In the regular follow-up of patients after bone fracture, the course of fracture consolidation is reviewed by conventional, two orthogonal projection radiographs. Therefore, the development of a nonunion can be monitored clinically and through imaging. In case of insufficient fracture healing, early modification of osteosynthesis like dynamization of an intramedullary nail can influence Selleck Kinase Inhibitor Library the further course of healing and reorient a delayed union or even some nonunions

towards adequate bone consolidation. Patients with a manifest nonunion usually complain about pain in the fracture area with, and sometimes even without, weight bearing. The affected bone is usually sensitive upon pressure and patients are not able to bear full weight [17]. In cases of suspected infectious genesis of nonunion with possible additional symptoms like reddening, hyperthermia and elevated body temperature, laboratory analysis should be obtained for infectious parameters such as white blood cell count and inflammation parameters [19]. After clinical and laboratory evaluation, conventional radiographs in two orthogonal planes represent the basic diagnostic imaging tool, where the radiolucent gap between bone endings is associated to closure of intramedullary check details canals of diaphyseal bone endings. Besides, the basic characteristics

of the nonunion (status of consolidation, hypertrophic/atrophic nonunion, segmental bone defects) can be evaluated for a more precise diagnosis. If the amount of consolidation or the radiological signs of nonunion do not become obvious in conventional radiographic evaluation, a computer tomography (CT) of the affected region is mandatory. Three-dimensional reconstructions and exact illustration of the fractured region, with the amount and location of possible callus bridges, can be evaluated through CT imaging (Fig. 3). In some cases, especially with doubtful aseptic pathogenesis

of the non-union, additional diagnostic evaluation should be performed. While bone scintigraphy no longer represents the state of the art diagnostic imaging tool, fluorodeoxyglucose positron emission computer tomography Verteporfin (FDG-PET-CT) has become more and more relevant in clinical daily routine. This imaging tool combines the exact imaging from the CT with additional information about the metabolism of the examined area with a high diagnostic sensitivity for a chronic osteitis. FDG-PET-CT has been shown to be of good diagnostic accuracy in bone pathology discrimination [20] and chronic osteomyelitis [21]. The combination of clinical examination, laboratory analysis and radiological imaging by conventional radiographs, CT and possibly PET-CT should be sufficient for a clear diagnosis.