Diagnostic accuracy of Fresno-Quebec Rules and risk factors for an associated fracture in patients presenting to the emergency department with anterior shoulder dislocation: A retrospective study.

Abstract

Anterior shoulder dislocation is the most common shoulder injury in patients presenting to the emergency department (ED). Up to 25% of these injuries are fracture-dislocations. In general, the standard approach is to obtain plain radiographs before and after reduction. Fresno-Quebec Rules (FQR) are described to identify the patients who require an x-ray before reduction to reduce radiation exposure and delays in treatment. We aimed to evaluate the efficacy of clinical predictors used in the Fresno-Quebec algorithm for detecting a shoulder fracture-dislocation. Records of patients who presented to the Emergency Department with presumed shoulder dislocation were retrieved and retrospectively analyzed according to 'Fresno-Quebec Rule (FQR)'. Sensitivity, specificity, and predictive values of FQR for detecting associated injuries were calculated. Eighty-nine (65.9%) men and 46 (34.1%) women were included. The mean age of patients was 46 years (16-89). Ninety-nine (73.3%) of the cases had their shoulder dislocated for the first time, whereas 36 (26.7%) patients had a recurrent dislocation. Fifty percent of the patients (18 cases) with recurrent dislocation presented with an atraumatic episode. The remaining 18 patients with a history of recurrent dislocations had their shoulder dislocated as a result of trauma, and four (22%) of them had fracture-dislocation. Using the Fresno-Quebec rules yielded 100% specificity for the diagnosis of fracture-dislocation. The severity of the injury mechanism was not predictive in traumatic but recurrent dislocations. Only one of four patients with a fracture-dislocation in the traumatic recurrent dislocation group had high energy trauma. FQR has 100% sensitivity in detecting fracture-dislocations in patients admitted to ED with anterior shoulder dislocation. It utilizes simple parameters that are easy to use and recall. Using these rules, 30% of unnecessary radiographs can be avoided, saving time and money and reducing radiation exposure in anterior dislocations.