Different arthroscopic techniques exist for managing the exterior carpi radials brevis (ECRB) when treating refractory lateral epicondylitis. The purpose of this study is to compare the outcomes of a standard arthroscopic débridement with ECRB tendon release to an arthroscopic ECRB tenotomy distal to its insertion without débridement using a retrospective cohort study design. This study included patients underwent arthroscopic treatment of lateral epicondylitis during 2 different time periods: 2016 to 2019 (débridement) and 2019 to 2021 (modified tenotomy without débridement). Patients were assessed preoperatively and at the last follow-up with mayo elbow performance score (MEPS), disabilities of the arm, shoulder and hand (DASH) score, visual analog scale (VAS) of pain. A total of 69 patients completed the follow-up (38 in the débridement group and 31 in the tenotomy group). Patients in both groups showed significant improvements were found in MEPS, DASH, and VAS after surgery. Patients in the tenotomy group had higher MEPSs and reported less pain with a minimum 2 year follow-up after surgery. DASH scores between groups were similar at all time periods. Arthroscopic modified tenotomy of the ECRB without débridement improves function and pain significantly for patients with refractory lateral epicondylitis, which is not inferior to arthroscopic débridement technique.