What is the cause of painful knots in the back and chest area? sometimes massage helps get rid of them.

Possibly spasm: If you have "knots" in your back and chest that are relieved with massage, it may be spasm. If it were some type of growth they would not go away with massage. If they keep recurring, the question is if they have some type of underlying cause such as a pinched nerve, for example. Consider seeing your physician to discuss.

Knots: are hyperirritable spots in muscle or fascial (a type of connective/connecting) tissue. Muscle fibers run in all different directions..muscles are layered on top of each other from our heads to our toes. When we stay in one position all day (desk jobs, etc) the fibers start to stick to each other/become adhered. While common, not harmless. Chronic muscle stress creates micro-tearing and scarring.