Impact of Age and Duration of Symptoms on Surgical Outcome of Single-Level Microscopic Anterior Cervical Discectomy and Fusion in the Patients with Cervical Spondylotic Radiculopathy

Impact of Preoperative Symptom Duration on Patient-Reported Outcomes Following Cervical Disc Replacement for Cervical Radiculopathy

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To determine the impact of preoperative symptom duration on postoperative functional outcomes after cervical disc replacement (CDR) for radiculopathy.

SUMMARY OF BACKGROUND DATA

CDR has emerged as a reliable and efficacious treatment option for degenerative cervical spine pathologies. The relationship between preoperative symptom duration and outcomes after CDR is not well established.

METHODS

Patients with radiculopathy without myelopathy who underwent primary 1- or 2-level CDRs were included and divided into shorter (<6 mo) and prolonged (≥6 mo) cohorts based on preoperative symptom duration. Patient-reported outcome measures (PROMs) included neck disability index (NDI), visual analog scale (VAS) neck and arm. Changes in PROM scores and minimal clinically important difference (MCID) rates were calculated. Analyses were conducted on the early (within 3 mo) and late (6 mo-2 y) postoperative periods.

RESULTS

A total of 201 patients (43.6±8.7 y, 33.3% female) were included. In both early and late postoperative periods, the shorter preoperative symptom duration cohort experienced significantly greater change from preoperative PROM scores compared with the prolonged symptom duration cohort for NDI, VAS-Neck, and VAS-Arm. The shorter symptom duration cohort achieved MCID in the early postoperative period at a significantly higher rate for NDI (78.9% vs. 54.9%, P =0.001), VAS-Neck (87.0% vs. 56.0%, P <0.001), and VAS-Arm (90.5% vs. 70.7%, P =0.002). Prolonged preoperative symptom duration (≥6 mo) was identified as an independent risk factor for failure to achieve MCID at the latest timepoint for NDI (OR: 2.9, 95% CI: 1.2-6.9, P =0.016), VAS-Neck (OR: 9.8, 95% CI: 3.7-26.0, P <0.001), and VAS-Arm (OR: 7.5, 95% CI: 2.5-22.5, P <0.001).

CONCLUSIONS

Our study demonstrates improved patient-reported outcomes for those with shorter preoperative symptom duration undergoing CDR for radiculopathy, suggesting delayed surgical intervention may result in poorer outcomes and greater postoperative disability.

LEVEL OF EVIDENCE

Level III.

[Influence of preoperative symptom duration on effectiveness of cervical disc arthroplasty in cervical spondylotic radiculopathy patients]

Objective

To investigate the influence of preoperative symptom duration on effectiveness of cervical disc arthroplasty (CDA) in cervical spondylotic radiculopathy (CSR) patients.

Methods

The clinical data of 90 CSR patients who underwent single-segment CDA between January 2008 and March 2020 and met the selection criteria were retrospectively analyzed. Based on preoperative symptom duration, patients were divided into an early intervention group (preoperative symptom duration <24 months) and a late intervention group (preoperative symptom duration ≥24 months). There was no significant difference in baseline data between the two groups ( P>0.05), including age, gender, body mass index, smoking status, surgical segment, preoperative neck disability index (NDI), visual analogue scale (VAS) score, cervical lordosis (CL), C 2-C 7 range of motion (ROM), disc angle (DA), disc ROM (DROM), and disc intervertebral height (DIH). The early intervention group had a slightly higher preoperative Japan Orthopedic Association (JOA) score than the late intervention group ( P<0.05). Perioperative indicators such as operation time, intraoperative blood loss, and postoperative hospital stay were recorded. The changes of JOA score, NDI, and VAS score at last follow-up compared with those before operation were used to evaluate the clinical efficacy, and the imaging evaluation of CL, C 2-C 7 ROM, DA, DROM, and DIH was performed before operation, immediately after operation, and at last follow-up. The incidence of prosthesis-related complications, including heterotopic ossification (HO), anterior bone loss (ABL), and prosthesis subsidence, was also assessed at last follow-up.

Results

Patients in both groups were followed up 24-120 months, with an average of 53.4 months. There was no significant difference in operation time, intraoperative blood loss, or follow-up duration between the groups ( P>0.05). However, the late intervention group had significantly longer postoperative hospital stay compared to the early intervention group ( P<0.05). At last follow-up, there was no significant difference in the changes of JOA score, NDI, and VAS score between the two groups before and after operation ( P>0.05). During the follow-up, there was no surgical revision in the two groups, and there was no significant difference in the incidence of HO, ABL, and prosthesis subsidence between the two groups at last follow-up ( P>0.05). Imaging evaluation showed that there was no significant difference in CL, C 2-C 7 ROM, DA, DROM, and DIH between the two groups at each time point before and after operation ( P>0.05). The intra-group comparison showed that the early intervention group could maintain the immediate postoperative CL at last follow-up, while the late intervention group had recovered to the preoperative level. Additionally, the C 2-C 7 ROM, DROM, and DA had all recovered to preoperative levels at last follow-up in both groups; meanwhile, the DIH significantly increased immediately after operation and sustained until the last follow-up.

Conclusion

Preoperative symptom duration significantly affects the effectiveness of CDA in CSR patients. Patients with preoperative symptom duration ≥24 months have longer postoperative hospital stays and potentially poorer ability to maintain CL compared with patients with preoperative symptom duration <24 months.

The Impact of Preoperative Symptom Duration on Patient Outcomes After Posterior Cervical Decompression and Fusion

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

To determine if decreased preoperative symptom duration is associated with greater clinical improvement in function and myelopathic symptoms after posterior cervical decompression and fusion (PCDF).

METHODS

All patients over age 18 who underwent primary PCDF for cervical myelopathy or myeloradiculopathy at a single institution between 2014 and 2020 were retrospectively identified. Patient demographics, surgical characteristics, duration of symptoms, and preoperative and postoperative patient reported outcomes measures (PROMs) including modified Japanese Orthopaedic Association (mJOA), Neck Disability Index (NDI), Visual Analogue Scale (VAS) Neck, VAS Arm, and SF-12 were collected. Univariate and multivariate analyses were performed to compare change in PROMs and minimum clinically important difference achievement (%MCID) between symptom duration groups (< 6 months, 6 months-2 years, > 2 years).

RESULTS

Preoperative symptom duration groups differed significantly by sex and smoking status. Patients with < 6 months of preoperative symptoms improved significantly in all PROMs. Patients with 6 months-2 years of preoperative symptoms did not improve significantly in mJOA, Physical Component Scores (PCS), or NDI. Patients with > 2 years of symptoms failed to demonstrate significant improvement in mJOA, NDI, or Mental Component Scores (MCS). Univariate analysis demonstrated significantly decreased improvement in mJOA with longer symptom durations. Increased preoperative symptom duration trended toward decreased %MCID for mJOA and MCS. Regression analysis demonstrated that preoperative symptom duration of > 2 years relative to < 6 months predicted decreased improvement in mJOA and NDI and decreased MCID achievement for mJOA and MCS.

CONCLUSION

Increased duration of preoperative symptoms (> 2 years) before undergoing PCDF was associated with decreased postoperative improvement in myelopathic symptoms.

Does Symptom Duration Prior to Anterior Cervical Discectomy and Fusion for Disc Herniation Influence Patient-Reported Outcomes in a Workers' Compensation Population?

OBJECTIVE

To evaluate the influence of symptom duration before anterior cervical discectomy and fusion (ACDF) on patient-reported outcomes (PROs) in workers' compensation patients.

METHODS

A prospective registry was searched for workers' compensation patients who underwent ACDF for herniated disc. Two cohorts based on symptom duration were formed: lesser duration (LD) (<6 months) and prolonged duration (PD) (≥6 months). PROs were collected preoperatively and at 6 weeks, 12 weeks, 6 months, and 1 year postoperatively. PROs were compared within and between groups. Rates of minimum clinically important difference (MCID) were compared between groups.

RESULTS

The study included 63 patients. The LD cohort reported improvement in Patient-Reported Outcomes Measurement Information System-Physical Function (PROMIS-PF), Neck Disability Index (NDI), and visual analog scale (VAS) neck at 12 weeks and 6 months and VAS arm at all periods (all P ≤ 0.036). The LD cohort reported improvement in NDI at 12 weeks and 6 months and VAS arm at 6 weeks, 12 weeks, and 6 months (all P ≤ 0.037). Between groups, the LD cohort demonstrated superior scores in PROMIS-PF at 6 weeks, 12 weeks, and 6 months; NDI preoperatively and at 6 weeks, 12 weeks, and 6 months; VAS neck at 12 weeks; and 9-item Patient Health Questionnaire (PHQ-9) at 6 months (all P ≤ 0.045). The LD group was more likely to achieve MCID in PROMIS-PF at 12 weeks (P = 0.012). The PD group was more likely to achieve MCID in PHQ-9 at 6 months (P = 0.023).

CONCLUSIONS

Regardless of length of symptom duration before ACDF in workers' compensation patients, the patients demonstrated improvements in disability and arm pain. Patients with LD also demonstrated improvements in physical function and neck pain. Patients with LD demonstrated superior scores in physical function, pain, disability, and mental health and were more likely to achieve clinically significant improvement in physical function. Patients with PD were more likely to achieve clinically significant improvement in mental health.

Microscopic Anterior Cervical Discectomy and Fusion Versus Posterior Percutaneous Endoscopic Cervical Keyhole Foraminotomy for Single-level Unilateral Cervical Radiculopathy: A Systematic Review and Meta-analysis

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVE

The objective of this study was to compare the safety of microscopic anterior cervical discectomy and fusion (MI-ACDF) and posterior percutaneous endoscopic keyhole foraminotomy (PPEKF) in patients diagnosed with single-level unilateral cervical radiculopathy.

SUMMARY OF BACKGROUND DATA

After conservative treatment, the symptoms will be relieved in about 90% of cervical radiculopathy patients. For the other one tenth of patients, surgical treatment is needed. The overall complication rate of MI-ACDF and PPEKF ranges from 0% to 25%, and the reoperation rate ranges from 0% to 20%.

MATERIALS AND METHODS

Electronic retrieval of studies from PubMed, Embase, and Cochrane Library was performed to identify comparative or single-arm studies on MI-ACDF and PPEKF. A total of 24 studies were included in our meta-analysis by screening according to the inclusion and exclusion criteria. After data extraction and quality assessment of the included studies, a meta-analysis was performed by using the R software. The pooled incidences of efficient rate, total complication rate, and reoperation rate were calculated.

RESULTS

A total of 24 studies with 1345 patients (MI-ACDF: 644, PPEKF: 701) were identified. There was no significantly statistical difference in pooled patient effective rate (MI-ACDF: 94.3% vs. PPEKF: 93.3%, P =0.625), total complication rate (MI-ACDF: 7.1% vs. PPEKF: 4.7%, P =0.198), and reoperation rate (MI-ACDF: 1.8% vs. PPEKF: 1.1%, P =0.312). However, the common complications of the 2 procedures were different. The most common complications of MI-ACDF were dysphagia and vertebral body sinking, whereas the most common complication of PPEKF was nerve root palsy.

CONCLUSIONS

Both MI-ACDF and PPEKF can provide a relatively safe and reliable treatment for single-level unilateral cervical radiculopathy. The 2 techniques are not significantly different in terms of effective rate, total complication rate, and reoperation rate.

The Effect of Preoperative Symptom Duration on Patient-Reported Outcomes After Anterior Cervical Discectomy and Fusion in Nonmyelopathic Patients: Analyses From the Michigan Spine Surgery Improvement Collaborative (MSSIC)

BACKGROUND

The effect of preoperative symptom duration (PSD) on patient-reported outcomes (PROs) in anterior cervical discectomy and fusion (ACDF) for radiculopathy is unclear.

OBJECTIVE

To determine whether PSD is a predictor for PRO after ACDF for radiculopathy.

METHODS

The Michigan Spine Surgery Improvement Collaborative registry was queried between March, 2014, and July, 2019, for patients who underwent ACDF without myelopathy and PROs (baseline, 90 days, 1 year, 2 years). PROs were measured by numerical rating scales for neck/arm pain, Patient-Reported Outcomes Measurement Information System Short Form-Physical Function (PROMIS-PF), EuroQol-5D (EQ5D), and North American Spine Society satisfaction. Univariate analyses were used to evaluate the proportion of patients reaching minimal clinically important differences (MCID). PSD was <3 months, 3 month-1 year, or >1 years. Multiple logistic regression models were used to estimate the association between PSD and PRO reaching MCID. The discriminative ability of the model was evaluated by receiver operating characteristic curve.

RESULTS

We included 2233 patients who underwent ACDF with PSD <3 months (278, 12.4%), 3 month-1 year (669, 30%), and >1 years (1286, 57.6%). Univariate analyses demonstrated a greater proportion of patients achieving MCID in <3-month cohort for arm numerical rating scales, PROMIS-PF, EQ5D, and North American Spine Society Satisfaction. Multivariable analyses demonstrated using <3 months PSD as a reference, PSD >1 years was associated with decreased odds of achieving MCID for EQ5D (odds ratio 0.5, CI 0.32-0.80, P = .004). Private insurance and increased baseline PRO were associated with significantly higher odds for achieving PROMIS-PF MCID and EQ5D-MCID.

CONCLUSION

Preoperative symptom duration greater than 1 year in patients who underwent ACDF for radiculopathy was associated with worse odds of achieving MCID for multiple PROs.

Impact of age within younger populations on outcomes following cervical surgery in the ambulatory setting

Objective

To determine the effect of age within the younger population seen at ambulatory surgical centers on patient-reported outcome measures (PROMs) after cervical spine surgery.

Methods

Patients of age <65 years undergoing single-level anterior cervical discectomy and fusion (ACDF) or cervical disc replacement (CDR) were included. Patients were divided by mean age of initial population (46 years). PROMs included Patient-reported Outcome Measurement Information System Physical Function (PROMIS-PF), 12-Item Short-Form Physical Component Survey (SF-12 PCS), Visual Analog Scale (VAS) neck, VAS arm, Neck Disability Index (NDI) collected preoperatively and at postoperative time points up to 2 years.

Results

138 patients were included, with 66 patients <46 years. Both cohorts demonstrated improvement from preoperative baseline with regard to all studied PROMs at multiple time points postoperatively (p ≤ 0.042, all). Between groups, the older cohort demonstrated greater mean PROMIS-PF scores preoperatively and at 6 weeks (p ≤ 0.011, both), while VAS arm scores were lower in the older group at 1 year (p = 0.002), and NDI scores were lower in the older group at 6 weeks and 1 year (p < 0.027, both). Minimal Clinically Important Difference (MCID) achievement rates were greater in the younger group in PROMIS PF at 2 years (p = 0.002), and in the older group in VAS arm score at 1 year (p = 0.007).

Conclusion

Both cohorts showed significant improvement at multiple postoperative time points for all PROMs. Between groups, the older group reported more favorable physical function, VAS arm, and NDI scores at several time points. However, MCID achievement rates only significantly differed in two PROMs at singular time points. Difference in age in patients <65 years likely does not significantly affect long-term outcomes after cervical spine surgery.

Frailty as a Superior Predictor of Dysphagia and Surgically Placed Feeding Tube Requirement After Anterior Cervical Discectomy and Fusion Relative to Age

Frailty is a measure of physiological reserve that has been demonstrated to be a discriminative predictor of worse outcomes across multiple surgical subspecialties. Anterior cervical discectomy and fusion (ACDF) is one of the most common neurosurgical procedures in the United States and has a high incidence of postoperative dysphagia. To determine the association between frailty and dysphagia after ACDF and compare the predictive value of frailty and age. 155,300 patients with cervical stenosis (CS) who received ACDF were selected from the 2016-2019 National Inpatient Sample (NIS) utilizing International Classification of Disease, tenth edition (ICD-10) codes. The 11-point modified frailty index (mFI-11) was used to stratify patients based on frailty: mFI-11 = 0 was robust, mFI-11 = 1 was prefrail, mFI-11 = 2 was frail, and mFI-11 = 3 + was characterized as severely frail. Demographics, complications, and outcomes were compared between frailty groups. A total of 155,300 patients undergoing ACDF for CS were identified, 33,475 (21.6%) of whom were frail. Dysphagia occurred in 11,065 (7.1%) of all patients, and its incidence was significantly higher for frail patients (OR 1.569, p < 0.001). Frailty was a risk factor for postoperative complications (OR 1.681, p < 0.001). Increasing frailty and undergoing multilevel ACDF were significant independent predictors of negative postoperative outcomes, including dysphagia, surgically placed feeding tube (SPFT), prolonged LOS, non-home discharge, inpatient death, and increased total charges (p < 0.001 for all). Increasing mFI-11 score has better prognostic value than patient age in predicting postoperative dysphagia and SPFT after ACDF.

Comparison of Percutaneous Endoscopic Cervical Keyhole Foraminotomy versus Microscopic Anterior Cervical Discectomy and Fusion for Single Level Unilateral Cervical Radiculopathy

Objective

To compare the clinical and radiological outcomes between microscopic anterior cervical discectomy and fusion (ACDF) and percutaneous endoscopic cervical keyhole foraminotomy (PECF) for single level unilateral cervical radiculopathy.

Methods

A total of 127 patients (59 in PECF VS 68 in ACDF) were enrolled in this study from April 2016 to May 2018 with a minimum follow-up of 2 years. Clinical data including baseline data, Neck Disability Index (NDI), and Visual Analogue Scale for neck and arm (VAS-n, VAS-a) were collected and compared. Radiological evaluation such as disc height, ROM of cervical, Cobb’s angle of cervical and Cobb’s angle of operated segment was measured by two experienced radiologists in twice.

Results

There was no significant difference between the two groups in the baseline data, and hospital stay was significantly decreased in PECF group than ACDF group (P < 0.001). PECF group did not yield superior better outcomes in NDI, VAS-a and VAS-n than ACDF group except at 1-month follow-up. As for radiological outcomes, PECF group has significantly better cervical motion, cervical angle and segmental angle than ADCF group at 12- and 24-month follow-up visit (P < 0.05); however, ACDF had shown better disc height restoration and maintenance than PECF (P < 0.05). More complications including surface hematoma and swallowing difficulty were occurred in ADCF group.

Conclusion

Percutaneous endoscopic cervical keyhole foraminotomy could be the alternative method for anterior cervical discectomy and fusion in selective cases. However, the indication should be fulfilled, more studies need to be conducted to further testify the efficacy of PECF.

Impact of Prolonged Duration of Symptoms on Mental Health in Anterior Cervical Disectomy and Fusion Patients

INTRODUCTION

Prolonged duration of symptoms is associated with worse pain and disability in patients undergoing anterior cervical discectomy and fusion (ACDF). Our study aims to determine the effect of symptom duration on severity of depression among ACDF patients.

METHODS

We retrospectively reviewed a prospective surgical database from 2006 to 2019 for primary, single, or multilevel ACDF. Patients missing the duration of symptom information or patient-reported outcome measures (PROMs) were excluded. PROMs included Patient Health Questionnaire-9, 12-Item Short Form Mental Component Score, and 12-Item Veterans RAND Mental Component Score and were collected at preoperative, 6-week, 12-week, 6-month, 1-year, and 2-year timepoints. The minimum clinically important difference (MCID) was calculated using the established values. Patients were categorized based on preoperative duration of symptoms as follows: <6 months, ≥6 months and <1 year, 1 to 2 years, and >2 years. Univariate analysis was done to determine differences in demographics and perioperative characteristics. Intergroup differences in PROMs and MCID achievement were evaluated using linear regression and logistic regression, respectively.

RESULTS

Two hundred thirty-one ACDF patients included had a mean age of 49.6 years and most were male (61.0%) and nonobese (<30 kg/m2; 55.0%). The groups differed by their American Society of Anesthesiologists classification (P = 0.029), workers' compensation status (P = 0.022), and diagnosis of herniated nucleus pulposus (P = 0.010). Postoperative mental health outcomes did not significantly differ between duration groups except for Veterans Rand-12 Mental Component Score at 12 weeks (P = 0.044). MCID achievement rates did not significantly differ.

CONCLUSION

Patients undergoing ACDF largely did not demonstrate differences in mental health scores or achievement of MCID based on the duration of symptoms.

Subjective and Objective Quality-of-Life Assessment of Outcome Measures in Cervical Spine Surgery for Degenerative Changes

Cervical spine diskectomy is a commonly used procedure in degenerative disease of cervical spine surgery. However, it is difficult to assess the quality of life after this widely applied and variously modified procedure. This literature review presents cervical diskectomy results, according to various scales and measures in multidirectional surgical strategies. Using relevant databases, we tried to find the best treatment options for degenerative disk disease and the best method of quality-of-life assessment, searching for modalities that may influence the outcome.

Three-dimensional high-definition exoscope (Kestrel View II) in anterior cervical discectomy and fusion: a valid alternative to operative microscope-assisted surgery

BACKGROUND

Operative microscope (OM) has greatly advanced modern spine surgery, but remains limited by several drawbacks. Therefore, a three-dimensional (3D) high-definition (HD) exoscope (EX) (Kestrel View II, Mataka Kohli, Japan) system has been developed and used as an alternative to the OM. The aim of this study was to assess and compare the perioperative data and clinical outcomes of anterior cervical discectomy and fusion (ACDF) procedure with either an EX or OM.

METHODS

Forty-eight patients with cervical spondylotic myelopathy (CSM) underwent ACDF assisted by the EX or OM between January 2019 and December 2019. We collected and compared data on operative time, intraoperative bleeding, postoperative hospitalization stay, complications, and clinical outcomes between the two groups. The clinical outcomes were evaluated by using visual analogue scale (VAS) scores, Japanese Orthopedic Association (JOA) scores, the recovery rate of JOA scores, and Odom criteria.

RESULTS

The operative time in the EX group was significantly shorter than that in the OM group (P < 0.05). The VAS and JOA scores were significantly improved in both groups after surgery (P < 0.05). In addition, the VAS scores in the EX group were significantly lower than those in the OM group at 1 week postoperatively (P < 0.05). The good-to-excellent outcome rates were 90.48 and 88.89% in the EX group and OM group, respectively, whereas the complication occurrence rates of the EX group and OM group were 4.76 and 11.11%, respectively.

CONCLUSIONS

EX-assisted and OM-assisted ACDF resulted in similar clinical outcomes for CSM, while EX-assisted surgery may be related to a short operative time and fewer complications.

Development and Validation of Cervical Prediction Models for Patient-Reported Outcomes at 1 Year After Cervical Spine Surgery for Radiculopathy and Myelopathy

STUDY DESIGN

Retrospective analysis of prospectively collected registry data.

OBJECTIVE

To develop and validate prediction models for 12-month patient-reported outcomes of disability, pain, and myelopathy in patients undergoing elective cervical spine surgery.

SUMMARY OF BACKGROUND DATA

Predictive models have the potential to be utilized preoperatively to set expectations, adjust modifiable characteristics, and provide a patient-centered model of care.

METHODS

This study was conducted using data from the cervical module of the Quality Outcomes Database. The outcomes of interest were disability (Neck Disability Index:), pain (Numeric Rating Scale), and modified Japanese Orthopaedic Association score for myelopathy. Multivariable proportional odds ordinal regression models were developed for patients with cervical radiculopathy and myelopathy. Patient demographic, clinical, and surgical covariates as well as baseline patient-reported outcomes scores were included in all models. The models were internally validated using bootstrap resampling to estimate the likely performance on a new sample of patients.

RESULTS

Four thousand nine hundred eighty-eight patients underwent surgery for radiculopathy and 2641 patients for myelopathy. The most important predictor of poor postoperative outcomes at 12-months was the baseline Neck Disability Index score for patients with radiculopathy and modified Japanese Orthopaedic Association score for patients with myelopathy. In addition, symptom duration, workers' compensation, age, employment, and ambulatory and smoking status had a statistically significant impact on all outcomes (P < 0.001). Clinical and surgical variables contributed very little to predictive models, with posterior approach being associated with higher odds of having worse 12-month outcome scores in both the radiculopathy and myelopathy cohorts (P < 0.001). The full models overall discriminative performance ranged from 0.654 to 0.725.

CONCLUSIONS

These predictive models provide individualized risk-adjusted estimates of 12-month disability, pain, and myelopathy outcomes for patients undergoing spine surgery for degenerative cervical disease. Predictive models have the potential to be used as a shared decision-making tool for evidence-based preoperative counselling.

LEVEL OF EVIDENCE

2.

The Association of Preoperative Duration of Symptoms With Clinical Outcomes and Minimal Clinically Important Difference Following Anterior Cervical Discectomy and Fusion

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

The purpose of this study is to examine whether the time duration from symptom onset to operative treatment is associated with postoperative clinical improvement after anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

There is a paucity of literature regarding the influence of preoperative symptom duration on patient-reported outcomes (PROs) following ACDF.

METHODS

Patients who underwent primary, single-level ACDF were retrospectively reviewed and stratified according to preoperative symptom duration (<12 and ≥12 mo). Demographic and perioperative characteristics were compared using χ analysis and linear regression. Subgroup mean scores were compared and achievement of minimal clinically important difference (MCID) was assessed for the Neck Disability Index (NDI), Visual Analogue Scale (VAS) neck pain, VAS arm pain, and 12-Item Short-Form Physical Component Score.

RESULTS

A total of 109 patients underwent primary, single-level ACDF: 68 had duration of symptoms (DOS) <12 months and 41 had a DOS ≥12 months. When comparing DOS subgroup preoperative PROs, there was no preoperative difference in NDI, VAS arm or neck pain, and 12-Item Short-Form Physical Component Score. In the postoperative period, there were no significant differences in the improvement of PROs throughout the 12-month timepoint. A significantly larger proportion of the <12 months DOS cohort achieved NDI MCID at the 3-month (66.1% vs. 43.8%, P=0.039) and 6-month (76.8% vs. 53.6%, P=0.030) postoperative period.

CONCLUSIONS

Among the patient subgroups with <12 and ≥12 months DOS, there were no statistically significant differences observed in any of the measured PRO means at any timepoint. When assessing MCID, however, patients with shorter DOS (<12 mo) were observed to attain NDI MCID at the 3- and 6-month timepoints more often than patients with DOS ≥12 months. Our findings suggest that delayed surgical intervention may impair functional recovery to MCID in patients with degenerative cervical disease.

Impact of preoperative weakness and duration of symptoms on health-related quality-of-life outcomes following anterior cervical discectomy and fusion

BACKGROUND CONTEXT

The majority of patients with preoperative upper extremity weakness show improvements in motor function after anterior cervical discectomy and fusion (ACDF). Although numerous studies have examined both the extent and time course to which motor function can be expected to improve, few have shown that these improvements in motor function translate to improved health related quality of life (HRQOL) outcomes.

PURPOSE

The purpose of this study was to examine the effect of preoperative weakness and duration of symptoms on HRQOL outcomes in patients who underwent ACDF.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

Adult patients who underwent an ACDF procedure at an academic hospital from January 2015 to December 2016 by a fellowship-trained spine surgeon.

OUTCOME MEASURES

The primary outcomes of interest were HRQOL outcomes: Short Form-12 Physical/Mental Component Scores (SF-12 PCS/MCS), Neck Disability Index (NDI), and Visual Analog Scale Arm/Neck scores (VAS Arm/Neck).

METHODS

Patient demographics, surgical case characteristics, and motor strength exams were collected in patients who underwent ACDF over a 2-year period. Preoperative weakness was defined by a strength grade ≤3 (on a scale from 0 to 5) in at least one upper extremity muscle group. Multivariate linear regression analysis was performed to determine the effect of the preoperative weakness on HRQOL outcomes.

RESULTS

Of the 276 patients identified, 45 (16.3%) showed evidence of preoperative weakness, 44 (97.8%) of which showed subsequent postoperative motor improvements after ACDF. All patients reported significant improvements in all HRQOL outcome measures. Patients with preoperative weakness reported significantly worse preoperative VAS Arm (6.9 vs. 5.2; p=.01) and VAS Neck (6.1 vs. 4.8; p=.02) pain scores. Compared with patients without preoperative weakness, those with preoperative weakness reported significantly more improvement in NDI (β: -10.9; p=.001). Patients with symptoms greater than or equal to 12 months and preoperative weakness showed significantly less improvement in NDI (β: 14.8; p=.03).

CONCLUSIONS

Patients with preoperative weakness generally exhibited worse pain and HRQOL measures preoperatively, and showed greater potential for improvement after ACDF. Patients with a shorter duration of preoperative weakness had greater potential for improvement in HRQOL measures after ACDF compared with those with longer duration of symptoms. ACDF is an effective procedure to improve strength and HRQOL measures across all patient groups under appropriate indications.

Clinical outcomes for anterior cervical discectomy and fusion with silicon nitride spine cages: a multicenter study

BACKGROUND

Intervertebral spacers made of silicon nitride (Si3N4) are currently used in cervical and thoracolumbar fusion. While basic science data demonstrate several advantages of Si3N4 over other biomaterials, large-scale clinical results on its safety and efficacy are lacking. This multicenter retrospective study examined outcomes for anterior cervical discectomy and fusion (ACDF) using Si3N4 cages. Results were compared to compiled metadata for other ACDF materials.

METHODS

Pre-operative patient demographics, comorbidities, changes in visual analog scale (VAS) pain scores, complications, adverse events, and secondary surgical interventions were collected from the medical records of 860 patients who underwent Si3N4 ACDF at four surgical centers. For comparison, MEDLINE/PubMed and Google Scholar searches were performed for ACDF using other cage or spacer materials. Nine studies with 13 cohorts and 736 patients met the inclusion criteria for this control group.

RESULTS

Overall, the mean last-follow-up for all patients was 319±325 days (10.6±10.8 months), with the longest follow-up being 6.5 years. In comparison to the metadata, patients from the Si3N4 groups were older (57.9±12.2 vs. 56.8±11.1 y, P=0.06) and had higher BMI values (30.0±6.3 vs. 28.1±6.5, P<0.01), but gender and smoking were not different. The Si3N4 patients reported significant improvements in VAS pain scores at last follow-up (i.e., pre-op of 71.0±22.1 vs. follow-up of 36.4±31.5, P<0.01). Although both preoperative and last-follow-up pain scores were higher for Si3N4 patients than the control, the overall change in scores (ΔVAS) was similar. From pre-op to last-follow up, ΔVAS values were 35.4±34.3 for patients receiving the Si3N4 implants versus 34.4±27.3 for patients from the meta-analysis (P=0.56). The complication and reoperation rate for the Si3N4 and the metadata were also comparable (i.e., 7.39% and 0.31% versus 9.79% and 0%, P=0.17 and 0.25, respectively).

CONCLUSIONS

ACDF outcomes using Si3N4 implants matched the clinical efficacy of other cage biomaterials.

Does the Duration of Cervical Radicular Symptoms Impact Outcomes After Anterior Cervical Discectomy and Fusion?

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To compare clinical outcomes after anterior cervical discectomy and fusion (ACDF) based on preoperative duration of radiculopathy symptoms.

SUMMARY OF BACKGROUND DATA

There is no clear indication of when outcomes after ACDF become less effective in the setting of acute versus chronic symptoms from cervical nerve root compression.

MATERIALS AND METHODS

A retrospective cohort study of consecutive patients who underwent an ACDF between 2008 and 2015 for radiculopathy was performed. Patients were divided into 3 groups: radicular symptoms lasting for <6 months, symptoms lasting for 6-12 months, and those with symptoms for ≥12 months. Neck Disability Index (NDI) and Visual Analog Scale (VAS) scores for both the neck and arms were obtained at preoperative and final postoperative visits. Radiographs were assessed for adjacent segment degeneration, fusion, and subsidence. Bivariate and multivariate regressions were subsequently used to compare outcomes between groups.

RESULTS

A total of 379 patients were included. Patients with symptoms lasting for 6-12 months and those with symptoms lasting for ≥12 months had worse preoperative VAS neck pain compared with patients with symptoms lasting for < 6 months (P=0.000 and P=0.004, respectively). Patients with symptoms lasting for ≥12 months had worse baseline functional status compared with patients with symptoms lasting for <6 months (P=0.009). At final follow-up, there were no significant differences in VAS neck, VAS arm, or NDI between symptom duration groups. However, differences in outcomes were noted when considering the type of preoperative symptom. Patients with pain symptoms of ≥12 months had worse preoperative VAS neck (P=0.001), VAS arm (P=0.008), and NDI (P<0.001) and had significantly worse final VAS arm (P=0.019) and NDI (P=0.016) compared with patients with preoperative pain symptoms lasting for <6 months. The overall reoperation rate was 4.5%. Fusion was achieved in 97.6% of the patients, and subsidence was observed in 5.5%. There were no significant differences in the risk of adjacent segment degeneration, reoperations, fusion rates, or subsidence rates based on preoperative symptom duration.

CONCLUSIONS

Despite worse preoperative neck pain and functional status in patients with preoperative duration of symptoms >6 months, there were no differences in final clinical outcomes across groups.

Propensity-matched Comparison of Outcomes and Costs After Macroscopic and Microscopic Anterior Cervical Corpectomy Using a National Longitudinal Database

STUDY DESIGN

A retrospective analysis of national longitudinal database.

OBJECTIVE

The aim of this study was to examine the outcomes and cost-effectiveness of operating microscope utilization in anterior cervical corpectomy (ACC).

SUMMARY OF BACKGROUND DATA

The operating microscope allows for superior visualization and facilitates ACC with less manipulation of tissue and improved decompression of neural elements. However, many groups report no difference in outcomes with increased cost associated with microscope utilization.

METHODS

A longitudinal database (MarketScan) was utilized to identify patients undergoing ACC with or without microscope between 2007 and 2016. Propensity matching was performed to normalize differences between the two cohorts. Outcomes and costs were subsequently compared.

RESULTS

A total of 11,590 patients were identified for the "macroscopic" group, while 4299 patients were identified for the "microscopic" group. For the propensity-matched analysis, 4298 patients in either cohort were successfully matched according to preoperative characteristics. Hospital length of stay was found to be significantly longer in the macroscopic group than the microscopic group (1.86 nights vs. 1.56 nights, P < 0.0001). Macroscopic ACC patients had an overall higher rate of readmissions [30-day: 4.2% vs. 3.2%, odds ratio (OR) = 0.76 (0.61-0.96), P = 0.0223; 90-day: 7.0% vs. 5.9%, OR = 0.82 (0.69-0.98), P = 0.0223]. Microscopic ACC patients had a higher rate of discharge to home [86.6% vs. 92.5%, OR = 1.91 (1.65-2.21), P < 0.0001] and lower rates of new referrals to pain management [1.0% vs. 0.4%, OR = 0.42 (0.23-0.74), P = 0.0018] compared with macroscopic ACC. Postoperative complication rate was not found to be significantly different between the groups. Finally, total initial admission charges were not significantly different between the macroscopic and microscopic groups ($30,175 vs. $29,827, P = 0.9880).

CONCLUSION

The present study suggests that the use of the operating microscope for ACC is associated with decreased length of stay, readmissions, and new referrals to pain management, as well as higher rate of discharge to home.

LEVEL OF EVIDENCE

3.

Risk Factors Associated With Failure to Reach Minimal Clinically Important Difference in Patient-Reported Outcomes Following Anterior Cervical Discectomy and Fusion

Background

The minimum clinically importance difference (MCID) represents a threshold for improvements in patient-reported outcomes (PROs) that patients deem important. No previous study has comprehensively examined risk factors for failure to achieve MCID after anterior cervical discectomy and fusion (ACDF) procedures for radiculopathic symptomatology. The purpose of this study is to determine risk factors for failure to reach MCID for Neck Disability Index (NDI), Visual Analog Scale (VAS) neck pain, and VAS arm pain in patients undergoing 1- or 2-level ACDF procedures.

Methods

A surgical registry of patients who underwent primary, 1- or 2-level ACDF from 2014 to 2016 was reviewed. Rates of MCID achievement for NDI, VAS neck pain, and VAS arm pain at final follow-up were calculated based on published MCID values. Patients were then categorized into demographic and procedural categories. Bivariate regression was used to test for association of demographic and procedural characteristics with failure to reach MCID for each PRO. The final multivariate model including all demographic and procedural categories as controls was created using backward stepwise regression.

Results

Eighty-three, 84, and 77 patients were included in the analysis for VAS neck, VAS arm, and NDI, respectively. Rates of MCID achievement for VAS neck, VAS arm, and NDI were 55.4%, 36.9%, and 76.6%, respectively. On bivariate analysis, patients with Charlson Comorbidity Index (CCI) ≥ 2 were less likely to achieve MCID for NDI than patients with CCI < 2 (P = .025). On multivariate analysis, CCI ≥ 2 (P = .025) was further associated with failure to reach MCID for NDI.

Conclusions

The results of this study suggest that the majority of patients do not reach MCID for arm pain. Additionally, higher comorbidity burden as evidenced by higher CCI scores is a negative predictive factor for the achievement of MCID in neck disability following ACDF.

Level of Evidence

3.

Longer Preoperative Duration of Symptoms Negatively Affects Health-related Quality of Life After Surgery for Cervical Radiculopathy

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

Determine the effect of duration of symptoms (DOS) on health-related quality of life (HRQOL) outcomes for patients with cervical radiculopathy.

SUMMARY OF BACKGROUND DATA

The effect of DOS has not been extensively evaluated for cervical radiculopathy.

METHODS

A retrospective analysis of patients who underwent an anterior cervical decompression and fusion for radiculopathy was performed. Patients were grouped based on DOS of less than 6 months, 6 months to 2 years, and more than 2 years and HRQOL outcomes were evaluated.

RESULTS

A total of 216 patients were included with a mean follow-up of 16.0 months. There were 86, 61, and 69 patients with symptoms for less than 6 months, 6 months to 2 years, and more than 2 years, respectively. No difference in the absolute postoperative score of the patient reported outcomes was identified between the cohorts. However, in the multivariate analysis, radiculopathy for more than 2 years predicted lower postoperative Short Form-12 Physical Component Score (P = 0.037) and Short Form-12 Mental Component Score (P = 0.029), and higher postoperative Neck Disability Index (P = 0.003), neck pain (P = 0.001), and arm pain (P = 0.004) than radiculopathy for less than 6 months. Furthermore, the recovery ratios for patients with symptoms for less than 6 months demonstrated a greater improvement in NDI, neck pain, and arm pain than for 6 months to 2 years (P = 0.041; 0.005; 0.044) and more than 2 years (P = 0.016; 0.014; 0.002), respectively.

CONCLUSION

Patients benefit from spine surgery for cervical radiculopathy at all time points, and the absolute postoperative score for the patient reported outcomes did not vary based on the duration of symptoms; however, the regression analysis clearly identified symptoms for more than 2 years as a predictor of worse outcomes, and the recovery ratio was statistically significantly improved in patients who underwent surgery within 6 months of the onset of symptoms.

LEVEL OF EVIDENCE

3.

Impact of old age on patient-report outcomes and cost utility for anterior cervical discectomy and fusion surgery for degenerative spine disease

PURPOSE

With growing older population and increasing rates of cervical spinal surgery, it is vital to understand the value of cervical surgery in this population. We set forth to determine the cost utility following anterior cervical decompression and fusion (ACDF) for degenerative disease in older patients.

METHODS

Patients undergoing ACDF for degenerative diseases were enrolled into prospective longitudinal registry. Patient-reported outcomes (PROs) were recorded at baseline, 1-year, and 2-year postoperatively. Two-year medical resource utilization, missed work, and health-state values [quality-adjusted life years (QALYs)] were assessed to compute cost per QALY gained. Patients were dichotomized based on age: <65 years (younger) and ≥65 years (older) to compare the cost utility in these age groups.

RESULTS

Total 218 (87%) younger patients and 33 (13%) older patients who underwent ACDF were analyzed. Both the groups demonstrated a significant improvement in PROs 2-year following surgery. The older patients had a lower mean cumulative gain in QALYs compared to younger patients at 1 year (0.141 vs. 0.28, P = 0.05) and 2 years (0.211 vs. 0.424, P = 0.04). There was no significant difference in the mean total 2-year cost between older [$21,041 (95% CI $18,466-$23,616)] and younger [$22,669 (95% CI $$21,259-$24,079)] patients (P = 0.27). Two-year cost per QALY gained in older vs. younger patients was ($99,720/QALYs gained vs. ($53,464/QALYs gained, P = 0.68).

CONCLUSION

ACDF surgery provided a significant gain in health-state utility in older patients with degenerative cervical pathology, with a mean cumulative 2-year cost per QALY gained of $99,720/QALY. While older patients have a slightly higher cost utility compared to their younger counterparts, surgery in the older cohort does provide a significant improvement in pain, disability, and quality-of-life outcomes.

Comparison of surgical outcomes after anterior cervical discectomy and fusion: does the intra-operative use of a microscope improve surgical outcomes

BACKGROUND

The primary aim of this study was to assess and compare the complications profile as well as long-term clinical outcomes between patients undergoing an Anterior Cervical Discectomy and Fusion (ACDF) procedure with and without the use of an intra-operative microscope.

METHODS

One hundred and forty adult patients (non-microscope cohort: 81; microscope cohort: 59) undergoing ACDF at a major academic medical center were included in this study. Enrollment criteria included available demographic, surgical and clinical outcome data. All patients had prospectively collected patient-reported outcomes measures and a minimum 2-year follow-up. Patients completed the neck disability index (NDI), short-form 12 (SF-12) and visual analog pain scale (VAS) before surgery, then at 3, 6, 12, and 24 months after surgery. Clinical outcomes and complication rates were compared between both patient cohorts.

RESULTS

Baseline characteristics were similar between both cohorts. The mean ± standard deviation duration of surgery was longer in the microscope cohort (microscope: 169±34 minutes vs. non-microscope: 98±42 minutes, P<0.001). There was no significant difference between cohorts in the incidence of nerve root injury (P=0.99) or incidental durotomy (P=0.32). At 3 months post-operatively, both cohorts demonstrated similar improvement in VAS-neck pain (P=0.69), NDI (P=0.86), SF-12 PCS (P=0.84) and SF-12 MCS (P=0.75). At 2-year post-operatively, both the microscope and non-microscope cohorts demonstrated similar improvement from base line in NDI (microscope: 13.52±25.77 vs. non-microscope: 19.51±27.47, P<0.18), SF-12 PCS (microscope: 4.15±26.39 vs. non-microscope: 11.98±22.96, P<0.07), SF-12 MCS (microscope: 9.47±32.38 vs. non-microscope: 16.19±30.44, P<0.21). Interestingly at 2 years, the change in VAS neck pain score was significantly different between cohorts (microscope: 2.22±4.00 vs. non-microscope: 3.69±3.61, P<0.02).

CONCLUSIONS

Our study demonstrates that the intra-operative use of a microscope does not improve overall surgery-related outcomes, nor does it lead to superior long-term outcomes in pain and functional disability, 2 years after index surgery.

An Outcome Study of Anterior Cervical Discectomy and Fusion among Iranian Population

Background and Aim. First-line treatment strategy for managing cervical disc herniation is conservative measures. In some cases, surgery is indicated either due to signs/symptoms of severe/progressive neurological deficits, or because of persistence of radicular pain despite 12 weeks of conservative treatment. Success for treatment of cervical disc herniation using ACDF has been successfully reported in the literature. We aim to determine the outcome of ACDF in treatment of cervical disc herniation among Iranians. Methods and Materials/Patients. In a retrospective cohort study, we evaluated 68 patients who had undergone ACDF for cervical disc herniation from March 2006 to March 2011. Outcome tools were as follows: (1) study-designed questionnaire that addressed residual and/or new complaints and subjective satisfaction with the operation; (2) recent (one week prior to the interview) postoperative VAS for neck and upper extremity radicular pain; (3) Japanese Orthopaedic Association Myelopathy Evaluation Questionnaire (JOACMEQ) (standard Persian version); and (4) follow-up cervical Magnetic Resonance Imaging (MRI) and lateral X-ray. Results. With mean follow-up time of 52.93 (months) ± 31.89 SD (range: 13-131 months), we had success rates with regard to ΔVAS for neck and radicular pain of 88.2% and 89.7%, respectively. Except QOL functional score of JOAMEQ, 100% success rate for the other 4 functional scores of JOAMEQ was achieved. Conclusion. ACDF is a successful surgical technique for the management of cervical disc herniation among Iranian population.

Anterior cervical discectomy and fusion: is surgical education safe?

BACKGROUND

Operative skills are key to neurosurgical resident training. They should be acquired in a structured manner and preferably starting early in residency. The aim of this study was to test the hypothesis that the outcome and complication rate of anterior cervical discectomy and fusion with or without instrumentation (ACDF(I)) is not inferior for supervised residents as compared to board-certified faculty neurosurgeons (BCFN).

METHODS

This was a retrospective single-center study of all consecutive patients undergoing ACDF(I)-surgery between January 2011 and August 2014. All procedures were dichotomized into two groups according to the surgeon's level of experience: teaching cases (postgraduate year (PGY)-2 to PGY-6 neurosurgical residents) and non-teaching cases operated by BCFN. The primary study endpoint was patients' clinical outcome 4 weeks after surgery, categorized into a binary responder and non-responder variable. Secondary endpoints were complications, need for re-do surgery, and clinical outcome until the last follow-up.

RESULTS

After exclusion of six cases because of incomplete data, a total of 287 ACDF(I) operations were enrolled into the study, of which 82 (29.2 %) were teaching cases and 199 (70.8 %) were non-teaching cases. Teaching cases required a longer operation time (131 min (95 % confidence interval (CI) 122-141 min) vs. 102 min (95-108 min; p < 0.0001) and were associated with a slightly higher estimated blood loss (84 ml (95 % CI 56-111 ml) vs. 57 ml (95 % CI 47-66 ml); p = 0.0017), while there was no difference in the rate of intraoperative complications (2.4 vs. 1.5 %; p = 0.631). Four weeks after surgery, 92.7 and 93 % of the patients had a positive response to surgery (p = 1.000), respectively. There was no difference in the postoperative complication rate (4.9 vs. 3.0 %; p = 0.307). Around 30 % of the study patients were followed up in outpatient clinics for more than once up until a mean period of 6.4 months (95 % CI 5.3-7.6 months). At the last follow-up, the clinical outcome was similar with a 90 % responder rate for both groups (p = 0.834). In total, five patients from the teaching group and eight patients from the non-teaching group required re-do surgery (p = 0.602).

CONCLUSIONS

Short- and mid-term outcomes and complication rates following microscopic ACDF(I) were comparable for patients operated on by supervised neurosurgical residents or by senior surgeons. Our data thus indicate that a structured neurosurgical education of operative skills does not lead to worse outcomes or increase the complication rates after ACDF(I). Confirmation of the results by a prospective study is desired.