Table II.
Net relative functional volume and relative functional atrophy ratio of lumbar multifidus muscles for the various stages of LDH duration and ages at the L4-L5 and L5-S1 segmental levels.
| Segmental level | ||||||
|---|---|---|---|---|---|---|
| L4-L5 | L5-S1 | |||||
| Duration of LDH | Youth group | Elderly group | P-value | Youth group | Elderly group | P-value |
| Acute | ||||||
| Net volume | 497.70±510.47 | 593.84±421.64 | 551.23±665.25 | 726.99±759.27 | ||
| Atrophy ratio | 0.08±0.07 | 0.11±0.09 | 0.10±0.13 | 0.12±0.14 | ||
| Remittent | ||||||
| Net volume | 207.42±671.38 | 140.52±767.18 | 314.78±755.11 | 107.52±654.84 | ||
| Atrophy ratio | 0.09±0.06 | 0.11±0.09 | 0.09±0.09 | 0.09±0.08 | ||
| Recovery | ||||||
| Net volume | −340.02±391.26 | −452.62±503.18 | −542.42±626.21 | −857.58±604.20 | ||
| Atrophy ratio | 0.05±0.06 | 0.10±0.06 | 0.09±0.06 | 0.15±0.10 | ||
| Sub-acute | ||||||
| Net volume | −354.10±729.14 | −671.97±672.10 | −516.48±934.97 | −674.87±570.32 | ||
| Atrophy ratio | 0.10±0.11 | 0.13±0.11 | 0.11±0.07 | 0.14±0.09 | ||
| Chronic | ||||||
| Net volume | −620.56±353.97 | −678.97±671.02 | −650.67±699.39 | −1214.99±1019.73 | 0.048 | |
| Atrophy ratio | 0.09±0.05 | 0.13±0.12 | 0.15±0.11 | 0.16±0.13 | ||
Data are presented as the mean ± standard deviation. LDH, lumbar disc herniation.