Understanding the Trends and Variability in Procedures Performed During Orthopedic Spine Surgery Fellowship Training: An Analysis of ACGME Case Log Data

Establishing case volume benchmarks for ACGME-accredited orthopedic surgery of the spine fellowship training

BACKGROUND CONTEXT

There has been increasing scrutiny on the standardization of surgical training in the US.

PURPOSE

This study provides case volume benchmarks for Accreditation Council for Graduate Medical Education (ACGME)-accredited orthopedic spine surgery fellowship training.

STUDY DESIGN/SETTING

This was a retrospective cross-sectional study of fellows at ACGME-accredited orthopedic spine surgery fellowships (2017-2022).

PATIENT SAMPLE

N/A.

OUTCOME MEASURES

Reported case volume during fellowship training.

METHODS

Case volume percentiles were calculated across ACGME-defined case categories and temporal changes assessed via linear regression. Variability between the highest and lowest deciles by case volume was calculated as fold-differences (90th percentile/10th percentile). Sensitivity analyses were performed to identify potential targets for case minimum requirements.

RESULTS

A total of 163 spine surgery fellows were included in this study. Total mean reported spine surgery case volume increased from 313.2±122 in 2017 to 382.0±164 in 2022 (p=.19). Most cases were classified as adult (range, 97.2%-98.0%) over pediatric cases (range, 2.0%-2.8%). An average of 322.0 cases were reported and most were classified as laminectomy (32%), posterior arthrodesis (29%), and anterior arthrodesis (20%). Overall variability in total case volume was 2.4 and the greatest variability existed for posterior instrumentation (38.1), application of cage (34.6), anterior instrumentation (20.8), and fractures and dislocations (17.3). If case minimum requirements for total reported cases was assumed at 200 cases, then all spine fellows included in this study would achieve this requirement. However, if case minimum requirements were assumed at 250 total cases, then approximately thirty percent of fellows (n=49) would not achieve this requirement for graduation.

CONCLUSIONS

Increasingly, national societies and accrediting bodies for surgical education recognize the need for standardized training. This study provides benchmarks to inform potential case minimum requirements and help reduce variability during spine fellowship training. Future studies are needed to establish case minimum requirements for spine surgery fellowship training across comprehensive and granular case categories that cover the full gamut of orthopedic spine surgery.

Understanding Geospatial Trends in Lumbar Fusion Incidence and Technique in Medicare Populations

STUDY DESIGN

Retrospective study with epidemiologic analysis of public Medicare data.

OBJECTIVE

This study seeks to utilize geospatial analysis to identify distinct trends in lumbar fusion incidence and techniques in Medicare populations.

SUMMARY OF BACKGROUND DATA

With an aging population and new technologies, lumbar fusion is an increasingly common procedure. There is controversy, however, regarding which indications and techniques achieve optimal outcomes, leading to significant intersurgeon variation and potential national disparities in care.

MATERIALS AND METHODS

Medicare billing datasets were supplemented with Census Bureau socioeconomic data from 2013 to 2020. These databases listed lumbar fusions billed to Medicare by location, specialty, and technique. Hotspots and coldspots of lumbar fusion incidence and technique choice were identified with county-level analysis and compared with Mann-Whitney U . A linear regression of fusion incidence and a logistic regression of lumbar fusion hotspots/coldspots were also calculated.

RESULTS

Between 2013 and 2020, 624,850 lumbar fusions were billed to Medicare. Lumbar fusion hotspots performed fusions at nearly five times the incidence of coldspots (101.6-21.1 fusions per 100,000 Medicare members) and were located in the Midwest, Colorado, and Virginia while coldspots were in California, Florida, Wisconsin, and the Northeast. Posterior and posterolateral fusion were the most favored techniques, with hotspots in the Northeast. Combined posterior and posterolateral fusion and posterior interbody fusion was the second most favored technique, predominantly in Illinois, Missouri, Arkansas, and Colorado.

CONCLUSIONS

The geographic distribution of lumbar fusions correlates with variations in residency training, fellowship, and specialty. The geospatial patterning in both utilization and technique reflects a lack of consensus in the application of lumbar fusion. The strong variance in utilization is a potentially worrying finding that could suggest that the nonstandardization of lumbar fusion indication has led to both overtreatment and undertreatment across the nation.

LEVEL OF EVIDENCE

Level 3-retrospective.

Impact of Specialty on Cases Performed During Spine Surgery Training in the United States

OBJECTIVE

Two general pathways exist for spine surgery training in the United States: orthopedic surgery and neurological surgery. Previous studies have not quantified the impact of fellowship training when comparing case volumes between these 2 training pathways. This study compares reported spine surgery case volume upon graduation from orthopedic surgery and neurological surgery training.

METHODS

This was a retrospective cohort study of recent graduates from orthopedic surgery and neurological Surgery training programs in the United States (2018-2021). The Accreditation Council for Graduate Medical Education provided case logs for residents in neurological surgery and orthopedic surgery as well as fellows in orthopedic spine surgery. Case volumes were compared for adult and pediatric spine surgery cases using parametric tests.

RESULTS

Case logs from 3146 orthopedic surgery residents, 107 orthopedic spine surgery fellows, and 766 neurological surgery residents were included in this study. Across each cohort, neurological surgery trainees reported more total adult spine surgery cases than orthopedic surgery trainees (514 ± 206 vs. 383 ± 171, P < 0.001). Orthopedic surgery trainees reported more total pediatric spine surgery cases (21 ± 14 vs. 17 ± 12, P = 0.006).

CONCLUSIONS

Neurological surgery training affords a greater volume of adult spine surgery cases, but orthopedic surgery affords more pediatric spine surgery cases. Identification of relative strengths and weaknesses can help facilitate multidisciplinary training experiences in spine surgery.

Utility of Spine Surgery Fellowship Training for Orthopaedic Surgeons in the United States

INTRODUCTION

Orthopaedic spine surgeons gain surgical experience through cases conducted during residency and fellowship training. This study elucidates the incremental benefit in spine surgery volume from orthopaedic spine surgery fellowship training.

METHODS

This was a retrospective national cohort study of orthopaedic surgery residents and orthopaedic spine surgery fellows graduating from US Accreditation Council for Graduate Medical Education-accredited training programs during the 2017 to 2020 academic years. Comparisons in spine surgery case volume were made with parametric tests.

RESULTS

One hundred fourteen spine surgery fellows and 3,000 orthopaedic surgery residents were included. There was a 3.5-fold increase in total spine surgery cases conducted during fellowship versus residency (314 ± 129 vs. 89 ± 61, P < 0.001). Spine surgery fellows one standard deviation more than the mean reported 443 total spine cases. The largest differences between fellows and residents were Decompression (104 ± 48 vs. 28 ± 23, P < 0.001), Posterior Arthrodesis (94 ± 46 vs. 21 ± 18, P < 0.001), Anterior Arthrodesis (64 ± 31 vs. 13 ± 13, P < 0.001), and Instrumentation (43 ± 25 vs. 22 ± 12, P < 0.001).

DISCUSSION

Spine surgery fellowship training affords orthopaedic surgeons the opportunity to increase spine surgery case volume by over threefold. The greatest increases in case volume were reported for Decompression, Posterior Arthrodesis, Anterior Arthrodesis, and Instrumentation.