The editorial by Orchard et al1 is a timely reminder of the mounting evidence of the negative bioeffects of imaging studies utilising ionising radiation in paediatric populations. This applies especially to CT and nuclear medicine, in which the doses are higher than X-rays, and which are much more commonly performed than in fluoroscopy. As the authors point out, these considerations are highly relevant to the practice of sports medicine, as the patients are often young, and bony injuries are commonly investigated using CT and nuclear medicine. So how are clinicians to integrate data from these increasingly well-designed studies2 into recommendations that will still allow accurate and timely diagnosis of sports-related pathology? As a professor of musculoskeletal radiology, I share the following thoughts:

• Appropriateness is key

There have been a number of studies that correctly point out the need to determine whether ANY study is needed to investigate a clinical condition, before determining which study. For example, substituting an MRI for a CT in an adolescent with uncomplicated low back pain is not likely to change the outcome. One study3 found that over half of the requests for lumbar spine MRI, although not restricted to children, were inappropriate or of uncertain value, using standard guidelines. However, all parties agree that red flag symptoms (eg, motor weakness and fever) warrant immediate imaging work-up and under these conditions, MRI is the best choice, due in part to the lack of ionising radiation. As Orchard et al point out, there are a number of sources for such guidelines, and these include the American College of Radiology (http://www.acr.org). Radiologist consultations are also very valuable in determining the best test, if any. Finally, paperless, automated order-entry information technology software can include ‘appropriateness criteria’; this can digitally guide the clinician to the best diagnostic work-up. The method has a high rate of clinical acceptance.4

• Age matters

Although the Orchard editorial clearly emphasises that the cancer risk they discuss is restricted to the paediatric population, this point bears a heavy underscore. Researchers5 agree that above age 40, risk from radiation-induced cancer falls dramatically. Nonetheless, for radiation safety, as well as economic and clinical reasons, including the risk of additional investigation or other interventions that may occur from false-positive examinations, appropriateness for an imaging test should always be ensured.

• Baby and the bathwater

Even though an important cautionary note regarding CT and nuclear medicine examinations in younger patients is mandated, this is not to say that each of these tests still does not have an important and sometimes life-saving role to play. Examples in which CT, with modern dose-reduction strategies6 of course in place, is still the first examination of choice for sports injuries include trauma (especially multisystem trauma), certain high-risk stress fractures (eg, femoral neck, tarsal navicular), loose bodies (for presurgical localisation), cortical lesions (eg, Brodie's abscess) and it also acts as a guide for intervention (eg, radiofrequency ablation for osteoid osteoma). Nuclear medicine three-phase bone scanning remains an excellent test to exclude osteomyelitis and osteoid osteomas in scenarios in which MRI is unavailable.

• Knowledge is power…and safety

There is no question that education of clinicians and patients is critical to reduce the number of inappropriate imaging examinations. Recently in Canada, the majority of clinicians in a survey7 indicated erroneously that CT scans had the lowest radiation dose among imaging studies. Education is needed through continuous professional development strategies, radiation safety modules that are part of hospital/facility privileging and the decision support tools that have been previously mentioned. An educated physician is an important precursor to an educated patient.

The practice of Sports and Exercise Medicine has long relied on imaging to provide important information that, when combined with traditional history/physical and lab and other tests, directs the clinician to the correct diagnosis, and the patient to an effective treatment plan. CT and nuclear medicine, as well as plain radiographs and fluoroscopy, will remain part of this imaging arsenal; however, the Orchard editorial reminds us of the work we have to do in applying these tests with ionising radiation to the right patient, for the right reason, at the right time.