Yes, SPINALS is a Scrabble word!

Letter values in Scrabble US: S 1, P 3, I 1, N 1, A 1, L 1, S 1.

Is it a valid word?

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

anesthesia of the lower half of the body; caused by injury to the spinal cord or by injecting an anesthetic beneath the arachnoid membrane that surrounds the spinal cord

Also: spinal anesthesia, spinal anaesthesia.