We have found two studies to be of special interest (see citations below). Both have been done in a primary care setting with one-year follow up. One study compares corticosteroid injection with physical therapy (ultrasound, manipulation and exercise) and a wait-and-see group. The other compares corticosteroid injection with naproxen orally and placebo-medication. Both conclude that corticosteroid injection is a safe and effective treatment as pain-relief during the first 6 weeks, and that the effect of this treatment is better than physical therapy, wait-and-see and naproxen orally within the same time-frame. Physical therapy in one study gives some, but not statistically significantly better long-term (one year) effect than wait-and-see treatment.