Description of new "epsilon sign" and its significance in reduction in highly unstable variant of intertrochanteric fracture.

Abstract

Intertrochanteric fractures are commonly encountered in day-to-day trauma practice having various fracture patterns. Adequate reduction and appropriate fixation methodology is required for optimum results. However, failure rates are very high in unstable fractures. Here we describe a unique unstable variant of intertrochanteric fracture characterized by a long spike of proximal fragment, irreducibility of fracture with standard traction and internal rotation and soft tissue interposition. This appears as typical figure of 3 signs on right side and epsilon ε sign on left side on AP X-ray of pelvis with both hips. In retrospective review of 924 intertrochanteric fractures treated at our institution from June 2005 to January 2017, twenty patients with this typical highly unstable fracture pattern (epsilon sign/figure of 3 at fracture site) were operated at our institution, which included 18 males and two females with average age of 43.5 years (range 30-60 years). All patients required open reduction with specific maneuver and dynamic hip screw fixation. All patients had good reduction at the end of surgery, and all patients had good signs of clinico-radiological union at follow-up. None of the patients had implant loosening or screw back out. The typical radiological pattern seen on X-ray will guide the surgeon to predict this unstable variant of IT fracture preoperatively and will suggest toward requirement of open reduction with specific maneuver and internal fixation with dynamic hip screw.