The Safety of Single and Multilevel Cervical Total Disc Replacement in Ambulatory Surgery Centers

Safety and Efficacy of Outpatient Anterior Cervical Disk Replacement (ACDR) in an Ambulatory Surgery Center Versus Hospital Setting: A 2-year Retrospective Analysis

STUDY DESIGN

Retrospective cohort analysis.

OBJECTIVE

To compare clinical outcomes of outpatient anterior cervical disk replacements (ACDR) performed in free-standing private ambulatory surgery centers versus tertiary hospital centers.

SUMMARY OF BACKGROUND DATA

ACDR is an increasingly popular technique for treating various degenerative pathologies of the cervical spine. There has been an increase in the utilization of ambulatory surgery centers (ASCs) for outpatient cervical procedures due to economic and convenience benefits; however, a paucity of literature exists in evaluating long-term safety and efficacy of ACDRs performed in ASCs versus outpatient hospital centers.

METHODS

A retrospective cohort review of all patients undergoing 1- or 2-level ACDRs at 2 outpatient ASCs and 4 tertiary care medical centers from 2012 to 2020, with a minimum follow-up of 24 months, was performed. Approval by each patient's insurance and patient preference determined distribution into an ASC or non-ASC. Demographics, perioperative data, length of follow-up, complications, and revision rates were analyzed. Functional outcomes were assessed using VAS and NDI at follow-up visits.

RESULTS

One hundred seventeen patients were included (65 non-ASC and 52 ASC). There were no significant differences in demographics or length of follow-up between the cohorts. ASC patients had significantly lower operative times (ASC: 89.5 minutes vs. non-ASC: 110.5 minutes, P<0.001) and mean blood loss (ASC: 17.5 mL vs. non-ASC: 25.3 mL, P<0.001). No significant differences were observed in rates of dysphagia (ASC: 21.2% vs. non-ASC: 15.6%, P<0.001), infection (ASC: 0.0% vs. non-ASC: 1.6%, P=0.202), ASD (ASC: 1.9% vs. non-ASC: 1.6%, P=0.202), or revision (ASC: 1.9% vs. non-ASC: 0.0%, P=0.262). Both groups demonstrated significant improvements in VAS and NDI scores (P<0.001), but no significant differences in the degree of improvement were observed.

CONCLUSIONS

Our 2-year results demonstrate that ACDRs performed in ASCs may offer the advantages of reduced operative time and blood loss without an increased risk of postoperative complications.

The Safety and Efficacy of Posterior Lumbar Interbody Fusions in the Outpatient Setting

Introduction Outpatient surgical procedures have shown reduced costs, improved patient outcomes, and decreased postoperative complications. Interest in moving orthopedic and neurosurgical spine procedures to the outpatient setting has grown in recent years because of these factors. Studies investigating open posterior lumbar interbody fusions (PLIFs) in the outpatient setting are sparse. Methods The patients who underwent an open PLIF with pedicle screw and rod construct from 2014 to 2018 were retrospectively reviewed. Outpatient procedures were defined by patient discharge being on the same day of the procedure, without admittance to an inpatient ward. Pertinent demographic, clinical, radiographic, and surgical data were collected and analyzed. Results The current study included 36 outpatient PLIF cases with 94.4% of the study cohort undergoing a single-level PLIF. The average Oswestry Disability Index (ODI) score improved by 20.4 points from preoperative measurements (p = 0.0002), and the visual analog scale (VAS) score improved by 27.2 points (p = 0.0001). The postoperative fusion rate was 94.4%. One intraoperative complication occurred (2.78%), and four postoperative complications occurred (11.11%). There were no subsequent admissions throughout the postoperative follow-up period; however, two of the 36 patients (5.56%) did require reoperation, both in an outpatient setting. Conclusions This study demonstrates that open posterior lumbar interbody fusions performed in an outpatient setting can be performed safely and effectively, with a significant reduction in VAS and ODI pain scores.

An Atypical Presentation of Early Periprosthetic Infection After Cervical Disc Arthroplasty: A Case Report

CASE

A 22-year-old woman with Klippel-Feil syndrome who underwent cervical disc arthroplasty (CDA) presented 3 months postoperatively with worsening neck pain and radiculopathy. Work-up was negative for infection, but single-photon emission computed tomography revealed increased metabolic activity in the vertebral body below the implant. During revision, the implant was grossly loose and multiple cultures grew Cutibacterium acnes. She was treated with an antibiotic course and conversion to anterior fusion without recurrence.

CONCLUSION

This report highlights the rare presentation of an early periprosthetic infection after CDA caused by C. acnes.

No Significant Differences in Postoperative Complications Between Outpatient and Inpatient Single-level or Multiple-level Cervical Disk Replacement for Cervical Radiculopathy

STUDY DESIGN

Retrospective cohort analysis.

OBJECTIVE

To investigate the safety profile of outpatient versus inpatient single-level and multiple-level cervical disk replacement (CDR) by analyzing one- and two-year surgical outcomes and 90-day medical complications using a large patient database.

SUMMARY OF BACKGROUND DATA

CDR is becoming a more desirable option for patients undergoing cervical spine procedures. Unlike anterior cervical diskectomy and fusion, CDR is motion-preserving and has been shown to reduce rates of adjacent segment disease. Current literature investigating outpatient versus inpatient CDR has shown a similar safety profile among the two cohorts. However, most of these studies have relatively small sample sizes with short-term follow-up.

MATERIALS AND METHODS

A retrospective cohort study was done using the PearlDiver patient database between 2010 and 2019. Patients who underwent single-level and multiple-level CDR with a follow-up of at least two years were identified. Patients within each procedure cohort were subdivided into an outpatient and an inpatient group. Univariate and multivariable analyses were performed.

RESULTS

In total, 2294 patients underwent single-level CDR of which 506 patients underwent outpatient CDR and 1788 underwent inpatient CDR. In total, 236 patients underwent multiple-level CDR of which 49 patients underwent outpatient CDR and 187 underwent inpatient CDR. In the single-level CDR cohort, patients undergoing outpatient CDR were found to have lesser odds of a decompressive laminectomy at one year following the initial procedure (odds ratio=0.471; 95% confidence interval: 0.205-0.945; P =0.05). No significant differences in one- and two-year surgical complications, or 90-day postoperative complications, were found on multivariate analysis of outpatient versus inpatient multiple-level CDR.

CONCLUSION

Our study found that performing single-level and multiple-level CDR on an outpatient basis has a similar safety profile to patients who underwent these procedures in an inpatient setting.

LEVEL OF EVIDENCE

3.

Comparison of the Safety of Outpatient Cervical Disc Replacement With Inpatient Cervical Disc Replacement: A Systematic Review and Meta-Analysis

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVES

Outpatient cervical disc replacement (CDR) has been performed with an increasing trend in recent years. However, the safety profile surrounding outpatient CDR remains insufficient. The present study systematically reviewed the current studies about outpatient CDR and performed a meta-analysis to evaluate the current evidence on the safety of outpatient CDR as a comparison with the inpatient CDR.

METHODS

We searched the PubMed, Embase, Web of Science, and Cochrane Library databases comprehensively up to April 2020. Patient demographic data, overall complication, readmission, returning to the operation room, operating time were analyzed with the Stata 14 software and R 3.4.4 software.

RESULTS

Nine retrospective studies were included. Patients underwent outpatient CDR were significantly younger (mean difference [MD] = -1.97; 95% CI -3.80 to -0.15; P = .034) and had lower prevalence of hypertension (OR = 0.68; 95% CI 0.53-0.87; P = .002) compared with inpatient CDR. The pooled prevalence of overall complication was 0.51% (95% CI 0.10% to 1.13%) for outpatient CDR. Outpatient CDR had a 59% reduction in risk of developing complications (OR = 0.41; 95% CI 0.18-0.95; P = .037). Outpatient CDR showed significantly shorter operating time (MD = -18.37; 95% CI -25.96 to -10.77; P < .001). The readmission and reoperation rate were similar between the 2 groups.

CONCLUSIONS

There is a lack of prospective studies on the safety of outpatient CDR. However, current evidence shows outpatient CDR can be safely performed under careful patient selection. High-quality, large prospective studies are needed to demonstrate the generalizability of this study.

Comparison of the safety of outpatient cervical disc replacement with inpatient cervical disc replacement: A protocol for a meta-analysis

BACKGROUND

Cervical disc replacement (CDR) has been widely used as an effective treatment for cervical degenerative disc diseases in recent years. However, the cost of this procedure is very high and may bring a great economic burden to patients and the health care system. It is reported that outpatient procedures can reduce nearly 30% of the costs associated with hospitalization compared with inpatient procedures. However, the safety profile surrounding outpatient CDR remains poorly resolved. This study aims to evaluate the current evidence on the safety of outpatient CDR METHODS:: Four English databases were searched. The inclusion and exclusion criteria were developed according to the PICOS principle. The titles and abstracts of the records will be screened by 2 authors independently. Records that meet the eligibility criteria will be screened for a second time by reading the full text. An extraction form will be established for data extraction. Risk of bias assessment will be performed by 2 authors independently using Cochrane risk of bias tool or Newcastle-Ottawa scale. Data synthesis will be conducted using Stata software. Heterogeneity among studies will be assessed using I test. The funnel plot, Egger regression test, and Begg rank correlation test will be used to examine the publication bias.

RESULTS

The results of this meta-analysis will be published in a peer-review journal.

CONCLUSION

This will be the first meta-analysis that compares the safety of outpatient CDR with inpatient CDR. Our study will help surgeons fully understand the complications and safety profile surrounding outpatient CDR. OSF REGISTRATION NUMBER:: doi.org/10.17605/OSF.IO/3597Z.

Influence of cement-augmented pedicle screws with different volumes of polymethylmethacrylate in osteoporotic lumbar vertebrae over the adjacent segments: a 3D finite element analysis

Background

Polymethylmethacrylate (PMMA) is commonly used for cement-augmented pedicle screw instrumentation (CAPSI) to improve the fixation stability and reduce the risk of screw loosening in the osteoporotic thoracolumbar spine. Biomechanical researches have shown that various dose of cement (1-3 ml) can be injected to enhance screw stability. To date, there have been no studies on the relationship between adjacent segment degeneration and the volume of PMMA. This study aimed to explore the influence of CAPSI with different volumes of PMMA in osteoporotic lumbar vertebrae over adjacent segments by using finite element analysis.

Methods

Seven different finite element models were reconstructed and simulated under different loading conditions, including (1) an intact model, (2) three single-level CAPSI models with different volumes of PMMA (1, 1.73, and 2.5 ml), and (3) three double-level CAPSI models with different volumes of PMMA (1, 1.73, and 2.5 ml). To improve the accuracy of the finite element analysis, the models of the injectable pedicle screw and bone cement were created by using a three-dimensional scanning machine and the CAPSI patient’s CT data, respectively. The range of motion (ROM), the stress of intervertebral discs, and the stress of facet in the adjacent segment were comparatively analyzed among the different models.

Results

The ROMs of the different segments were compared with experimental data, with good agreement under the different load conditions (21.3°, 13.55°, 13.99°, and 6.11° in flexion, extension, bending, and rotation at L3-S1 level, respectively). Compared with the intact model, the ROM, disc stresses, and facet stress in adjacent segments were found to be higher in the six operative models. Otherwise, with a larger volume of PMMA injected, the ROM, disc stresses, and facet stress slightly increased at the adjacent segment. However, the differences were insignificant with the biggest difference less than 3.8%.

Conclusions

CAPSI could increase the incidence of disk degeneration in the adjacent segment, while within a certain range, different volumes of PMMA provided an approximate impact over the adjacent segment degeneration.