BACKGROUND: Prone positioning during endoscopic retrograde cholangiopancreatography (ERCP) can lead to post-procedure neck pain due to increased cervical spine stress and prolonged muscle stretching. This study aimed to evaluate the efficacy and satisfaction of an ergonomic wedge pillow for patients undergoing prone ERCP. METHODS: Patients indicated for ERCP were randomized 1:1 to a study group (with the pillow) or a control group. Neck pain was assessed before ERCP and at 1 h, 1 day, and 7 days post-procedure by blinded assessors. Endoscopists rated scope intubation difficulty and satisfaction with the pillow. The need for patient shoulder lifting during intubation was also recorded. RESULTS: A total of 256 patients were randomized to the study group (128 patients), and the control group (128 patients). The baseline characteristics were not different between the two groups. The prevalence of post-procedural neck pain at 1 day was significantly lower in the study group (19%) than the control group (30%) (p = 0.040), especially for moderate-to-severe neck pain (4% vs 11%, respectively) (p = 0.032). The study group had a lower difficulty score of scope intubation and required less shoulder lifting during scope intubation (9% vs 22%, respectively) (p = 0.002). Endoscopists' satisfaction scores were significantly higher in study group than the control group (9.6 vs 8.9, respectively) (p <
0.001). CONCLUSION: An ergonomic wedge pillow for prone ERCP reduced moderate-to-severe pain at day 1 after ERCP, difficulty of scope intubation, and the requirement of shoulder lifting during procedure. Moreover, this ergonomic pillow had a higher endoscopists' satisfaction score than the control group.