BACKGROUND: Semiconstrained total elbow arthroplasty (TEA) is an established treatment for elderly patients with distal humeral fractures not amenable to stable internal fixation (unreconstructable). In recent years, there has been increasing interest in elbow hemiarthroplasty (EHA), a treatment option which does not entail restrictions on weight-bearing as opposed to TEA. These 2 treatments have not been compared in a randomized controlled trial (RCT). The aim of this study was to compare the functional outcome of EHA and TEA for the treatment of unreconstructable distal humeral fractures in elderly patients. MATERIAL AND METHODS: This was a multicenter randomized controlled trial (RCT). Patients were included between January 2011 and November 2019 at one of 3 participating hospitals. The inclusion criteria were an unreconstructable distal humeral fracture, age ≥60 years and independent living. The final follow-up took place after ≥2 years. The primary outcome measure was the Disabilities of the Arm, Shoulder, and Hand (DASH) score. Secondary outcome measures were the Mayo Elbow Performance Score (MEPS), the EQ-5D index, range of motion (flexion, extension, pronation, and supination) and grip strength. RESULTS: Forty patients were randomized to TEA (n = 20) and EHA (n = 20). Five patients died before completing the final follow-up, leaving 18 EHA and 17 TEA patients for analysis. There were 31 women. The mean age was 74.0 (SD, 8.5) years in the EHA group and 76.9 (SD, 7.6) in the TEA group (P = .30). The mean DASH score was 21.6 points in the EHA group and 27.2 in the TEA group (P = .39), a difference of -5.6 points (95% CI: -18.6 to 7.5). There were no differences between treatment with EHA and TEA for the mean values of the MEPS (85.0 vs. 88.2, P = .59), EQ-5D index (0.92 vs. 0.86, P = .13), extension (29° vs. 29°, P = .98), flexion (126° vs. 136°, P = .05), arc of flexion-extension (97° vs. 107°, P = .25), supination (81° vs. 75°, P = .13), pronation (78° vs. 74°, P = .16) or grip strength (17.5 kg vs. 17.2 kg, P = .89). There were 6 adverse events in each treatment group. CONCLUSION: In this RCT, both elbow hemiarthroplasty (EHA) and total elbow arthroplasty (TEA) resulted in a good and similar functional outcome for unreconstructable distal humeral fractures in elderly patients at a minimum of 2 years of follow-up.