Morphology-Guided Approach Selection for AO/OTA 13-C3 Distal Humeral Fractures: A Comparative Study of the Flip-Triceps Dislocation Approach versus Olecranon Osteotomy

<title>Abstract</title> <p>Background The optimal surgical approach for AO/OTA 13-C3 distal humeral fractures remains debated. This study compared the flip-triceps dislocation (FTD) approach with the olecranon osteotomy (OO) approach and evaluated whether fracture morphology (PAD-type vs. non-PAD-type) influences the outcomes of each approach. Methods Thirty-seven patients with AO/OTA 13-C3 distal humeral fractures were retrospectively reviewed, including 18 treated with OO and 19 with FTD. Fractures were classified as PAD-type (n = 20) or non-PAD-type (n = 17) based on preoperative three-dimensional CT. Operative time, intraoperative blood loss, flexion-extension arc, extension deficit, MEPS, DASH score, and elbow stiffness were compared between groups and subgroups. Results The FTD group had significantly shorter operative time and lower blood loss than the OO group (P &lt; 0.001). At final follow-up, overall flexion–extension arc, extension deficit, MEPS, and DASH scores were comparable between groups. In PAD-type fractures, the FTD group achieved significantly lower extension deficit than the OO group (4.8 ± 3.2° vs. 10.2 ± 5.4°, P = 0.018), whereas no difference was observed in non-PAD-type fractures. Conclusion The FTD approach reduces surgical trauma compared with OO while achieving comparable overall functional outcomes. In PAD-type fractures, FTD was associated with superior terminal extension, suggesting that fracture morphology may inform surgical approach selection. Level of evidence III, retrospective study.</p>