Study Design. Concurrent, prospective, randomized, and observational cohort study.
Objective. To assess the 4-year outcomes of surgery versus nonoperative care.
Summary of Background Data. Although randomized trials have demonstrated small short-term differences in favor of surgery, long-term outcomes comparing surgical to nonoperative treatment remain controversial.
Methods. Surgical candidates with imaging-confirmed lumbar intervertebral disc herniation meeting SPORT eligibility criteria enrolled into prospective, randomized (501 participants), and observational cohorts (743 participants) at 13 spine clinics in 11 US states. Interventions were standard open discectomy versus usual nonoperative care. Main outcome measures were changes from baseline in the SF-36 Bodily Pain (BP) and Physical Function (PF) scales and the modified Oswestry Disability Index (ODI - AAOS/Modems version) assessed at 6 weeks, 3 months, 6 months, and annually thereafter.
Results. Nonadherence to treatment assignment caused the intent-to-treat analyses to underestimate the treatment effects. In the 4-year combined as-treated analysis, those receiving surgery demonstrated significantly greater improvement in all the primary outcome measures (mean change surgery vs. nonoperative; treatment effect; 95% CI): BP (45.6 vs. 30.7; 15.0; 11.8 to 18.1), PF (44.6 vs. 29.7; 14.9;12.0 to 17.8) and ODI (−38.1 vs. −24.9; −13.2; −15.6 to −10.9). The percent working was similar between the surgery and nonoperative groups, 84.4% versus 78.4% respectively.
Conclusion. In a combined as-treated analysis at 4 years, patients who underwent surgery for a lumbar disc herniation achieved greater improvement than nonoperatively treated patients in all primary and secondary outcomes except work status.
Four-year results of the Spine Patient Outcomes Research Trial (SPORT) are detailed, including discussion of crossover and comparisons to other similar trials. At 4 years, patients who had surgery for intervertebral disc herniation maintained greater improvement in all primary outcomes compared to those who remained nonoperative.
From the *Dartmouth Medical School, Hanover, NH; William Beaumont Hospital, Royal Oak, MI; and Rothman Institute, Philadelphia, PA.
Acknowledgment date: July 24, 2008. First revision date: September 22, 2008. Acceptance date: September 23, 2008.
The manuscript submitted does not contain information about medical device(s)/drug(s).
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.
This study is under annual review by the Dartmouth Committee for the Protection of Human Subjects (CPHS #17083).
Funding: The National Institute of Arthritis and Musculoskeletal and Skin Diseases (U01-AR45444-01A1) and the Office of Research on Women’s Health, the National Institutes of Health, and the National Institute of Occupational Safety and Health, the Centers for Disease Control and Prevention. The Multidisciplinary Clinical Research Center in Musculoskeletal Diseases is funded by NIAMS (P60-AR048094-01A1). Dr. Lurie is supported by a Research Career Award from NIAMS (1 K23 AR 048138-01).
Trial Registration: Spine Patient Outcomes Research Trial (SPORT): Intervertebral Disc Herniation; #NCT00000410; http://www.clinicaltrials.gov/ct/show/NCT00000410?order=2.
Address correspondence to James N. Weinstein, DO, MS, Director, The Dartmouth Institute for Health Policy and Clinical Practice, Dartmouth College, Professor & Chair, Department of Orthopaedics, Dartmouth Medical School, One Medical Center Dr., Lebanon, NH 03756, 603-653-3580, 603-653-3581; E-mail:SPORT@dartmouth.edu