As imaging techniques are ever-evolving, this article aims to provide a brief overview of the various modalities including their limitations. The ability of imaging for evaluation of implant osseo-integration will be addressed and also the role of imaging in assessing septic and aseptic loosening, with a particular focus on adverse tissue reactions, will be discussed. Specific features when imaging the big joints such as shoulder, hip, knee and ankle joint will also be outlined.Overall, a lack of standardisation and validity was noted and despite the gross variety of imaging modalities, there is no technique covering all aspects required for evaluation of implant fixation and septic and aseptic loosening. Each imaging modality has a role, depending on the information required and anticipated. The choice of imaging technique should not be primarily based on medical considerations but also on availability, accessibility, expertise and costs. Plain radiographs alone have been recommended in cases of suspected peri-prosthetic joint infections, given the lack of evidence for additional imaging techniques in this context. For aseptic loosening, ultrasound and plain radiographs may serve as initial screening tools. Metal artefact reducing sequences (MARS) MRI are advancing cross-sectional imaging and are likely to promote their role in patient evaluation.We conclude that imaging is one essential part in the work-up of patients with total joint replacements, within a specific clinical context. Close teamwork between experienced radiologists and orthopaedic surgeons is required for optimal patient care.Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160058. Originally published online at www.efortopenreviews.org

A 43-year-old male patient with underlying diabetes mellitus presented with lower abdominal pain radiating to left thigh. He was hemodynamically stable, but appeared lethargic. Both iliac fossae were tender, and crepitus appreciated along the anteromedial aspect of the left thigh. The patient initially responded well to treatment and was discharged; however, he was re-admitted several months later due to recurrent collection showing the growth of Klebsiella pneumoniae in the culture and succumbed to sepsis due to deep-seated intramuscular abscess and lung empyema. In conclusion, psoas abscess is a condition that can mimic various pathologies related to the lower abdomen and, therefore, clinicians should always have a high index of suspicion to prevent a missed diagnosis. Early detection may yield good outcomes, if managed with adequate surgical drainage and appropriate antibiotics.