Long Term Societal Costs of Anterior Discectomy and Fusion (ACDF) versus Cervical Disc Arthroplasty (CDA) for Treatment of Cervical Radiculopathy

Outcomes Following Two-Level Cervical Disc Arthroplasty Relative to Two-Level Anterior Cervical Discectomy

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate postoperative adverse events, readmissions, and 5-year survival to reoperation for 2-level cervical disc arthroplasty (CDA) relative to 2-level anterior cervical discectomy and fusion (ACDF).

BACKGROUND

CDA and ACDF are both treatment options for degenerative cervical spine pathology. Relative to ACDF, CDA is a relatively novel treatment option, and limited research exists comparing outcomes between 2-level CDA and 2-level ACDF.

PATIENTS AND METHODS

Patients undergoing 2-level CDA or 2-level ACDF were isolated from the PearlDiver M165Ortho database. These 2 cohorts were matched 1:1 based on patient age, sex, and Elixhauser Comorbidity Index scores. The odds of 90-day postoperative adverse events were compared between the two groups by multivariable analysis. Overall cost-of-care for the first 90 days postoperatively and 5-year survival to cervical spine reoperation were then assessed.

RESULTS

Of the 2-level cases identified, only 3.9% had CDA, and the rest had ACDF. After matching, there were 4224 patients in each of the study groups. With controlling for patient age, sex, and Elixhauser Comorbidity Index on multivariable analysis, patients undergoing 2-level CDA had significantly lower odds of experiencing 90-day dysphagia [odds ratio (OR): 0.60, P < 0.0001 driving aggregated any adverse event (OR: 0.65, P < 0.0001)] and readmission (OR: 0.69, P = 0.0002). The median 90-day cost of care was greater for patients undergoing 2-level ACDF ($4776.00 vs . $3191.00, P < 0.0001). No significant difference in 5-year survival to cervical spine reoperation was identified ( P = 0.7).

CONCLUSIONS

Relative to patients undergoing 2-level ACDF, patients undergoing 2-level CDA were found to have significantly lower odds of 90-day readmissions and minor adverse events (dysphagia), while rates of major adverse events (pulmonary embolism, deep vein thrombosis, sepsis, etc .) were comparable between the groups. Further, patients undergoing CDA had lower cost of overall care, but no difference in 5-year survival to cervical spine reoperation. Thus, it may be appropriate to further consider CDA when 2-level surgery is pursued.

Cervical Disc Arthroplasty Versus Anterior Cervical Discectomy and Fusion in the Treatment of Degenerative Cervical Myelopathy: Patient Characteristics and Surgical Outcomes in a National Administrative Database

Study DesignA retrospective cohort utilizing the PearlDiver Patient Claims Database.ObjectiveCervical disc arthroplasty (CDA) is accepted treatment for cervical radiculopathy; however, it may also be safe and effective in myelopathy. Thus, we compared clinical characteristics and outcomes in patients undergoing CDA and anterior cervical discectomy and fusion (ACDF) for degenerative cervical myelopathy (DCM) specifically.MethodsPatients undergoing CDA or ACDF between 2015-2019 were identified with follow-up through 2021. Univariate and multivariable analyses were performed to identify factors associated with either procedure. Reoperation rates were compared using propensity-matched analysis.ResultsWe identified n = 2391 CDA and n = 50 845 ACDF procedures for DCM. Factors favoring CDA included: female sex, younger age, lower CCI, lower incidence of obesity, osteoporosis, diabetes, or smoking (P ≤ .001); remaining significant after multivariable logistic regression except for sex (P = .06). Single-level surgery was more predictive for undergoing CDA. CDA patients had lower 90-day readmissions, complications, and lower opioid utilization. The overall reoperation rate was 5%. Predictors of reoperation included: male sex, younger age, greater CCI, obesity, osteoporosis, diabetes, smoking, and multi-level surgery; all remaining significant after multivariable analysis except for diabetes (P = .23) and CCI (P = .05). After propensity-matching CDA and ACDF patients (n = 2391), there was no difference in re-operation rates (P = .47).ConclusionsCDA patients were healthier (less obesity, smoking, diabetes, better CCI) and represented 4.5% of anterior procedures for DCM. In univariate analysis, readmission rates, medical complications, and opioid use were lower in CDA patients, despite a similar reoperation rate. Considering these findings, CDA might be used very selectively for DCM.

Health Care Costs Following Anterior Cervical Discectomy and Fusion or Cervical Disc Arthroplasty

STUDY DESIGN

Observational cohort study.

OBJECTIVE

To describe the postoperative costs associated with both anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) in the two-year period following surgery.

SUMMARY OF BACKGROUND DATA

CDA has become an increasingly common alternative to ACDF for the treatment of cervical disc disorders. Although a number of studies have compared clinical outcomes between both procedures, much less is known about the postoperative economic burden of each procedure.

MATERIALS AND METHODS

By analyzing a commercial insurance claims database (Marketscan, Merative), patients who underwent one-level or two-level ACDF and CDA procedures between January 1, 2017 and December 31, 2017 were identified and included in the study. The primary outcome was the cost of payments for postoperative management in the two-year period following ACDF or CDA. Identified postoperative interventions included in the study were: (i) physical therapy, (ii) pain medication, (iii) injections, (iv) psychological treatment, and (iv) subsequent spine surgeries.

RESULTS

Totally, 2304 patients (age: 49.0±9.4 yr; male, 50.1%) were included in the study. In all, 1723 (74.8%) patients underwent ACDF, while 581 (25.2%) underwent CDA. The cost of surgery was similar between both groups (ACDF: $26,819±23,449; CDA: $25,954±20,620; P =0.429). Thirty-day, 90-day, and two-year global costs were all lower for patients who underwent CDA compared with ACDF ($31,024 vs. $34,411, $33,064 vs. $37,517, and $55,723 vs. $68,113, respectively).

CONCLUSION

Lower two-year health care costs were found for patients undergoing CDA compared with ACDF. Further work is necessary to determine the drivers of these findings and the associated longer-term outcomes.

Cost-effectiveness of anterior surgical decompression surgery for cervical degenerative disk disease: a systematic review of economic evaluations

PURPOSE

No clear consensus exists on which anterior surgical technique is most cost-effective for treating cervical degenerative disk disease (CDDD). One of the most common treatment options is anterior cervical discectomy with fusion (ACDF). Anterior cervical discectomy with arthroplasty (ACDA) was developed in an effort to reduce the incidence of clinical adjacent segment pathology and associated additional surgeries by preserving motion. This systematic review aims to evaluate the evidence regarding the cost-effectiveness of anterior surgical decompression techniques used to treat radiculopathy and/or myelopathy caused by CDDD.

METHODS

The search was conducted in PubMed, EMBASE, Web of Science, CINAHL, EconLit, NHS-EED and the Cochrane Library. Studies were included if healthcare costs and utility or effectivity measurements were mentioned.

RESULTS

A total of 23 studies were included out of the 1327 identified studies. In 9 of the 13 studies directly comparing ACDA and ACDF, ACDA was the most cost-effective technique, with an incremental cost effectiveness ratio ranging from $2.900/QALY to $98.475/QALY. There was great heterogeneity between the costs of due to different in- and exclusion criteria of costs and charges, cost perspective, baseline characteristics, and calculation methods. The methodological quality of the included studies was moderate.

CONCLUSION

The majority of studies report ACDA to be a more cost-effective technique in comparison with ACDF. The lack of uniform literature impedes any solid conclusions to be drawn. There is a need for high-quality cost-effectiveness research and uniformity in the conduct, design and reporting of economic evaluations concerning the treatment of CDDD.

TRIAL REGISTRATION

PROSPERO Registration: CRD42020207553 (04.10.2020).

Anterior Cervical Discectomy and Fusion Versus Cervical Disc Arthroplasty: A Comparison of National Trends and Outcomes

OBJECTIVE

Anterior cervical discectomy and fusion (ACDF) has been considered the standard treatment for degenerative cervical disc disease; however, recent trials have shown comparable outcomes with cervical disc arthroplasty (CDA). This study aimed to observe disparities in treatment paradigms of single-level cervical disc diseases and compare inpatient outcomes between procedures.

METHODS

A retrospective cohort of patients treated for single-level cervical disc herniation or degeneration without myelopathy was queried from the Nationwide Inpatient Sample spanning 2012-2015. Multivariate logistic regression was performed to assess the effects of demographics, temporality of admission, and hospital characteristics on odds of receiving CDA versus ACDF. Propensity-score matching was performed to compare cost, length of stay (LOS), non-home discharge, and inpatient complications.

RESULTS

In total, 1028 CDAs and 44,374 ACDFs were performed for single-level cervical disc disease during 2012-2015. Matched comparison showed that while non-home discharges were not different between CDA and ACDF (P = 0.248), patients who received CDA had a 0.19-day shorter LOS (P < 0.001) and $4694 greater total cost (P < 0.001). There were no statistically significant differences in inpatient complication rates. Multivariate analysis showed that patients in the 26th-50th percentile, 51st-75th percentile, and 76th-100th percentile of median household income had greater odds of CDA compared with patients in the 0-25th percentile (odds ratio [OR] 1.35, P = 0.003; OR 1.31, P = 0.013; OR 1.34, P = 0.011, respectively). Patients with private insurance had greater odds of receiving CDA compared with patients on Medicare (OR 1.91, P < 0.001).

CONCLUSIONS

CDA was associated with shorter LOS but greater costs compared with ACDF. Patients with greater median income and private insurance were more likely to receive CDA.

The Impact of Non-Elective Admission on Cost of Care and Length of Stay in Anterior Cervical Discectomy and Fusion: A Propensity-Matched Analysis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate the impact of admission status on patient outcomes and healthcare costs in anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

Undergoing ACDF non-electively has been associated with higher patient comorbidity burdens. However, the impact of non-elective status on the total cost of hospital stay has yet to be quantified.

METHODS

Patients undergoing ACDF at a single institution were placed into elective or non-elective cohorts. Propensity score-matching analysis in a 5:1 ratio controlling for insurance type and comorbidities was used to minimize selection bias. Demographics were compared by univariate analysis. Cost of care, length of stay (LOS), and clinical outcomes were compared between groups using multivariable linear and logistic regression with elective patients as reference cohort. All analyses controlled for sex, preoperative diagnosis, elixhauser comorbidity index (ECI), age, length of surgery, number of segments fused, and insurance type.

RESULTS

Of 708 patients in the final ACDF cohort, 590 underwent an elective procedure and 118 underwent a non-elective procedure. The non-elective group was significantly younger (53.7 vs. 49.5 yr; P = 0.0007). Cohorts had similar proportions of private versus public health insurance, although elective had higher rates of commercial insurance (39.22% vs. 15.25%; P < 0.0001) and non-elective had higher rates of managed care (32.77% vs. 56.78%; P < 0.0001). Operation duration was significantly longer in non-elective patients (158 vs. 177 minutes; P = 0.01). Adjusted analysis also demonstrated that admission status independently affected cost (+$6877, 95% confidence interval [CI]: $4906-$8848; P < 0.0001) and LOS (+4.9 days, 95% CI: 3.9-6.0; P < 0.0001) for the non-elective cohort. The non-elective cohort was significantly more likely to return to the operating room (OR: 3.39; 95% CI: 1.37-8.36, P = 0.0008) and experience non-home discharge (OR: 10.95; 95% CI: 5.00-24.02, P < 0.0001).

CONCLUSION

Patients undergoing ACDF non-electively had higher cost of care and longer LOS, as well as higher rates of postoperative adverse outcomes.Level of Evidence: 3.

Comorbidities associated with cervical spine degenerative disc disease

Determining important links between medical comorbidities and cervical spine degenerative disc disease (DDD) will help elucidate pathomechanisms of disc degeneration. Electronic medical records and magnetic resonance imaging were retrospectively reviewed to evaluate 799 patients assessed for cervical spine pathology. Bivariate analysis identified older age, diabetes, ASA class, cancer, COPD, depression, hypertension, hypothyroidism, Medicare status, peripheral vascular disease, history of previous cervical spine surgery, smoking, and lower median household income as having strong associations with increased cumulative grade of cervical spine DDD. This study provides evidence suggesting aging and accumulation of medical comorbidities influence severity of cervical spine DDD.

Financial Aspects of Cervical Disc Arthroplasty: A Narrative Review of Recent Literature

Recently, there has been significant interest in understanding the cost-effectiveness of treatments in spine surgery as health care systems in the United States move toward value-based care and alternative payment models. Previous studies have shown comparable outcomes of cervical disc arthroplasty (CDA) and anterior cervical discectomy fusion; however, there is a lack of consensus on the cost-effectiveness of CDA to support full adoption. Evidence of the limitations of these cost-analysis studies also exists in the literature, including industry funding, potential selection bias, and varying methods of calculating value. The goal of this narrative review is to provide an overview of the cost-effectiveness of CDA compared with anterior cervical discectomy and fusion, and potential limitations with cost-analysis studies in spine surgery.

Effect of Myelopathy on Early Clinical Improvement After Cervical Disc Replacement: A Study of a Local Patient Cohort and a Large National Cohort

Objective

Cervical disc replacement (CDR) is an effective long-term treatment for both cervical radiculopathy and myelopathy. However, there may be unique differences in the early postoperative clinical improvement for patients with and without myelopathy. In addition, previous studies using CDR to treat cervical myelopathy were underpowered to determine risk factors for relatively postoperative medical complications.

Methods

Two different cohorts were studied. A local cohort of patients undergoing CDR by a single surgeon was utilized to study the early postoperative course of clinical improvement. In addition, a national cohort of patients undergoing CDR in the 2015 and 2016 National Surgical Quality Improvement Program database was utilized to study differences in postoperative medical complications after CDR. Patients with a preoperative diagnosis of cervical myelopathy were identified in both cohorts, and perioperative outcomes and complications were compared to patients without myelopathy.

Results

A total of 43 patients undergoing CDR were included in the institutional cohort, of those 16 patients (37% of cohort) had a preoperative diagnosis of cervical myelopathy. A total of 3,023 patients undergoing CDR were included in the national cohort, of those 411 (13% of cohort) had a preoperative diagnosis of cervical myelopathy. In the institutional cohort, the nonmyelopathy group had a lower initial Neck Disability Index (NDI) and saw a faster improvement in NDI by 2 weeks postoperative. However, at 24 weeks there was no significant difference between groups in terms of NDI. Interestingly, only the nonmyelopathy cohort had a significant improvement in modified Japanese Orthopaedic Association score by 6 weeks (p<0.05). In the national cohort, myelopathy was associated with longer operative time and length of stay (p<0.05). However, there was no significant difference in perioperative complications (p>0.05) between myelopathy and nonmyelopathy patients.

Conclusion

Significant improvements in NDI, visual analogue scale (VAS)-arm pain, and VAS-neck pain are seen in both myelopathy and nonmyelopathy populations undergoing CDR by 6 weeks postoperatively. However, nonmyelopathy populations improve faster by 2 weeks postoperatively. In the national cohort analysis, medical complications were similarly low in both myelopathy and nonmyelopathy groups.

What Are the Costs of Cervical Radiculopathy Prior to Surgical Treatment?

STUDY DESIGN

Retrospective, observational study.

OBJECTIVE

To examine the costs associated with nonoperative management (diagnosis and treatment) of cervical radiculopathy in the year prior to anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

While the costs of operative treatment have been previously described, less is known about nonoperative management costs of cervical radiculopathy leading up to surgery.

METHODS

The Humana claims dataset (2007-2015) was queried to identify adult patients with cervical radiculopathy that underwent ACDF. Outcome endpoint was assessment of cumulative and per-capita costs for nonoperative diagnostic (x-rays, computed tomographic [CT], magnetic resonance imaging [MRI], electromyogram/nerve conduction studies [EMG/NCS]) and treatment modalities (injections, physical therapy [PT], braces, medications, chiropractic services) in the year preceding surgical intervention.

RESULTS

Overall 12,514 patients (52% female) with cervical radiculopathy underwent ACDF. Cumulative costs and per-capita costs for nonoperative management, during the year prior to ACDF was $14.3 million and $1143, respectively. All patients underwent at least one diagnostic test (MRI: 86.7%; x-ray: 57.5%; CT: 35.2%) while 73.3% patients received a nonoperative treatment. Diagnostic testing comprised of over 62% of total nonoperative costs ($8.9 million) with MRI constituting the highest total relative spend ($5.3 million; per-capita: $489) followed by CT ($2.6 million; per-capita: $606), x-rays ($0.54 million; per-capita: $76), and EMG/NCS ($0.39 million; per-capita: $467). Conservative treatments comprised of 37.7% of the total nonoperative costs ($5.4 million) with injections costs constituting the highest relative spend ($3.01 million; per-capita: $988) followed by PT ($1.13 million; per-capita: $510) and medications (narcotics: $0.51 million, per-capita $101; gabapentin: $0.21 million, per-capita $93; NSAIDs: 0.107 million, per-capita $47), bracing ($0.25 million; per-capita: $193), and chiropractic services ($0.137 million; per-capita: $193).

CONCLUSION

The study quantifies the cumulative and per-capital costs incurred 1-year prior to ACDF in patients with cervical radiculopathy for nonoperative diagnostic and treatment modalities. Approximately two-thirds of the costs associated with cervical radiculopathy are from diagnostic modalities. As institutions begin entering into bundled payments for cervical spine disease, understanding condition specific costs is a critical first step.

LEVEL OF EVIDENCE

3.

Evaluation of Current Trends in Treatment of Single-level Cervical Radiculopathy

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVES

The main objectives of this study were to identify epidemiological trends, differences, and complications in patients undergoing surgical treatment for single-level cervical radiculopathy (SLCR).

SUMMARY OF BACKGROUND DATA

SLCR that fails nonoperative management is effectively treated with either anterior cervical discectomy and fusion (ACDF), cervical disc replacement (CDR), or posterior cervical foraminotomy (PCF). Although studies have shown that all 3 options are clinically effective, trends in usage, differences in patient population, and differences in complications remain unknown.

MATERIALS AND METHODS

Patients who underwent either ACDF, CDR, or PCF in the treatment of SLCR from 2010 to 2016 were retrospectively reviewed using the National Surgical Quality Improvement Program (NSQIP) database. Demographic data consisted of sex, age, ASA class, body mass index, and inpatient/outpatient status. Complications included surgical site infection, pneumonia, reintubation, pulmonary embolism, deep vein thrombosis, readmissions, reoperations, operating time, and hospital length of stay. Utilization trends by year among the 3 procedures were also analyzed.

RESULTS

A total of 1102 patients with SLCR treated with single-level ACDF, CDR, or PCF were identified in NSQIP from 2010 to 2016. There was a relative increase in the number of CDR procedures (7.7%-16.1%) and a corresponding decrease in PCF procedures (20.3%-10.6%) without a significant effect on ACDF procedures (72.0%-73.3%). Patients who underwent CDR were younger and in a lower ASA class than those undergoing ACDF or PCF. Patients undergoing PCF were more likely to be treated as an outpatient. PCF procedures also had the shortest operating time and hospital length of stay. There were no significant differences in complications among the 3 procedures. Moreover, there were no significant trends in demographics or outcome measures.

CONCLUSIONS

ACDF remains the most common surgical treatment for patients with SLCR, and its utilization has remained consistent. Meanwhile, the increased utilization of CDR for the treatment of SLCR has resulted in a corresponding decrease in the utilization of PCF.

Evidence-based use of arthroplasty in cervical degenerative disc disease

INTRODUCTION

Cervical disc arthroplasty (CDA) was developed to decrease the rate of symptomatic adjacent-level disease while preserving motion in the cervical spine.

METHODS

The objectives of this paper are to provide criteria for proper patient selection as well as to present a comprehensive literature review of the current evidence for CDA, including randomized studies, the most recent meta-analysis findings, and long-term follow-up clinical trials as well.

RESULTS

Currently, there are several prospective randomized controlled studies of level I of evidence attesting to the safety and efficacy of CDA in the management of cervical spondylotic disease (CSD) for one- or two-level degenerative diseases. These as well as recent meta-analyses suggest that CDA is potentially similar or even superior to anterior cervical discectomy and fusion (ACDF) when considering several outcomes, including dysphagia and re-operation rate over medium-term follow-up. Less robust studies have also reported satisfactory clinical and radiological outcomes of CDA for hybrid procedures (ACDF combined with CDA), non-contiguous disease, and even for multilevel disease (more than 2 levels).

CONCLUSIONS

Based on this evidence we conclude that CDA is a safe and effective alternative to ACDF in properly selected patients for one- or two-level diseases. Defining superiority of specific implants and detailing optimal surgical indications will require further well-designed long-term studies.

Cervical Artificial Disc Replacement Versus Fusion for Cervical Degenerative Disc Disease: A Health Technology Assessment

BACKGROUND

Cervical degenerative disc disease is a multifactorial condition that begins with deterioration of the intervertebral disc and results in further degeneration within the spine involving the facet joints and ligaments. This health technology assessment examined the effectiveness, safety, durability, and cost-effectiveness of cervical artificial disc replacement (C-ADR) versus fusion for treating cervical degenerative disc disease.

METHODS

We performed a systematic literature search of the clinical evidence comparing C-ADR with fusion. We assessed the risk of bias in each study and the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We performed a systematic review of the economic literature and assessed the cost-effectiveness of C-ADR compared with fusion. We also estimated the budget impact of publicly funding C-ADR in Ontario over the next 5 years. To contextualize the potential value of C-ADR, we spoke with people with cervical degenerative disc disease.

RESULTS

Eight studies of C-ADR for one-level cervical degenerative disc disease and two studies of C-ADR for two-level disease satisfied the criterion of statistical noninferiority compared with fusion on the primary outcome of 2-year overall treatment success (GRADE: Moderate). In two studies of C-ADR for two-level disease, C-ADR was statistically superior to fusion surgery for the same primary outcome (GRADE: Moderate). C-ADR was also noninferior to fusion for perioperative outcomes (e.g., operative time, blood loss), patient satisfaction, and health-related quality of life (GRADE: Moderate). C-ADR was superior to fusion for recovery and return to work, had higher technical success, and had lower rates of re-operation at the index site (GRADE: Moderate). C-ADR also maintained motion at the index-treated cervical level (GRADE: Moderate), but evidence was insufficient to determine if adjacent-level surgery rates differed between C-ADR and fusion. Current evidence is also insufficient to determine the long-term durability of C-ADR.The primary economic analysis shows that C-ADR is likely to be cost-effective compared with fusion for both one-level ($11,607/quality-adjusted life-year [QALY]) and two-level ($16,782/QALY) degeneration. Various sensitivity and scenario analyses confirm the robustness of the results. The current uptake for one-level and two-level C-ADR in Ontario is about 8% of the total eligible. For one-level involvement, the estimated net budget impact increases from $7,243 (18 procedures) in the first year to $395,623 (196 procedures) in the fifth year following public funding, for a total budget impact over 5 years of $916,326. For two-level involvement, the corresponding values are $5,460 (7 procedures) in the first year and $283,689 (76 procedures) in the fifth year, for an estimated total budget impact of $705,628 over 5 years.People with cervical degenerative disc disease reported that symptoms of pain and numbness can have a negative impact on their quality of life. People with whom we spoke had tried a variety of treatments with minor success; surgery was perceived as the most effective and permanent solution. Those who had undergone C-ADR spoke positively of its impact on their quality of life and ability to move their neck after surgery. The limited availability of C-ADR in Ontario was viewed as a barrier to receiving this treatment.

CONCLUSIONS

For carefully selected patients with cervical degenerative disc disease, C-ADR provides patient-important and statistically significant reductions in pain and disability. Further, unlike fusion, C-ADR allows people to maintain relatively normal cervical spine motion.Compared with fusion, C-ADR appears to represent good value for money for adults with one-level cervical degenerative disc disease ($11,607/QALY) and for adults with two-level disease ($16,782/QALY). In Ontario, publicly funding C-ADR could result in total additional costs of $916,326 for one-level procedures and $705,628 for two-level procedures over the next 5 years.People with whom we spoke who had undergone C-ADR surgery spoke positively of its impact on their quality of life and ability to move their neck after surgery. The limited availability of C-ADR in Ontario was viewed as a barrier to receiving this treatment.

Value of Cervical Disk Arthroplasty

Over the last decade, several of the Food and Drug Administration-regulated investigational device exemption (IDE) trials have compared multiple cervical disk arthroplasty (CDA) devices to anterior cervical decompression and fusion (ACDF) showing comparable and even superior patient-reported outcomes. CDA has been an increasingly attractive option because of the positive outcomes and the motion-preserving technology. However, with the large burden that health care expenditures place on the economy, the focus is now on the value of treatment options. Cost-effectiveness studies assess value by evaluating both outcomes and cost, and recently several have been conducted comparing CDA and ACDF. The results have consistently shown that CDA is a cost-effective alternative, however, in comparison to ACDF the results remain inconclusive. The lack of incorporation of disease specific measures into health state utility values, the inconsistent methods of calculating cost, and the fact that a vast majority of the results have come from industry-sponsored studies makes it difficult to form a definitive conclusion. Despite these limitations, both procedures have proven to be safe, effective, and cost-efficient alternatives.

Clinical Outcomes of Single-Level Anterior Cervical Discectomy and Fusion

Background

The purpose of the present study was to determine the differences in health outcomes between patients with cervical spondylosis who underwent single-level anterior cervical discectomy and fusion (ACDF) and patients with cervical spondylosis who did not undergo an ACDF fusion (non-ACDF). The hypothesis of the study was that patients undergoing single-level fusion have a lower risk of downstream cardiovascular disease and depression.

Methods

The Medicare 5% sample was used to identify patients who received a diagnosis of spondylosis during 2005-2012. All spondylosis patients were separated into nonoperative and operative groups. Differences in new disease diagnoses, age, sex, and Charlson Comorbidity Index (CCI) scores were recorded.

Results

The relative risk (RR) of heart failure was lower in the ACDF group after 3 years (RR = 0.6719; P < .05), 5 years (RR = 0.8477; P = 1.17), and 7 years (RR = 0.7709; P = 1.625). The RR of depression was higher in the ACDF group at 1 year (RR = 2.5008), 3 years (RR = 1.4473), 5 years (RR = 2.2625), and 7 years (RR = 2.2257; P < .05 for all). Mean CCI score of patients before undergoing ACDF was 10 (SD, 9.20), whereas the mean score after surgery was 8 (SD, 7.84; P < .05), and the score for non-ACDF patients remained unchanged at a CCI of 10 (SD, 9.00; P < .05).

Conclusions

The results demonstrate the patients in the ACDF cohort have an increased RR of depression but a decreased risk of cardiovascular disease. Further research may be needed to delineate why the ACDF procedure potentially benefits a patient for heart disease but may stress a patient's social/economic supports during the recovery process, thus leading to higher depression rates for patients undergoing ACDF.