US-guided aspirations of soft tissue fluid collections and joint effusions is becoming increasingly common [14]. With the use of color Doppler, vascularity and hyperemia can be assessed without the administration of IV contrast. If needed, US can examine the contralateral side for comparison or extend the area of imaging of suspected infection. Absence of a fluid essentially excludes the diagnosis of septic arthritis, tenosynovitis, and abscess. Gaspari et al [14] reported that US correctly diagnosed an abscess in 29 out of 30 patients and no abscess in 30 of 35 patients with an alternative diagnosis. In comparison, CT correctly diagnosed 23 out of the same 30 patients with abscess and correctly diagnosed 32 of the 35 patients without an abscess. They reported the overall sensitivity and specificity of US for the diagnosis of an abscess as 96.7% and 85.7%, respectively, whereas CT had 76.7% sensitivity and 91.4% for specificity. They concluded that both CT and US are accurate for diagnosing superficial abscesses. US can evaluate the internal characteristics of the abscess cavity, such as necrosis or debris, and associated pathology like foreign bodies, fistulas, and vascular injury. For deeper soft tissue structures and the evaluation of adjacent bone involvement, US is limited compared with MRI and CT. Variant 3: Suspected osteomyelitis. Initial radiographs normal or with findings suggestive of osteomyelitis. Next imaging study. For osteomyelitis, the body regions covered are ankle, chest, elbow, femur, foot, forearm, hand, hip, humerus, knee, pelvis, shoulder, tibia/fibula, wrist. 3-Phase Bone Scan and WBC Scan and Sulfur Colloid Scan Area of Interest These 3 scans are ordered in progression to increase the accuracy of diagnosing osteomyelitis.
Suspected Osteomyelitis Septic Arthritis or Soft Tissue Infection Excluding Spine and Diabetic Foot PCAs. US-guided aspirations of soft tissue fluid collections and joint effusions is becoming increasingly common [14]. With the use of color Doppler, vascularity and hyperemia can be assessed without the administration of IV contrast. If needed, US can examine the contralateral side for comparison or extend the area of imaging of suspected infection. Absence of a fluid essentially excludes the diagnosis of septic arthritis, tenosynovitis, and abscess. Gaspari et al [14] reported that US correctly diagnosed an abscess in 29 out of 30 patients and no abscess in 30 of 35 patients with an alternative diagnosis. In comparison, CT correctly diagnosed 23 out of the same 30 patients with abscess and correctly diagnosed 32 of the 35 patients without an abscess. They reported the overall sensitivity and specificity of US for the diagnosis of an abscess as 96.7% and 85.7%, respectively, whereas CT had 76.7% sensitivity and 91.4% for specificity. They concluded that both CT and US are accurate for diagnosing superficial abscesses. US can evaluate the internal characteristics of the abscess cavity, such as necrosis or debris, and associated pathology like foreign bodies, fistulas, and vascular injury. For deeper soft tissue structures and the evaluation of adjacent bone involvement, US is limited compared with MRI and CT. Variant 3: Suspected osteomyelitis. Initial radiographs normal or with findings suggestive of osteomyelitis. Next imaging study. For osteomyelitis, the body regions covered are ankle, chest, elbow, femur, foot, forearm, hand, hip, humerus, knee, pelvis, shoulder, tibia/fibula, wrist. 3-Phase Bone Scan and WBC Scan and Sulfur Colloid Scan Area of Interest These 3 scans are ordered in progression to increase the accuracy of diagnosing osteomyelitis.