['To investigate rates, trends, and complications for carpal tunnel release (CTR) related to fellowship training using the American Board of Orthopaedic Surgery Part II Database.', 'We searched the American Board of Orthopaedic Surgery database for patients with carpal tunnel syndrome who underwent either open carpal tunnel release (OCTR) or endoscopic (ECTR) from 2003 to 2013. Cases with multiple treatment codes were excluded. Data were gathered on geographic location, fellowship, and surgical outcomes. Data were then divided into 2 cohorts: hand fellowship trained versus non-hand fellowship trained. We performed analysis with chi-square tests of independence and for trend.', 'Overall, 12.4% of all CTRs were done endoscopically. Hand fellowship-trained orthopedists performed about 4.5 times the number of ECTR than did non-hand fellowship-trained surgeons. An increasing trend over time of ECTR was seen only among the hand fellowship cohort. The northwest region of the United States had the highest incidence (23.1%) of ECTR, and the Southwest the lowest incidence (5.9%). The complication incidence associated with CTR overall was 3.6%, without a significant difference between ECTR and OCTR. Within the hand fellowship cohort the complication incidence for ECTR was significantly less than for OCTR. There was no difference in overall complication rates with ECTR and OCTR between the 2 cohorts. Wound complications were higher with OCTR (1.2% vs 0.25%) and nerve palsy with ECTR (0.66% vs 0.27%); with postoperative pain equivalent between techniques independent of fellowship training.'] Do effects of Hand Fellowship Training on Rates of Endoscopic and Open Carpal Tunnel Release?