Accuracy and dispersal of subacromial and glenohumeral injections in cadavers.

Abstract

"Blind" shoulder injections are often inaccurate and infiltrate untargeted structures. We tested a hypothesis that optimizing certain anatomical and positional factors would improve accuracy and reduce dispersal. We evaluated one subacromial and one glenohumeral injection technique on cadavers. Mean accuracy was 91% for subacromial-targeted and 74 and 91% (worst- and best-case scenarios) for joint-targeted injections. Mean dispersal was 19% for subacromial-targeted and 16% for joint-targeted injections. All results bettered those reported previously. These "optimized" techniques might improve accuracy and limit dispersal of blind shoulder injections in clinical situations, benefiting efficacy and safety. However, evaluation is required in a clinical setting.