Table 2 Mean and SD of vertebral displacement (degrees), for asymptomatic subjects, resulting from the PA testing procedure (first row). Values for vertebral displacement above (second row) and below (third row) two standard deviations (2SD) from the mean of asymptomatic subjects are in bold. Number of subjects with vertebral displacement above and below two standard deviations (2SD) from the asymptomatic group mean is listed bellow. Note that 1 subject in the asymptomatic group and 4 in the symptomatic group exhibited vertebral displacement outside of the 2SD range.
Motion-segment | L1 – L2 | L2 – L3 | L3 – L4 | L4 – L5 | L5 – S1 | Number of subjects with at least one level above 2SD or below 2SD (%) |
|---|---|---|---|---|---|---|
Mean (SD) vertebral displacement [degrees] for asymptomatic subjects | 3.7 (1.4) | 3.8 (1.4) | 3.5 (1.7) | 3.2 (1.3) | 3.6 (1.1) | |
+2SD [degrees] | 6.5 | 6.5 | 6.9 | 5.8 | 5.8 | |
Asymptomatic (N = 20) | 1 | 0 | 0 | 0 | 0 | 1 (5%) |
Symptomatic (N = 45) | 4c,d | 2c,d | 2 | 4c | 9 | 18 (40%) |
-2SD [degrees] | 0.9 | 0.9 | 0.0 | 0.9 | 1.3 | |
Asymptomatic (N = 20) | 0 | 1a | 1a | 1 | 0 | 2 (10%) |
Symptomatic (N = 45) | 2b | 0 | 0 | 0 | 2b | 2 (4.4%) |
Chi- square | 10.0 p < 0.01 | 4.18 p < 0.05 |