Study to outline the efficacy and illustrate techniques for steroid injection for trigger finger and thumb.

AIM: To outline the efficacy of a steroid injection in treating trigger finger. Our study defines the anatomy of the A1 pulley, and suggests methods for simple and safe flexor sheath injection for trigger finger and thumb.
METHOD: Systematic review of published literature on trigger finger and thumb and its treatment, particularly steroid injection. The use of the knowledge of the superficial landmarks of the A1 pulley with the techniques described were combined to provide a comprehensive guide to injecting steroids in patients with trigger finger and thumb.
RESULTS: Several studies are outlined, which provided evidence to suggest that a steroid injection into the flexor sheath of the affected digit is successful in treating most of the patients. Methods of identifying the superficial landmarks of the A1 pulley and of approaching the pulley without injury to surrounding structures are also outlined in the literature. Two different techniques used to infiltrate the flexor sheath were described.
CONCLUSION: Steroid injection in the flexor sheath at the level of the A1 pulley is an effective method of treating patients with trigger finger and should be considered as the preferred treatment. Specific anatomical landmarks and methods allow the procedure to be carried out without fear of inadvertent damage to surrounding structures.