Background
Methods
Participants
Mean (standard deviation) | |
---|---|
Age (years) | 39.9 (9.9) |
Height (cm) | 168.7 (8.6) |
Body mass (kg) | 77.3 (17.5) |
Body mass index (kg/m2) | 27.2 (0.24) |
Job seniority (years) | 17 (9) |
Back Pain > 3 days in the last 12 months | 19 out of 26 |
Average LBP (NRS 0–10) in the last 7 days | 2.7 (2.4) |
Experimental protocol
Procedure to mark the 14 anatomical locations
Data analysis
Results
Intra-session relative and absolute reliability of PPT in the low back
Trials | T1-T2 | T1-T3 | T2-T3 | T1-T2-T3 | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Points | ICC (95 % CI) | SEM (kPa) | MDC (kPa) | MDC (%) | ICC (95 % CI) | SEM (kPa) | MDC (kPa) | MDC (%) | ICC (95 % CI) | SEM (kPa) | MDC (kPa) | MDC (%) | ICC (95 % CI) | SEM (kPa) | MDC (kPa) | MDC (%) |
P1 | 0.92 (0.84–0.96) | 65.9 | 182.7 | 38.1 | 0.88 (0.77–0.94) | 82.9 | 229.7 | 48.2 | 0.92 (0.84–0.96) | 66.7 | 185.0 | 39.0 | 0.91 (0.84–0.95) | 72.0 | 199.7 | 41.9 |
P2 | 0.95 (0.90–0.98) | 53.5 | 148.4 | 31.2 | 0.91 (0.83–0.96) | 72.1 | 199.8 | 41.1 | 0.94 (0.88–0.97) | 60.1 | 166.5 | 34.2 | 0.94 (0.89–0.97) | 62.2 | 172.4 | 35.7 |
P3 | 0.92 (0.84–0.96) | 72.8 | 201.9 | 42.2 | 0.89 (0.78–0.95) | 86.6 | 240.1 | 48.9 | 0.96 (0.91–0.98) | 54.0 | 149.8 | 31.1 | 0.92 (0.86–0.96) | 72.2 | 200.1 | 41.4 |
P4 | 0.92 (0.83–0.96) | 71.9 | 199.4 | 38.8 | 0.88 (0.77–0.94) | 86.7 | 240.4 | 45.7 | 0.95 (0.89–0.97) | 61.9 | 171.6 | 32.5 | 0.92 (0.85–0.96) | 74.0 | 205.1 | 39.2 |
P5 | 0.91 (0.83–0.96) | 75.6 | 209.4 | 41.5 | 0.86 (0.71–0.93) | 95.2 | 263.8 | 52.3 | 0.93 (0.86–0.97) | 70.4 | 195.1 | 38.4 | 0.90 (0.83–0.95) | 80.8 | 224.0 | 44.3 |
P6 | 0.92 (0.84–0.96) | 67.3 | 186.5 | 35.2 | 0.88 (0.76–0.94) | 81.0 | 224.6 | 41.8 | 0.95 (0.90–0.98) | 53.0 | 147.0 | 26.9 | 0.92 (0.85–0.96) | 67.9 | 188.2 | 35.0 |
P7 | 0.93 (0.85–0.97) | 65.8 | 182.3 | 37.3 | 0.89 (0.78–0.95) | 77.2 | 213.9 | 43.9 | 0.92 (0.83–0.96) | 71.0 | 196.8 | 39.1 | 0.91 (0.85–0.96) | 71.3 | 197.6 | 40.1 |
P8 | 0.90 (0.80–0.95) | 77.5 | 214.7 | 45.1 | 0.89 (0.77–0.95) | 82.6 | 228.9 | 47.7 | 0.95 (0.89–0.97) | 59.4 | 164.7 | 33.2 | 0.91 (0.85–0.96) | 73.7 | 204.2 | 42.2 |
P9 | 0.94 (0.87–0.97) | 65.6 | 181.8 | 35.7 | 0.91 (0.81–0.96) | 74.7 | 207.2 | 39.9 | 0.95 (0.90–0.98) | 57.4 | 159.1 | 30.1 | 0.93 (0.88–0.97) | 66.1 | 183.3 | 35.3 |
P10 | 0.94 (0.87–0.97) | 60.7 | 168.3 | 33.3 | 0.93 (0.86–0.97) | 64.9 | 180.0 | 34.4 | 0.94 (0.87–0.97) | 63.4 | 175.8 | 33.6 | 0.94 (0.89–0.97) | 62.9 | 174.4 | 33.7 |
P11 | 0.94 (0.86–0.97) | 61.8 | 171.2 | 32.5 | 0.94 (0.85–0.97) | 62.2 | 172.3 | 32.7 | 0.92 (0.85–0.96) | 67.8 | 188.0 | 34.4 | 0.93 (0.88–0.97) | 63.8 | 176.9 | 33.2 |
P12 | 0.93 (0.86–0.97) | 62.5 | 173.2 | 33.0 | 0.91 (0.82–0.96) | 75.1 | 208.0 | 40.1 | 0.90 (0.80–0.95) | 77.7 | 215.5 | 40.3 | 0.92 (0.85–0.96) | 71.9 | 199.2 | 37.9 |
P13 | 0.95 (0.89–0.98) | 55.6 | 154.1 | 29.4 | 0.94 (0.87–0.97) | 58.6 | 162.4 | 30.4 | 0.93 (0.85–0.97) | 66.0 | 183.1 | 33.8 | 0.94 (0.89–0.97) | 60.1 | 166.5 | 31.2 |
P14 | 0.94 (0.88–0.97) | 59.2 | 164.0 | 32.7 | 0.93 (0.80–0.97) | 65.0 | 180.2 | 35.2 | 0.95 (0.90–0.98) | 51.1 | 141.7 | 27.0 | 0.94 (0.89–0.97) | 58.6 | 162.4 | 31.7 |
Pleft
| 0.97 (0.94–0.99) | 38.3 | 106.3 | 21.3 | 0.95 (0.90–0.98) | 50.6 | 140.3 | 27.8 | 0.99 (0.97–0.99) | 27.8 | 77.0 | 15.0 | 0.97 (0.95–0.99) | 39.9 | 110.6 | 21.9 |
Pright
| 0.97 (0.94–0.99) | 42.2 | 117.0 | 23.1 | 0.95 (0.89–0.98) | 51.8 | 143.7 | 28.1 | 0.98 (0.95–0.95) | 37.5 | 103.8 | 19.9 | 0.97 (0.94–0.98) | 44.1 | 122.3 | 23.8 |
Pall
| 0.98 (0.95–0.99) | 36.7 | 101.8 | 20.2 | 0.95 (0.90–0.98) | 50.0 | 138.7 | 27.3 | 0.99 (0.97–0.99) | 28.3 | 78.5 | 15.2 | 0.97 (0.95–0.99) | 39.3 | 108.9 | 21.4 |
T1-T2 | T1-T3 | T2-T3 | T1-T2-T3 | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
ICC (95 % CI) | SEM (kPa) | MDC (kPa) | MDC (%) | ICC (95 % CI) | SEM (kPa) | MDC (kPa) | MDC (%) | ICC (95 % CI) | SEM (kPa) | MDC (kPa) | MDC (%) | ICC (95 % CI) | SEM (kPa) | MDC (kPa) | MDC (%) | |
Men | 0.98 (0.93–0.99) | 35.8 | 99.2 | 17.3 | 0.95 (0.87–0.98) | 50.1 | 138.9 | 24.1 | 0.98 (0.95–0.99) | 30.6 | 84.9 | 14.5 | 0.97 (0.93–0.99) | 39.5 | 109.5 | 18.9 |
Women | 0.97 (0.91–0.99) | 36.8 | 102.1 | 25.0 | 0.95 (0.86–0.98) | 49.1 | 136.1 | 32.7 | 0.99 (0.97–1.00) | 24.0 | 66.5 | 15.8 | 0.97 (0.93–0.99) | 37.8 | 104.8 | 25.3 |
Age ≤ 41 | 0.97 (0.92–0.99) | 36.4 | 101.0 | 20.3 | 0.96 (0.87–0.98) | 47.7 | 132.3 | 26.3 | 0.99 (0.96–1.00) | 23.4 | 65.0 | 13.2 | 0.97 (0.94–0.99) | 37.0 | 102.5 | 20.5 |
Age > 41 | 0.98 (0.91–0.99) | 35.9 | 99.5 | 19.8 | 0.96 (0.94–0.99) | 51.8 | 143.6 | 28.3 | 0.98 (0.95–0.99) | 32.0 | 88.7 | 17.0 | 0.97 (0.93–0.99) | 40.6 | 112.5 | 22.1 |
BMI ≤ 25 | 0.95 (0.86–0.98) | 42.7 | 118.3 | 25.0 | 0.91 (0.75–0.97) | 56.2 | 155.7 | 32.6 | 0.97 (0.91–0.99) | 34.5 | 95.6 | 19.9 | 0.95 (0.87–0.98) | 45.1 | 124.9 | 26.2 |
BMI > 25 | 0.98 (0.96–1.00) | 28.9 | 80.0 | 15.3 | 0.97 (0.91–0.99) | 43.0 | 119.2 | 22.5 | 0.99 (0.98–0.99) | 19.9 | 55.2 | 10.2 | 0.99 (0.96–1.00) | 31.9 | 88.3 | 16.6 |
Pain ≤ 2.5 | 0.97 (0.87–0.99) | 37.9 | 105.0 | 17.8 | 0.93 (0.79–0.97) | 57.9 | 160.4 | 26.9 | 0.98 (0.88–0.99) | 35.2 | 97.6 | 16.0 | 0.96 (0.90–0.99) | 44.6 | 123.6 | 20.7 |
Pain > 2.5 | 0.97 (0.92–0.99) | 34.5 | 95.6 | 23.0 | 0.96 (0.89–0.99) | 40.5 | 112.4 | 26.6 | 0.99 (0.97–1.00) | 18.7 | 51.7 | 12.4 | 0.97 (0.94–0.99) | 32.4 | 89.7 | 21.4 |
Number of trials to ensure reliable measurements
Trial 1 | Trial 2 | Trial 3 | T1-T2-T3 | T1−T2 | T1−T3 | T2−T3 | |||||
---|---|---|---|---|---|---|---|---|---|---|---|
Mean | (SD) | Mean | (SD) | Mean | (SD) | Mean | (SD) |
p-value |
p-value |
p-value | |
P1 | 480.9 | (242.6) | 478.3 | (237.4) | 471.7 | (245.0) | 477.0 | (238.8) | 0.9991 | 0.9888 | 0.9942 |
P2 | 475.1 | (241.4) | 476.8 | (246.4) | 497.8 | (255.9) | 483.2 | (245.2) | 0.9997 | 0.9377 | 0.9462 |
P3 | 487.8 | (263.4) | 468.7 | (259.5) | 495.0 | (264.7) | 483.8 | (259.6) | 0.9598 | 0.9942 | 0.9253 |
P4 | 511.6 | (236.4) | 515.4 | (269.6) | 541.3 | (273.1) | 522.8 | (257.4) | 0.9984 | 0.9046 | 0.9265 |
P5 | 501.0 | (241.9) | 509.2 | (276.3) | 507.4 | (262.6) | 505.9 | (257.5) | 0.9923 | 0.9953 | 0.9996 |
P6 | 521.5 | (228.1) | 537.5 | (247.5) | 554.5 | (240.2) | 537.8 | (236.2) | 0.9661 | 0.8635 | 0.9616 |
P7 | 473.6 | (231.4) | 504.8 | (264.0) | 501.3 | (238.7) | 493.2 | (242.5) | 0.8828 | 0.9064 | 0.9984 |
P8 | 459.5 | (236.5) | 492.5 | (261.2) | 499.6 | (259.5) | 483.9 | (250.2) | 0.8766 | 0.8240 | 0.9940 |
P9 | 499.4 | (250.0) | 520.3 | (273.7) | 538.4 | (250.6) | 519.3 | (255.7) | 0.9505 | 0.8391 | 0.9631 |
P10 | 506.1 | (244.0) | 505.9 | (252.1) | 539.2 | (260.4) | 517.1 | (249.7) | 1.0000 | 0.8758 | 0.8745 |
P11 | 507.4 | (255.2) | 547.5 | (253.3) | 545.7 | (244.2) | 533.5 | (248.6) | 0.8213 | 0.8357 | 0.9996 |
P12 | 508.0 | (246.2) | 540.8 | (242.6) | 528.8 | (258.8) | 525.9 | (246.6) | 0.8750 | 0.9476 | 0.9823 |
P13 | 516.0 | (245.4) | 533.2 | (246.6) | 551.2 | (249.0) | 533.5 | (244.5) | 0.9632 | 0.8554 | 0.9600 |
P14 | 488.2 | (244.8) | 513.7 | (249.4) | 535.6 | (233.5) | 512.5 | (240.5) | 0.9184 | 0.7457 | 0.9390 |
Pleft
| 493.1 | (232.2) | 505.3 | (241.0) | 517.8 | (242.7) | 505.4 | (236.0) | 0.9800 | 0.9212 | 0.9793 |
Pright
| 497.7 | (235.2) | 515.3 | (254.5) | 526.1 | (244.2) | 513.1 | (242.1) | 0.9609 | 0.9013 | 0.9850 |
Pall
| 495.4 | (232.7) | 510.3 | (246.2) | 522.0 | (242.2) | 509.2 | (237.8) | 0.9708 | 0.9105 | 0.9821 |
Trial 1 | Trial 2 | Trial 3 | T1-T2-T3 | T1−T2 | T1−T3 | T2−T3 | |||||
---|---|---|---|---|---|---|---|---|---|---|---|
Mean | (SD) | Mean | (SD) | Mean | (SD) | Mean | (SD) |
p-value |
p-value |
p-value | |
Males | 565.6* | 230.0 | 580.7 | 238.2 | 587.3 | 231.9 | 587.3 | 231.9 | 0.9817 | 0.9627 | 0.9965 |
Females | 403.3 | 201.1 | 413.7 | 223.8 | 428.1 | 228.3 | 415.0 | 212.5 | 0.9919 | 0.9547 | 0.9844 |
Age ≤ 41 | 498.6 | 227.7 | 495.8 | 231.5 | 506.0 | 230.7 | 500.1 | 224.7 | 0.9994 | 0.9957 | 0.9919 |
Age > 41 | 486.7 | 238.7 | 516.6 | 262.9 | 526.6 | 258.1 | 510.0 | 247.8 | 0.9479 | 0.9092 | 0.9940 |
BMI ≤ 25 | 470.6 | 197.9 | 474.2 | 204.9 | 484.0 | 187.9 | 476.3 | 192.3 | 0.9987 | 0.9823 | 0.9906 |
BMI > 25 | 513.7 | 259.7 | 535.3 | 277.7 | 545.8 | 283.7 | 531.6 | 267.9 | 0.9744 | 0.9449 | 0.9940 |
Pain ≤ 2.5 | 572.7 | 230.5 | 606.0* | 237.0 | 613.4* | 227.3 | 597.4* | 226.6 | 0.9236 | 0.8884 | 0.9961 |
Pain > 2.5 | 418.3 | 207.7 | 412.4 | 215.6 | 425.0 | 221.2 | 418.6 | 210.0 | 0.9968 | 0.9960 | 0.9858 |
Trial 1−Trial 2 | Trial 1−Trial 3 | Trial 2−Trial 3 | |
---|---|---|---|
Mean PPT difference (95 % CI) | Mean PPT difference (95 % CI) | Mean PPT difference (95 % CI) | |
P1 | 2.6 (0.6 to 4.6) | 9.2 (8.3 to 10.1) | 6.6 (3.7 to 9.5) |
P2 | −1.6 (−3.6 to 0.3) | −22.6 (−28.2 to −17.1) | −21.0 (−24.6 to −17.4) |
P3 | 19.1 (17.7 to 20.6) | −7.2 (−7.7 to −6.7) | −26.4 (−28.3 to −24.4) |
P4 | −3.8 (−16.4 to 8.8) | −29.7 (−43.7 to −15.7) | −25.9 (−27.3 to −24.5) |
P5 | −8.3 (−21.4 to 4.9) | −6.4 (−14.3 to 1.4) | 1.8 (−3.4 to 7.1) |
P6 | −16.0 (−23.4 to −8.6) | −33.0 (−37.6 to −28.3) | −17.0 (−19.8 to −14.2) |
P7 | −31.2 (−43.6 to −18.8) | −27.7 (−30.5 to −24.9) | 3.5 (−6.1 to 13.1) |
P8 | −33.0 (−42.5 to −23.6) | −40.1 (−48.8 to - 31.3) | −7.0 (−7.7 to −6.4) |
P9 | −21.0 (−30.0 to −11.9) | −39.0 (−39.2 to −38.8) | −18.0 (−26.9 to −9.2) |
P10 | 0.2 (−2.9 to 3.3) | −33.1 (−39.4 to −26.9) | −33.3 (−36.5 to −30.1) |
P11 | −40.1 (−40.9 to −39.4) | −38.3 (−42.5 to −34.1) | 1.8 (−1.6 to 5.3) |
P12 | −32.8 (−34.2 to −31.5) | −20.8 (−25.6 to −16.0) | 12.0 (5.8 to 18.2) |
P13 | −17.2 (−17.7 to 16.8) | −35.2 (−36.5 to −33.8) | −18.0 (−18.9 to −17.0) |
P14 | −25.5 (−27.3 to −23.7) | −47.4 (−36.5 to −33.8) | −21.9 (−28.0 to −15.9) |
Pleft
| −12.2 (−15.5 to −8.9) | −24.6 (−28.6 to −20.6) | −12.4 (−13.1 to −11.8) |
Pright
| −17.6 (−24.9 to −10.3) | −28.4 (−31.9 to −25.0) | −10.8 (−14.7 to −6.9) |
Pall
| −14.9 (−20.0 to −9.8) | −26.5 (−30.2 to −22.9) | −11.6 (−13.1 to −10.1) |