From: Endoscopic versus open radial artery harvest and mammario-radial versus aorto-radial grafting in patients undergoing coronary artery bypass surgery: protocol for the 2 × 2 factorial designed randomised NEO trial
Grade 0
No muscle movement
Grade 1
Muscle movement without joint motion
Grade 2
Moves with gravity eliminated
Grade 3
Moves against gravity but not resistance
Grade 4
Moves against gravity and light resistance
Grade 5
Normal strength