A comparison of 90° and 180° plate constructions for cominuted distal humerus fractures in adults and effects on clinical results

BACKGROUND: The present objective was to compare 90° and 180° double-plate constructions for complex distal humerus fractures, as well as to evaluate superiority of construction type. METHODS: Retrospectively evaluated were 17 patients treated for type C distal humerus fracture according to AO/ASIF classification between January 2009 and January 2013. All attended minimum 6-month follow-up. Elbow function was assessed with anteroposterior and lateral x-ray, and Mayo elbow performance score evaluation at outpatient clinics. RESULTS: Patient population included 14 males (82.3%) and 3 females (17.7%). Mean patient age was 40.5 years. According to AO/ASIF distal humerus classification, 3 (17.7%) type C1, 9 (52.9%) type C2, and 5 (29.4%) type C3 fractures were included. Six were open fractures (35.3%). According to Gustilo-Anderson classification, 4 (23.5%) fractures were type 1, and 2 (11.7%) were type 2. Construction performed was 90° in 11 cases (64.7%) and 180° in 6 cases (36.3%). Chevron osteotomy was performed in all cases. Mean follow-up period was 25.6 (6-52) months. Upon final examination, mean elbow flexion was 105º (85º-130º), and mean extension loss was 10º (0º-20º). According to Mayo elbow performance scoring system, 12 (70.5%) results were excellent, and 5 (29.5%) were good. No statistically significant clinical difference was found between 90° and 180° plate construction groups (p=0.169). DISCUSSION: Surgeons should determine the construction type appropriate to individual cases of adult distal humerus type C fractures using preoperative x-rays and intraoperative means. Choice of construction type has particular importance in cases of lateral columnar fracture complexity. If no comminution is present in the lateral column, 90º double-plating leads to satisfactory outcome, while 180º plating leads to satisfactory outcome when comminution is present in the lateral column.