TABLE 2.
Evolution of PDFF in leg muscles in adults with BMD over 9 and 18 months of follow‐up.
| Muscles | Baseline | Month 9 | p value | SRM | Month 18 | p value | SRM |
|---|---|---|---|---|---|---|---|
| Biceps femoris long head | 45.4 ± 34.3 | 1.7 ± 2.1 | 0.001 | 0.82 | 2.7 ± 2.8 | <0.001 | 0.98 |
| Adductor magnus | 44.1 ± 32.6 | 1.6 ± 1.5 | <0.001 | 1.11 | 2.7 ± 2.6 | <0.001 | 1.04 |
| Semimembranosus | 42.9 ± 32.1 | 1.9 ± 2.3 | <0.001 | 0.83 | 2.7 ± 2.3 | <0.001 | 1.15 |
| Gluteus maximus | 41.8 ± 25.8 | 1.0 ± 1.4 | 0.002 | 0.70 | 3.1 ± 2.7 | <0.001 | 1.14 |
| Vastus lateralis | 39.1 ± 29.9 | 0.7 ± 2.6 | 0.212 | 0.28 | 2.5 ± 2.9 | 0.002 | 0.84 |
| Gluteus medius | 39.5 ± 25.8 | 1.7 ± 2.1 | 0.004 | 0.80 | 4.2 ± 4.4 | <0.001 | 0.95 |
| Vastus medialis | 38.0 ± 28.1 | 2.0 ± 3.0 | 0.002 | 0.66 | 3.1 ± 2.2 | <0.001 | 1.40 |
| Vastus intermedius | 35.6 ± 27.2 | 2.0 ± 2.1 | <0.001 | 0.92 | 3.0 ± 2.5 | <0.001 | 1.19 |
| Semitendinosus | 31.5 ± 29.5 | 1.2 ± 1.5 | 0.004 | 0.79 | 2.7 ± 3.4 | 0.001 | 0.78 |
| Gluteus minimus | 29.6 ± 22.6 | 0.8 ± 2.1 | 0.152 | 0.35 | 5.1 ± 6.6 | <0.001 | 0.78 |
| Adductor brevis | 27.9 ± 26.5 | 0.2 ± 2.9 | 0.610 | 0.07 | 2.1 ± 2.6 | 0.001 | 0.81 |
| Biceps femoris short head | 26.8 ± 25.2 | 1.5 ± 2.8 | 0.012* | 0.52 | 2.7 ± 3.5 | <0.001 | 0.78 |
| Rectus femoris | 23.0 ± 22.4 | 1.2 ± 2.3 | 0.046* | 0.51 | 2.2 ± 2.8 | 0.003 | 0.79 |
| Adductor longus | 23.1 ± 28.4 | 0.7 ± 1.0 | 0.014* | 0.64 | 2.4 ± 3.2 | 0.002 | 0.75 |
| Pectineus | 17.4 ± 24.1 | 0.7 ± 2.0 | 0.143 | 0.36 | 1.3 ± 2.0 | 0.006 | 0.67 |
| Gracilis | 17.1 ± 18.2 | 1.2 ± 1.6 | 0.002 | 0.75 | 2.7 ± 4.2 | 0.006 | 0.63 |
| Sartorius | 13.5 ± 12.6 | 0.7 ± 1.3 | 0.002 | 0.55 | 1.0 ± 2.0 | 0.020 | 0.48 |
| Hamstrings muscle group | 37.1 ± 30.0 | 1.3 ± 1.9 | 0.003 | 0.68 | 2.7 ± 2.7 | <0.001 | 1.00 |
| Adductors muscle group | 35.9 ± 29.1 | 1.4 ± 1.6 | 0.001 | 0.86 | 3.0 ± 2.9 | <0.001 | 1.02 |
| Quadriceps muscle group | 35.3 ± 26.7 | 1.5 ± 1.8 | <0.001 | 0.90 | 2.8 ± 2.3 | <0.001 | 1.23 |
| Total thigh muscles | 35.3 ± 25.8 | 1.3 ± 1.1 | <0.001 | 1.17 | 3.1 ± 2.4 | <0.001 | 1.29 |
| Gastrocnemius medialis | 33.6 ± 28.6 | 1.7 ± 2.3 | 0.007* | 0.74 | 5.5 ± 6.2 | <0.001 | 0.89 |
| Gastrocnemius lateralis | 23.7 ± 26.1 | 0.7 ± 1.6 | 0.080 | 0.44 | 4.0 ± 5.5 | <0.001 | 0.73 |
| Peroneus | 23.5 ± 19.2 | 0.4 ± 1.7 | 0.288 | 0.26 | 3.4 ± 3.3 | <0.001 | 1.01 |
| Soleus | 18.6 ± 15.7 | 0.6 ± 0.9 | 0.018* | 0.64 | 3.5 ± 4.0 | <0.001 | 0.87 |
| Tibialis anterior | 17.3 ± 16.2 | 0.6 ± 1.5 | 0.089 | 0.43 | 2.1 ± 2.6 | <0.001 | 0.82 |
| Extensor digitorum longus | 14.9 ± 13.3 | 0.5 ± 1.7 | 0.276 | 0.27 | 2.2 ± 2.0 | <0.001 | 1.13 |
| Flexor hallucis longus | 11.1 ± 8.8 | 0.9 ± 1.5 | 0.007* | 0.56 | 1.6 ± 1.5 | <0.001 | 1.08 |
| Popliteus | 9.3 ± 11.4 | 0.4 ± 1.7 | 0.358 | 0.22 | 1.7 ± 2.0 | <0.001 | 0.83 |
| Tibialis posterior | 8.5 ± 7.0 | 0.0 ± 0.9 | 1 | 0.01 | 1.3 ± 1.1 | <0.001 | 1.19 |
| Flexor digitorum longus | 6.6 ± 5.4 | 0.2 ± 1.4 | 0.099 | 0.13 | 1.5 ± 1.4 | <0.001 | 1.10 |
| Total lower leg muscles | 19.8 ± 15.6 | 0.6 ± 1.1 | 0.024* | 0.58 | 3.2 ± 3.2 | <0.001 | 0.99 |
Note: Muscles and muscle groups are ordered according to severity of muscle fat replacement at baseline. The baseline column shows the mean ± SD PDFF percentage for each muscle, and the 9‐ and 18‐month columns both show the absolute increase in PDFF percentage over this time compared to baseline. Significant p values are marked in bold, as well as SRMs with a large effect size (>0.80 following Cohen's rule). The asterisk (*) marks p values that were significant before Holm's correction for multiple testing.
Abbreviations: BMD, Becker muscular dystrophy; PDFF, proton density fat fraction; SD, standard deviation; SRM, standardized response mean.