PNS therapy | Placebo† | |||
Full analysis | Per protocol | Full analysis | Per protocol | |
Average RLP, mean (SD, n) | ||||
Baseline score: diary average‡ | 6.4 (1.0, 7) | 6.4 (1.2, 5) | 6.4 (1.3, 11) | 6.5 (1.4, 10) |
Baseline score: BPI-5‡ | 6.3 (1.0, 7) | 6.4 (0.9, 5) | 5.9 (1.8, 11) | 6.0 (1.8, 10) |
Average RLP: reduction from baseline, mean (SD, n), % | ||||
Weeks 1–4 | 33 (43, 7) | 48 (43, 5) | 25 (22, 11) | 28 (22, 10) |
Weeks 5–8 | 36 (32, 7) | 48 (29, 5) | 27 (28, 11) | 30 (28, 10) |
Month 3 | 64 (24, 5)* | 64 (24, 5)* | 33 (43, 8) | 18 (43, 8) |
Month 4 | 86 (16, 4)** | 86 (16, 4)** | 16 (49, 7) | 16 (49, 7) |
Month 5 | 61 (30, 5)* | 61 (30, 5)* | 31 (40, 6) | 31 (40, 6) |
Month 6 | 37 (29, 4) | 37 (29, 4) | −3 (28, 6) | −3 (28, 6) |
Month 7 | 62 (30, 4) | 62 (30, 4) | 0 (20, 5) | 0 (20, 5) |
Month 8 | 86 (20, 2) | 86 (20, 2) | 2 (17, 4) | 2 (17, 4) |
Month 9 | 93 (10, 2) | 93 (10, 2) | −17 (17, 3) | −17 (17, 3) |
Month 10 | 93 (10, 2) | 93 (10, 2) | −6 (10, 3) | −6 (10, 3) |
Month 11 | 93 (10, 2) | 93 (10, 2) | −8 (12, 2) | −8 (12, 2) |
Month 12 | 86 (0, 1) | 86 (0, 1) | 0 (0, 2) | 0 (0, 2) |
Average PLP, mean (SD, n) | ||||
Baseline score: diary average‡ | 6.9 (1.7, 11) | 6.6 (1.5, 10) | 6.8 (1.7, 13) | 6.8 (1.7, 13) |
Baseline score: BPI-5‡ | 6.4 (1.2, 11) | 6.4 (1.3, 10) | 6.5 (2.0, 13) | 6.5 (2.0, 13) |
Average PLP: reduction from baseline, mean (SD, n), % | ||||
Weeks 1–4 | 51 (24, 11) | 56 (19, 10)* | 23 (24, 13) | 23 (24, 13) |
Weeks 5–8 | 56 (33, 11)* | 62 (28, 10)** | 33 (28, 13)* | 33 (28, 13)* |
Month 3 | 58 (36, 10)* | 58 (36, 10)* | 23 (29, 10) | 23 (29, 10) |
Month 4 | 66 (31, 8)** | 66 (31, 8)** | 29 (21, 8)* | 29 (21, 8)* |
Month 5 | 55 (36, 9) | 55 (36, 9) | 28 (21, 7) | 28 (21, 7) |
Month 6 | 41 (36, 8) | 41 (36, 8) | 9 (24, 7) | 9 (24, 7) |
Month 7 | 63 (32, 8) | 63 (32, 6) | 5 (35, 5) | 5 (35, 5) |
Month 8 | 61 (40, 6) | 61 (40, 6) | −5 (26, 4) | −5 (26, 4) |
Month 9 | 61 (40, 6) | 61 (40, 6) | −2 (31, 3) | −2 (31, 3) |
Month 10 | 66 (39, 5) | 66 (39, 5) | 3 (38, 3) | 3 (38, 3) |
Month 11 | 66 (39, 5) | 66 (39, 5) | −17 (24, 2) | −17 (24, 2) |
Month 12 | 55 (48, 5) | 55 (48, 5) | 14 (20, 2) | 14 (20, 2) |
Follow-up is ongoing; data are as observed in months 7–12.
*P<0.05, **p<0.01, vs placebo group at the end of the placebo period.
†Placebo group received active stimulation during weeks 5–8.
‡Measured by daily pain diaries during weeks 1–8, then by BPI-SF during follow-up.
BPI-SF, Brief Pain Inventory Short Form; PLP, phantom limb pain; PNS, peripheral nerve stimulation; RLP, residual limb pain.