Manniche 1993b.
| Methods | Randomised by drawing of envelopes | |
| Participants | 62 patients (30 men, 32 women) with chronic low back pain occurring 14 to 60 months after first‐time discectomy for lumbar disc protrusion; participants' self reported global assessment of operation outcome was "good", "fair" or "unchanged". Interventions start 14 to 60 months post‐surgery | |
| Interventions | (I) (N = 31) Intensive dynamic exercise with hyperextension, start session with hot pack (optional) (20 minutes), followed by (1) trunk lifting, (2) leg lifting: one and two with greatest possible extension, (3) abdominal exercise (all in series of 10; one minute rest in between), (4) pull to neck (50 times). Two sessions a week (one session: 60 to 90 minutes), total of 24 sessions in three months. (C) (N = 31) exactly the same procedure, but in the 1st and 2nd exercise, the movement range of the back and hip is only from 90 degrees flexion to 0 degrees. No hyperextension allowed. | |
| Outcomes | Overall improvement post‐treatment, 3 months and one year (at one year) (I) 38%, (C) 61% scored "very satisfactory" or "satisfactory, little discomfort" not statistically significant. Improvement functional status (low back pain rating scale 0 to 130) post‐treatment, 3, 12 months (Median 10th to 90th percentile): (I) 10 (0 to 31), 8 (‐15 to 28), 3 (‐11 to 23), (C) 7 (‐13 to 22), 1 (‐14 to 9), 0 (‐26 to 9), statistically significant at 3 months only. Post‐treatment, both groups significantly improved | |
| Notes | ||
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | Randomised by drawing envelopes |
| Allocation concealment (selection bias) | Low risk | Personal communication |
| Blinding (performance bias and detection bias) All outcomes ‐ patients? | High risk | With versus without hyperextension |
| Blinding (performance bias and detection bias) All outcomes ‐ care providers? | High risk | With versus without hyperextension |
| Blinding (performance bias and detection bias) All outcomes ‐ outcome assessors? | High risk | Patient reported |
| Incomplete outcome data (attrition bias) All outcomes ‐ drop‐outs? | High risk | 5/31 = 16%, 10/31 = 32% |
| Incomplete outcome data (attrition bias) All outcomes ‐ ITT analysis? | High risk | Dropouts |
| Selective reporting (reporting bias) | Low risk | Pain and function in methods, reported in Table 4 |
| Similarity of baseline characteristics? | Low risk | Tables 3, 4 |
| Co‐interventions avoided or similar? | Low risk | Personal communication: no problems with compliance observed |
| Compliance acceptable? | Low risk | 47 = 76% completed intervention, results |
| Timing outcome assessments similar? | Low risk | Three, 12 months |