Table 1.
Plantar, Auditory, Nerve Conduction and Reaction Time Metrics. Average reaction times to a plantar touch, a pure tone auditory stimulus, and rightward lateral movement of 4 mm at 100 mm/s2 in diabetic (Peripheral Neuropathy), non-diabetic (Neurologically Intact), and young adults. Metrics given in either average ± standard deviation format or median [25% quartile, 75% quartile] format. All metrics for Semmes-Weinstein Monofilament Threshold, Air Conduction Threshold, and Nerve Conduction Studies have been averaged over both the right and left sides of the body. NCV = Nerve Conduction Velocity
| Group | Peripheral Neuropathy (n = 13) | Neurologically Intact (n = 24) | Young Adults (n = 9) |
| Age (yrs) | 60.6 ± 6.5 | 59.4 ± 8.0 | 22.7 ± 1.2 |
| Tactile Semmes-Weinstein Monofilament Thresholds (N) | |||
| Base Metatarsal | 3.610 [2.473, 4.000] | 3.610 [2.440, 3.610] | 0.07 [0.0200, 0.160] † |
| Big Toe | 3.220 [2.220, 4.080] | 3.610 [2.440, 3.840] | 0.07 [0.0200, 0.160] † |
| Air Conduction Thresholds (dB) | |||
| 1 K Hz | 20.0 [15.0, 22.5] | 15.0 [10.0, 20.0] † | |
| 2 K Hz | 20.0 [15.0, 30.0] | 15.0 [10.0, 22.5] ‡‡ | |
| 4 K Hz | 30.0 [17.5, 55.0] | 25.0 [20.0, 35.0] ‡ | |
| 8 K Hz | 35.0 [22.5, 67.5] ‡ | 35.0 [20.0, 57.5] ‡ | |
| Peak Accel Thresholds (mm/s2) to Platform Lateral Moves | |||
| 1 mm | 122.775 ± 68.964‡ | 108.417 ± 59.050 ‡ | 60.778 ± 51.832‡† |
| 2 mm | 77.407 ± 55.982 ‡† | 42.664 ± 37.754 ‡† | 10.386 ± 3.091† |
| 4 mm | 37.275 ± 30.341 | 18.572 ± 19.143 | 13.458 ± 8.343 |
| 8 mm | 20.297 ± 18.680 | 14.077 ± 8.122 | 14.766 ± 8.012 |
| 16 mm | 18.613 ± 9.790 | 11.258 ± 7.723 | 13.590 ± 9.083 |
| Nerve conduction studies | |||
| Sensory NCV (m/s) – Sural | 41.0 [37.0, 45.0] † | 45.0 [42.0, 47.0] † | |
| Motor NCV(m/s) Peroneal | 42.0 [39.0, 46.0] † | 48.0 [46.0, 49.0] † | |
| Motor NCV(m/s) – Tibial | 40.5 [36.0, 45.0] † | 45.0 [42.25, 48.75] † | |
| M-wave Latency (ms) – Peroneal | 4.7 [4.15, 5.45] | 4.6 [4.075, 5.3] | |
| M-wave Latency (ms) – Tibial | 5.35 [4.4, 7.0] * | 4.8 [4.2, 5.6] * | |
| F-wave Latency (ms) – Peroneal | 52.7 [47.625, 60.950] † | 49.7 [46.6, 52.325] † | |
| F-wave Latency (ms) – Tibial | 58.5 [52.6, 64.7] † | 52.5 [50.450, 55.275]† | |
| Reaction Times (ms) | |||
| Touch (Big Toe) | 353.1 ± 113.6 | 331.5 ± 140.5 | 216.0 ± 64.3 |
| Tone (1 kHz) | 282.6 ± 65.2 | 276.9 ± 105.5 | 218.6 ± 64.3 |
| 4 mm Lateral Platform Movement @ 100 mm/s2 | 777.8 ± 243.0‡† | 623.9 ± 191.4‡† | 431.5 ± 59.1‡† |
†Indicates significant group difference
‡Indicates significant threshold difference
*Indicates a trend to significant threshold difference (0.05 < p < 0.07)