Abstract
In order to evaluate the age related changes of skeletal muscle image in Computed Tomogram (CT), trunk muscle at the 4th lumbar spine in 73 CT pictures (males: 33, females: 40) were observed macroscopically. The images were compared with the crosssectional area of each component section. Following results were obtained.
1. The cross-sectional area of each trunk muscle showed a clear age-related decrease in male, but only a tendency of marginal decrease was suggested in major psoas and erecter spinal muscles in femal.
2. Low density area in the skeletal muscle with associated morphologic changes tended to appear more frequently with advancing age and they were more pronounced in females than in males.
3. These changes showed a tendency of occurrence along with an increase of abdominal cavity on the abdominal rectum muscle and lateral abdominal muscles in both sexes, and tended to follow the changes of subcutaneous fat on the quadrate lumber and erect spine muscles in female.
