Table 1.

Muscle physiological cross-sectional area (PCSA, mm²) for each side of the spine at different insertion levels and maximum muscle stress for each individual muscle group (in parentheses, MPa).

Local muscles	ICPL(0.846)	LGPL(0.846)	PM(0.846)	MF(0.846)	QL(0.846)
T12	–	–	211	–	128
L1	108	79	272	216	88
L2	154	91	262	314	80
L3	182	103	364	249	75
L4	189	110	239	410	70
L5	–	116	115	218	–
Global muscles	ICPT(0.846)	LGPT(0.846)	IO(0.846)	EO (0.846)	RA(2.21)
Thorax	548	1,109	624	624	260