Radiographic Interpretation of Horses with Clinical Signs of Infection or Joint Disease

I. Radiographic Interpretation of Soft Tissue Infection 1. Cellulitis Radiographic evaluation of a horse with clinical signs of cellulitis is done primarily to determine the presence of a radiodense foreign body and signs of osteomyelitis. The radiographic findings to be evaluated with cellulitis are the presence of the following:

• Extracapsular soft tissue swelling (E-STS) • Radiodense foreign body • Gas in the soft tissues (Figure 3-1) • Peri osteal reaction or cortical destructive change in the area of the STS

E-STS is identified by increased density and a loss of normal soft tissue planes. Horses with chronic cellulitis often have a draining tract (Figure 3-2). These patients should have a special radiographic examination with a positive contrast agent injected into the tract. This special procedure is called “fistulography.”