Table 4.
F-wave studies in lower extremity nerves.
| Parameters | SBMA (1) | ALS (2) | Control (3) |
P-value |
||
|---|---|---|---|---|---|---|
| 1 vs. 3 | 2 vs. 3 | 1 vs. 2 | ||||
| Tibial nerve | ||||||
| Min F latency (ms) | 45.06 ± 5.93 | 45.43 ± 3.91 | 44.37 ± 2.98 | 0.815 | 0.160 | 0.305 |
| F persistence (%) | 94.28 ± 14.07 | 95.79 ± 15.65 | 99.92 ± 0.46 | <0.001 | 0.004 | 0.077 |
| Mean Famp (μV) | 411.96 ± 195.71 | 399.49 ± 299.88 | 271.87 ± 91.93 | 0.002 | 0.001 | 0.533 |
| Maximum Famp (μV) | 1054.07 ± 451.62 | 798.97 ± 376.37 | 625.48 ± 172.46 | <0.001 | 0.002 | <0.001 |
| Giant F-waves (%) | 2.49 ± 4.38 | 2.05 ± 11.73 | 0.12 ± 0.14 | <0.001 | 0.003 | <0.001 |
| Frequency of Patients with giant F-waves | 20/32 | 12/37 | 2/30 | <0.001 | 0.010 | 0.013 |
| Peroneal nerve | ||||||
| Min F latency (ms) | 44.25 ± 7.31 | 44.19 ± 6.00 | 43.03 ± 3.44 | 0.624 | 0.159 | 0.672 |
| F persistence (%) | 33.14 ± 23.92 | 52.37 ± 25.98 | 46.93 ± 27.16 | 0.007 | 0.188 | <0.001 |
| Mean Famp (μV) | 398.88 ± 219.74 | 227.46 ± 283.16 | 154.31 ± 91.98 | <0.001 | 0.083 | <0.001 |
| Maximum Famp (μV) | 840.35 ± 494.14 | 470.15 ± 334.20 | 370.21 ± 202.03 | <0.05 | >0.05 | <0.05 |
| Giant F-waves (%) | 20.46 ± 28.66 | 5.47 ± 20.24 | 1.22 ± 7.13 | <0.001 | 0.084 | <0.001 |
| Frequency of Patients with giant F-waves | 22/32 | 10/37 | 3/30 | <0.001 | 0.080 | 0.001 |
ALS, amyotrophic lateral sclerosis; CMAP, compound muscle action potential; Famp, F-wave amplitude; Min F latency, minimum F-wave latency; SBMA, spinobulbar muscular atrophy. Values are mean ± SD. Values with significant differences printed in bold characters. For comparisons of parameters between the SBMA patients, the ALS patients, and the normal controls, Bonferroni adjustment was used and α’ < 0.0167 was considered statistically significant.