What percentage of extremities show soft tissue swelling and regional osteopenia on initial CRPS imaging?

• A. 60%
• B. 80%
• C. 90%
• D. 100%

Answer: (B)

Early CRPS imaging often shows soft tissue swelling from edema and regional osteopenia from increased bone turnover due to autonomic dysfunction. The combination of both soft tissue swelling and regional osteopenia is the most typical radiographic pattern in the initial evaluation, and it occurs in about four-fifths of affected extremities. This makes it the best-supported choice, since not every case will demonstrate both features and timing matters—the appearance can be subtle or delayed, and some patients may have one change without the other or even normal initial X-rays. Therefore, about 80% is the most accurate representation of how often this specific imaging pattern appears early in CRPS.