Associations between muscle relative T2 signal and corresponding regional, clinical and electrophysiological measures
| Parameter associated with relative T2 signal | Regression coefficient (95% CI) | P value |
| Age | 0.001 (−0.002 to 0.004) | 0.395 |
| Gender | 0.014 (−0.076 to 0.104) | 0.749 |
| Days from symptom onset | 0.00004 (−0.00004 to 0.00012) | 0.345 (0.227) |
| ALSFRS-R | −0.009 (−0.017 to –0.001) | 0.023 (0.022) |
| MRC summary score | −0.003 (−0.0068 to 0.0001) | 0.060 (0.078) |
| MRC score right biceps | −0.017 (−0.064 to 0.030) | 0.469 (0.794) |
| MRC score left biceps | −0.079 (−0.147 to –0.011) | 0.024 (0.037) |
| MRC score right TA | −0.107 (−0.142 to –0.071) | <0.001 (<0.001) |
| MRC score left TA | −0.069 (−0.091 to –0.046) | <0.001 (<0.001) |
| Dynamometry right TA | −0.005 (-0.007 to –0.002) | <0.001 (<0.001) |
| Dynamometry left TA | −0.005 (−0.007 to –0.003) | <0.001 (<0.001) |
| MUNIX biceps | −0.001 (−0.0020 to –0.0002) | 0.015 (0.077) |
| CMAP biceps | −0.027 (−0.049 to –0.005) | 0.019 (0.092) |
| MUSIX biceps | −0.0007 (−0.0063 to 0.0048) | 0.783 (0.703) |
| MUNIX TA | −0.0018 (−0.0029 to –0.0007) | 0.003 (0.001) |
| CMAP TA | −0.055 (−0.082 to –0.028) | <0.001 (<0.001) |
| MUSIX TA | −0.0008 (−0.0032 to 0.0015) | 0.460 (0.509) |
Parameter estimates refer to unadjusted coefficients derived from regression models, with 95% CI in parentheses. P values refer to regression models unadjusted and, in parentheses, adjusted for age and gender. Significant results after correction for multiple comparisons are highlighted in bold.
ALSFRS-R, amyotrophic lateral sclerosis functional rating scale-revised; CMAP, compound muscle action potential; MRC, Medical Research Council; MUNIX, motor unit number index; MUSIX, motor unit number size; TA, tibialis anterior.