Dr. Ronald Anderson, a Pennsylvania rheumatologist, can inject a bursa with painkillers in his office for about $80. (Bursas are fluid-filled sacs that reduce friction around joints. When they become temporarily inflamed it is called bursitis.) But when one of his patients had the condition treated by an orthopedist at a surgicenter with ultrasound guidance, the bill was almost $5,000, most of which the insurance company paid.
