing Disturbance Incidence and Risk Factors After Revision Anterior Cervical Discectomy and Fusion Using a Multidisciplinary Surgical Approach: A Retrospective Cohort Evaluation of a Prospective Database.

BACKGROUND AND OBJECTIVES: Dysphagia and vocal cord palsy (VCP) are common otolaryngological complications after revision anterior cervical discectomy and fusion (rACDF) procedures. Our objective was to determine the early incidence and risk factors of VCP and dysphagia after rACDF using a 2-team approach. METHODS: Single-institution, retrospective analysis of a prospectively collected database of patients undergoing rACDF was enrolled from September 2010 to July 2021. Of 222 patients enrolled, 109 patients were included in the final analysis. All patients had prior ACDF surgery with planned revision using a single otolaryngologist and single neurosurgeon. MD Anderson Dysphagia Inventory and fiberoptic endoscopic evaluation of swallowing (FEES) were used to assess dysphagia. VCP was assessed using videolaryngostroboscopy. RESULTS: Seven patients (6.7%) developed new postoperative VCP after rACDF. Most cases of VCP resolved by 3 months postoperatively (mean time-to-resolution 79 ± 17.6 days). One patient maintained a permanent deficit. Forty-one patients (37.6%) reached minimum clinically important difference (MCID) in their MD Anderson Dysphagia Inventory composite scores at the 2-week follow-up (MCID decline of ≥6), indicating new clinically relevant swallowing disturbance. Forty-nine patients (45.0%) had functional FEES Performance Score decline. On univariate analysis, there was an association between new VCPs and the number of cervical levels treated at revision ( P = .020) with long-segment rACDF (≥4 levels) being an independent risk factor ( P = .010). On linear regression, there was an association between the number of levels treated previously and at revision for FEES Performance Score decline ( P = .045 and P = .002, respectively). However, on univariate analysis, sex, age, body mass index, operative time, alcohol use, smoking, and individual levels revised were not risk factors for reaching FEES Performance Score decline nor MCID at 2 weeks postoperatively. CONCLUSION: VCP is more likely to occur in long-segment rACDF but is often temporary. Clinically relevant and functional rates of dysphagia approach 37% and 45%, respectively, at 2 weeks postoperatively after rACDF.

The impact of being overweight or obese on 12 month clinical recovery in patients following lumbar microdiscectomy for radiculopathy.

BACKGROUND CONTEXT: The proportion of patients who undergo lumbar microdiscectomy due to lumbar radiculopathy who are also overweight or obese is high. However, whether high body mass index (BMI) affects clinical outcomes is not well-studied. PURPOSE: To investigate the difference in the clinical course between normal weight, overweight, and obese patients with radiculopathy who underwent lumbar microdiscectomy followed by physical therapy and to evaluate whether high BMI is associated with poor recovery. STUDY DESIGN/SETTING: A prospective cohort study with a 12-month follow-up was conducted in a multidisciplinary clinic. PATIENT SAMPLE: We included 583 patients (median [IQR] age: 45 [35-52] years; 41% female) with clinical signs and symptoms of lumbar radiculopathy, consistent with magnetic resonance imaging findings, who underwent microdiscectomy followed by postoperative physical therapy. OUTCOME MEASURES: Outcomes were leg pain and back pain intensity measured with a visual analogue scale, disability measured with the Roland Morris Disability Questionnaire at 3 and 12-month follow-ups, and complications. METHODS: Patients were classified as being normal weight (46.9%), overweight (38.4%), or obese (14.7%). A linear mixed-effects model was used to assess the difference in the clinical course of pain and disability between the three BMI categories. The association between BMI and outcomes was evaluated using univariable and multivariable logistic regression analyses. RESULTS: All three patient groups experienced a significant improvement in leg pain, back pain, and disability over 3 and 12-month follow-up. Patients who were overweight, obese, or normal weight experienced comparable leg pain (p=.14) and disability (p=.06) over the clinical course (p=.14); however, obese patients experienced higher back pain (MD=-6.81 [95%CI: -13.50 to -0.14]; p=.03). The difference in back pain scores was not clinically relevant. CONCLUSIONS: In the first year following lumbar microdiscectomy, patients demonstrated clinical improvements and complications that were unrelated to their preoperative BMI.