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The principal limitations of radiography are that it is a two‐dimensional representation of a three‐dimensional object and that there can be a delay between injury and identification of structural change [11] (see Figures 5.12a and d and 5.13b). In the absence of displacement or distraction, fracture identification requires approximately parallel alignment of the osseous discontinuity and incident X‐ray beam. If there is trabecular injury only, intact overlying cortex may efface the fracture [12]. Recently formed, thin, woven bone (periosteal callus) is insufficiently mineralized for radiographic visualization [13] and can take two to three weeks to become apparent [14, 15]. It has been reported that for acute lytic lesions 30–50% bone loss is necessary for radiographic identification [15, 16]. In the digital era, more subtle changes can be identified, but, in basic terms, if the sum of the osteoclastic and osteoblastic processes is not sufficiently out of balance to change the recognizable radiographic density, a lesion may remain radiographically silent.