It is typical for physicians to order prereduction and postreduction radiographs for patients who present with evidence of an anterior shoulder dislocation. The arguments given against routine prereduction films include the following: (1) patients with anterior shoulder dislocation are often in considerable pain when they present for care; and (2) a delay at attempting reduction will prolong the amount of time the patient is in pain and may worsen muscle spasms. Shuster and associates assessed the usefulness of prereduction radiographs in a series of patients who presented to ski-area clinics and a rural emergency department.
The patient population included skiers who presented with a suspected shoulder dislocation. All patients who presented with a shoulder injury were initially examined by an attending physician. Data collected at the time of this examination included questions about the patient's history, the circumstances of the injury, discomfort and range of motion. Before obtaining prereduction radiographs, physicians were asked to rate their confidence in the diagnosis of anterior shoulder dislocation on a 10-point scale (zero = “no confidence” and 10 = “certain confidence”). All patients then had prereduction radiographs followed by manual reduction and postreduction radiographs.
The study population included 97 patients with a mean age of 33.5 years. Most injuries occurred while the patients were engaged in downhill skiing or snowboarding. The physician was certain (confidence score of 10) that the patient had a dislocation in 69 of 97 patients. A dislocated shoulder was confirmed in all 69 of those patients. The physician was certain in nine of 97 patients that the shoulder was not dislocated. None of the nine had a shoulder dislocation. In the remaining 19 patients, the diagnosis of dislocation was not certain: 16 of these patients did have a dislocation, and three did not. Fractures were found on seven of the prereduction radiographs and on 11 of the postreduction radiographs. No fracture was seen on a prereduction radiograph that was not also clearly visible on the postreduction radiograph. None of the fractures required surgical intervention.
The authors concluded that shoulder dislocation is often readily apparent from the history and physical examination. When an experienced physician is certain of the diagnosis of anterior shoulder dislocation, prereduction radiographs are not clinically useful, as they do not alter management.