Arc Centre Distance Change after Treatment of Complex Transverse Olecranon Fractures with a Large Impacted Articular Fragment Treated with Tension Band Wiring and Bone Graft

Background: The treatment of complex transverse olecranon fractures (CTOFs), also known as olecranon fractures with the impacted articular fragments (IAF), was reported recently. We fix IAFs with absorbable pins supported by autologous bone graft followed by olecranon fracture fixation. We have used the arc centre distance (ACD) method to evaluate the congruency of this concentric hinge joint. The aim of this study is to present the outcomes of this fixation technique and evaluate the value of the ACD method. Methods: We reviewed 26 cases of CTOF treated at our hospital from 2014 to 2020. The functional outcome and range of motion of the elbow joint was measured by MEPS (Mayo Elbow Performance Score). We measured the ACD of each fragment of the ulnotrochlear joint [coronoid process (CP), IAF and olecranon process (OP)] with the CT image taken at 15 months postoperatively on average. Results: The mean arc of elbow motion was 3 degrees to 132 degrees. The mean MEPS at 1 year postoperatively was 94, and 25 of 26 cases (96%) achieved a good or excellent outcome. Twelve patients, who took the elbow CT at least more than 3 months post-operatively, were included for ACD measurement. The postoperative joint incongruency of each fragment was as follows, 0.39 +/- 0.70, 0.40 +/- 0.69 and 0.29 +/- 0.72 mm (CP, IAF and OR respectively) according to the ACD method. The ACD value for each fragment was significantly different before and after the surgery (p < 0.05). Conclusions: Accurate reduction of IAF with absorbable pins completed by tension band wiring with autogenous bone grafting can be an effective technique for CTOF with a large IAE. The restoration of the joint improved ACD.