Ultrasound-Guided vs Landmark-Guided Intra-articular Lidocaine for Anterior Shoulder Dislocations

Shoulder dislocations are the most common presenting joint dislocation to the Emergency Department (ED). Procedural sedation is often used for shoulder reduction, but is resource intensive, prolongs ED stay, and poses many risks to the patient. Landmark-guided intra-articular lidocaine (LGIL) is a commonly used alternative to procedural sedation in shoulder reduction; however, the injection can miss the intra-articular space. Ultrasound guidance improves accuracy of procedures. Our primary objective is to evaluate if Ultrasound-guided intra-articular lidocaine (UGIL) is more effective than LGIL for anterior shoulder dislocations by comparing the rate of progression to procedural sedation.

We conducted a randomized prospective superiority study to investigate whether UGIL for anterior shoulder dislocations leads to less failure of closed, awake reductions than LGIL. Adult patients were enrolled after radiology confirmed anterior shoulder dislocation. Initial analgesia was administered at the provider’s discretion. Patients were randomized to receive UGIL or LGIL using 15 ml of 1% lidocaine. The emergency provider determined which shoulder reduction technique to use. Reduction failure was defined by 3 failed attempts or if the patient requested early termination. After failure, the patient was advanced to procedural sedation. Additional data points collected included pain scores, patient satisfaction, and provider confidence.

A total of 35 patients with anterior shoulder dislocations were enrolled. 15 patients received UGIL and 20 patients received LGIL. Patients who received UGIL were advanced to procedural sedation for closed reduction less often than patients who received LGIL (12% vs. 35%, p>0.05). Patients who received UGIL were more likely to request the same analgesia in the future compared to patients who received LGIL (80% vs. 60%). Patients who received UGIL had a lower pain reduction score out of 10 than patients who received LGIL (2.13 vs. 3.05). Comparing the UGIL group to the LGIL group, providers had similar levels of confidence in successfully injecting the intra-articular space (73% vs. 75%).

Our study suggests that UGIL is more effective than LGIL in anterior shoulder dislocation reductions by demonstrating a reduced rate of progression to procedural sedation.