Radiographic Anatomy of the Pediatric Lisfranc Joint.

BACKGROUND: Injuries to the Lisfranc joint in children and adolescents are rare. The incomplete ossification of the bones of the foot makes it difficult to detect injuries.The aim of this study was to determine age-specific radiographic measurements of the Lisfranc joint to provide guidance to the radiologist, emergency physicians, and surgeons to decrease misdiagnosis of Lisfranc injuries and improve detection. METHODS: We retrospectively reviewed all foot radiographs without traumatic injury made between August 2014 and February 2015 in all patients younger than 18. The attendance list of the Emergency Department and Outpatient Clinic of a level-1 trauma center were used. Using a non-weight-bearing anteroposterior-view of the foot the distance between the base of metatarsal 1 and metatarsal 2 (MT1-MT2) and the distance between the medial cuneiform (MC) and the base of metatarsal 2 (MC-MT2) were measured. Median normal values were calculated per age. RESULTS: A total of 352 patients between the age of 0 and 18 years were screened for eligibility. Excluded were 109 patients because of anatomic abnormality, a fracture, inadequate radiograph, pain at the base of the first metatarsal, second metatarsal or MC, persisting pain at the Outpatient Clinic checkup or no follow-up. Included in the analysis were 243 patients. CONCLUSIONS: The distance between the base of MT1-MT2 was constant below 3 mm. Measurements for both MT1-MT2 and MC-MT2 distance approached adult values at the age of 6. LEVEL OF EVIDENCE: Level III.

Diagnostic performance of the Bernese versus Ottawa ankle rules: Results of a randomised controlled trial.

PURPOSE: The Ottawa ankle rules (OAR) brought about a reduction of radiographs on the Emergency Department (ED). However, still 50% of patients with ankle injuries undergo unnecessary radiography. Compared to the OAR, the Bernese ankle rule (BAR) has an acclaimed 84% reduction in radiography without loss of sensitivity. The primary aim of this study was to compare the diagnostic accuracy and reproducibility of both rules. Furthermore, the ability of triage nurses to accurately interpret the BAR was assessed. METHODS: Participants were assessed by both the ED resident and the triage nurse, applying the OAR and the BAR. After standardised data collection, ankle and foot radiographs were performed in all patients. Sensitivity and specificity of both tests applied by both observers were obtained and compared by McNemar's test. Reproducibility was calculated with Cohen's kappa. RESULTS: A total of 203 patients with ankle trauma were included. For the OAR obtained by the ED residents, the sensitivity and specificity were 0.97 and 0.29, respectively. For the BAR, the sensitivity and specificity of the ED residents were 0.69 and 0.45, respectively. For the triage nurses, the OAR sensitivity and specificity were 0.86 and 0.25, respectively. The BAR sensitivity and specificity for the nurses were 0.86 and 0.40, respectively. The reproducibility of the OAR was 0.45, and for the BAR, it was 0.48. CONCLUSION: Both rules showed comparable reproducibility. Although the BAR showed a superior specificity compared to the OAR, its sensitivity was too low to promote clinical use. The triage nurses demonstrated too low sensitivity on both rules to allow safe application. Therefore, the OAR remain the decision rules of choice for ankle injuries despite its modest 'ruling out' capacity.