Abstract
Study Design
Retrospective cohort study.
Objectives
This study aimed to examine national trends in utilization, charges, and patient characteristics associated with endoscopic spine surgery (ESS) in ambulatory surgery centers (ASCs) from 2018 to 2022.
Methods
The Nationwide Ambulatory Surgery Sample (NASS) was queried for adult encounters identified by Current Procedural Terminology code 62380. Cases with valid weights and complete charge, payer, region (defined as HCUP U.S. Census regions), and month data were retained. Facility charges were inflation-adjusted to 2022 USD and winsorized at the 1st and 99th percentiles. Survey-weighted models estimated differences in charges and temporal trends, with pairwise comparisons from estimated marginal means. Significance was set at the P < 0.05 level.
Results
A total of 3097 ESS procedures were analyzed. Most were performed in urban settings (93.5%) and among patients in the highest income quartile (34.6%). Private insurance was the most common payer (47.8%), though self-pay utilization rose from 0.8% in 2018 to 9.7% in 2022 (P < 0.001). Costs varied significantly by payer and region, with self-pay patients incurring the highest charges ($70,000; P < 0.001) and the West recording the highest regional costs ($68,700; P < 0.001). Procedure volume increased in the West — from 4.3% of national volume in 2018 to 31.0% in 2022 (P < 0.001).
Conclusions
ESS in ASCs exhibited rapid procedural growth, particularly in the Western U.S., alongside substantial payer and region-specific variation in cost. These findings highlight the need for continued evaluation of access and reimbursement equity as ESS expands nationally.
Keywords: endoscopic spine surgery, ambulatory surgical centers, cost analysis, payer trends, utilization, nationwide ambulatory surgery sample
Introduction
Degenerative lumbar spine disease (DSD) is a leading cause of disability and healthcare utilization worldwide, affecting an estimated 266 million individuals annually. 1 In the United States (U.S.), nonspecific low back pain frequently precedes a diagnosis of specific lumbar pathology such as disc herniation, radiculopathy, or spinal stenosis, with over 8% of patients receiving a specific diagnosis within a year of initial presentation. 2 As conservative treatments fail in a subset of these patients, surgical decompression may be indicated to alleviate neural compression and restore function. In particular, endoscopic spine surgery (ESS) has gained increasing attention as a minimally invasive alternative to open procedures for treating lumbar disc pathology and spinal stenosis.3,4
ESS offers several demonstrated advantages over open and tubular decompression approaches, including smaller incisions, reduced soft tissue disruption, shorter hospital stays, and faster return to work.5-7 Advances in biportal and uniportal platforms have enhanced visualization and maneuverability, enabling surgeons to confidently manage complex pathologies such as foraminal or multilevel stenosis.8,9 Systematic reviews and registry studies have reported favorable complication profiles and outcomes, particularly in the lumbar spine.10,11 However, careful patient selection remains essential, as ESS may be contraindicated in cases of spinal instability, deformity requiring fusion, or heavily calcified/central stenosis.12,13 Despite increasing evidence supporting its safety and effectiveness, ESS adoption in the U.S. has remained limited and regionally variable.14,15 Most prior analyses have focused on inpatient or Medicare data, with less attention to its use in ambulatory surgery centers (ASCs) — settings increasingly preferred for spine procedures due to efficiency and recovery benefits.16,17 While societal cost-effectiveness is promising, concerns persist regarding direct procedural expenses and reimbursement variability.18,19 Understanding how ESS utilization and charges vary by payer and region has direct clinical and policy relevance. It informs coverage determinations, prior-authorization and site-of-service decisions, and resource allocation for training and equipment, all of which shape access and equity in outpatient spine care.
The present study leverages a nationally representative ambulatory surgery database to characterize recent trends in endoscopic lumbar decompression procedures performed in hospital-owned ASCs between 2018 and 2022. This study aims to: (1) evaluate temporal trends in procedure volume and facility-adjusted costs; (2) compare utilization and cost patterns across payer types, geographic regions, and seasons; and (3) identify patient, hospital, and procedural factors associated with increased costs and regional growth. By clarifying these patterns, our findings have implications for coverage policy, site-of-service authorization, and equitable access to endoscopic lumbar decompression in ambulatory settings. We hypothesized that overall utilization and inflation-adjusted charges for endoscopic spine surgery would increase over the study period, particularly among privately insured patients and in higher-income, urban regions.
Methods
Data Source
We conducted a retrospective cross-sectional analysis using the Nationwide Ambulatory Surgery Sample (NASS), developed by the Healthcare Cost and Utilization Project (HCUP), to evaluate endoscopic lumbar decompression procedures performed between 2018 and 2022. 20 NASS is a nationally representative database that captures discharge-level data from hospital-owned ASCs across the U.S. To generate national estimates, all analyses incorporated HCUP-provided discharge-level weights, consistent with established HCUP methodology. As the data are de-identified and publicly available, this study was exempt from Institutional Review Board (IRB) approval, and individual informed consent was not required.
Procedure Identification
Procedures were identified using Current Procedural Terminology (CPT) code 62380, which denotes single-level endoscopic lumbar decompression. Each record in NASS corresponds to an individual surgical encounter, and only cases coded with CPT 62380 were retained for analysis.
Inclusion and Exclusion Criteria
Records were included if they had non-missing discharge weights, positive adjusted total charges, and complete data for key variables including payer type, geographic region, and procedure month. To minimize the influence of extreme outliers, adjusted total charges were winsorized at the 1st and 99th percentiles. All cost values were inflation-adjusted to 2022 U.S. dollars using the Medical Consumer Price Index. 21 In the NASS database, the monetary field represents facility-reported total charges per encounter. These figures reflect billed amounts, are not actual economic costs or payer reimbursements, and exclude professional (surgeon/anesthesia) fees. We therefore report this variable as charges.
Variables and Outcomes of Interest
Patient-level variables extracted from NASS included age, sex, race/ethnicity, and estimated median household income quartile based on ZIP code of residence. Income quartiles follow HCUP’s income quartile classification, which is derived from Claritas ZIP-code median household income and updated annually to reflect year-specific thresholds (Appendix 1). Hospital-level characteristics included region (Northeast, Midwest, South, West), defined per U.S. Census Bureau regions as implemented by HCUP, and location type (urban or rural). The season of surgery was determined from the procedure month and categorized as Winter (December to February), Spring (March to May), Summer (June to August), or Fall (September to November). All estimates are survey-weighted to provide national inferences for hospital-owned ASCs across contributing states.
NASS samples hospital-owned ASCs from participating states and provides discharge weights to generate nationally representative estimates. State-level identifiers are not reported in the dataset. Primary outcomes included adjusted total charges per encounter and national procedure volume for endoscopic lumbar decompression. Secondary outcomes included subgroup differences in charges and volume by payer, region, and season, temporal trends in charges and volume from 2018 to 2022, and descriptive distributions of patient and hospital characteristics and primary diagnosis indications within the cohort.
Statistical Analysis
All analyses incorporated HCUP discharge-level weights and survey design features. Descriptive comparisons used Rao-Scott chi-square tests for categorical variables and design-based Wald tests for continuous variables. For charge outcomes, we fit survey-weighted generalized linear models with log-transformed adjusted total charges as the dependent variable and payer, region, or season as the main effect in separate models, and we reported back-transformed estimated marginal means as geometric means. Pairwise differences were evaluated with Wald tests, and a familywise Bonferroni correction was applied across each set of pairwise comparisons. Temporal trends in charges were assessed by adding year as a continuous term and testing interactions with payer, region, and season. For volume outcomes, we computed annual survey-weighted procedure counts overall and by subgroup. Between-group differences used survey-weighted pairwise contrasts with Bonferroni correction, and temporal trends were evaluated using inverse-variance weighted linear regression of annual estimates against year. All data management, statistical modeling, and figure generation were conducted in R version 4.3.1 (R Foundation for Statistical Computing, Vienna, Austria). Statistical significance was set at the P < 0.05 level.
Results
Patient, Payer, and Regional Characteristics
A total of 3097 endoscopic lumbar decompression procedures were analyzed between 2018 and 2022, with annual weighted sample sizes ranging from 419 in 2018 to 800 in 2021. The cohort was approximately balanced by sex (54.5% male) with a median age of 56 years (IQR: 42-67), which was consistent across years (P = 0.300). Most procedures (93.5%) were performed in urban settings, although rural utilization increased from 5.3% in 2018 to 9.0% in 2022 (P = 0.011). In terms of socioeconomic status, patients in the highest income quartile comprised the largest share (34.6%), with an upward trend from 34.0% in 2018 to 38.0% in 2022 (P = 0.018).
Private insurance was the most common payer (45.8%), followed by Medicare (31.2%), other insurance (10.2%), Medicaid (7.0%), and self-pay (5.8%) over the entire study period. Regionally, the South accounted for the largest volume, but the West exhibited the steepest growth, increasing from 4.3% of procedures in 2018 to 31.0% in 2022 (P < 0.001; Table 1; Figure 1). Furthermore, across the study years, the South showed a repeating rise and fall in annual volume, whereas the West demonstrated a transient dip around 2020 and a later decline in 2022.
Table 1.
Patient Characteristics by Year
| Patient characteristic | 2018 | 2019 | 2020 | 2021 | 2022 | P value* |
|---|---|---|---|---|---|---|
| N = 419 (%) | N = 592 (%) | N = 589 (%) | N = 800 (%) | N = 697 (%) | ||
| Sex | 0.120 | |||||
| Female | 197 (47.0%) | 284 (48.0%) | 233 (40.0%) | 355 (44.4%) | 315 (45.2%) | |
| Male | 222 (53.0%) | 308 (52.0%) | 356 (60.0%) | 445 (55.6%) | 382 (54.8%) | |
| Age | 55 | 56 | 56 | 56 | 57 | 0.300 |
| Location | 0.011 | |||||
| Rural | 22 (5.3%) | 23 (3.9%) | 38 (6.4%) | 63 (7.9%) | 63 (9.0%) | |
| Urban | 397 (94.7%) | 569 (96.1%) | 551 (93.6%) | 737 (92.1%) | 634 (91.0%) | |
| Income c | 0.018 | |||||
| 1st quartile | 80 (19.0%) | 101 (17.0%) | 88 (15.0%) | 128 (16.0%) | 105 (15.0%) | |
| 2nd quartile | 96 (23.0%) | 130 (22.0%) | 124 (21.0%) | 200 (25.0%) | 160 (23.0%) | |
| 3rd quartile | 101 (24.0%) | 183 (31.0%) | 183 (31.0%) | 168 (21.0%) | 167 (24.0%) | |
| 4th quartile | 142 (34.0%) | 178 (30.0%) | 194 (33.0%) | 304 (38.0%) | 265 (38.0%) | |
| Payer | <0.001 | |||||
| Medicaid | 31 (7.4%) | 30 (5.0%) | 39 (6.7%) | 54 (6.8%) | 62 (8.9%) | |
| Medicare | 136 (32.5%) | 166 (28%) | 183 (31%) | 255 (31.9%) | 227 (32.6%) | |
| Other | 51 (12.2%) | 57 (9.6%) | 57 (9.6%) | 66 (8.3%) | 84 (12.1%) | |
| Private insurance | 198 (47.3%) | 308 (52%) | 283 (48%) | 375 (46.9%) | 256 (36.7%) | |
| Self-pay | N ≤10 a | 32 (5.4%) | 27 (4.7%) | 50 (6.3%) | 68 (9.7%) | |
| Region | <0.001 | |||||
| Midwest | 105 (25%) | 98 (16.6%) | 123 (20.9%) | 121 (15.1%) | 98 (14.0%) | |
| Northeast | 142 (33.9%) | 126 (21.3%) | 110 (18.7%) | 161 (20.1%) | 203 (29.0%) | |
| South | 154 (36.8%) | 232 (39.2%) | 178 (30.2%) | 241 (30.1%) | 182 (26.0%) | |
| West | 18 (4.3%) | 136 (22.9%) | 178 (30.2%) | 277 (34.6%) | 214 (31.0%) | |
| Cost ($) b | 30,603 | 34,866 | 39,661 | 42,287 | 38,426 | <0.001 |
$ = United States dollars; % = percentage. Significance was set at the P < 0.05 level.
aSignifies that the count number is < 10 and cannot be reported.
bMedian costs were utilized.
cIncome quartiles are defined by the Healthcare Cost & Utilization Project and vary by year; see Appendix 1 for 2018 through 2022 thresholds. *P values: Calculated using Pearson’s χ2 test with Rao & Scott second-order correction for categorical variables and design-based Kruskal–Wallis test for continuous variables.
Figure 1.
Trends in Estimated Procedure Volume for Endoscopic Spine Surgeries Performed in ASCs, Stratified by U.S. Census Region From 2018 to 2022
Charge Differences by Payer, Region, and Season
Inflation-adjusted mean charges increased over the study period, from $30,600 in 2018 to $42,300 in 2021 (P < 0.001). Charge differences were observed across payer types (F = 49.06, P < 0.001). Self-pay patients incurred the highest geometric mean charges ($70,000; 95% CI $64,200–$76,700), which were 105% higher than Medicare, and 74-75% higher than private insurance, other insurance, and Medicaid (P < 0.001 for all comparisons; Table 2). Medicare had the lowest charges ($34,300; 95% CI $32,500–$36,700), while private insurance, other insurance, and Medicaid clustered around $40,000–$40,500 (Table 3).
Table 2.
Mean Adjusted Total Charges and Statistical Significance
| Factor | Category | Mean log cost a [95% CI] | Estimated cost ($) b [95% CI] | Overall F-test c | P value |
|---|---|---|---|---|---|
| Payer | F = 49.06 | <0.001 | |||
| Self-pay | 11.16 [11.08, 11.25] | $70,011 [$64,208–$76,682] | |||
| Private insurance | 10.61 [10.57, 10.65] | $40,485 [$38,873–$42,602] | |||
| Other | 10.61 [10.53, 10.69] | $40,485 [$37,779–$44,056] | |||
| Medicaid | 10.60 [10.50, 10.70] | $40,049 [$36,656–$44,849] | |||
| Medicare | 10.44 [10.39, 10.50] | $34,281 [$32,481–$36,667] | |||
| Region | F = 293.49 | < 0.001 | |||
| West | 11.13 [11.08, 11.17] | $68,681 [$64,208–$71,931] | |||
| South | 10.40 [10.36, 10.44] | $32,974 [$31,521–$34,465] | |||
| Northeast | 10.40 [10.35, 10.45] | $32,974 [$31,414–$34,809] | |||
| Midwest | 10.38 [10.34, 10.42] | $32,316 [$30,922–$33,706] | |||
| Season | F = 1.30 | 0.273 | |||
| Winter | 10.61 [10.56, 10.66] | $40,485 [$38,713–$42,652] | |||
| Fall | 10.61 [10.56, 10.66] | $40,485 [$38,713–$42,652] | |||
| Summer | 10.59 [10.54, 10.65] | $39,680 [$37,931–$42,102] | |||
| Spring | 10.55 [10.50, 10.60] | $38,053 [$36,656–$40,150] |
95% CI = 95% confidence interval; $ = United States dollars; % = percentage. Significance was set at the P < 0.05 level.
aLog-transformed costs estimated from survey-weighted generalized linear models (GLMs); values represent geometric means.
bBack-transformed from log scale to original dollar scale using exponentiation; 95% CIs reflect geometric mean costs.
cDesign-based Wald F-test from survey-weighted GLM; tests for overall group differences.
Table 3.
Significant Overall Cost Differences (Pairwise Comparisons)
| Group | Comparator | Log cost difference a | Dollar difference b | P value | Relative cost difference c |
|---|---|---|---|---|---|
| Self-pay | Medicare | +0.72 | +$36,321 | < 0.001 | Higher by 105% |
| Private insurance | +0.55 | +$29,658 | < 0.001 | Higher by 74% | |
| Other | +0.55 | +$29,658 | < 0.001 | Higher by 74% | |
| Medicaid | +0.56 | +$30,119 | < 0.001 | Higher by 75% | |
| Medicare | Private insurance | −0.16 | -$6663 | < 0.001 | Lower by 15% |
| Other | −0.17 | -$6663 | 0.012 | Lower by 15% | |
| West | Midwest | +0.75 | +$35,856 | < 0.001 | Higher by 111% |
| Northeast | +0.72 | +$34,853 | < 0.001 | Higher by 106% | |
| South | +0.72 | +$34,853 | < 0.001 | Higher by 106% |
aEstimates from survey-weighted GLM on log-transformed costs.
bDollar values back-transformed from log scale.
cRelative differences computed against comparator group.
Significance was set at the P < 0.05 level.
Regional differences were also pronounced (F = 293.49, P < 0.001). The West had the highest estimated charges ($68,700; 95% CI $64,200–$71,900), exceeding those in the Midwest by 111% and those in the Northeast and South by 106% (P < 0.001 for all). No differences in charges were observed by season (F = 1.30, P = 0.273), with seasonal estimates ranging from $38,000 in spring to $40,500 in winter and fall.
Volume Distribution by Payer, Region, and Season
Private insurance accounted for the highest overall procedure volume (1420.9; 95% CI 1354.4-1487.4), which was more than Medicare (964.6), Medicaid (217.3), or self-pay (179.6; P < 0.001). These patterns are visually summarized in Figure 2. Regionally, the South had the highest overall volume (987.2; 95% CI 920.5-1053.9), followed by the West (822.8), Northeast (743.1), and Midwest (544.4; P < 0.001). No changes in seasonal variation in volume were observed (P > 0.05), with estimates ranging from 710.4 in winter to 810.3 in spring (Table 4).
Figure 2.
Weighted Procedure Volume by Primary Payer From 2018 to 2022
Table 4.
Overall Procedure Volume and Key Comparisons
| Factor | Category | Mean volume a [95% CI] | Key significant comparisons b |
|---|---|---|---|
| Payer | |||
| Private insurance | 1420.9 [1354.4-1487.4] | vs All others: P < 0.001 | |
| Medicare | 964.6 [904.8-1024.4] | vs Medicaid/Self-pay: P < 0.001 | |
| Other | 315.1 [276.2-354.0] | vs Medicaid/Self-pay: P < 0.05 | |
| Medicaid | 217.3 [185.1-249.5] | ||
| Self-pay | 179.6 [150.7-208.5] | ||
| Region | |||
| South | 987.2 [920.5-1053.9] | vs All others: P < 0.001 | |
| West | 822.8 [762.6-883.0] | vs Midwest/Northeast: P < 0.05 | |
| Northeast | 743.1 [690.1-796.1] | vs Midwest: P < 0.001 | |
| Midwest | 544.4 [503.0-585.8] | ||
| Season | |||
| Spring | 810.3 [752.0-868.6] | No significant differences (all P > 0.05) | |
| Summer | 792.0 [736.7-847.3] | ||
| Fall | 784.8 [729.3-840.3] | ||
| Winter | 710.4 [654.9-765.9] |
95% CI = 95% confidence interval. Significance was set at the P < 0.05 level.
aMean annual procedure volume estimated using survey-weighted totals.
bBonferroni correction applied for multiple comparisons.
Temporal Trends in Charges and Volume
Over time, inflation-adjusted charges increased across all payer groups. However, there was no observed effect on the payer-by-year interaction (P = 0.445). Self-pay patients had the steepest charge growth (+8.5% per year), followed by other insurance (+4.6%), private insurance (+4.5%), and Medicare (+3.8%). Regionally, the South showed a +3.3% annual increase in charges, the Northeast +0.6%, and the West a slight decline (−1.7%), though these trends were not significant (P = 0.161).
By contrast, increases in volume regionally were observed (P = 0.002). Relative to the Midwest reference, the West exhibited the most robust growth (+63.97 procedures per year), followed by the Northeast (+13.25) and South (+5.22; Table 5).
Table 5.
Temporal Trends in Adjusted Cost and Procedure Volume by Group
| Domain | Factor | Category | Annual trend a | Between-group interaction P value b |
|---|---|---|---|---|
| Cost | Payer | 0.445 | ||
| Medicaid | Ref | |||
| Self-pay | +8.5% | |||
| Private insurance | +4.5% | |||
| Medicare | +3.8% | |||
| Other | +4.6% | |||
| Region | 0.161 | |||
| Midwest | Ref | |||
| South | +3.3% | |||
| West | −1.7% | |||
| Northeast | +0.6% | |||
| Season | 0.186 | |||
| Winter | Ref | |||
| Spring | +8.9% | |||
| Summer | +4.9% | |||
| Fall | +5.6% | |||
| Volume | Payer | 0.292 | ||
| Medicaid | Ref | |||
| Self-pay | +7.21 | |||
| Private insurance | +9.64 | |||
| Medicare | +19.01 | |||
| Other | −0.97 | |||
| Region | 0.002 | |||
| Midwest | Ref | |||
| South | +5.22 | |||
| West | +63.97 | |||
| Northeast | +13.25 | |||
| Season | 0.993 | |||
| Winter | Ref | |||
| Spring | −1.31 | |||
| Summer | −4.10 | |||
| Fall | −3.65 |
Ref = Reference; % = percentage. Significance was set at the P < 0.05 level.
aAnnual trend reflects the average yearly change: in cost models, this represents percent change in inflation-adjusted cost relative to the reference group; in volume models, this represents the absolute change in number of procedures per year relative to the reference group.
bOnly the Region × Year interaction in the volume model was statistically significant (P = 0.002), indicating differing volume trends by region.
Primary Diagnoses
The most common primary indication was lumbar disc disorder with radiculopathy, followed by other disc displacement and lumbar spinal stenosis without claudication. These findings suggest that most endoscopic lumbar decompression cases were performed for degenerative and radicular conditions (Figure 3).
Figure 3.
Top 10 Weighted Primary Diagnoses for Endoscopic Spine Procedures From 2018 to 2022
Discussion
Endoscopic lumbar decompression continues to gain recognition as a minimally invasive alternative for the treatment of lumbar disc herniation and spinal stenosis. In this nationally representative study of hospital-owned ASCs, we observed modest but notable growth in endoscopic lumbar decompression procedures from 2018 to 2022, with procedure volume increasing particularly in the western United States. Inflation-adjusted charges also rose over the study period, especially among self-pay and privately insured patients. These results demonstrate differential growth in utilization and marked variation in facility charges by payer and region, with implications for access and affordability. They also indicate ongoing shifts in the adoption and cost structure of endoscopic lumbar decompression, offering insight into payer dynamics, regional disparities, and emerging access trends within the outpatient setting.
We found a steady increase in national volume, with a substantial rise in both the total number of endoscopic lumbar decompression procedures and average adjusted charges, peaking at over $42,000 in 2021. Prior research has indicated increasing utilization of minimally invasive lumbar decompression procedures nationwide, primarily due to the favorable outcomes including reduced postoperative complications and shorter hospital stays compared to traditional open techniques.5-7 Our findings focus on economics rather than effectiveness. Rising charges occurred alongside greater use, which may reflect higher costs for disposable instruments, expenses related to endoscopic platforms, and variability in payer contracting. Strategies such as improving payer contracting practices, adopting value-based purchasing for disposables, and increasing transparency around charge schedules may help moderate facility charges while maintaining access.
Private insurers represented the predominant payer, although the most striking growth occurred among self-pay patients, who incurred higher charges compared to other payer groups undergoing endoscopic lumbar decompression. This trend is consistent with prior studies identifying pronounced variability in reimbursement and out-of-pocket burden for ESS procedures across payer categories, highlighting an area for potential healthcare policy intervention to alleviate patient financial strain.18,19,22 Geographically, the West region exhibited both the greatest procedural growth and highest mean charges, reflecting concentrated regional investments and greater adoption of minimally invasive techniques consistent with recent national analyses of spine surgery utilization patterns. 17 Vemu et al 15 similarly reported pronounced regional variability in ESS adoption across the United States, with differential growth rates possibly driven by regional investments in technology and training. Seasonal differences were negligible, reinforcing the year-round stability and consistency of ESS as an outpatient procedure. Market-level factors such as coverage policies, allowable charge schedules, and the local supply of endoscopy-trained surgeons plausibly underlie these payer and regional differences. From an equity standpoint, inconsistent prior-authorization and site-of-service approvals may shift endoscopic care toward self-pay or out-of-network settings, increasing patient financial exposure and limiting uptake among Medicaid and underinsured patients. Given the steep rise in self-pay utilization and the concentration of higher charges in the West, payer alignment on coverage criteria and site-of-service policies in high-growth markets could reduce patient exposure to facility charges while preserving access.
Although endoscopic lumbar decompression remained more common in urban and higher-income populations, we observed meaningful growth in rural utilization, suggesting improving access and broader dissemination into historically underserved communities. Despite these trends, disparities persist, underscoring the need for continued efforts toward equitable surgical care access.1,2 Targeted steps such as clearer coding guidance, payer alignment for prior authorization, and supported training pathways in low-capacity regions may help reduce access and reimbursement gaps. Recent systematic reviews and comparative analyses report favorable outcomes for endoscopic spine surgery compared with open procedures, including lower infection risk, reduced intraoperative blood loss, and shorter recovery, which supports expansion across diverse clinical settings.11,23,24 Nonetheless, regional differences in growth point to the value of focused training initiatives and standardized educational programs to address barriers to adoption, including surgeon training gaps and procedural complexity. 14 Alostaz et al similarly highlighted limited training opportunities and concerns about complexity as primary barriers, reinforcing the need for targeted educational efforts. 25
This study has several limitations inherent to the use of the NASS database. In real-world practice, reimbursement and coding patterns can lead to under-ascertainment of endoscopic lumbar decompressions (particularly biportal), as some cases are billed under open or microscopic CPT codes, biasing endoscopic volumes downward. Because NASS captures only hospital-owned ASCs, national estimates may underrepresent true procedural volumes, particularly in regions with high concentrations of physician-owned facilities where ESS adoption may be greater. 20 Generalizability may be limited. Physician-owned ASCs can differ from hospital-owned centers in payer mix, allowable charge structures, coding and billing practices, case selection, and the pace of endoscopic technology adoption. These differences may lead to underestimation of real-world endoscopic lumbar decompression uptake and, if hospital-owned facilities tend to have higher charge schedules, overestimation of average charges relative to physician-owned sites. In addition, hospital-owned ASCs are concentrated in urban areas, which may underrepresent rural encounters in NASS and could lead to understatement of rural utilization and different charge patterns, thereby limiting generalizability to rural markets. While CPT-based coding ensures consistent identification of procedures, it does not capture important intraoperative details such as laterality, surgical modifications such as conversion from discectomy to foraminotomy, or implant use. Moreover, the database contains only encounter-level data, preventing longitudinal tracking of outcomes, revisions, or complications. Cost data reflect facility-reported total charges rather than economic costs or payer reimbursements and exclude professional (surgeon/anesthesia) fees. As a result, they do not account for post-discharge resource utilization.
Conclusions
Our study provides a comprehensive overview of recent trends in endoscopic lumbar decompression utilization and charges within hospital-owned ASCs. Across 3097 procedures from 2018 to 2022, 93.5% occurred in urban settings and private insurance accounted for 45.8% of cases, while self-pay utilization increased from 0.8% in 2018 to 9.7% in 2022. The observed increase in procedural volumes and associated facility charges underscores growing adoption and an evolving economic landscape, with the West increasing from 4.3% of national volume in 2018 to 31.0% in 2022 and the highest estimated charges observed among self-pay patients at $70,000 and in the West at $68,700. Although disparities in access and reimbursement persist, endoscopic lumbar decompression offers efficiency advantages that support outpatient care. All cases in this analysis were performed in hospital-owned ambulatory surgery centers because the NASS database includes only hospital-owned facilities, which may underrepresent rural markets and regions with a high concentration of physician-owned centers. Future initiatives should focus on addressing regional variability, improving charge transparency, and expanding standardized training pathways to facilitate broader adoption and equitable access.
Appendix.
Appendix 1. Year-Specific Thresholds for Income Quartiles From 2018 to 2022
| Year | Q1 ($) | Q2 ($) | Q3 ($) | Q4 ($) |
|---|---|---|---|---|
| 2018 | 1-45,999 | 46,000-58,999 | 59,000-78,999 | 79,000+ |
| 2019 | 1-47,999 | 48,000-60,999 | 61,000-81,999 | 82,000+ |
| 2020 | 1-49,999 | 50,000-64,999 | 65,000-85,999 | 86,000+ |
| 2021 | 1-51,999 | 52,000-65,999 | 66,000-87,999 | 88,000+ |
| 2022 | 1-55,999 | 56,000-70,999 | 71,000-93,999 | 94,000+ |
Q = Quarter; $ = United States dollars.
Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article.
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Disclosures: Mitchell K. Ng has the following disclosures: VB Spine (paid consultant), Stryker Inc. (paid consultant), Johnson & Johnson Ethicon Inc. (paid consultant), Elevation Spine (paid consultant), CurvaFix Inc. (paid consultant), Pacira BioSciences Inc. (paid consultant), Sage Products Inc. (paid consultant), Alafair Biosciences Inc. (paid consultant), Next Science LLC (paid consultant), Bonutti Technologies Inc. (paid consultant), Hippocrates Opportunities Fund LLC (paid consultant), MM Labs (paid consultant), and Ferghana Partners Inc. (paid consultant). Afshin E. Razi has the following disclosures: 4D Motion (IP royalties), Clinical Orthopaedic Society (fiduciary officer; president; board of directors/committee member), and New York State Society of Orthopaedic Surgeons (fiduciary officer; secretary; board of directors/committee member). Ian D. Kaye has the following disclosures: Camber Spine (IP royalties; paid consultant; research support), Johnson & Johnson (paid consultant), North American Spine Society (board or committee member), NuVasive (paid consultant), Spinal Cord and Case Series (editorial or governing board), and Thieme (publishing royalties; financial or material support). Barrett Woods has the following disclosures: Harmoni Neuromonitoring (IP royalties), Altus Partners LLC (IP royalties), and J. Robert Gladden Society (chair of research; board of directors/committee member). Mark F. Kurd has the following disclosures: DuraStat LLC (stock or stock options), K2M Spine (paid consultant), Medtronic (paid consultant), Spinal Elements (IP royalties), Stryker (IP royalties), and The Institute for Musculoskeletal Science & Education (IP royalties). Jose A. Canseco has the following disclosures: Accelus (research support), Cervical Spine Research Society (board or committee member), PathKeeper Surgical (stock or stock options; unpaid consultant), and Wolters Kluwer Health – Lippincott Williams & Wilkins (editorial or governing board). Alan S. Hilibrand has the following disclosures: CTL Amedica (IP royalties), North American Spine Society (board or committee member), Paradigm Spine (stock or stock options), and ZimVie (IP royalties). Thomas D. Cha has the following disclosures: Globus Medical (paid consultant), K2M (research support), Kuros (stock or stock options), NuVasive (research support), and Stryker (paid consultant). Alan S. Hilibrand has the following disclosures: CTL Amedica (IP royalties), North American Spine Society (board or committee member), Paradigm Spine (stock or stock options), and ZimVie (IP royalties). Alexander R. Vaccaro has the following disclosures: Accelus (other financial or material support; stock or stock options), Advanced Spinal Intellectual Properties (stock or stock options), AO Spine (other financial or material support), Atlas Spine (stock or stock options), Avaz Surgical (stock or stock options), AVKN Patient Driven Care (stock or stock options), Cytonics (stock or stock options), Deep Health (stock or stock options), Dimension Orthotics LLC (stock or stock options), Electrocore (stock or stock options), Elsevier (publishing royalties, financial or material support), Flagship Surgical (stock or stock options), FlowPharma (stock or stock options), Globus Medical (stock or stock options), Harvard Medtech (stock or stock options), Innovative Surgical Design (stock or stock options), Jaypee (publishing royalties, financial or material support), Jushi (Haywood) (stock or stock options), National Spine Health Foundation (board or committee member), Nuvasive (stock or stock options), Orthobullets (stock or stock options), Parvizi Surgical Innovation (stock or stock options), Progressive Spinal Technologies (stock or stock options), Rothman Institute and Related Properties (stock or stock options), Sentryx (other financial or material support; stock or stock options), Stout Medical (stock or stock options), Taylor Francis/Hodder and Stoughton (publishing royalties, financial or material support), Thieme (publishing royalties, financial or material support), and ViewFi Health (stock or stock options). Gregory D. Schroeder has the following disclosures: Advance Medical (paid consultant), Bioventus (paid consultant), Surgalign (paid consultant), AO Spine (board or committee member; other financial or material support), Cervical Spine Research Society (board or committee member), Cerapedics (research support), DePuy, A Johnson & Johnson Company (research support), Medtronic Sofamor Danek (research support), and Wolters Kluwer Health – Lippincott Williams & Wilkins (editorial or governing board). Christopher K. Kepler has the following disclosures: Clinical Spine Surgery (editorial or governing board; section editor), Curetiva (IP royalties), Regeneration Technologies, Inc. (IP royalties), Altus Partners LLC (stock), and Harmoni (stock).
ORCID iDs
Mitchell K. Ng https://orcid.org/0000-0002-5831-055X
Paul G. Mastrokostas https://orcid.org/0000-0002-1196-517X
Leonidas E. Mastrokostas https://orcid.org/0009-0006-8926-3502
William Green https://orcid.org/0000-0001-7147-0542
Rajendra Singh https://orcid.org/0000-0003-3308-5832
Jose A. Canseco https://orcid.org/0000-0002-2152-5725
Alan S. Hilibrand https://orcid.org/0000-0001-8811-9687
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