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Christopher D. Witiw, Fabrice Smieliauskas, Sandra A. Ham and Vincent C. Traynelis


Cervical disc replacement (CDR) has emerged as an alternative to anterior cervical discectomy and fusion (ACDF) for the management of cervical spondylotic pathology. While much is known about the efficacy of CDR within the constraints of a well-controlled, experimental setting, little is known about general utilization. The authors present an analysis of temporal and geographic trends in “real-world” utilization of CDR among those enrolled in private insurance plans in the US.


Eligible subjects were identified from the IBM MarketScan Databases between 2009 and 2017. Individuals 18 years and older, undergoing a single-level CDR or ACDF for cervical radiculopathy and/or myelopathy, were identified. US Census divisions were used to classify the region where surgery was performed. Two-level mixed-effects regression modeling was used to study regional differences in proportional utilization of CDR, while controlling for confounding by regional case-mix differences.


A total of 47,387 subjects met the inclusion criteria; 3553 underwent CDR and 43,834 underwent ACDF. At a national level, the utilization of single-level CDR rose from 5.6 cases for every 100 ACDFs performed in 2009 to 28.8 cases per 100 ACDFs in 2017. The most substantial increases occurred from 2013 onward. The region of highest utilization was the Mountain region (Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming), where 14.3 CDRs were performed for every 100 ACDFs (averaged over the 9-year period of study). This is in contrast to the East South Central region (Alabama, Kentucky, Mississippi, and Tennessee), where only 2.1 CDRs were performed for every 100 ACDFs. Patient factors that significantly increased the odds of undergoing a CDR were age younger than 40 years (OR 15.9 [95% CI 10.0–25.5]; p < 0.001), no clinical evidence of myelopathy/myeloradiculopathy (OR 1.5 [95% CI 1.4–1.7]; p < 0.001), and a Charlson Comorbidity Index score of 0 (OR 2.7 [95% CI 1.7–4.2]; p < 0.001). After controlling for these factors, significant differences in utilization rates remained between regions (chi-square test = 830.4; p < 0.001).


This US national level study lends insight into the rate of uptake and geographic differences in utilization of the single-level CDR procedure. Further study will be needed to ascertain specific factors that predict adoption of this technology to explain observed geographic discrepancies.

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Sandi Lam, Dominic Harris, Brandon G. Rocque and Sandra A. Ham


Endoscopic third ventriculostomy (ETV) is an alternative to ventriculoperitoneal shunting for hydrocephalus treatment. Choice of treatment options raises questions about which patients are likely to benefit from ETV. The authors performed a population-based analysis using an administrative claims database, examining current practice and outcomes for pediatric patients in the US.


The authors queried the MarketScan (Truven Health Analytics) database for Current Procedural Terminology codes corresponding to ETV and ventriculoperitoneal shunting from 2003 to 2011; they included patients 19 years or younger and extracted data from initial and subsequent hospitalizations. Hydrocephalus etiology was classified with ICD-9-CM coding. ETV failure was defined as any subsequent ETV or shunt procedure.


Five hundred one patients underwent ETV. Of these, 46% were female. The mean age was 8.7 ± 6.4 years (± SD). The mean follow-up was 1.9 ± 1.8 years. Etiology of hydrocephalus was primarily tumor (41.7%) and congenital/aqueductal stenosis (24.4%). ETV was successful in 354 patients (71%). The mean time to failure was 109.9 ± 233 days. Of the 147 patients with ETV failure, 35 (24%) underwent repeat ETV and 112 (76%) had shunt placement. Patients in age groups 0 to < 6 months and 6 months to < 1 year had a significantly higher rate of ETV failure than those 10–19 years (HR 2.9, p = 0.05; and HR 2.3, p = 0.001, respectively). History of prior shunt was associated with higher risk of failure (HR 2.5, p < 0.001). There were no significant associations between hydrocephalus etiology and risk of failure. A second wave of failures occurred at 2.5–3.5 years postoperative in tumor and congenital/aqueductal stenosis patients; this was not observed in other etiology groups.


This study represents a cross-section of nationwide ETV practice over 9 years. ETV success was more likely among children 1 year and older and those with no history of prior shunt.