Are three phase bone scans alone useful for the diagnosis of osteomyelitis?
Three-phase bone scans can be positive for osteomyelitis if there is a focal area of intense radiotracer uptake. This is particularly true when a patient has a superficial area of infection, such as an ulcer or cellulitis. In such a case, the question to be answered is whether the underlying bone is affected, which can be readily detected on a three-phase bone scan. Increased uptake on all three phases of a bone scan can also occur in acute fractures, after surgical manipulation, metastatic disease, avascular necrosis, and Paget’s disease. If any of these other conditions are potentially expected, a three-phase bone scan by itself is not likely to be useful because of poor specificity.