Table 2.

Grading of MMTs

	Kendall and Kendall14	AMA Impairment Rating Guide30
Grade 0	No perceptible muscle contraction	No perceptible muscle contraction
Grade 1	Muscle contraction palpable, but no motion	Muscle contraction palpable, but no motion
Grade 2	Motion of the part only with gravity reduced	Motion of the part only with gravity reduced
Grade 3	“… a muscle can hold the part in test position against the resistance of gravity but cannot hold if even slight pressure is added.”	Muscle can hold the part in the test position against gravity alone.
Grade 4	Muscle holds test position against some pressure but breaks away.	Patient can move the part through the full active range of motion against “some” resistance.
Grade 5	Muscle holds test position against “full pressure.”	Patient can move the part through the full active range of motion against “full” resistance.

AMA, American Medical Association.