Figure 2: Localization of the gluteal site localization adopted from Canadian Journal of Association of Radiologist (CARJ) (a and b). Section which is 1 cm above the lowermost point of the SI joint is identified (Y in Figure a). Corresponding axial section at the Y location showing site of injection which is 5 cm away from the SI joint. The subcutaneous fat thickness measured (red double arrow). (c) Length of the commonly used needle in our hospital. (d) The correlation between the fat thicknesses measured in the dorsogluteal site and venterogluteal site. (f) The correlation between the fat thicknesses measured by the dorsoglteal site localization method and CAJR method