Study Design. Retrospective cohort study using national sample administrative data.
Objectives. To determine if lumbar fusion rates increased in the 1990s and to compare lumbar fusion rates with those of other major musculoskeletal procedures.
Summary of Background Data. Previous studies found that lumbar fusion rates rose more rapidly during the 1980s than did other types of lumbar surgery.
Methods. We used the Healthcare Cost and Utilization Project Nationwide Inpatient Sample from 1988 through 2001 to examine trends. U.S. Census data were used for calculating age and sex-adjusted population-based rates. We excluded patients with vertebral fractures, cancer, or infection.
Results. In 2001, over 122,000 lumbar fusions were performed nationwide for degenerative conditions. This represented a 220% increase from 1990 in fusions per 100,000. The increase accelerated after 1996, when fusion cages were approved. From 1996 to 2001, the number of lumbar fusions increased 113%, compared with 13 to 15% for hip replacement and knee arthroplasty. Rates of lumbar fusion rose most rapidly among patients aged 60 and above. The proportion of lumbar operations involving a fusion increased for all diagnoses.
Conclusions. Lumbar fusion rates rose even more rapidly in the 90s than in the 80s. The most rapid increases followed the approval of new surgical implants and were much greater than increases in other major orthopedic procedures. The most rapid increases in fusion rates were among adults aged 60 and above. These increases were not associated with reports of clarified indications or improved efficacy, suggesting a need for better data on the efficacy of various fusion techniques for various indications.
Lumbar fusion surgery rates rose rapidly in the 1990s and accelerated after approval of intervertebral fusion cages. The rise exceeded increases in some other major orthopedic procedures and was greatest among older adults. The dramatic rise in fusion surgery rates suggests a need to better define the indications for lumbar fusion.
From the *Departments of Medicine, †Health Services, ‡Orthopaedics and Sports Medicine, and the §Center for Cost and Outcomes Research, University of Washington, Seattle, Washington; and the ¶Center for Quality Improvement and Patient Safety, Agency for Healthcare Research and Quality, Rockville, Maryland.
Supported by Grant P60 AR 48093 from the National Institute for Arthritis, Musculoskeletal and Skin Diseases.
The statewide data organizations that participated in the HCUP NIS 2001: Arizona Department of Health Services; California Office of Statewide Health Planning & Development; Colorado Health & Hospital Association; Connecticut -Chime, Inc.; Florida Agency for Health Care Administration; Georgia -GHA, an association of Hospitals & Health Systems; Hawaii Health Information Corporation; Illinois Health Care Cost Containment Council; Iowa Hospital Association; Kansas Hospital Association; Kentucky Department for Public Health; Maine Health Data Organization; Maryland Health Services Cost Review Commission; Massachusetts Division of Health Care Finance and Policy; Michigan Health and Hospital Association; Minnesota Hospital Association; Missouri Hospital Industry Data Institute; Nebraska Hospital Association; New Jersey Department of Health & Senior Services; New York State Department of Health; North Carolina Department of Health and Human Services; Oregon Association of Hospitals & Health Systems; Pennsylvania Health Care Cost Containment Council; Rhode Island Department of Health; South Carolina State Budget & Control Board; Tennessee Hospital Association; Texas Health Care Information Council; Utah Department of Health; Vermont Association of Hospitals and Health Systems; Virginia Health Information; Washington State Department of Health; West Virginia Health Care Authority; and Wisconsin Department of Health & Family Services.
The conclusions and opinions presented here are those of the authors and not necessarily those of the National Institutes of Health or the Agency for Healthcare Research and Quality.
Acknowledgment date: November 17, 2004. Acceptance date: January 7, 2005.
The device(s)/drug(s) is/are FDA-approved or approved by corresponding national agency for this indication.
Federal funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript.
Address correspondence and requests for reprints to Richard A. Deyo, MD, MPH, UW Center for Cost and Outcomes Research, 325 Ninth Avenue, Box 359736, Seattle, WA 98104; E-mail: email@example.com.