Incidence of C5 Palsy and Recovery Rate After Cervical Spine Surgery: A Systematic Review and Meta-Analysis

Neurosurgery 98:520–542, 2026

This systematic review and meta-analysis quantifies C5 nerve palsy incidence and recovery following various cervical spine surgeries, comparing anterior and posterior approaches across 155 studies. Pooled rates show higher C5 palsy after posterior procedures (laminectomy 8%, PCDF 7.03%, laminoplasty 5.11%) versus anterior ACDF (2.61%), with overall low permanence rates.

The paper details methods, study selection, heterogeneity, and limitations, and emphasizes the need for standardized diagnostic criteria, prospective cohorts, and treatment algorithms. Findings aim to inform surgical decision-making, patient counseling, and future research priorities to mitigate C5 palsy risk.

C5 palsy incidence: Highest after laminectomy (8%), followed by posterior cervical decompression and fusion (PCDF, 7.03%), laminoplasty (5.11%), corpectomy (4.16%), and lowest after anterior cervical diskectomy and fusion (ACDF, 2.61%).

Permanent C5 palsy rates: Low across all procedures—laminectomy (1.44%), PCDF (1.02%), laminoplasty (0.28%), ACDF (1.06%); no pooled data for corpectomy.

Posterior approaches risk: Posterior decompression procedures (laminectomy, PCDF, laminoplasty) carry a higher risk of C5 palsy than anterior approaches (ACDF, corpectomy).

Resolution and recovery: Most C5 palsy cases are transient and resolve within months; permanent deficits are uncommon with proper follow-up and care.

Surgical decision-making: Choice of approach should consider C5 palsy risk, especially in patients with anatomic risk factors (e.g., narrow foramina, preexisting kyphosis).

Economic impact: C5 palsy increases healthcare costs significantly, with up to $347,000 in the first year and ongoing annual costs of about $42,000 for permanent deficits.

Standardized protocols lacking: There is no consensus on optimal management; most strategies are institution-specific and anecdotal, highlighting the need for standardized treatment protocols.

Research gaps: High study heterogeneity, inconsistent reporting, and lack of long-term data—especially for corpectomy—limit understanding; further prospective studies on risk factors and outcomes are needed.

Effect of workers’ compensation status on pain, disability, quality of life, and return to work after anterior cervical discectomy and fusion: a 1-year propensity score–matched analysis

J Neurosurg Spine 39:822–830, 2023

Patients with workers’ compensation (WC) claims are reported to demonstrate poorer surgical outcomes after lumbar spine surgery. However, outcomes after anterior cervical discectomy and fusion (ACDF) in WC patients remain debatable. The authors aimed to compare outcomes between a propensity score–matched population of WC and non-WC patients who underwent ACDF.

METHODS Patients who underwent 1- to 4-level ACDF were retrospectively reviewed from the prospectively maintained Quality Outcomes Database (QOD). After propensity score matching, 1-year patient satisfaction, physical disability (Neck Disability Index [NDI]), pain (visual analog scale [VAS]), EQ-5D, and return to work were compared between WC and non-WC cohorts.

RESULTS A total of 9957 patients were included (9610 non-WC and 347 WC patients). Patients in the WC cohort were significantly younger (50 ± 9.1 vs 56 ± 11.4 years, p < 0.001), less educated, and were more frequently male, non-Caucasian, and active smokers (29.1% vs 18.1%, p < 0.001), with greater baseline VAS and NDI scores and poorer quality of life (p < 0.001). One-year postoperative improvements in VAS, NDI, EQ-5D, and return-to-work rates and satisfaction were all significantly worse for WC compared with non-WC patients. After adjusting for baseline differences via propensity score matching, WC versus non-WC patients continued to demonstrate worse 3- and 12-month VAS neck pain and NDI (p = 0.010), satisfaction (χ 2 = 4.03, p = 0.045), and delayed return to work (9.3 vs 5.7 weeks, p < 0.001).

CONCLUSIONS WC status was associated with greater 1-year residual disability and axial pain along with delayed return to work, without any difference in quality of life despite having fewer comorbidities and being a younger population. Further studies are needed to determine the societal impact that WC claims have on healthcare delivery in the setting of ACDF.

Perioperative and swallowing outcomes in patients undergoing 4- and 5-level anterior cervical discectomy and fusion

J Neurosurg Spine 34:849–856, 2021

Anterior cervical discectomy and fusion (ACDF) is a common and robust procedure performed on the cervical spine. Literature on ACDF for 4 or more segments is sparse. Increasing the number of operative levels increases surgical complexity, tissue retraction, and risks of complications, particularly dysphagia. The overall risks of these complications and rates of dysphagia are not well studied for surgery on 4 or more segments. In this study, the authors evaluated their institution’s perioperative experience with 4- and 5-level ACDFs.

METHODS The authors retrospectively reviewed patients who underwent 4- or 5-level ACDF at their institution over a 6-year period (May 2013–May 2019). Patient demographics, perioperative complications, readmission rates, and swallowing outcomes were recorded. Outcomes were analyzed with a multivariate linear regression.

RESULTS A total of 174 patients were included (167 had 4-level and 7 had 5-level ACDFs). The average age was 60.6 years, and 54.0% of patients (n = 94) were men. A corpectomy was performed in 12.6% of patients (n = 22). After surgery, 56.9% of patients (n = 99) experienced dysphagia. The percentage of patients with dysphagia decreased to 22.8% (37/162) at 30 days, 12.9% (17/132) at 90 days, and 6.3% (5/79) and 2.8% (1/36) at 1 and 2 years, respectively. Dysphagia was more likely at 90 days postoperatively in patients with gastroesophageal reflux (OR 4.4 [95% CI 1.5–12.8], p = 0.008), and the mean (± SD) lordosis change was greater in patients with dysphagia than those without at 90 days (19.8° ± 13.3° vs 9.1° ± 10.2°, p = 0.003). Dysphagia occurrence did not differ with operative implants, including graft and interbody type. The mean length of time to solid food intake was 2.4 ± 2.1 days. Patients treated with dexamethasone were more likely to achieve solid food intake prior to discharge (OR 4.0 [95% CI 1.5–10.6], p = 0.004). Postsurgery, 5.2% of patients (n = 9) required a feeding tube due to severe approach-related dysphagia. Other perioperative complication rates were uniformly low. Overall, 8.6% of patients (n = 15) returned to the emergency department within 30 days and 2.9% (n = 5) required readmission, whereas 1.1% (n = 2) required unplanned return to surgery within 30 days.

CONCLUSIONS This is the largest series of patients undergoing 4- and 5-level ACDFs reported to date. This procedure was performed safely with minimal intraoperative complications. More than half of the patients experienced in-hospital dysphagia, which increased their overall length of stay, but dysphagia decreased over time.

A single-center retrospective analysis of 3- or 4-level anterior cervical discectomy and fusion

J Neurosurg Spine 34:45–51, 2021

Anterior cervical discectomy and fusion (ACDF) is a safe and effective intervention to treat cervical spine pathology. Although these were originally performed as single-level procedures, multilevel ACDF has been performed for patients with extensive degenerative disc disease. To date, there is a paucity of data regarding outcomes related to ACDFs of 3 or more levels. The purpose of this study was to compare surgical outcomes of 3- and 4-level ACDF procedures.

METHODS The authors performed a retrospective chart review of patients who underwent 3- and 4-level ACDF at the University of Virginia Health System between January 2010 and December 2017. In patients meeting the inclusion/exclusion criteria, demographics, fusion rates, time to fusion, and reoperation rates were evaluated. Fusion was determined by < 1 mm of change in interspinous distance between individual fused vertebrae on lateral flexion/extension radiographs and lack of radiolucency between the grafts and vertebral bodies. Any procedure requiring a surgical revision was considered a failure.

RESULTS Sixty-six patients (47 with 3-level and 19 with 4-level ACDFs) met the inclusion/exclusion criteria of having at least one lateral flexion/extension radiograph series ≥ 12 months after surgery. Seventy percent of 3-level patients and 68% of 4-level patients had ≥ 24 months of follow-up. Ninety-four percent of 3-level patients and 100% of 4-level patients achieved radiographic fusion for at least 1 surgical level. Eighty-eight percent and 82% of 3- and 4-level patients achieved fusion at C3–4; 85% and 89% of 3- and 4-level patients achieved fusion at C4–5; 68% and 89% of 3- and 4-level patients achieved fusion at C5–6; 44% and 42% of 3- and 4-level patients achieved fusion at C6–7; and no patients achieved fusion at C7–T1. Time to fusion was not significantly different between levels. Revision was required in 6.4% of patients with 3-level and in 16% of patients with 4-level ACDF. The mean time to revision was 46.2 and 45.4 months for 3- and 4-level ACDF, respectively. The most common reason for revision was worsening of initial symptoms.

CONCLUSIONS The authors’ experience with long-segment anterior cervical fusions shows their fusion rates exceeding most of the reported fusion rates for similar procedures in the literature, with rates similar to those reported for short-segment ACDFs. Three-level and 4-level ACDF procedures are viable options for cervical spine pathology, and the authors’ analysis demonstrates an equivalent rate of fusion and time to fusion between 3- and 4-level surgeries.

 

Asymptomatic ACDF Nonunions Underestimate the True Prevalence of Radiographic Pseudarthrosis

Spine 2020;45:E776–E780

Study Design. Secondary analysis of subjects in the control anterior cervical discectomy and fusion (ACDF) arm of Medtronic Investigational Device Exemption (IDE) trials for cervical disc arthroplasty (CDA).

Objectives. To compare patient-reported outcomes (PROs) in patients with radiographic nonunion to patients with a solid fusion. Summary of

Background Data. The true prevalence of nonunion after ACDF is unknown. Nonunion may be underreported, as some patients are not symptomatic enough to justify radiographic evaluation. Methods. Three hundred forty-five subjects enrolled in the control arm of IDE trials for CDA who had single-level ACDF with allograft and plate with 24 month data formed the study cohort. Using the 24-month postop evaluation, subjects were divided into those who had radiographic fusion and those who did not using strict study criteria. SF-36, NDI, Neck and Arm pain NRS scores were reported at 12, 24, 36, 60, and 84 months postop. For subjects who had secondary surgery failures, the last observations before the secondary surgery were carried forward to future visits for the analysis.

Results. Forty-four (13%) patients had radiographic nonunion and 301 (87%) were fused at 24 months postop. At 24 months, PROs were similar between the two groups. Seven patients in the Nonunion group (16%) and 10 (3%) in the Fused group had additional surgery at the index level prior to the 24 follow-up (P¼0.003). Over the 84-month follow-up a total of 9 patients in the Nonunion group (21%) and 22 (7%) in the Fused group had additional surgery at the index level (P¼0.009).

Conclusion. While the radiographic nonunion rate at 24 months was 13%, PROs show that many of the radiographic nonunions were asymptomatic. Although the majority of patients with radiographic nonunion did not undergo additional surgery, the rate of secondary surgeries at the index level was significantly higher in the radiographic nonunion group.

Level of Evidence: 2

Cost of Readmissions Following Anterior Cervical Discectomy and Fusion

Neurosurgery DOI:10.1093/neuros/nyz443

Postoperative readmissions are a significant driver of variation in bundled care costs associated with cervical spine surgery.

OBJECTIVE: To determine the factors predicting the cost of readmission episodes following elective anterior cervical discectomy and fusion (ACDF).

METHODS: We queried the Healthcare Cost and Utilization Project Nationwide Readmissions Database for patients undergoing elective ACDF during 2012 to 2015. Multivariable linear regression was performed to establish the factors associated with the cost of each 30-/90-d readmission episode.

RESULTS: A total of 139 877 and 113 418 patients met inclusion criteria for the evaluation of 30- and 90-d readmissions, respectively. Among these, the national rates of 30- and 90-d readmission after an elective ACDF were 3% and 6%, respectively. The median cost of a 30- and 90-d readmission episode was $6727 (IQR: $3844-$13 529) and $8507 (IQR: $4567- $17 460), respectively. Relative predictor importance analysis revealed that the number of procedures at index admission (IA), length of stay at IA, and time elapsed between index surgical admission and readmission were the top predictors of both 30- and 90-d readmission costs (all P < .001). Although cervical myelopathy accounted for only 3.6% of all 30-d readmissions, it accounted for the largest share (8%) of 30-d readmission costs.

CONCLUSION: In this analysis from a national all-payer database, we determined the factors associated with the cost of readmissions following elective ACDF. These results are important in assisting policymakers and payers with a better risk adjustment in bundled care payment systems and for surgeons in implementing readmission cost-reduction efforts.

Two-level cervical disc arthroplasty versus anterior cervical discectomy and fusion: 10-year outcomes of a prospective, randomized investigational device exemption clinical trial

J Neurosurg Spine 31:508–518, 2019

The authors assessed the 10-year clinical safety and effectiveness of cervical disc arthroplasty (CDA) to treat degenerative cervical spine disease at 2 adjacent levels compared to anterior cervical discectomy and fusion (ACDF).

METHODS A prospective, randomized, controlled, multicenter FDA-approved clinical trial was conducted comparing the low-profile titanium ceramic composite–based Prestige LP Cervical Disc (n = 209) at two levels with ACDF (n = 188). Ten-year follow-up data from a postapproval study were available on 148 CDA and 118 ACDF patients and are reported here. Clinical and radiographic evaluations were completed preoperatively, intraoperatively, and at regular postoperative follow-up intervals for up to 10 years. The primary endpoint was overall success, a composite variable that included key safety and efficacy considerations. Ten-year follow-up rates were 86.0% for CDA and 84.9% for ACDF.

RESULTS From 2 to 10 years, CDA demonstrated statistical superiority over ACDF for overall success, with rates at 10 years of 80.4% versus 62.2%, respectively (posterior probability of superiority [PPS] = 99.9%). Neck Disability Index (NDI) success was also superior, with rates at 10 years of 88.4% versus 76.5% (PPS = 99.5%), as was neurological success (92.6% vs 86.1%; PPS = 95.6%). Improvements from preoperative results in NDI and neck pain scores were consistently statistically superior for CDA compared to ACDF. All other study effectiveness measures were at least noninferior for CDA compared to ACDF through the 10-year follow-up period, including disc height. Mean angular ranges of motion at treated levels were maintained in the CDA group for up to 10 years. The rates of grade IV heterotopic ossification (HO) at the superior and inferior levels were 8.2% and 10.3%, respectively. The rate of severe HO (grade III or IV) did not increase significantly from 7 years (42.4%) to 10 years (39.0%). The CDA group had fewer serious (grade 3–4) implantrelated or implant/surgical procedure–related adverse events (3.8% vs 8.1%; posterior mean 95% Bayesian credible interval [BCI] of the log hazard ratio [LHR] -0.92 [-1.88, -0.01]). The CDA group also had statistically fewer secondary surgical procedures at the index levels (4.7%) than the ACDF group (17.6%) (LHR [95% BCI] -1.39 [-2.15, -0.61]) as well as at adjacent levels (9.0% vs 17.9%).

CONCLUSIONS The Prestige LP Cervical Disc, implanted at two adjacent levels, maintains improved clinical outcomes and segmental motion 10 years after surgery and is a safe and effective alternative to fusion.

Clinical trial registration no.: NCT00637156 (clinicaltrials.gov)

Fivefold higher rate of pseudarthrosis with polyetheretherketone interbody device than with structural allograft used for 1-level anterior cervical discectomy and fusion

J Neurosurg Spine 30:46–51, 2019

Common interbody graft options for anterior cervical discectomy and fusion (ACDF) include structural allograft and polyetheretherketone (PEEK). PEEK has gained popularity due to its radiolucency and its elastic modulus, which is similar to that of bone. The authors sought to compare the rates of pseudarthrosis, a lack of solid bone growth across the disc space, and the need for revision surgery with the use of grafts made of allogenic bone versus PEEK.

METHODS The authors retrospectively reviewed 127 cases in which patients had undergone a 1-level ACDF followed by at least 1 year of radiographic follow-up. Data on age, sex, body mass index, tobacco use, pseudarthrosis, and the reoperation rate for pseudarthrosis were collected. These data were analyzed by performing a Pearson’s chi-square test.

RESULTS Of 127 patients, 56 had received PEEK implants and 71 had received allografts. Forty-six of the PEEK implants (82%) were stand-alone devices. There were no significant differences between the 2 treatment groups with respect to patient age, sex, or body mass index. Twenty-nine (52%) of 56 patients with PEEK implants demonstrated radiographic evidence of pseudarthrosis, compared to 7 (10%) of 71 patients with structural allografts (p < 0.001, OR 9.82; 95% CI 3.836–25.139). Seven patients with PEEK implants required reoperation for pseudarthrosis, compared to 1 patient with an allograft (p = 0.01, OR 10.00; 95% CI 1.192–83.884). There was no significant difference in tobacco use between the PEEK and allograft groups (p = 0.586).

CONCLUSIONS The results of this study demonstrate that the use of PEEK devices in 1-level ACDF is associated with a significantly higher rate of radiographically demonstrated pseudarthrosis and need for revision surgery compared with the use of allografts. Surgeons should be aware of this when deciding on interbody graft options, and reimbursement policies should reflect these discrepancies.

Drivers of Variability in 90-Day Cost for Elective Anterior Cervical Discectomy and Fusion for Cervical Degenerative Disease

Neurosurgery 83:898–904, 2018

Value-based episode of care reimbursement models is being investigated to curb unsustainable health care costs. Any variation in the cost of index spine surgery can affect the payment bundling during the 90-d global period.

OBJECTIVE: To determine the drivers of variability in cost for patients undergoing elective anterior cervical discectomy and fusion (ACDF) for degenerative cervical spine disease.

METHODS: Four hundred forty-five patients undergoing elective ACDF for cervical spine degenerative diagnoses were included in the study. The direct 90-d cost was derived as sum of cost of surgery, cost associated with postdischarge utilization. Multiple variable linear regression models were built for total 90-d cost.

RESULTS: The mean 90-d direct cost was $17685 ± $5731. In a multiple variable linear regression model, the length of surgery, number of levels involved, length of hospital stay, preoperative history of anticoagulation medication, health-care resource utilization including number of imaging, any complications and readmission encounter were the significant contributor to the 90-d cost. The model performance as measured by R2 was 0.616.

CONCLUSION: There was considerable variation in total 90-d cost for elective ACDF surgery. Our model can explain about 62% of these variations in 90-d cost. The episode of care reimbursement models needs to take into account these variations and be inclusive of the factors that drive the variation in cost to develop a sustainable payment model. The generalized applicability should take in to account the differences in patient population, surgeons’ and institution-specific differences.

Esophageal perforation after anterior cervical spine surgery

esophageal-perforation-after-anterior-cervical-spine-surgery

J Neurosurg Spine 25:285–291, 2016

Esophageal perforation is a rare but well-known complication of anterior cervical spine surgery. The authors performed a systematic review of the literature to evaluate symptomatology, direct causes, repair methods, and associated complications of esophageal injury.

Methods A PubMed search that adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines included relevant clinical studies and case reports (articles written in the English language that included humans as subjects) that reported patients who underwent anterior spinal surgery and sustained some form of esophageal perforation. Available data on clinical presentation, the surgical procedure performed, outcome measures, and other individual variables were abstracted from 1980 through 2015.

Results The PubMed search yielded 65 articles with 153 patients (mean age 44.7 years; range 14–85 years) who underwent anterior spinal surgery and sustained esophageal perforation, either during surgery or in a delayed fashion. The most common indications for initial anterior cervical spine surgery in these cases were vertebral fracture/dislocation (n = 77), spondylotic myelopathy (n = 15), and nucleus pulposus herniation (n = 10). The most commonly involved spinal levels were C5–6 (n = 51) and C6–7 (n = 39). The most common presenting symptoms included dysphagia (n = 63), fever (n = 24), neck swelling (n = 23), and wound leakage (n = 18). The etiology of esophageal perforation included hardware failure (n = 31), hardware erosion (n = 23), and intraoperative injury (n = 14). The imaging modalities used to identify the esophageal perforations included modified contrast dye swallow studies, CT, endoscopy, plain radiography, and MRI. Esophageal repair was most commonly achieved using a modified muscle flap, as well as with primary closure. Outcomes measured in the literature were often defined by the time to oral intake following esophageal repair. Complications included pneumonia (n = 6), mediastinitis (n = 4), osteomyelitis (n = 3), sepsis (n = 3), acute respiratory distress syndrome (n = 2), and recurrent laryngeal nerve damage (n = 1). The mortality rate of esophageal perforation in the analysis was 3.92% (6 of 153 reported patients).

Conclusions Esophageal perforation after anterior cervical spine surgery is a rare complication. This systematic review demonstrates that these perforations can be stratified into 3 categories based on the timing of symptomatic onset: intraoperative, early postoperative (within 30 days of anterior spinal surgery), and delayed. The most common source of esophageal injury is hardware erosion or migration, each of which may vary in their time to symptomatic manifestation.

Long-term Outcomes of the US FDA IDE Prospective, Randomized Controlled Clinical Trial Comparing PCM Cervical Disc Arthroplasty With Anterior Cervical Discectomy and Fusion”

PCM vs ACDF

Spine 2015;40:674–683

Study Design. Prospective, multicenter, randomized clinical trial.

Objective. To evaluate the long-term safety and effectiveness of the PCM Cervical Disc compared with anterior cervical discectomy and fusion (ACDF) in treatment of patients with symptomatic single- level degenerative spondylosis between C3–C4 and C7–T1 with or without prior cervical fusion.

Summary of Background Data. The 2-year results of the PCM Cervical Disc trial have been reported previously. The current study reports the long-term results of the same trial.

Methods. Patients with single-level cervical spondylosis and radiculopathy with or without myelopathy unresponsive to nonoperative treatment were enrolled. The per protocol patient sample at 5 years included 293 patients (163 PCM, 130 ACDF). Adverse events and secondary surgical procedures are reported on the cohorts through current follow-up, which include 110 patients (68 PCM, 42 ACDF) at 7 years.

Results. At 5 years postoperative, all patient-reported outcomes— neck and arm pain visual analogue scale score, neck disability index, and general health (36-Item Short Form Health Survey physical and mental component scores: physical component summary, mental component summary)—were significantly improved from baselines in both groups, and mean scores were significantly better in the PCM group for neck disability index (P = 0.001), neck pain (P = 0.002), general health (Pphysical component summary= 0.014; P mental component summary= 0.004), and patient satisfaction (P = 0.005).
PCM patients trended toward fewer 2- to 7-year device-related
serious adverse events (1/214, 0.5% PCM; 2/190, 1.1% ACDF) and secondary surgical procedures (7/211, 3.3% PCM; 14/290, 7.6% ACDF). Adjacent-level degeneration was radiographically more frequent after ACDF (33.1% PCM, 50.9% ACDF; P = 0.006) and was the primary indication for the increase in late-term secondary surgical procedures after ACDF.

Conclusion. The long-term results show good clinical outcomes after ACDF and PCM arthroplasty. PCM patients showed greater improvement in neck disability index and neck pain scores with a lower rate of radiographical adjacent-level degeneration and a trend toward fewer secondary surgical procedures. These data support PCM arthroplasty to be a viable and sustainable alternative to ACDF.
Level of Evidence: 1

Clinical Outcomes of Bryan Cervical Disc Arthroplasty A Prospective, Randomized, Controlled, Single Site Trial With 48-Month Follow-up

J Spinal Disord Tech 2010;23:367–371

Study Design: Prospective, randomized, controlled. Level 1 evidence.

Objective: To report functional outcomes at 48 months followup on prospectively randomized patients to either the Bryan cervical disc prosthesis or anterior cervical discectomy and fusion (ACDF) at a single site.

Summary of Background Data: Surgical treatment of cervical disc pathology can involve discectomy and fusion (ACDF), the gold standard technique. The safety and effectiveness of this procedure has been established and demonstrated in the literature, however, limitations have evolved and alternatives such as disc replacement are being investigated. Intervertebral disc replacement is designed to preserve motion, both at affected and adjacent levels avoiding limitations of fusion such as adjacent level degeneration. New onset degenerative changes and possible recurring neurologic symptoms may be deferred or eliminated with cervical disc replacement. A recent multicenter trial with 24 months follow-up has shown the Bryan disc to compare favorably with ACDF. Continued follow-up is needed to further evaluate and compare functional outcomes in both these cohorts.

Methods: A total of 47 patients were enrolled at our site as part of an ongoing multicenter prospectively randomized study investigating ACDF versus Bryan cervical disc prosthesis. Functional outcomes are now reported at 48 months follow-up for our cohort of participants. Neck disability index score (NDI), VAS neck and arm and SF-36 both physical and mental as well as complications and reoperations will be reported.

Results: Functional outcome data collected at routine follow-up for 48-months has favorably demonstrated improved functional outcomes for NDI, neck/arm pain VAS scores, and the SF-36 physical/mental health component scores for the Bryan arthroplasty and ACDF cohorts. The NDI scores for the Bryan arthroplasty preoperatively was 51 and at 48 months 10. For ACDF preoperative NDI score was also 51 and at 48 months 16.7. At 48 months NDI success, measured by Z15 points NDI improvement demonstrated a 93.3% success for Bryan arthroplasty and an 82.4%success for ACDF. VAS neck pain scores for the Bryan arthroplasty preoperatively was 76.2 and at 48 months was 13.6. VAS neck pain scores for ACDF preoperatively was 80.6 and at 48 months was 28.1. Arm Pain scores were also measured and for the Bryan arthroplasty preoperatively measured 78.8 and at 48 months 10.8. For ACDF arm pain scores preoperatively measured 77.1 and at 48 months 21.7. These outcomes have not been associated with any degradation of outcome measures from 2 to 4 years. During the 48 months of follow-up at our institution we also report 6 secondary surgeries in our control group (ACDF) and only 1 in our investigational group (Bryan). Of the 6 surgeries in the control group performed, 3 or 12% to date were for adjacent level degenerative disease and 1 or 4% for remote level degenerative disc disease. The remaining 2 surgeries were performed on the same patient for a pseudarthrosis. In the investigational group there was only 1 secondary surgery performed to date for adjacent level disease 5%.

Conclusions: At 48 months, cervical arthroplasty with the Bryan cervical disc prosthesis continues to compare favorably to ACDF at our institution. There has been no degradation of functional outcomes from 24 to 48 months for NDI, VAS of neck and arm, and SF-36. There has been a lower incidence of secondary surgeries for the Bryan arthroplasty cohort to date.