Table 2.

Muscle mass and atrophy

Muscle	Study	Specific Muscle	Measurement tool/unit	Intervention				Control
				Pre-op		Post-op		Pre-op		Post-op
				Involved leg	Uninvolved leg	Involved leg	Uninvolved leg	Involved leg	Uninvolved leg	Involved leg	Uninvolved leg
Quadriceps femoris	Dreyer 2013 [21]	Rectus femoris	MRI/cm3	120 ± 11	140 ± 12	110 ± 11	136 ± 12	133 ± 13	150 ± 16	108 ± 9	135 ± 14
	Dreyer 2018 [35]	NA	MRI/AU	48.66 ± 3.45	55.49 ± 3.87	43.87 ± 2.93	54.41 ± 3.65	44.81 ± 3.09	49.98 ± 3.05	38.31 ± 2.39	46.44 ± 2.94
	Ueyama 2023 [37]	Rectus femori	Ultrasound/mm2	258.0 ± 88.7	NA	326.0 ± 91.53	NA	305.2 ± 97.2	NA	345.7 ± 97.1	NA
	Nishizaki 2015 [30]	Rectus femoris	CT scan/cm2	528±164	502±87	572±171	548±130	542±164	577±140	506±164	533±168
	Ninomiya 2023 [31]	Rectus femoris + vastus intermedius	Ultrasound/mm	27.05 ± 6.92	32.64 ± 7.26	31.62 ± 6.84	36.48 ± 6.43	28.51 ± 7.24	32.84 ± 6.52	29.79 ± 6.90	33.21 ± 5.49
	Li 2024 [39]	NA	Tape measure/cm	44.6 ± 0.93	NA	45.3 ± 0.83	NA	44.1 ± 1.12	NA	44.2 ± 1.08	NA
Hamstrings	Dreyer 2013 [21]	NA	MRI/cm3	142 ± 13	147 ± 13	129 ± 11	142 ± 12	154 ± 17	150 ± 15	126 ± 16	137 ± 14
	Dreyer 2018 [35]	NA	NA	69.32 ± 4.05	69.37 ± 4.19	63.76 ± 3.41	67.50 ± 3.75	63.86 ± 3.33	63.64 ± 3.33	55.93 ± 2.91	58.75 ± 3.05
intermuscular adipose tissue (IMAT)	Dreyer 2013 [21]	NA	NA	66 ± 7	62 ± 8	69 ± 8	61 ± 7	46 ± 7	40 ± 5	44 ± 6	39 ± 5
	Ninomiya 2023 [31]	NA	NA	65.10 ± 14.35	59.15 ± 10.96	59.67 ± 10.26	54.56 ± 9.09	54.48 ± 10.97	61.92 ± 7.12	62.27 ± 14.50	56.11 ± 9.43
AMA	Ikeda 2019 [28]	NA	NA/cm2	48.4±11.6		47.0±11.6		61.3±19.9		58.5±12.8

QM quadriceps muscle, IMAT intermuscular adipose tissue, HM hamstring muscle, AU arbitrary unit, F-U follow-up, AMA upper arm muscle cross-sectional area