Pertrochanteric fractures (AO/OTA 31-A1 and A2) not amenable to closed reduction: Causes of irreducibility

Abstract

PurposeTo define the unique radiographic features, operative treatment, and complications of pertrochanteric fractures (AO/OTA 31-A1 and A2) which are not amenable to the usual closed reduction manoeuvres. MethodsDuring a 2-year period (from August 2011 until December 2013), 212 patients with pertrochanteric fractures were treated at our level I trauma centre. A retrospective review was undertaken to determine which of these fractures were not reducible via the routine closed reduction manoeuvres and required some form of open reduction. These fractures were assessed for radiographic markers of irreducibility, surgical findings, reduction techniques, and perioperative complications. ResultsTwenty-four patients had fractures, which were not amenable to closed reduction and underwent open reduction. These fractures could be grouped into four patterns. A preoperative CT scan was available for at least two cases of each pattern, which provided further insights into the cause of irreducibility by closed means. These included a variant where the proximal fragment is locked underneath the shaft fragment (3 cases), bisected lesser trochanter with a locked proximal fragment (3 cases), irreducibility due to entrapped posteromedial fragment at the fracture site (6 cases) and a variant where the proximal fragment is flexed passively by the underlying lesser trochanter (12 cases). ConclusionsPertrochanteric fractures, which are not amenable to closed reduction, are uncommon, but are heralded by unique radiographic features. These patients warrant special consideration in terms of recognition and management. The specific radiographic markers should alert the surgeon to this injury pattern and its related difficulty encountered during closed reduction. Once reduction is achieved, however, these fractures follow an uneventful course.