Table 3.
Range of movement, lumbo-pelvic rhythm and FRR parameters
| Movement parameter | Details | No LBP (n = 124) |
LBP (n = 140) |
p-value |
|---|---|---|---|---|
| Peak trunk flexion | Trunk flexion angular inclination (T12) | 111o ± 16o | 93o ± 16o |
p < .0001 **β = − 16 (− 20, − 12) |
| Small trunk ROM (10th centile, <93o) | Number (%) of people with small trunk flexion | 11 (10%) | 67 (47.8%) | p < .0001 |
| Prevalence ratio* | – | 5.4 (3.5–7.3) | ||
| Large trunk ROM (90th centile, > 128o) | Number (%) of people with large trunk flexion | 12 (10%) | 4 (3%) | p = .008 |
| Prevalence ratio | – | 0.3 (0.1–0.9) | ||
| Peak lumbar flexion | Lumbar ROM | 52o ± 11o | 46o ± 12o |
p < .0001 β = − 6 (− 9, − 12) |
| Small lumbar ROM (10th centile, <39o) | Number (%) of people with small lumbar flexion | 12 (10%) | 41 (29.3%) | P = .0001 |
| Prevalence ratio | – | 3.0 (1.8–4.7) | ||
| Large lumbar ROM (90th centile, >65o) | Number (%) of people with large lumbar flexion | 13 (10%) | 8 (6%) | NS |
| Prevalence ratio | – | 0.5 (0.2–1.2) | ||
| Peak pelvic flexion | Pelvic flexion angular inclination (S2) | 59o ± 15o | 48o ± 15o |
p < .0001 β = −11 (−14, −7) |
| Small pelvic ROM (10th centile, <42o) | Number (%) of people with small pelvic flexion | 10 (9%) | 48 (34%) | p < .0001 |
| Prevalence ratio | – | 3.9 (2.3–5.8) | ||
| Large pelvic ROM (90th centile, >75o) | Number (%) of people with large pelvic flexion | 13 (10%) | 7 (5%) | NS |
| Prevalence ratio | – | 0.5 (0.2–1.1) | ||
| Lumbo-pelvic co-ordination | Mean Lumbar % contribution | 48 ± 11% | 49 ± 11% | NS β = 1.8 (1, 5) |
| Small Lx contribution (10th centile, < 38%) | Number (%) of people with small lumbar contribution | 13 (10%) | 19 (14%) | NS |
| Prevalence ratio | – | 1.3 (0.7–2.4) | ||
| Large Lx contribution (90th centile, > 63%) | Number (%) of people with large lumbar contribution | 11 (9%) | 18 (13%) | NS |
| Prevalence ratio | – | 1.5 (0.7–2.8) | ||
| FRR | Means units of surface EMG activity | 0.012 ± 0.32 | 0.25 ± 0.32 |
p < .0001 β = 0.24 (0.15, −0.31) |
| Low FRR (10th centile, > 0.033 units of EMG activity) | Number (%) of people with reduced FRR | 13 (9%) | 71 (52%) | p < .0001 |
| Prevalence ratio | – | 4.9 (3.4–6.4) |
* Adjusted prevalence ratio’s considering the effect of age and gender are reported only, as there was minimal difference between unadjusted and adjusted ratios indicating minimal effect of age and gender
**β = the beta coefficient (and 95% confidence intervals) from regression models, which represents the size of the difference between the two groups, adjusted for age and gender