Table 3.
Quantitative sensory testing (QST) and proportion of distal limbs with abnormal sensation to brush, cool and warm stimuli at baseline and 4–6 weeks
| Measure (possible score) | Number | Baseline median (IQ range) | 4–6 weeks median (IQ range) | Median of individual changesa (95 % CI) | P value |
|---|---|---|---|---|---|
| QST | |||||
| Mechanical detection threshold forcec (0.026 to 110 g) | 40 | 1.1 (0.3 to 2.9) | 0.3 (0.1 to 1.1) | −0.2a (−7.9 to 1.7) | 0.016b |
| Mechanical detection threshold NRS (0 to 10) | 40 | 0 (0.0 to 0.0) | 0 (0.0 to 0.0) | 0.0a (−0.3 to 0.0) | 0.131b |
| Mechanical pain threshold forced (0.026 to 110 g) | 40 | 34 (11 to 110) | 110 (17 to 110) | 0.0a (−7.4 to 31.9) | 0.198b |
| Mechanical pain threshold NRS (0 to 10) | 39 | 2 (0 to 4) | 1 (0 to 3) | −0.4 (−1.3 to 0.6) | 0.445 |
| Windup ratio | 40 | 1 (0.0 to 2.0) | 1 (0.0 to1.3) | 0.0a (−2.0 to 0.2) | 0.098b |
| Extent of abnormal receptive field | |||||
| Brush stimulus | |||||
| % of forearm below elbow | 20 | 55 (2 to 73) | 24 (0 to 57) | −16 (−32 to 1) | 0.062 |
| % of lower leg below knee | 19 | 65 (16 to 82) | 39 (16 to 64) | −13 (−26 to 0) | 0.056 |
| Cool (25 °C) stimulus | |||||
| % of forearm below elbow | 19 | 70 (34 to 88) | 37 (9 to 79) | −19 (−37 to −2) | 0.036 |
| % of lower leg below knee | 19 | 67 (48 to 97) | 43 (21 to 79) | −24 (−36 to 12) | 0.001 |
| Warm (40 °C) stimulus | |||||
| % of forearm below elbow | 18 | 72 (50 to 88) | 24 (8 to 79) | −28a (−39 to −11) | 0.004b |
| % of lower leg below knee | 19 | 89 (78 to 93) | 56 (20 to 77) | −25 (−41 to −10) | 0.003 |
NRS Numerical Rating Scale (higher scores indicate worse pain), 95 % CI 95 % confidence interval, IQ range interquartile range
aMedian change (when distribution of variables relating to the change between baseline and 4–6 weeks was not normally distributed)
bException—compared using paired t test when Wilcoxon signed rank test used
cHigher values indicate the skin is more numb
dLower values indicate increased sensitivity to painful stimuli