Causes of Polymyalgia

The name Polymyalgia--also known as Polymyalgia rheumatica (PMR)--comes from the Greek term for muscle pain. This inflammatory disease results in stiff and achy muscles in the neck, shoulders, upper arms, hips and thighs. The disease affects people over the age of 50. For some patients, the onset of polymyalgia symptoms occurs suddenly.

Genetics and Environment

• According to the Mayo Clinic, the triggers of polymyalgia are not understood, but may result from a malfunction of the immune system (involving environmental and genetic factors).

Aging

• The natural process of aging also contributes to the development of polymyalgia.

Possible Form of Arthritis

• The American College of Rheumatology also notes that new evidence "suggests that PMR is an arthritis with a particular tendency to involve the shoulder and hip joints, and the bursae (or sacs) around these joints."

Viral Infection

• According to William C. Shiel, Jr., MD, medical writer for MedicineNet, one theory of polymyalgia involves the interaction between genetic factors and the environment: A person's immune system is stimulated by a viral infection.

Cancer Link

• Dr. Shiel also notes that, in rare cases, cancer is linked to polymyalgia. The cancer may cause an inflammatory immune response, manifesting as polymyalgia symptoms.