Spiral-medial butterfly fractures (AO-12-B1) in distal diaphysis of humerus with rotational forces: preliminary results of open reduction and plate-screw fixation.

OBJECTIVE Humerus shaft fractures are frequent injuries in orthopedic practice and generally occurs with direct and indirect traumas. While the most of these fractures can be managed with conservative methods, in some situations surgery is needed. The aim of this study is to define a different mechanism and treatment result of  humerus spiral fractures with medial butterfly fragment (AO-12-B1). PATIENTS AND METHODS Between 2010 and 2013, 11 patients who had undergone surgery for spiral humerus shaft fracture with medial large butterfly fragment (AO type 12-B1) resulting from a motor vehicle accident were enrolled to the study. All data was retrieved from the hospital's database retrospectively. All fractures were closed type and all of the patients were treated with open reduction and plate osteosynthesis through lateral approach. Elbow and shoulder ROMs were examined for functional outcomes. The DASH (Disabilities of the Arm, Shoulder and Hand) scoring system was applied at the final follow-up visit. RESULTS There were 7 male and 4 female patients with a mean age of 36 years (range, 28-50 years). All of the fractures occurred with same mechanism resulting from motor vehicle accident. Conservative treatment was not considered for any of the cases. The mean time to surgery was 2 days (1-3 days). The mean postoperative follow-up period was 14 months (6-24 months). All fractures had healed completely at 3 months postoperatively. At the final follow-up visit the mean DASH score was 4.2 (3.3-6.7). CONCLUSIONS Humerus spiral shaft fractures with a large medial butterfly fragment can be seen in dashboard injuries. It is important to fix the medial large fragment anatomically and minimal invasively in order to achieve union and not to disturb the vascular supply.