Open reduction and internal fixation of displaced head-split type humeral fractures and role of the rotator-interval approach.

Background: Open reduction and internal fixation (ORIF) of humeral head split fractures is challenging because of high instability and limited visibility. The aim of this retrospective study was to investigate the extend of the approach through the rotator interval (RI) on the reduction quality and functional outcome. Methods: 37 patients (mean age: 59  ±  16 years,16 female) treated by ORIF through a standard deltopectoral (DP) approach were evaluated. The follow-up period was at least two years. In 17 cases, the approach was extended through the RI. Evaluation was based on radiographs, Constant scores (CS) and DASH scores. Results: In group DP, "anatomic" reduction was achieved in 9 cases (45%), "acceptable" in 5 cases (25%), and "malreduced" in 6 cases (30%). In group RI, "anatomic" reduction was seen in 12 cases (71%), "acceptable" in 5 cases (29%), and "malreduced" in none (p  =  0.04). In the DP group, the CS was 60.2  ±  16.2 and the %CS was 63.9  ±  22.3, while in the RI group, the CS was 74.5  ±  17.4 and the %CS was 79.1  ±  24.1 (p  =  0.07, p  =  0.08). DASH score was 22.8  ±  19.5 in DP compared to RI: 25.2  ±  20.6 (p  =  0.53). Conclusions: The RI approach improves visualization as it enhances quality of fracture reduction, however functional outcomes may not differ significantly. Type of study and level of proof: Retrospective, level III.