It might be a long-shot . . . but one of the potential side-effects of steroids is Avascular Necrosis:

"Avascular necrosis is death of bone tissue due to a lack of blood supply. This can lead to tiny breaks in the bone and the bone's eventual collapse.

..... Avascular necrosis of the wrist may cause wrist pain and finger weakness. You might feel less pain when you keep your hand still.

.... Common causes of avascular necrosis include ... Corticosteroids. It isn't clear how these anti-inflammatory medications, such as prednisone, cause avascular necrosis. People who take high doses of corticosteroids for long periods of time — for instance, people with chronic illnesses such as rheumatoid arthritis and lupus — are more likely to experience avascular necrosis."

http://www.mayoclinic.com/health/ava...crosis/DS00650

There have been people who've developed this after only ONE use of steroids, although this is rare.

Cherie