Yes, FLEXURES is a Scrabble word!

Letter values in Scrabble US: F 4, L 1, E 1, X 8, U 1, R 1, E 1, S 1.

Is it a valid word?

FLEXURES is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

the state of being flexed (as of a joint)
an angular or rounded shape made by folding
act of bending a joint; especially a joint between the bones of a limb so that the angle between them is decreased