TABLE III.
Adjusted Change Scores and Treatment Effects for the Intervertebral Disc Herniation Randomized and Observational Cohorts According to Treatment Received and Herniation Level*
| Baseline
|
3-Mo Evaluation
|
1-Yr Evaluation
|
2-Yr Evaluation
|
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Group According to Herniation Level | Op. Treatment | Nonop. Treatment | Overall | Op. Treatment | Nonop. Treatment | Treatment Effect† (95% Confidence Interval) | Op. Treatment | Nonop. Treatment | Treatment Effect† (95% Confidence Interval) | Op. Treatment | Nonop. Treatment | Treatment Effect† (95% Confidence Interval) |
| L2-L3 and L3-L4 | ||||||||||||
| No. of patients | 41 | 53 | 35 | 45 | 36 | 45 | 37 | 42 | ||||
| SF-36 bodily pain‡ | 27.8 (2.7) | 30.1 (2.6) | 29.1 (1.9) | 39.8 (4) | 20.5 (3.5) | 19.3 (8.1, 30.4) | 48.8 (4.2) | 24.3 (3.5) | 24.5 (13, 36) | 49 (4.0) | 24.4 (3.6) | 24.6 (13.2, 36) |
| SF-36 physical functioning‡ | 33.4 (3.4) | 36.3 (3.2) | 35.0 (2.3) | 38.2 (4.1) | 20.6 (3.6) | 17.6 (6.4, 28.9) | 45.7 (4.2) | 21.7 (3.6) | 24 (12.4, 35.7) | 48 (4.1) | 24.6 (3.6) | 23.4 (11.9, 34.9) |
| Oswestry Disability Index‡ | 51.0 (3.0) | 43.5 (2.8) | 46.8 (2.1) | −31.9 (3.1) | −18.3 (2.8) | −13.6 (−22.1, −5.1) | −36.3 (3.2) | −16.6 (2.8) | −19.7 (−28.6, −10.8) | −38.3 (3.1) | −19.3 (2.8) | −19 (−27.7, −10.2) |
| L4-L5 | ||||||||||||
| No. of patients | 300 | 225 | 272 | 165 | 254 | 138 | 254 | 129 | ||||
| SF-36 bodily pain‡ | 21.9 (1) | 32.4 (1.3) | 26.4 (0.9) | 43.7 (1.4) | 25.6 (1.7) | 18.1 (13.9, 22.3) | 44.9 (1.4) | 31.4 (1.8) | 13.6 (9.1, 18) | 43.1 (1.4) | 31.6 (1.9) | 11.6 (7, 16.1) |
| SF-36 physical functioning‡ | 31.2 (1.4) | 46.6 (1.7) | 37.8 (1.1) | 45.1 (1.3) | 25.5 (1.6) | 19.6 (15.7, 23.6) | 46.2 (1.3) | 28.8 (1.7) | 17.4 (13.2, 21.6) | 45.7 (1.3) | 28.6 (1.8) | 17.1 (12.8, 21.4) |
| Oswestry Disability Index‡ | 57.0 (1.2) | 40.6 (1.4) | 50.0 (1) | −38.3 (1.1) | −23.4 (1.4) | −14.9 (−18.1, −11.6) | −39.6 (1.1) | −25 (1.5) | −14.6 (−18.1, −11.1) | −38.5 (1.1) | −24.7 (1.5) | −13.8 (−17.3, −10.3) |
| L5-S1 | ||||||||||||
| No. of patients | 434 | 334 | 393 | 222 | 361 | 191 | 355 | 171 | ||||
| SF-36 bodily pain‡ | 23.1 (0.8) | 30 (1.0) | 26.1 (0.6) | 39.7 (1.2) | 23.4 (1.5) | 16.4 (12.8, 20) | 42 (1.2) | 31.5 (1.6) | 10.6 (6.7, 14.4) | 41.7 (1.2) | 34.6 (1.7) | 7.1 (3.1, 11.1) |
| SF-36 physical functioning‡ | 31.9 (1.1) | 45.6 (1.4) | 37.9 (0.9) | 38.3 (1.1) | 21.5 (1.4) | 16.8 (13.4, 20.2) | 43.7 (1.1) | 29.2 (1.5) | 14.5 (10.9, 18.1) | 42.4 (1.1) | 32.5 (1.6) | 9.9 (6.2, 13.6) |
| Oswestry Disability Index‡ | 55.3 (0.9) | 41.9 (1.1) | 49.5 (0.8) | −34.9 (0.9) | −18.1 (1.2) | −16.8 (−19.6, −14) | −36.5 (0.9) | −23.2 (1.3) | −13.4 (−16.4, −10.4) | −36.2 (0.9) | −26 (1.3) | −10.3 (−13.4, −7.2) |
Adjusted for age, gender, race, marital status, work status, disability compensation status, body mass index, smoking, joint problems, migraine headaches, any neurological deficit, herniation (type and location), baseline score, baseline leg-symptom severity, baseline satisfaction with symptoms, self-rated health trend, center, and insurance.
Treatment effect is defined as the change in the operative group minus the change in the nonoperative group. A moving baseline was used, with the clock reset at the time of surgery for any patient having surgery.
The operative and nonoperative values are given as the mean score with the standard error of the mean in parentheses. Each scale ranged from 0 to 100. SF-36 = Short Form-36.