Cervical spondylotic myelopathy: National trends in the treatment and peri-operative outcomes over 10years

A Comparison of Clinical Outcomes Between Anterior Cervical Discectomy and Fusion Versus Posterior Cervical Laminoplasty for Multilevel Cervical Myelopathy

STUDY DESIGN

Retrospective Cohort.

OBJECTIVE

To compare patient-reported outcomes and surgical outcomes after anterior cervical discectomy and fusion (ACDF) versus cervical laminoplasty for multilevel cervical spondylotic myelopathy.

BACKGROUND

Treatment options for multilevel cervical spondylotic myelopathy include ACDF and cervical laminoplasty. Given that the literature has been mixed regarding the optimal approach, especially in patients without kyphosis, there is a need for additional studies investigating outcomes between ACDF and cervical laminoplasty.

METHODS

A retrospective review was conducted of adult patients undergoing 3 or 4-level surgery. Patients with preoperative kyphosis based on C2-C7 Cobb angles were excluded. The electronic medical record and institutional databases were reviewed for baseline characteristics, surgical outcomes, and patient-reported outcomes.

RESULTS

A total of 101 patients who underwent ACDF and 52 patients who underwent laminoplasty were included in the study. The laminoplasty cohort had a higher overall Charlson Comorbidity Index (3.10 ± 1.43 vs 2.39 ± 1.57, P = 0.011). Both groups had a comparable number of levels decompressed, C2-C7 lordosis, and diagnosis of myelopathy versus myeloradiculopathy. Patients who underwent laminoplasty had a longer length of stay (2.04 ± 1.15 vs 1.48 ± 0.70, P = 0.003) but readmission, complication, and revision rates were similar. Both groups had similar improvement in myelopathy scores (∆modified Japanese Orthopedic Association: 1.11 ± 3.09 vs 1.06 ± 3.37, P = 0.639). ACDF had greater improvement in Neck Disability Index (∆Neck Disability Index: -11.66 ± 19.2 vs -1.13 ± 11.2, P < 0.001), neck pain (∆Visual Analog Scale-neck: -2.69 ± 2.78 vs -0.83 ± 2.55, P = 0.003), and arm pain (∆Visual Analog Scale-arm: -2.47 ± 3.15 vs -0.48 ± 3.19, P = 0.010). These findings persisted in multivariate analysis except for Neck Disability Index.

CONCLUSION

ACDF and cervical laminoplasty appear equally efficacious at halting myelopathic progression. However, patients who underwent ACDF had greater improvements in arm pain at 1 year postoperatively. Longitudinal studies evaluating the efficacy of laminoplasty to mitigate adjacent segment disease are indicated to establish a robust risk-benefit assessment for these 2 procedures.

LEVEL OF EVIDENCE

III.

Mapping the Degenerative Cervical Myelopathy Research Landscape: Topic Modeling of the Literature

STUDY DESIGN

Topic modeling of literature.

OBJECTIVES

Our study has 2 goals: (i) to clarify key themes in degenerative cervical myelopathy (DCM) research, and (ii) to evaluate the current trends in the popularity or decline of these topics. Additionally, we aim to highlight the potential of natural language processing (NLP) in facilitating research syntheses.

METHODS

Documents were retrieved from Scopus, preprocessed, and modeled using BERTopic, an NLP-based topic modeling method. We specified a minimum topic size of 25 documents and 50 words per topic. After the models were trained, they generated a list of topics and corresponding representative documents. We utilized linear regression models to examine trends within the identified topics. In this context, topics exhibiting increasing linear slopes were categorized as "hot topics," while those with decreasing slopes were categorized as "cold topics".

RESULTS

Our analysis retrieved 3510 documents that were classified into 21 different topics. The 3 most frequently occurring topics were "OPLL" (ossification of the posterior longitudinal ligament), "Anterior Fusion," and "Surgical Outcomes." Trend analysis revealed the hottest topics of the decade to be "Animal Models," "DCM in the Elderly," and "Posterior Decompression" while "Morphometric Analyses," "Questionnaires," and "MEP and SSEP" were identified as being the coldest topics.

CONCLUSIONS

Our NLP methodology conducted a thorough and detailed analysis of DCM research, uncovering valuable insights into research trends that were otherwise difficult to discern using traditional techniques. The results provide valuable guidance for future research directions, policy considerations, and identification of emerging trends.

Laminoplasty versus laminectomy with fusion for treating multilevel degenerative cervical myelopathy

Background

Laminectomy with fusion (LF) and laminoplasty (LP) are common posterior decompression procedures used to treat multilevel degenerative cervical myelopathy (DCM). There is debate on their relative efficacy and safety for treatment of DCM. The goal of this study is to examine outcomes and costs of LF and LP procedures for DCM.

Methods

This is a retrospective review of adult patients (<18) at a single center who underwent elective LP and LF of at least 3 levels from C3-C7. Outcome measures included operative characteristics, inpatient mobility status, length of stay, complications, revision surgery, VAS neck pain scores, and changes in radiographic alignment. Oral opioid analgesic needs and hospital cost comparison were also assessed.

Results

LP cohort (n=76) and LF cohort (n=59) reported no difference in neck pain at baseline, 1, 6, 12, and 24 months postoperatively (p>.05). Patients were successfully weaned off opioids at similar rates (LF: 88%, LP: 86%). Fixed and variable costs respectively with LF cases hospital were higher, 15.7% and 25.7% compared to LP cases (p=.03 and p<.001). LF has a longer length of stay (4.2 vs. 3.1 days, p=.001). Wound-related complications were 5 times more likely after LF (13.6% vs. 5.9%, RR: 5.15) and C5 palsy rates were similar across the groups (LF: 11.9% LP: 5.6% RR: 1.8). Ground-level falls requiring an emergency department visit were more likely after LF (11.9% vs. 2.6%, p=.04).

Conclusions

When treating multilevel DCM, LP has similar rates of new or increasing axial neck pain compared to LF. LF was associated with greater hospital costs, length of stay, and complications compared to LP. LP may in fact be a less morbid and more cost-effective alternative to LF for patients without cervical deformity.

Development and External Validation of a Risk Calculator for Prediction of Major Complications and Readmission After Anterior Cervical Discectomy and Fusion

STUDY DESIGN

A retrospective, case-control study.

OBJECTIVE

We aim to build a risk calculator predicting major perioperative complications after anterior cervical fusion. In addition, we aim to externally validate this calculator with an institutional cohort of patients who underwent anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

The average age and proportion of patients with at least one comorbidity undergoing ACDF have increased in recent years. Given the increased morbidity and cost associated with perioperative complications and unplanned readmission, accurate risk stratification of patients undergoing ACDF is of great clinical utility.

METHODS

This is a retrospective cohort study of adults who underwent anterior cervical fusion at any nonfederal California hospital between 2015 and 2017. The primary outcome was major perioperative complication or 30-day readmission. We built standard and ensemble machine learning models for risk prediction, assessing discrimination, and calibration. The best-performing model was validated on an external cohort comprised of consecutive adult patients who underwent ACDF at our institution between 2013 and 2020.

RESULTS

A total of 23,184 patients were included in this study; there were 1886 cases of major complication or readmissions. The ensemble model was well calibrated and demonstrated an area under the receiver operating characteristic curve of 0.728. The variables most important for the ensemble model include male sex, medical comorbidities, history of complications, and teaching hospital status. The ensemble model was evaluated on the validation cohort (n=260) with an area under the receiver operating characteristic curve of 0.802. The ensemble algorithm was used to build a web-based risk calculator.

CONCLUSION

We report derivation and external validation of an ensemble algorithm for prediction of major perioperative complications and 30-day readmission after anterior cervical fusion. This model has excellent discrimination and is well calibrated when tested on a contemporaneous external cohort of ACDF cases.

The Difference of Sagittal Correction of Adult Subaxial Cervical Spine Surgery According to Age: A Retrospective Study

Objective

At present, the true sagittal alignment of the cervical spine is uncertain, resulting in no standard reference for subaxial cervical surgery. So, we aimed to explore the age difference of normal cervical sagittal alignment and to further investigate the mid‐and long‐term changes of sagittal alignment after subaxial cervical spine surgery.

Materials and Methods

This was a retrospective study and 1223 asymptomatic volunteers and 79 patients undergoing subaxial cervical spine surgery were retrospectively reviewed in total. Asymptomatic volunteers and patients were divided into six subgroups: 20–29, 30–39, 40–49, 50–59, 60–69 and ≥70 groups. The age difference and trend with age of cervical sagittal parameters of asymptomatic volunteers were assessed by cervical lateral radiography and analyzed by ANOVA test, and the regression equation of C2‐7 Cobb was established via multiple linear regression. Based on the C2‐7 Cobb regression equations of different ages, the theoretical value, deviation value, loss value of the C2‐7 Cobb, and JOA recovery rate of patients were calculated, and the correlation among the loss value, deviation value of the C2‐7 Cobb, and JOA recovery rate of the 79 patients was evaluated by Pearson correlation analysis.

Results

For the asymptomatic volunteers, the C0‐2 Cobb decreased gradually with increasing age. The C2‐7 Cobb, C2‐7 SVA, T1S, NT, and TIA increased gradually with increasing age. The CBVA fluctuated with increasing age. T1S demonstrated a moderate correlation with C2‐7 Cobb (r = 0.60, p < 0.01); C0‐2 Cobb, C2‐7 SVA, CBVA, and TIA demonstrated a fair correlation with C2‐7 Cobb (r = −0.30, −0.33, 0.41, 0.40, p < 0.01); age demonstrated a poor correlation with C2‐7 Cobb (r = 0.19, p < 0.01). The regression equations of C2‐7 Cobb were established using C0‐2 Cobb, C2‐7 SVA, CBVA, and T1S. For the patients with subaxial cervical spine surgery, the loss of C2‐7 Cobb was moderately correlated with the deviation of C2‐7 Cobb (r = 0.33, p < 0.01).

Conclusion

The age difference of cervical sagittal alignment was obvious, and the C2‐7 Cobb increased with age especially. The closer the postoperative C2‐7 Cobb was to the theoretical value of corresponding age, the smaller the loss of correction angle was, and the better the mid‐ and long‐term outcomes. The personalized sagittal reconstruction should be performed according to age difference for subaxial cervical spine surgery.

A Comparison of Various Surgical Treatments for Degenerative Cervical Myelopathy: A Propensity Score Matched Analysis

STUDY DESIGN

Retrospective Cohort.

OBJECTIVE

To compare the short-term outcomes for Laminoplasty, Laminectomy/fusion, and ACDF.

METHODS

We utilized a prospectively-collected, multi-center national database with a propensity score matching algorithm to compare the short-term outcomes for laminoplasty, laminectomy/fusion, and multi-level (>3) ACDF (with and without corpectomy). Bivariate analyses involved both chi-square/fisher exact test and t-test/ANOVA on perioperative factors. Multivariate analyses were performed to determined independent risk factors for short term outcomes.

RESULTS

546 patients remained after propensity score matching, with 182 patients in each cohort. ACDF required the longest operative time 188 ± 79 versus laminectomy/fusion (169 ± 75, p = 0.017), and laminoplasty (167 ± 66, p = 0.004). ACDF required the shortest hospital stay (LOS ≥ 2: ACDF 56.6%, laminoplasty 89.6%, laminectomy/fusion 93.4%, p < 0.05). ACDF had lower overall complications (ACDF 3.9%, laminoplasty 7.7%, laminectomy/fusion 11.5%, p < 0.05), mortality (ACDF 0%, laminoplasty 0.55%, laminectomy/fusion 2.2%, p < 0.05), and unplanned readmissions (ACDF 4.4%, laminoplasty 4.4%, laminectomy/fusion 9.9%, p < 0.05). No significant differences were seen in the other outcomes including DVT/PT, acute renal failure, UTI, stroke, cardiac complications, or sepsis. In the multivariate analysis, laminectomy/fusion (OR 17, reference: ACDF) and laminoplasty (OR10, reference: ACDF) were strong independent risk factors for LOS ≥ 2 days. Laminectomy/fusion (OR 3.2, reference: ACDF) was an independent predictor for any adverse events 30-days after surgery.

CONCLUSIONS

Laminectomy/fusion carries the highest risk for morbidity, mortality, and unplanned readmissions in the short-term postoperative period. Laminoplasty and ACDF cases carry similar short-term complications risks. ACDF is significantly associated with the longest operative duration and shortest LOS without an increase in individual or overall complications, readmissions, or reoperations.

Simulated bundled payments for four common surgical approaches to treat degenerative cervical myelopathy: a consideration to break the clinical equipoise

OBJECTIVE

In degenerative cervical myelopathy (DCM) pathologies in which there exists a clinical equipoise in approach selection, a randomized controlled trial found that an anterior approach did not significantly improve patient-reported outcomes compared with posterior approaches. In this era of value and bundled payment initiatives, the cost profiles of various surgical approaches will form an important consideration in decision-making. The objective of this study was to compare 90-day and 2-year reimbursements for ≥ 2-level (multilevel) anterior cervical discectomy and fusion (mACDF), anterior cervical corpectomy and fusion (ACCF), posterior cervical laminectomy and fusion (LF), and cervical laminoplasty (LP) performed for DCM.

METHODS

The IBM MarketScan research database (2005-2018) was used to study beneficiaries 30-75 years old who underwent surgery using four approaches (mACDF, ACCF, LF, or LP) for DCM. Demographics, index surgery length of stay (LOS), complications, and discharge disposition were compared. Index admission (surgeon, hospital services, operating room) and postdischarge inpatient (readmission, revision surgery, inpatient rehabilitation), outpatient (imaging, emergency department, office visits, physical therapy), and medication-related payments were described. Ninety-day and 2-year bundled payment amounts were simulated for each procedure. All payments are reported as medians and interquartile ranges (IQRs; Q1-Q3) and were adjusted to 2018 US dollars.

RESULTS

A total of 10,834 patients, with a median age of 54 years, were included. The median 90-day payment was $46,094 (IQR $34,243-$65,841) for all procedures, with LF being the highest ($64,542) and LP the lowest ($37,867). Index hospital payment was 62.4% (surgery/operating room 46.6%) and surgeon payments were 17.5% of the average 90-day bundle. There were significant differences in the index, 90-day, and 2-year reimbursements and their distribution among procedures.

CONCLUSIONS

In a national cohort of patients undergoing surgery for DCM, LP had the lowest complication rate and simulated bundled reimbursements at 90 days and 2 years postoperatively. The lowest quartile 90-day payment for LF was more expensive than median amounts for mACDF, ACCF, and LP. If surgeons encounter scenarios of clinical equipoise in practice, LP is likely to result in maximum value because it is 70% less expensive on average than LF over 90 days.

Factors Associated With Return to Work After Surgery for Degenerative Cervical Spondylotic Myelopathy: Cohort Analysis From the Canadian Spine Outcomes and Research Network

STUDY DESIGN

Retrosepctive analysis of prospectively collected data from the multicentre Canadian Surgical Spine Registry (CSORN).

OBJECTIVE

Degenerative cervical myelopathy (DCM) is the most common cause of spinal cord dysfunction in North America. Few studies have evaluated return to work (RTW) rates after DCM surgery. Our goals were to determine rates and factors associated with postoperative RTW in surgically managed patients with DCM.

METHODS

Data was derived from the prospective, multicenter Canadian Spine Outcomes and Research Network (CSORN). From this cohort, we included all nonretired patients with at least 1-year follow-up. The RTW rate was defined as the proportion of patients with active employment at 1 year from the time of surgery. Unadjusted and adjusted analyses were used to identify patient characteristics, disease, and treatment variables associated with RTW.

RESULTS

Of 213 surgically treated DCM patients, 126 met eligibility, with 49% working and 51% not working in the immediate period before surgery; 102 had 12-month follow-up data. In both the unadjusted and the adjusted analyses working preoperatively and an anterior approach were associated with a higher postoperative RTW (P < .05), there were no significant differences between the postoperative employment groups with respect to age, gender, preoperative mJOA (modified Japanese Orthopaedic Association) score, and duration of symptoms (P > .05). Active preoperative employment (odds ratio = 15.4, 95% confidence interval = 4.5, 52.4) and anterior surgical procedures (odds ratio = 4.7, 95% confidence interval = 1.2, 19.6) were associated with greater odds of RTW at 1 year.

CONCLUSIONS

The majority of nonretired patients undergoing surgery for DCM had returned to work 12 months after surgery; active preoperative employment and anterior surgical approach were associated with RTW in this analysis.

Surgical Apgar Score and Controlling Nutritional Status Score are significant predictors of major complications after cervical spine surgery

Nutritional screening scores, including Controlling Nutritional Status (CONUT) Score and Surgical Apgar Score (SAS), which reflect intraoperative hemodynamics, have been reported to be useful for predicting major postoperative complications in various kinds of surgery. We assessed independent risk factors for major complications after cervical spine surgery using those scoring measurements. We retrospectively reviewed medical records of patients who underwent cervical spine surgery at our institution from 2014 to 2019. Baseline clinical information, including the CONUT Score, and surgical factors, including the SAS, were assessed as risk factors for major postoperative complications. We analyzed 261 patients. Major postoperative complications occurred in 40 cases (15.3%). In the multivariate analysis, SAS (odds ratio [OR], 0.42; P < 0.01), CONUT (OR, 1.39; P < 0.01), and operative time (OR, 1.42; P < 0.01) were significant independent risk factors of major complications. The area under the SAS curve was 0.852 in the receiver operating characteristic curve analysis. Postoperative hospitalization duration was significantly longer in major complications group. Evaluating preoperative nutritional condition and intraoperative hemodynamics with CONUT score and SAS was useful for predicting major postoperative complications of cervical spine surgery. In addition, both scoring measurements are easily calculated, objective evaluations. Perioperative management utilizing those scoring measurements may help prevent them.

Simulated Bundled Payments for 4 Common Surgical Approaches to Treat Degenerative Cervical Myelopathy: A Consideration to Break the Clinical Equipoise

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim was to compare 90-day and 2-year reimbursements for ≥2-level anterior cervical discectomy and fusion (mACDF), anterior cervical corpectomy and fusion (ACCF), posterior laminectomy and fusion (LF) and laminoplasty (LP) done for degenerative cervical myelopathy (DCM).

SUMMARY OF BACKGROUND DATA

In DCM pathologies where there exists a clinical equipoise in approach selection, a randomized controlled trial found that an anterior approach did not significantly improve patient-reported outcomes over posterior approaches. In the era of value and bundled payments initiatives, cost profile of various approaches will form an important consideration for decision making.

MATERIALS AND METHODS

IBM MarketScan Research Database (2005-2018) was used to study beneficiaries (30-75 y) who underwent surgery (mACDF, ACCF, LF, LP) for DCM. Index hospital stay (operating room, surgeon, hospital services) and postdischarge inpatient, outpatient and prescription medication payments have been used to simulate 90-day and 2-year bundled payment amounts, along with their distribution for each procedure.

RESULTS

A total of 10,834 patients with median age of 54 years were included. The median 90-day payment was $46,094 (interquartile range: $34,243-$65,841) for all procedures, with LF being the highest ($64,542) and LP the lowest ($37,867). Index hospital was 62.4% (operating room: 46.6) and surgeon payments were 17.5% of the average 90-day bundle. There was significant difference in the index, 90-day and 2-year reimbursements and their distribution among procedures.

CONCLUSION

In a national cohort of patients undergoing surgery for DCM, LP had the lowest complication rate, and simulated bundled reimbursements at 90 days and 2 years postoperatively. The lowest quartile 90-day payment for LF was more expensive than median amounts for mACDF, ACCF, and LP. If surgeons encounter scenarios of clinical equipoise in practice, LP is likely to result in maximum value as it is on an average 70% less expensive than LF over 90 days.

Significance of Hospital Size in Outcomes of Single-Level Elective Anterior Cervical Discectomy and Fusion: A Nationwide Readmissions Database Analysis

OBJECTIVE

To elucidate risk factors for 90-day readmission in anterior cervical discectomy and fusion (ACDF) for small, medium, and large hospitals. To assess differences in length of stay, charges, and complication rates across hospitals of different size.

METHODS

A retrospective analysis was performed using elective, single-level ACDF data from 2016 to 2018 in the Healthcare Cost and Utilization Project Nationwide Readmissions Database. Elective single-level ACDF cases were stratified into 3 groups by hospital bed size (small, medium, and large). All-cause complication rates, mean charges, length of stay, and 90-day readmission rates were compared across hospital size. Frequencies of specific comorbidities were compared between readmitted and nonreadmitted patients for each hospital size. Comorbidities significant on univariate analysis were evaluated as independent risk factors for 90-day readmission for each hospital size using multivariate regression.

RESULTS

The overall 90-day readmission rate was 6.43% in 36,794 patients, and the rates for small, medium, and large hospitals were 6.25%, 6.28%, and 6.56%, respectively (P = 0.537). Length of stay increased significantly with hospital size (P < 0.001), and small hospitals had the lowest charges (P < 0.001). Although different independent predictors of 90-day readmission were identified for each hospital size, cardiac arrhythmia, chronic pulmonary disease, neurologic disorders, and rheumatic disease were identified as risk factors for hospitals of all sizes.

CONCLUSIONS

Hospital size is a determining factor for charges and length of stay associated with elective single-level ACDF. Variation in risk factors for readmission exists across hospital size in context of similar 90-day readmission rates.

Comparison of Perioperative Complications in Anterior Decompression With Fusion and Posterior Decompression With Fusion for Cervical Spondylotic Myelopathy: Propensity Score Matching Analysis Using a Nationwide Inpatient Database

STUDY DESIGN

A retrospective cohort study with a national inpatient database.

OBJECTIVE

This study aimed to research the perioperative complication rates of cervical spondylotic myelopathy (CSM) patients who underwent anterior decompression with fusion (ADF) and posterior decompression with fusion (PDF) using a large national inpatient database and propensity score matching (PSM) analysis.

SUMMARY OF BACKGROUND DATA

There are several ways to successfully achieve surgical spinal decompression in CSM patients; however, evidence of the systemic complications and reoperation rates in ADF and PDF is lacking.

MATERIALS AND METHODS

We identified patients who were hospitalized for CSM and underwent either ADF or PDF from 2010 to 2016 using the Japanese Diagnosis Procedure Combination database. In the ADF and PDF groups, we compared postoperative complications (systemic and local), medical costs during hospitalization, and mortality before and after PSM. In addition, multivariate regression analysis was performed to identify risk factors for perioperative systemic complications.

RESULTS

A total of 1013 matched pairs were made after PSM. More perioperative systemic complications were detected in the ADF group than in the PDF group (at least 1 complication: ADF vs. PDF: 15.2% vs. 12.0%, P=0.038), especially for respiratory failure (1.4% vs. 0.4%, P=0.018), pneumonia (1.9% vs. 0.5%, P=0.004), and dysphagia (3.0% vs. 1.1%, P=0.003). The costs were ~$8000 higher (P<0.001) and the length of hospital stay was almost 5 days longer (P<0.001) in the PDF group. The risk factors for perioperative systemic complications in ADF were high age, low body mass index, and preoperative respiratory disease, and the factors in PDF were high body mass index and preoperative renal disease.

CONCLUSION

More systemic complications, especially respiratory events, were more frequently observed in the ADF group, while the medical costs were higher and the hospital stay was longer in the PDF group.

LEVEL OF EVIDENCE

Level III.

Cost-Effectiveness of Peptide Enhanced Bone Graft i-Factor versus Use of Local Autologous Bone in Anterior Cervical Discectomy and Fusion Surgery

Study Design

We conducted decision analytical modeling using a Markov model to determine the ICER of i-factor compared to autograft in ACDF surgery.

Objective

The efficacy and safety of traditional anterior cervical discectomy and fusion (ACDF) surgery has improved with the introduction of new implants and compounds. Cost-effectiveness of these innovations remains an often-overlooked aspect of this effort. To evaluate the cost-effectiveness of i-FACTOR compared to autograft for patients undergoing ACDF surgery.

Methods

The patient cohort was extracted from a prospective, multicenter randomized control trial (RCT) from twenty-two North American centers. Patients randomly received either autograft (N = 154) or i-Factor (N = 165). We analyzed various real-world scenarios, including inpatient and outpatient surgical settings as well as private versus public insurances. Two primary outcome measures were assessed: cost and utility. In the base-case analysis, both health and societal system costs were evaluated. Health-related utility outcome was expressed in quality-adjusted life years (QALYs). Cost-effectiveness was expressed as an incremental cost-effectiveness ratio (ICER).

Results

In all scenarios, i-FACTOR reduced costs within the first year by 1.4% to 2.1%. The savings proved to be incremental over time, increasing to 3.7% over an extrapolated 10 years. The ICER at 90 days was $13,333 per QALY and became negative ("dominated") relative to the control group within one year and onwards. In a threshold sensitivity analysis, the cost of i-FACTOR could theoretically be increased 70-fold and still remain cost-effective.

Conclusion

The novel i-FACTOR is not only cost-effective compared to autograft in ACDF surgery but is the dominant economic strategy.

Anterior Cervical Discectomy and Fusion Versus Laminoplasty for Multilevel Cervical Spondylotic Myelopathy: A National Administrative Database Analysis

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) is effective for the treatment of single-level cervical spondylotic myelopathy (CSM). However, the data surrounding multilevel CSM have remained controversial. One alternative is laminoplasty, although evidence comparing these strategies has remained sparse. In the present report, we retrospectively reviewed the readmission and reoperation rates for patients who had undergone ACDF or laminoplasty for multilevel CSM from a national longitudinal administrative claims database.

METHODS

We queried the MarketScan Commercial Claims and Encounters database to identify patients who had undergone ACDF or laminoplasty for multilevel CSM from 2007 to 2016. The patients were stratified by operation type. Patients aged <18 years, patients with a history of tumor or trauma, and patients who had undergone anteroposterior approach were excluded from the present study.

RESULTS

A total of 5445 patients were included, of whom 1521 had undergone laminoplasty. A matched cohort who had undergone ACDF was identified. The overall 90-day postoperative complication rate was greater in the laminoplasty cohort (odds ratio, 1.48; 95% confidence interval, 1.18-1.86; P < 0.0001). The mean length of stay and 90-day readmission rates were greater in the laminoplasty cohort. The hospital and total payments of the index hospitalization were greater in the ACDF cohort, as were the total payments for ≤2 years after the index hospitalization.

CONCLUSIONS

In the present administrative claims database study, no difference was found in the reoperation rate between ACDF and laminoplasty. ACDF resulted in fewer complications and readmissions compared with laminoplasty but was associated with greater costs. Additional prospective research is required to investigate the factors driving the higher costs of ACDF in this population and the long-term clinical outcomes.

Current surgical practice for multi-level degenerative cervical myelopathy: Findings from an international survey of spinal surgeons

Degenerative cervical myelopathy (DCM) results from compression of the cervical spine cord as a result of age related changes in the cervical spine, and affects up to 2% of adults, leading to progressive disability. Surgical decompression is the mainstay of treatment, but there remains significant variation in surgical approaches used. This survey was conducted in order to define current practice amongst spine surgeons worldwide, as a possible prelude to further studies comparing surgical approaches.

METHODS

An electronic survey was developed and piloted by the investigators using SurveyMonkey. Collected data was categorical and is presented using summary statistics. Where applicable, statistical comparisons were made using a Chi-Squared test. The level of significance for all statistical analyses was defined as p < 0.05. All analysis, including graphs was performed using R (R Studio).

RESULTS

127 surgeons, from 30 countries completed the survey; principally UK (66, 52%) and North America (15, 12%). Respondents were predominantly Neurosurgeons by training (108, 85%) of whom 84 (75%) reported Spinal Surgery as the principal part of their practice. The majority indicated they selected their surgical procedure for multi-level DCM on a case by case basis (62, 49%). Overall, a posterior approach was more popular for multi-level DCM (74, 58%). Region, speciality or annual multi-level case load did not influence this significantly. However, there was a trend for North American surgeons to be more likely to favour a posterior approach.

CONCLUSIONS

A posterior approach was favoured and more commonly used to treat multi-level DCM, in an international cohort of surgeons. Posterior techniques including laminectomy, laminectomy and fusion or laminoplasty appeared to be equally popular.

Simplified Chinese version of the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire: cross-cultural adaptation, reliability, and validity for patients with cervical spondylotic myelopathy

PURPOSE

This study aimed to validate the simplified Chinese version of the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) for Chinese patients with cervical spondylotic myelopathy (CSM).

METHODS

The construct validity was conducted using confirmatory factor analysis (CFA). The convergent validity was based on factor loading, composite reliability (CR), and Pearson correlation coefficients (r). Internal consistency reliability was evaluated using Cronbach's α, test-retest reliability using intraclass correlation coefficients (ICC), and the ceiling and floor effects were also examined.

RESULTS

A total of 168 native Chinese-speaking patients were enrolled. The CFA indicated that construct validity did not meet the preset criteria to be considered as good. Except for Q 4-1, the factor loading was higher than the standard of 0.5, and the CR values ranged from 0.70 to 0.85. Strong to moderate correlations were found between other scales and the simplified Chinese JOACMEQ. The scale showed good internal consistency reliability (Cronbach's α 0.639-0.821), and test-retest reliability (ICC 0.760-0.916). Moreover, the ceiling effect was displayed from Q1 to Q4.

CONCLUSIONS

This study indicates that the simplified Chinese JOACMEQ is a reliable and valid measure of the functional status among Chinese patients with CSM.IMPLICATIONS FOR REHABILITATIONThe JOACMEQ was translated into the simplified Chinese and culturally adapted for Chinese-speaking patients with CSM for the first time.The simplified JOACMEQ demonstrated an excellent level of internal consistency and good test-retest reliability.The simplified Chinese JOACMEQ was reliable and valid for the measurement of the functional status among the patients with CSM.

Risk factors associated with reoperation in posterior cervical fusions: A large-scale retrospective analysis

OBJECTIVES

To identify risk factors for reoperation in patients who have undergone posterior cervical fusion (PCF).

PATIENTS AND METHODS

A retrospective cohort analysis was performed of patients undergoing PCF during a 12-year period at a single institution. Demographic and surgical characteristics were collected from electronic medical records. This study addressed reoperations, from all causes, of PCF. Different strategies, including the addition of anterior fusion, were also compared.

RESULTS

Of the 370 patients meeting inclusion criteria there were 44 patients (11.9 %) that required a revision and of those 5 required a second revision. The most common reasons for revision were adjacent segment disease and infection, 13 (3.5 %) and 11 patients (3.0 %), respectively. There was not a higher revision rate (for any cause) for patients who had a subaxial fusion and compared with those that included C2 or those that failed to cross the cervicothoracic junction. Of patients who required reoperation, there was a statistically significant higher fraction of smokers (p =  0.023).

CONCLUSION

The risks and benefits of posterior cervical instrumentation and fusion should be thoroughly discussed with patients. This report implicates smoking as a risk factor for all-cause reoperation in patients who have had this PCF and provides surgeons with additional data regarding this complication. When possible, preoperative optimization should include smoking cessation therapy.

The effect of renin-angiotensin system blockers on spinal cord dysfunction and imaging features of spinal cord compression in patients with symptomatic cervical spondylosis

BACKGROUND CONTEXT

Cervical spondylosis may lead to spinal cord compression, poor vascular perfusion, and ultimately, cervical myelopathy. Studies suggest a neuroprotective effect of renin-angiotensin system (RAS) inhibitors in the brain, but limited data exist regarding their impact on the spinal cord.

PURPOSE

To investigate whether RAS blockers and other antihypertensive drugs are correlated with preoperative functional status and imaging markers of cord compression in patients with symptomatic cervical spondylosis.

STUDY DESIGN

Retrospective observational study.

PATIENT SAMPLE

Individuals with symptomatic degenerative cervical stenosis who underwent surgery.

OUTCOME MEASURES

Imaging features of spinal cord compression and functional status (modified Japanese Orthopedic Association [mJOA] and Nurick grading scales).

METHODS

Two hundred sixty-six operative patients with symptomatic degenerative cervical stenosis were included. Demographic data, comorbidities, antihypertensive medications, and functional status (including mJOA and Nurick grading scales) were collected. We evaluated canal compromise, cord compromise, surface area of T2 signal cord change, and pixel intensity of signal cord change compared with normal cord on T2-weighted magnetic resonance imaging sequences.

RESULTS

Of 266 patients, 41.7% were women, 58.3% were men; median age was 57.2 years; 20.6% smoked tobacco; 24.7% had diabetes mellitus. One hundred forty-nine patients (55.8%) had hypertension, 142 (95.3%) of these were taking antihypertensive medications (37 angiotensin-II receptor blockers [ARBs], 44 angiotensin-converting enzyme inhibitors, and 61 other medications). Patients treated with ARBs displayed a higher signal intensity ratio (ie, less signal intensity change in the compressed cord area) compared with untreated patients without hypertension (p=.004). Patients with hypertension had worse preoperative mJOA and Nurick scores than those without (p<.001). In the multivariate analysis, ARBs remained an independent beneficial factor for lower signal intensity change (p=.04), whereas hypertension remained a risk factor for worse preoperative neurological status (p<.01).

CONCLUSIONS

In our study, patients with hypertension who were treated with RAS inhibitors had decreased T2-weighted signal intensity change than untreated patients without hypertension. Patients with hypertension also had worse preoperative functional status. Prospective case-control studies may deepen understanding of RAS modulators in the imaging and functional status of chronic spinal cord compression.

Perturbation-Based Balance Training in Postoperative Individuals With Degenerative Cervical Myelopathy

Degenerative cervical myelopathy (DCM) is a common aging condition caused by spinal cord compression. Individuals with DCM often presented with residual balance and functional impairments postoperatively. Perturbation-based balance training (PBT) has been shown to have positive effects on populations with neurological disorders but has yet to be investigated in DCM. The objective of this study was therefore to evaluate the effects of PBT on balance and functional performance in postoperative individuals with DCM. Fifteen postoperative individuals with DCM (DCM group) and 14 healthy adults (healthy control group) were recruited. The DCM group received a 4-weeks PBT using a perturbation treadmill. The outcome measures included mean velocity of center of pressure (COP) during quiet standing; center of mass (COM) variance and reaction time to balance perturbation during standing with forward and backward perturbation; gait speed during level ground walking; Timed Up and Go Test (TUG) and disability questionnaire scores including Visual Analog Scale, Neck Disability Index, and Lower Extremity Function of Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire. The assessments were conducted pre- and post-training postoperatively for the DCM group but only once for the healthy control group. Significant improvements were observed in the mean velocity of COP, COM variance, reaction time, gait speed, and TUG in the DCM group. Disability questionnaire scores were not significantly different after training in DCM group. For between-group comparisons, significant differences that were observed pre-training were not observed post-training. The 4-weeks PBT is a potential rehabilitation strategy for addressing balance and functional impairment in postoperative individuals with DCM. In addition, the post-training performance in the DCM group exhibited trends comparable to those of age-matched healthy controls. Furthermore, the training regimens offer a practical reference for future studies on populations with balance disorders. Future studies complemented with neurophysiological assessments could reveal more information of the underlying mechanisms of PBT.

Photogrammetric analysis: An objective measure to assess the craniocervical range of motion after cervical laminoplasty surgeries

Surgical decompression using laminoplasty is commonly performed for multilevel stenosis with cervical spondylotic myelopathy. However, the long-term effects on the craniocervical range of motion (ROM) after surgery are not well understood. This study represents the first entry into the literature of photogrammetric analysis for clinical measurement of craniocervical ROM. All patients underwent a French-door laminoplasty from 1995 to 2016 and were evaluated radiologically and with postoperative photographs (photogrammetric analysis) to measure craniocervical ROM and axial rotation. Radiographic parameters were occiput to C2 angle, C1-2 angle, C2-7 angle/cervical lordosis (CL), T1-slope (T1S), and TS-CL were measured. Chin-brow vertical angle (CBVA) was utilized for flexion and extension, while nose-turn angle (NTA) was used to assess axial rotation. Forty-four patients (mean age: 65.7 years, 50% female) had a mean follow-up of 37.9 months. Mean values in neutral, flexion, and extension were occiput to C2 = 30°, 15°, and 43°; C1-C2 = -32°, -25°, -32°; and C2-C7 = -4°, 11°, -20°, respectively. Mean CL was within 1 SD of the established -17° (±13.86°). Mean T1S and TS-CL were 33° and 30° in the neutral position, respectively. Mean radiographic full range of motion from flexion to extension was 53°. NTA towards patients' left was 48° and the right side was 45°. Mean CBVA, was -4°, mean flexion 37°, and extension -45°; full range was 81°. Global craniocervical ROM has proven to be well preserved for many years following cervical laminoplasty. Photogrammetric analysis is a cost-effective and radiation-free method, accurate for quantitative assessment of craniocervical and cervical ROM.

Value of Surgery and Nonsurgical Approaches for Cervical Spondylotic Myelopathy: WFNS Spine Committee Recommendations

Cervical spondylotic myelopathy (CSM) is a common cause of adult spinal cord dysfunction. Although the therapeutic options for moderate to severe CSM patients have been established well, the existing guidelines for therapeutic decisions in mild cases of CSM are unclear. We present a review of literature on conservative treatment and surgery for CSM and suggest general recommendations applicable in various clinical presentations and in different geographic locations across the globe, with due considerations to available resources and locally prevalent practices.

Posterior percutaneous full-endoscopic cervical laminectomy and decompression for cervical stenosis with myelopathy: a technical note

PURPOSE

Cervical stenosis with myelopathy caused by ossification of the ligamentum flavum is relatively rare, and surgical treatment is the preferred option. Previous surgical procedures usually require assisted internal fixation, while some problems may occur, such as large trauma, intraoperative bleeding, wound infection and internal fixation failure. The aim of this paper is to introduce a new minimally invasive surgical procedure for the treatment of upper cervical spinal stenosis complicated with myelopathy.

METHODS AND RESULTS

A 56-year-old male patient with cervical myelopathy (C2-3) caused by calcification of the ligamentum flavum underwent posterior percutaneous full-endoscopic cervical laminectomy and decompression (PECLD) and achieved a good clinical efficacy. A surgical incision just 1 cm in size was made, and there was little bleeding during the operation. The patient was hospitalized for 2 days and returned to work after 4 weeks. The patient's postoperative recovery of neurological function was significantly improved, the pain was obviously reduced, and the quality of life was remarkably improved. No intra- or postoperative surgical complications were encountered.

CONCLUSIONS

PECLD is an effective method for treating cervical stenosis associated with myelopathy due to ossification of the ligamentum flavum. It has the advantages of smaller trauma, less bleeding, shorter postoperative hospital stays and faster recovery. Taken together, this minimally technique can be considered as a good alternative to traditional open surgery.

Cervical spondylotic myelopathy: A two decade experience

Context Cervical myelopathy occurs as a result of compression of the cervical spinal cord. Symptomatology includes, but is not limited to, pain, weakness, paresthesias, or gait/balance difficulties. Objective To present a two-decade experience with the management of cervical myelopathy. Methods Literature was reviewed to provide current guidelines for management as well as accompanying clinical presentations. Results Surgical decompression, if necessary, may be achieved from either an anterior, a posterior, or a combined anterior-posterior (AP) approach. The indications for each approach, as well as the surgical techniques, are described. Conclusion Several etiologies may lead to cord compression and cervical myelopathy. The best vector of approach with regard to anterior versus posterior surgical intervention is still under investigation. Regardless, management via surgical decompression has been demonstrated repeatedly to improve the CSM patients' quality of life.

Ambulatory anterior cervical discectomy and fusion is associated with a higher risk of revision surgery and perioperative complications: an analysis of a large nationwide database

BACKGROUND CONTEXT

With the changing landscape of health care, outpatient spine surgery is being more commonly performed to reduce cost and to improve efficiency. Anterior cervical discectomy and fusion (ACDF) is one of the most common spine surgeries performed and demand is expected to increase with an aging population.

PURPOSE

The objective of this study was to determine the nationwide trends and relative complication rates associated with outpatient ACDF.

STUDY DESIGN/SETTING

This is a large-scale retrospective case control study.

PATIENT SAMPLE

The patient sample included Humana-insured patients who underwent one- to two-level ACDF as either outpatients or inpatients from 2011 to 2016 OUTCOME MEASURES: The outcome measures included incidence and the adjusted odds ratio (OR) of postoperative medical and surgical complications within 1 year of the index surgery.

MATERIALS AND METHODS

A retrospective review was performed of the PearlDiver Humana insurance records database to identify patients undergoing one- to two-level ACDF (Current Procedural Terminology [CPT]-22551 and International Classification of Diseases [ICD]-9-816.2) as either outpatients or inpatients from 2011 to 2016. The incidence of perioperative medical and surgical complications was determined by querying for relevant ICD and CPT codes. Multivariate logistic regression adjusting for age, gender, and Charlson Comorbidity Index was used to calculate ORs of complications among outpatients relative to inpatients undergoing ACDF.

RESULTS

Cohorts of 1,215 patients who underwent outpatient ACDF and 10,964 patients who underwent inpatient ACDF were identified. The median age was in the 65-69 age group for both cohorts. The annual relative incidence of outpatient ACDF increased from 0.11 in 2011 to 0.22 in 2016 (R²=0.82, p=.04). Adjusting for age, gender, and comorbidities, patients undergoing outpatient ACDF were more likely to undergo revision surgery for posterior fusion at both 6 months (OR 1.58, confidence interval [CI] 1.27-1.96, p<.001) and 1 year (OR 1.79, CI 1.51-2.13, p<.001) postoperatively. Outpatient ACDF was also associated with a higher likelihood of revision anterior fusion at 1 year postoperatively (OR 1.46, CI 1.26-1.70, p<.001). Among medical complications, postoperative acute renal failure was more frequently associated with outpatient ACDF than inpatient ACDF (OR 1.25, CI 1.06-1.49, p=.010). Adjusted rates of all other queried surgical and medical complications were comparable.

CONCLUSIONS

Outpatient ACDF is increasing in frequency nationwide over the past several years. Nationwide data demonstrate a greater risk of perioperative surgical complications, including revision anterior and posterior fusion, as well as a higher risk of postoperative acute renal failure. Candidates for outpatient ACDF should be counseled and carefully selected to reduce these risks.

Cervical Spinal Fusion: 16-Year Trends in Epidemiology, Indications, and In-Hospital Outcomes by Surgical Approach

BACKGROUND

The rate of cervical spinal fusion has been increasing significantly. However, there is a paucity of literature describing trends based on surgical approach using complete population databases. We investigated the approach-based trends in epidemiology, indications, and in-hospital outcomes of cervical spinal fusion.

METHODS

New York's Statewide Planning and Research Cooperative System database was queried to identify patients who underwent primary subaxial cervical fusion from 1997 to 2012. Demographic and clinical information was obtained. Subgroup analyses were performed based on surgical approach: anterior (A), posterior (P), and circumferential (C).

RESULTS

A total of 87,045 cervical fusions were included. Over the study period, the population-adjusted annual fusion rate increased from 23.7 to 50.6 per 100,000 population (P < 0.001). A fusion was most common (85.2%), followed by P (12.3%), and C (2.5%). Mean ages were 49.8 ± 11.9, 59.9 ± 15.2, and 55.1 ± 14.5 years (P < 0.001), respectively. Although rates remained steady among younger patients, they increased for older patients. Overall, degenerative conditions were the predominant indications for surgery and increased in rate over time. The mean length of stay was: A, 3.1 ± 10.5; P, 9.1 ± 14.1; and C, 14.1 ± 22.5 days (P < 0.001). Rates of in-hospital complications were A, 3.0%; P, 10.5%; and C, 18.9% (P < 0.001), and mortality was A, 0.3%, P, 1.8%, and C, 2.5% (P < 0.001).

CONCLUSIONS

The rate of subaxial spinal fusions increased 114% from 1997 to 2012 in New York State. Rates remained stable in younger patients but increased in the older population. Preoperative indications and postoperative courses differed significantly among the various approaches, with patients undergoing anterior fusion having better short-term outcomes.