Table 3.

A breakdown of the reviewed metrics based on the underlying anatomy.

Anatomy of interest	Number of papers	Metric
Hip	29	- MRI: development of muscle-to-fat ratio, volume atrophy, development of cross-sectional area, joint effusion, quality of tendons/nerves/fascias, T2-signal increase (21, 23, 26, 27, 30, 32, 33, 35, 37, 38, 40, 41, 43, 71) - CT: development of cross-sectional area (32) - Surgical exposure: incision length (32) - Damaged surface area (45, 52–55) - Integrity of nerves/ligaments measured in-situ (45, 55) - Muscle biopsy (25) - Biomarkers for inflammation (6, 7, 9, 11, 12) - Biomarkers for muscle damage (6, 7, 9, 11, 12, 15, 18, 21–23) - Strength measurements (26, 27) - Scar size (18) - Electromyography: recruitment of motor units, signs of denervation (24)
Spine	15	- MRI: muscle-to-fat ratio development, muscle edema, development of cross-sectional area, T2-signal intensity (10, 17, 20, 28, 31, 34, 36, 39, 42, 44) - CT: muscle-to-fat ratio, development of cross-sectional area (19, 39) - Surgical exposure: volume of saline, incision length and depth (16, 48) - Biomarkers for muscle damage (10, 14, 16, 17, 19, 20, 57) - Biomarkers for inflammation (10, 14) - Strength measurements (28) - Electromyography: muscle activity, signs of denervation (19) - Drainage volume (29)
Knee	2	- Surgical exposure: perimeter of surgical site, measurement of exposed bone area, incision length (49) - Damage of muscle/tendon width (49, 56)
Elbow	1	- CT: arc of exposure (46)
Pelvis	1	- Surgical exposure: incision length (50)
Hand	1	- Sonography: volume of scar tissue (47)
Humerus	1	- Surgical exposure: incision length (51)
Femur	1	- Surgical exposure: incision length (13)