Table 2.
Study characteristics and selected COP parameters measured on a firm surface
| Study | Condition | Duration (s) | Number of trials | Parameter | Low back pain result (SD) |
Healthy controls result (SD) |
p Value |
|---|---|---|---|---|---|---|---|
| Luoto et al. [20] | Normal stance, EO/F | 25 | 1 | mVel | Male: A: 14 mm/s B: 13 mm/s Female: A: 10 mm/s B: 20 mm/s |
Male: C: 12 mm/s Female: C: 11 mm/s |
>0.05 <0.05 |
| Mientjes and Frank [21] | Normal stance, EO/EC, F/C | Unclear | 3 | mPos RMS (ML) RMS (AP) |
– – – |
– – – |
0.099 0.016 0.031 |
| Kuukkanen and Malkia [22] | Unclear stance, EC/F | 20 (40) | 1 | mVel (AP) mVel (ML) |
17.1 mm/s (3.7) 12.3 mm/s (2.7) |
– – |
– – |
| Hamaoui et al. [23] | Normal stance, EO/F | 20 | 5 | mPos (AP) mPos (ML) |
2.9 mm (0.5) 1.6 mm (0.7) |
1.9 mm (0.8) 1.1 mm (0.6) |
0.002 0.032 |
| Grimstone and Hodges [24] | Normal stance, EO/F | 120 | 1 | Mean displacement | 3.2 mm | 2.4 mm | – |
| Brumagne et al. [25]a | Normal stance, Unclear visual condition/F |
60 | 1 | RMS (AP) | Young: ~8 mm Elderly: ~7.5 mm |
Young: ~5 mm Elderly: ~5 mm |
<0.05 <0.05 |
| Hamaoui et al. [26] | Normal stance, EC/F Narrow stance, EC/F |
20 | 5 | Mean displacement | AP 4.3 mm (1.6) ML 2.0 mm (1.2) AP 5.5 mm (1.5) ML 4.7 mm (1.6) |
AP 2.7 mm (0.9) ML 1.3 mm (0.6) AP 3.0 mm (0.6) ML 3.7 mm (0.9) |
<0.05 >0.05 <0.001 >0.05 |
| Mok et al. [27]b | Normal stance, EC/F | 70 | 1 | mVel | 4.3 mm/s (2.17) | 5.03 mm/s (2.8) | >0.05 |
| Smith et al. [28]a | Normal stance, EC/EO/F | 120 | 1 | Mean displacement | EC: ~2.9 mm | EC: ~2.75 mm | – |
| della Volpe et al. [2] | Normal stance, EO/F | 20 | 3 | mVel (AP) RMS length |
12.18 mm/s (1.2) 0.19 mm (0.01) |
10.32 mm/s (0.6) 0.16 mm (0.01) |
– – |
| Popa et al. [29] | Normal stance, EC/F | 20 | 3 | Mean displacement | 2.85 mm (0.024) | 2.09 mm (0.01) | <0.05 |
| Brumagne et al. [30] | Normal stance, EO/EC, F/C | 60 | 1 | RMS (AP) | EC/F: 8.8 mm EO/F: 8.2 mm EC/C: 7.5 mm EO/C:.7.8 mm |
EC/F: 5.4 mm EO/F: 6.2 mm EC/C: 8.7 mm EO/C: 10.5 mm |
>0.05 >0.05 >0.05 <0.05 |
| Lafond et al. [31]a | Normal stance, EC/F Normal stance, EC/F |
60 1,800 |
1 | mVel (AP) RMS length Area mVel (AP) RMS length Area |
~5 mm/s ~1.3 mm ~8.0 cm² ~13.5 mm/s ~11 mm ~18.5 cm² |
~3 mm/s ~4.3 mm ~4.7 cm² ~17.5 mm/s ~17.5 mm ~25.0 cm² |
<0.05 <0.05 <0.05 >0.05 <0.05 >0.05 |
| Harringe et al. [32] | Normal stance, EC/F | 120 | 2 | RMS Vel Area |
2.2 mm/s (0.59) 7.11 cm² (3.04) |
2.06 mm/s (0.6) 6.92 cm² (3.91) |
>0.05 >0.05 |
| Mann et al. [19]a | Normal stance, EC/F | 30 | 1–3 | SD vel m displ AP m displ ML |
~6.7 mm/s ~7.6 mm ~4.5 mm |
~5 mm/s ~3.3 mm ~1.7 mm |
0.015 <0.001 0.007 |
| Salavati et al. [33] | Normal stance, EC/F | 30 | 3 | SD vel mVel |
AP: 13.0 mm/s ML: 15.2 mm/s 13.7 mm/s (0.35) |
AP: 14.8 mm/s ML: 17.2 mm/s 15.9 mm/s (0.33) |
– – – |
AP anteroposterior, BP bipedal, C compliant surface, displ displacement, EC eyes closed, EO eyes open, F firm surface, m displ mean displacement; ML medial–lateral, mPos mean position, mVel mean velocity, RMS root mean square, SD vel standard deviation of velocity
aThe results presented have been extracted from bar-charts
bThe results from unilateral and bilateral static task conditions were not differentiated