Corticosteroid injections for trigger digits: is intrasheath injection necessary?

Ninety-five patients with 107 trigger digits were divided into 2 groups and studied prospectively to evaluate steroid injection placement and efficacy. In 1 group, an attempt was made to deliver 1 injection into the tendon sheath at the A1 pulley. In the other group, 1 injection infiltrated the subcutaneous tissues overlying the A1 pulley. Radiopaque dye provided contrast to the injection medium, and postinjection x-rays identified the true delivery site of the steroid solution. Of the 52 digits into which intrasheath injection was attempted, 19 digits (37%) received all the injection within the sheath, 24 (46%) received medication into both the sheath and the subcutaneous tissues, and 9 (17%) received no medication within the tendon sheath. The results were analyzed to determine whether injection placement influences the efficacy of steroid injection. The confirmed all-sheath injection group exhibited a 47% good response, the mixed sheath and subcutaneous group had a 50% good response, and the all-subcutaneous group had a 70% good response. The results of this study suggest that true intrasheath injection offers no apparent advantage over subcutaneous injection in the treatment of trigger digits.