Is subcutaneous local anesthesia in shoulder magnetic resonance arthrography necessary?

Background: Magnetic resonance arthrography is a well- established diagnostic method in degenerative and traumatic disorders of the shoulder. Some radiologists prefer to apply a local anesthetic to the skin prior to performing the joint puncture. However, no information regarding the efficacy of local anesthetics exists. Purpose: To assess patient discomfort in arthrography injection. Material and Methods: A patient survey ( n=74) utilizing a visual analog scale ( VAS) measured the intensity of pain in arthrography injection by those receiving local anesthetics ( n=36) versus those who did not ( n=38). Results: Mean VAS scores were 20.8 ( median 10.5, SD 24.3) for those receiving local anesthetics versus 19.3 ( median 13.0, SD 20.7) for those who did not ( P=0.83, Mann-Whitney U test). Conclusion: Routine use of local anesthesia of the skin in arthrography injection is unnecessary.