You are describing keratosis pilaris, a
hereditaryHereditary amyloidosis
Pseudohypoparathyroidism condition which produces bumps of keratin protein in the hair openings of the upper arms and back. You can smooth down the bumps if you apply an over-the-counter lotion containing ammonium lactate and exfoliate with a Buf Puf or loofah (ask your druggist.) Your dermatologist can offer other therapies if you wish. Or you can do what most people with this
commonCommon cold condition do--just ignore it. But don't pick or squeeze them--just makes the bumps worse and more noticeable.
Best.
Dr. Rockoff