Article Figures & Data
Tables
- Table 1
The characteristics of the study participants are identical to that listed in the recently published article for the motor NCS reference data.13
Upper limb study (n= 127) Lower limb study (n = 137) Age (years) Mean ± SD 31.9±10.4 33.7±11.1 Range 20–65 20–66 20–29 64 60 30–39 31 36 40–49 25 28 50–59 5 10 ≥ 60 2 3 Sex, n (%) Male 40 (31.5) 46 (33.6) Female 87 (68.5) 91 (66.4) Height (cm) Mean±SD 163.4±9.1 163±9.4 Range 131±189 131-189 Weight (kg) Mean–SD 72.0±15.8 74.3±17.9 Range 37–130 37-130 BMI Mean±SD 26.9±5.4 27.9±6.2 Range 15–50.8 15–50.8 Nerve N Absent Amplitude (µV) Peak latency (ms) Conduction velocity (m/s) Median sensory D2 118 0 61.6±20.3 (23–130) 3.0±0.23 (2.6–3.5) 62.0±4.9 (52–71) Median sensory D4 109 0 32.6±11.3 (10–62) 3.1±0.25 (2.5–3.7) 59.5±5.4 (50–74) Ulnar sensory D4 109 0 14.7±34.1 (2.0–92) 3.0±0.24 (2.4–3.6) 62.1±5.0 (52–74) Ulnar sensory D5 118 0 53.0±17.9 (18–108) 3.0±0.26 (2.5–3.7) 61±5 (50–74) Median mixed palmar 100 0 — 1.8±0.16 (1.4–2.1) — Ulnar mixed palmar 100 0 — 1.7±0.14 (1.3–2.1) — Radial sensory 111 0 49.2±12.9 (24–91) 2.1±0.21 (1.6–2.7) 67.6±7.6 (50–91) Medial antebrachial sensory cutaneous 71 0 14.1±7.0 (4–42) 2.1±0.23 (1.7–2.8) 62.8±8.8 (48–94) Lateral antebrachial sensory cutaneous 71 0 19.7±8.9 (4–44) 2.1±0.17 (1.4–2.5) 65±7.4 (49–83) Sural 134 0 18.2±7.7 (4.0–53) 3.5±0.3 (2.5–4.5) 51.9±5.7 (40–70) Superficial fibular 134 8 (6%) 15.7±8.6 (0.01–55) 3.3±0.3 (2.5–4.2) 56.9±6.3 (44–78) D2 - index finger
D4 - ring finger
D5 - little finger
Nerve N Age Amplitude (µV) Peak latency (ms)‡ Conduction velocity (m/s) 3rd percentile (LLN)† 97th percentile (ULN) 3rd percentile (LLN)† Median sensory D2 118 20 31 (24) 3.5 (3.5) 52 (52) 40 27 (18) 60 22 (13) β0* 3.613 (3.444) β1* − 0.008 (−0.014) Ulnar sensory D5 118 20 36 (24) 3.5 (3.7) 51 (50) 40 21 (12) 60 12 (6) β0* 4.124 (3.853) β1* −0.027 (−0.034) Median D2-(minus) ulnar D5 PL difference 118 20–65 — 0.4 (0.4) — Median-(minus) ulnar D4 PL difference 109 20–65 — 0.4 (0.5) — Median-(minus) ulnar mixed palmar PL difference 100 20–65 — 0.3 (0.4) — Superficial radial sensory 111 20 29 (24) 2.6 (2.7) 53 (50) 40 25 (20) 60 22 (16) β0* 3.493 (3.378)† β1** −0.007 (−0.01)† Medial antebrachialcutaneous 71 20 - 65 4 (4)§ 2.7 (2.8) 49 (48) Lateral antebrachialcutaneous 71 20 - 65 8 (4)§ 2.5 (2.5) 51 (49) Sural 134 20 9 (4) 4.3 (4.5) 41 (40) 40 6 (2) 60 4 (1) β0* 2.678 (2.223)† β1* −0.023 (−0.037)† Superficial fibular 126¥ 20 10 (5) 3.9 (4.2) 48 (44) 40 7 (3) 60 5 (1) β0* 2.629 (2.186)† β1* −0.018 (−0.029)† Data are combined for NCS parameters with no age effect. ↵* Regressioncoefficients obtained from the quantile regression model: log (predicted value) = β0 + β1 (age).
↵† LLN - the lower limit of the 95% confidence interval at minimum values in the sample.
↵‡ ULN - represents the upper limit of the 95% confidence interval at maximum values in the sample.
↵§ Reference values for the median and the lateral antebrachialcutaneous nerves were calculated at the 5th percentile due to the small sample size.
↵¥ Eight out of 134 participants had unrecordable superficial fibular sensory amplitudes. Those were excluded from the analysis as recommended by the NDTF.
PL - Peak latency
D2 - index finger
D4 - ring finger
D5 - little finger
M2snap-p U5snap-p Rsnap_-p Medant-spLatant-sp age sex M2snap_amp 1.0000 U5snap_amp 0.7292 1.0000 Rsnap_amp 0.4067 0.3815 1.0000 Medante_amp −0.0397 −0.0003 0.0217 1.0000 Latante_amp 0.0650 0.0679 0.2508 0.1842 1.0000 age −0.4977 −0.4206 −0.1432 −0.1571 0.0366 1.0000 sex −0.3120 −0.3421 −0.4096 −0.0323 0.1882 0.1466 1.0000 Ht −0.2194 −0.2389 −0.3767 −0.0609 0.0907 −0.1159 0.6716 Wt −0.3760 −0.3890 −0.2355 −0.3091 0.1272 0.3166 0.4925 BMI −0.3110 −0.3018 −0.0433 −0.3748 0.0903 0.4155 0.1592 BMI −0.3110 −0.3018 −0.0433 −0.3748 0.0903 0.4155 0.1592 M2snap-t U5snap-t Rsnap_-t MedanI-tLaIanI-t sex age M2snap_lat 1.0000 U5snap_lat 0.6906 1.0000 Rsnap_lat 0.5139 0.5091 1.0000 Medante_lat 0.0154 0.2244 0.1906 1.0000 Latante_lat 0.3596 0.2842 0.0535 0.0376 1.0000 sex 0.0499 0.1707 0.1037 0.1309 0.0120 1.0000 age 0.3250 0.1161 0.1062 0.0536 −0.0012 0.1466 1.0000 Ht 0.0181 0.1991 0.1731 0.2239 0.0248 0.6716 −0.1159 BMI 0.1064 0.0075 −0.0627 0.2253 −0.1356 0.1592 0.4155 BMI 0.1064 0.0075 −0.0627 0.2253 −0.1356 0.1592 0.4155 Sural_-p surat_~k SupP_AmpSupP_P~k age sex Ht Sural_Amp 1.0000 surat_Peak −0.0904 1.0000 SupP_Amp 0.4186 −0.0394 1.0000 SupP_Peak −0.2803 0.4293 −0.2692 1.0000 age −0.2698 0.0261 −0.3332 0.2546 1.0000 sex −0.0655 0.1064 −0.0826 0.2344 0.0892 1.0000 Ht −0.1640 0.2387 −0.0632 0.3278 −0.2076 0.6223 1.0000 Wt −0.3297 0.0249 −0.3629 0.2532 0.3015 0.3971 0.3934 BMIBMI −0.2875 −0.0767 −0.3905 0.1211 0.4420 0.1009 −0.1078 −0.2875 −0.0767 −0.3905 0.1211 0.4420 0.1009 −0.1078 1. Median SNAP amplitude
M2_snap_log Coef. Std. Err. t P>|t| [959 Conf. Interval] age −.0226158 .003348 −6.76 0.000 −.0292487 −.0159829 BMI −.0175226 .0105759 −1.66 0.100 −.0384753 .0034301 Ht .0056459 .0139544 0.40 0.687 −.0220003 .0332921 sex −.135719 .1011429 −1.34 0.182 −.3361014 .0646634 cons 3.730818 2.196502 1.70 0.092 −.6208482 8.082485 M2_snap_log Coef. Std. Err. t P>|t| [95% Conf. Interval.] age −.0083333 .0029359 −2.84 0.005 −.0141482 −.0025184 _cons 3.613334 .0855324 42.25 0.000 3.443926 3.782741 2-Ulnar SNAP amplitudes
Usnap_log Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.0244541 .0028474 −8.59 0.000 −.0300948 −.0188135 BMI −.0257745 .0041519 −6.21 0.000 −.0339993 −.0175496 Ht −.0138853 .0018977 −7.32 0.000 −.0176447 −.0101259 sex .2340236 .0616957 3.79 0.000 .111805 .3562423 _cons 6.971722 .3444768 20.24 0.000 6.289316 7.654128 Usnap_log Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.0268421 .0036165 −7.42 0.000 −.0340044 −.0196798 _cons 4.124737 .137247 30.05 0.080 3.852926 4.396548 3-Superficial radial SNAP amplitude
Rsnap_log Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.000749 .0035756 −0.21 0.834 −.0078379 .0063399 BMI .0019485 .0027657 0.70 0.483 −.0035347 .0074318 Ht −.0093068 .0021753 −4.28 0.000 −.0136196 −.004994 sex −.1561534 .0325046 −4.80 0.000 −.220597 −.0917099 _cons 4.978477 .3481969 14.30 0.000 4.288143 5.668812 Rsnap_log Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.0068182 .0015801 −4.32 0.000 −.0099498 −.0036865 _cons 3.493636 .0582263 60.00 0.000 3.378234 3.609039 1. Median antebrachial SNAP amplitude
Mante_log Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.0005159 .0141204 −0.04 0.971 −.0287082 .0276764 BMI −.0334374 .0260603 −1.28 0.204 −.0854686 .0185937 Ht .0197315 .0256201 0.77 0.444 −.0314208 .0708838 sex .28859 .6344127 0.45 0.651 −.9780558 1.555236 _cons −.525155 3.940147 −0.13 0.894 −8.391913 7.341603 1-Lateral antebrachial SNAP amplitude.
Lante_log Coef. Std. Err. t P>|t| [95%Conf. Interval] age .0070564 .0097405 0.72 0.471 −.0123912 .026504 BMI −.0048636 .0183935 −0.26 0.792 −.0415874 .0318603 Ht .0191673 .0192922 0.99 0.324 −.0193509 .0576854 sex −.1087629 .4096582 −0.27 0.791 −.9266719 .709146 _cons −1.004466 2.952763 −0.34 0.735 −6.899847 4.890915 2-Sural amplitude
sural_log Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.0113835 .0045237 −2.52 0.013 −.0203337 −.0024333 BMI −.0183425 .0076491 −2.40 0.018 −.0334763 −.0032086 sex −.154742 .1177951 −1.31 0.191 −.3878025 .0783184 Ht −.0043393 .0054096 −0.80 0.424 −.0150422 .0063637 _cons 3.593453 1.151149 3.12 0.002 1.315876 5.87103 sural_log Coef. SId. Err. t P>|t| [95% Conf. Interval] age −.0147019 .0038068 −3.86 0.000 −.0222326 −.0071712 BMI −.01478 .0221214 −0.67 0.505 −.0585415 .0289814 _cons 2.850454 .5890914 4.84 0.000 1.685091 4.015818 sural_log Coef. 5.d.Err. t P>|t| [95% Conf. Interval] age −.0227778 .0070709 −3.22 0.002 −.0367648 −.0087908 _cons 2.678333 .2298178 11.65 0.000 2.223731 3.132936 3-Superficial fibularamplitude
.qreg supP_log age, quantile (3)
Iteration 1: WLS sum of weighted deviations = 29.298231
Iteration 1: sum of abs. weighted deviations = 34.19511
Iteration 2: sum of abs. weighted deviations = 16.343988 Iteration 3: sum of abs. weighted deviations = 7.5662585 Iteration 4: sum of abs. weighted deviations = 6.7079784 Iteration 5: sum of abs. weighted deviations = 6.6780002
.03 Quantile regression Raw sum of deviations Min sum of deviations 8.141 (about1.79) 6.678 Number of obs = 126Pseudo R2= 0.1797 supP_log Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.0178788 .0058591 −3.05 0.003 −.0294755 −.0062821 _cons 2.629091 .2240852 11.73 0.000 2.185563 3.072618 4-Conduction velocity (97rd percentile unless otherwise indicated) Median
M2snap_cv Coef. Std. Err. t P>|t| [95% Conf. Interval] age 0 .0022617 0.00 1.000 −.0044812 .0044812 sex 0 .0657444 0.00 1.000 −.1302641 .1302641 BMI 0 .0048518 0.00 1.000 −.0096132 .0096132 Ht 0 .0035005 0.00 1.000 −.0069357 .0069357 _cons 52 .5969065 87.12 0.000 50.81731 53.18269 M2snap_cv Coef. Std. Err. t P>|t| [95% Conf. Interval] age 0 .0098232 0.00 1.000 −.0194578 .0194578 _cons 52 .3269304 159.06 0.000 51.35241 52.64759 95th percentile
M2snap_cv Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.0511092 .0966613 −0.53 0.598 −.2426312 .1404128 sex −1.843168 2.071921 −0.89 0.376 −5.948413 2.262078 BMI −.2452919 .1614079 −1.52 0.131 −.5651008 .0745171 Ht .0072057 .1325654 0.05 0.957 −.2554557 .2698672 _cons 61.28131 22.35548 2.74 0.007 16.98678 105.5758 M2snap_cv Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.0909091 .0599642 −1.52 0.132 −.2096866 .0278685 _cons 56.81818 1.950963 29.12 0.000 52.9537 60.68266 5-Ulnar
U5snap_cv Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.2386299 .0148324 −16.09 0.000 −.2680184 −.2092413 sex −1.047073 1.124887 −0.93 0.354 −3.275893 1.181746 BMI .2215983 .0217025 10.21 0.000 .1785976 .264599 Ht −.0506651 .0176017 −2.88 0.005 −.0855407 −.0157895 _cons 62.50312 2.981172 20.97 0.000 56.59631 68.40993 U5snap_cv Coef. Std.Err. t P>|t| [95% Conf. Interval] age −.2 .037503 −5.33 0.000 −.2742862 −.1257138 _cons 58.2 1.4810e5 39.30 0.000 55.26641 61.13359 6-Superficial radial
Rsnap_cv Coef. Std.Err. t P>|t| [95% Conf. Interval] age −.0001111 .0171423 −0.01 0.995 −.0340973 .0338751 BMI .1929142 .0502046 3.84 0.000 .0933788 .2924497 Ht −.4519257 .0978202 −4.62 0.000 −.6458637 −.2579877 sex 5.298252 .4251608 12.46 0.000 4.455329 6.141174 _cons 121.4385 17.03552 7.13 0.000 87.66393 155.2131 7-Sural
Sural_cv Coef. Std.Err. t P>|t| [95% Conf. Interval] age −.0384616 .0630254 −0.61 0.543 −.163132 .0862089 _cons 42.19231 2.875846 14.67 0.000 36.5036 47.88102 8-Superficial fibular
SupP_CV Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.2489812 .015982 −15.58 0.000 −.2806218 −.2173407 BM I −.0351896 .0233381 −1.51 0.134 −.0813936 .0110144 sex 5.56312 .7867994 7.07 0.000 4.005443 7.120797 Ht −.3511868 .0212466 −16.53 0.000 −.39325 −.3091236 _cons 113.6365 3.224366 35.24 0.000 107.253 120.02 SupP_CV Coef. Std. Err. t P>|t| [95% Conf. Interval] age −.1818182 .0233049 −7.80 0.000 −.227945 −.1356913 _cons 54.36364 1.13218 48.02 0.000 52.12274 56.60454