Figure 1.

Examples of gMFA with different severities according to Goutallier grading scores based on CT pelvis images. (A) The area marked with 0 is an example of a score of 0 with no fat in the gluteus maximus, which was rare in the investigated population. The gluteus medius marked with 1 represented a score of 1 with intramuscular fatty steaks. (B) The area marked with 2 exemplified a score of 2 in gluteus maximus with mild atrophy, in which the proportion of fat infiltration was less than that of muscle. Nearby, an exaggerated fat infiltration could be found in the gluteus medius, marked by 3, where the proportion of fat and muscle were subjectively equal. The gluteus minimus, marked by 4, showed the most profound fat infiltration, where fat infiltration exceeded in quantity.