Tendinitis is perhaps the most common shoulder problem you may experience. Tendinitis is inflammation of a tendon. When it happens in the shoulder, your rotator cuff tendons or biceps  tendons are inflamed, usually as the result of being pinched.

Bursitis often accompanies tendinitis, although it can occur independently. Bursitis is inflammation of the bursae, the sacs that help cushion the rotator cuff from the boney front edge of the shoulder blade (acromion).

Both result in shoulder pain.