Background: The clinical picture of ulnar-sided wrist pain is oftentimes confusing because various pathologies may be coexistent. In this study, we aimed: (1) to compare the prevalence of potential causes of ulnar-sided wrist pain on magnetic resonance imaging (MRI) in patients who underwent triangular fibrocartilage complex (TFCC) repair and control subjects: and (2) to evaluate whether inferior clinical results were associated with specific patient characteristics or other potential causes of ulnar-sided wrist pain. Methods: We included 67 patients who underwent a TFCC repair and 67 control subjects. The MRI scans were examined for sources of ulnar-sided wrist pain. After TFCC repair, 42 patients (63%) completed surveys, including Quick Disabilities of the Arm, Shoulder and Hand and pain scores. Bivariate analysis was performed to compare our groups and to identify factors associated with our outcomes. Results: We found significantly higher rates of distal radioulnar joint (DRUJ) arthritis (P =.033), extensor carpi ulnaris (ECU) pathology (P =.028), and ulnar styloid fractures (P =.028) in patients with TFCC repairs. With increasing age, increasing pathology in the pisotriquetral joint (P =.040), more ulnocarpal abutment (P =.0081), and more degenerative tears (P <.001) were seen in both groups. No demographic characteristics or MRI findings were significantly associated with our outcomes. Conclusions: We observed higher rates of DRUJ arthritis and ECU pathology in patients with TFCC tears undergoing repair compared with age- and sex-matched controls. This may be due to damage to the TFCC itself altering relationships of the DRUJ and the ECU subsheath, or it may reflect various pathologies that cause ulnar-sided wrist pain and drive patients toward surgery.