Bursitis and tendonitis can have many various causes, but the most common is repetitive activity.  This can be from exercise such as running or tennis, work such as using a hammer or typing on a computer, or a hobby such as golf or sewing. Physical therapy can be very effective for treating bursitis or tendonitis of the shoulder, elbow, hip, knee, ankle, etc. Physical therapy will focus on reducing pain, swelling, stiffness and related weakness and then on improving posture and body mechanics in order to prevent future recurrences.