TABLE IV.
Two-Year Treatment Effects by Disc Herniation Level*
| Treatment Effect
|
Comparison of Herniation Levels (p value)
|
|||||
|---|---|---|---|---|---|---|
| Upper Level Herniation (N = 88) | L4-L5 (N = 455) | L5-S1 (N = 643) | Upper Levels and L4-L5 | Upper Levels and L5-S1 | L4-L5 and L5-S1 | |
| SF-36 bodily pain score | 24.6 (13.2, 36) | 11.6 (7, 16.1) | 7.1 (3.1, 11.1) | 0.018 | 0.002 | 0.073 |
| SF-36 physical functioning score | 23.4 (11.9, 34.9) | 17.1 (12.8, 21.4) | 9.9 (6.2, 13.6) | 0.16 | 0.014 | 0.006 |
| Oswestry Disability Index | −19 (−27.7, −10.2) | −13.8 (−17.3, −10.3) | −10.3 (−13.4, −7.2) | 0.14 | 0.033 | 0.073 |
*
Treatment effect is defined as the change in the operative group minus the change in the nonoperative group. As-treated randomized and observational cohorts combined, adjusted for age, gender, race, marital status, work status, disability compensation status, body mass index, smoking, joint problems, migraines, any neurological deficit, herniation (type and location), baseline score, baseline leg-symptom severity, baseline satisfaction with symptoms, self-rated health trend, center, and insurance. Upper level herniations are at L2-L3 and L3-L4. SF-36 = Short Form-36.