Wrist pain on the ulnar side is often caused by ulnar impaction syndrome (UIS). Idiopathic UIS requires surgical treatment when conservative treatment fails. The 2 main surgical procedures used are the wafer procedure and ulnar shortening osteotomy (USO) of the metaphysis or diaphysis. This review aimed to analyze comparative studies of the 2 procedures in UIS to determine clinical outcomes and complications./r/nOne prospective and 5 retrospective comparison trials were retrieved from the PubMed, Embase, and Cochrane Library databases. The primary outcomes were treatment effectiveness; pain visual analog scale (VAS), disabilities of the arm, shoulder, and hand (DASH) score, Mayo wrist, and Darrow scores. The incidence of postoperative complications formed the secondary outcome./r/nThe selected studies included 107 patients who underwent the wafer procedure (G1) and 117 patients who underwent USO (G2). The wafer procedure had the benefits of less postoperative immobilization and an early return to work. However, there were no significant differences in the postoperative pain improvement and functional scores. All 6 studies reported high total complication rates and reoperation with USO. The most frequent complication was implant-related discomfort or irritation; subsequent plate removal was the most common reason for a secondary operation./r/nThere was no difference in pain improvement or the postoperative functional score between the groups. Nevertheless, postoperative complications were the major pitfalls of USO. As the specialized shortening system advances further, a high-level study will be necessary to determine the surgical option in UIS.