Subgroup analyses according to treatment received.
To evaluate whether baseline radiographic findings predicted outcomes in patients with degenerative spondylolisthesis.
The spine patient outcomes research trial combined randomized and observational DS cohorts.
The Meyerding listhesis grade was determined on the neutral radiograph (n = 222). Patients were classified as having low disc height if disc height was less than 5 mm. Flexion-extension radiographs (n = 185) were evaluated for mobility. Those with greater than 10° rotation or 4 mm translation were considered hypermobile. Changes in outcome measures were compared between listhesis (grade 1 vs. grade 2), disc height (low vs. normal), and mobility (stable vs. hypermobile) groups using longitudinal regression models adjusted for potential confounders. Outcome measures included SF-36 bodily pain and physical function scales, oswestry disability index (ODI), stenosis bothersomeness index, and low back pain bothersomeness scale.
Overall, 86% had a grade 1 listhesis, 78% had normal disc height, and 73% were stable. Baseline symptom severity was similar between groups. Overall, surgery patients improved more than patients treated nonoperatively. At 1 year, outcomes were similar in surgery patients across listhesis, disc height, and mobility groups (ODI: grade 1 −23.7 vs. grade 2 −23.3, P = 0.90; normal disc height −23.5 vs. low disc height −21.9, P = 0.66; stable −21.6 vs. hypermobile −25.2, P = 0.30). Among those treated nonoperatively, grade 1 patients improved more than grade 2 patients (bodily pain + 13.1 vs. −4.9, P = 0.019; ODI −8.0 vs. + 4.8, P = 0.010 at 1 year), and hypermobile patients improved more than stable patients (ODI −15.2 vs. −6.6, P = 0.041; stenosis bothersomeness index −7.8 vs. −2.7, P = 0.002 at 1 year).
Regardless of listhesis grade, disc height or mobility, patients who had surgery improved more than those treated nonoperatively. These differences were due, in part, to differences in nonoperative outcomes, which were better in patients classified as grade 1 or hypermobile.
Baseline radiographs of patients with degenerative spondylolisthesis were evaluated for predictability of outcomes. Regardless of listhesis grade, disc height or mobility, patients who had surgery improved more than those treated nonoperatively.
From the *Dartmouth Medical School, Lebanon, NH; †Helios-Rosmann-Hospital, Breisach, Germany; ‡Rush University Medical Center, Chicago, IL; and §Hospital for Special Surgery, New York, NY.
Acknowledgment date: October 17, 2007. Acceptance date: January 21, 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.
The authors received funding from the following sources: 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. Pearson was funded by NIAMS (T32-AR-049710). Dr. Lurie received support from a Research Career Award from NIAMS (1 K23 AR 048138-01).
Address correspondence and reprint requests to Adam M. Pearson, MD, MS, Department of Orthopaedics, Dartmouth-Hitchcock Medical Center, One Medical Center Dr., Lebanon, NH 03756; E-mail: email@example.com