Fatty infiltration (%)

Young age

Middle age

Old age

F

Overall P-value

L5/S1

Multifidus

Right side

46.06 ± (15.574)

55.35 ± (14.933)

62.7 ± (17.363)

17.445

Over all P-value = 0.001*

Young VS Middle age = 0.001*

Young VS Old age = 0.001*

Middle VS Old age = 0.032*

Left side

46 ± (14.174)

55.86 ± (13.877)

64.22 ± (19.373)

21.366

Over all P-value = 0.001*

Young VS Middle age = 0.001*

Young VS Old age = 0.001*

Middle VS Old age = 0.010*

Erector spinae

Right side

52.13 ± (16.048)

59.83 ± (17.957)

63.66 ± (17.086)

7.665

Over all P-value = 0.001*

Young VS Middle age = 0.020*

Young VS Old age = 0.001*

Left side

51.28 ± (17.975)

59.69 ± (18.483)

66.46 ± (19.164)

10.627

Over all P-value = 0.001*

Young VS Middle age = 0.019*

Young VS Old age = 0.001*