Corticosteroid injection in patients with ulnar neuropathy at the elbow: A randomized, double-blind, placebo-controlled trial.

INTRODUCTION: We conducted a randomized, double-blind, placebo-controlled trial to evaluate the effect of ultrasound-guided corticosteroid injection in patients with ulnar neuropathy at the elbow (UNE). METHODS: Fifty-five patients were randomized between an ultrasound-guided injection of 1 ml containing 40 mg methylprednisolone acetate and 10 mg lidocaine hydrochloride or a placebo injection. The primary outcome was the subjective change of symptoms after 3 months. The secondary outcomes were change in electrodiagnostic studies and ultrasonography findings. RESULTS: A success rate of 30% was found in the corticosteroid injection group versus 28% in the placebo injection group. Only the nerve cross-sectional area changed significantly in the intervention group, from a mean of 11.9 mm(2) to 10.9 mm(2) . CONCLUSIONS: We could not demonstrate a positive effect of ultrasound-guided corticosteroid injection in UNE compared with placebo. Favorable outcomes may be attributed to the natural course of UNE or the effect of patient education.