Intra-articular lidocaine versus intravenous meperidine/diazepam in anterior shoulder dislocation: a randomised clinical trial.

BACKGROUND Anterior shoulder dislocation is one of the most common complaints of patients referred to emergency departments. Intravenous opiates and benzodiazepines are traditionally prescribed in order to relieve the pain in this group of patients; however, complications always pose a problem. OBJECTIVE To compare the pain relief and complications following intra-articular lidocaine and intravenous meperidine/diazepam in patients with anterior shoulder dislocation. METHODS 48 patients with non-habitual traumatic anterior dislocation of the glenohumoral joint admitted to Imam Khomeini hospital emergency department were enrolled in this randomised clinical trial. They were divided into two groups: one group of patients received intra-articular lidocaine 1%, while the other received intravenous meperidine and diazepam. Closed reduction using the countertraction-traction method was performed by a single person in all the patients. Utilising a 100 mm visual analogue scale, each patient's pain was recorded before injection, before reduction, and after reduction. RESULTS Mean pain (mm) recorded before injection, before reduction, and after reduction in the intra-articular lidocaine group was 84.3 (95% confidence interval (CI) 79.8 to 88.8), 52.6 (95% CI 45.2 to 60.1), and 27.3 (95% CI 19.9 to 34.7), respectively. The corresponding rates in the intravenous meperidine/diazepam group were 83.2 (95% CI 79.2 to 87.2), 57.9 (95% CI 53.8 to 62.0), and 23.9 (95% CI 18.9 to 28.8), respectively. Both groups demonstrated a similar significant decline in pain after injection (p<0.005). No severe complications were reported in either of the groups. CONCLUSION Intra-articular injection of lidocaine before closed reduction of anterior shoulder dislocation produces the same pain relief as intravenous meperidine and diazepam.