ISOLATED GREATER TROCHANTER FRACTURES: CAN WE PREDICT THE INTERTROCHANTERIC EXTENSION BASED ON PLAIN RADIOGRAPHIC CRITERIA?

Abstract

The knowledge of actual extent of the fracture in cases of isolated greater trochanteric fractures has paramount importance in decision-making. MRI has been the most common investigation to detect the intertrochanteric extension. However, to date there is no plain radiographic or MRI criteria to decide which fractures need surgery and which could be managed non-operatively. The aim of our study-was to assess whether the angle and the extent of the greater trochanteric fracture measured on plain radiographs could be used to predict the intertrochanteric extension.

We reviewed plain radiographs of 23 patients with isolated greater trochanteric fractures who also had MRI scans. We considered two parameters

1. extent of fracture in percentage along the intertrochanteric line and

2. angle of the fracture line. We compared these plain radiographic findings with those of MRI scans and established plain radiographic criteria to predict intertrochanteric extension.

Out of 23 patients, MRI scans revealed intertrochanteric extension in eight and they underwent surgical stabilisation. All these eight fractures had a fracture angle of 45° or less and the percentage of fracture extent of > 40%. All the 15 fractures with a fracture angle of > 45° did not show intertrochanteric extension on MRI scan. The mean angle of the fracture in those with MRI proven intertrochanteric extension was 33.5° (range 20°–45°) and in those with no intertrochanteric extension was 55.7° (Range 25°–125°). The mean percentage of length of fracture across the intertrochanteric line was 61.1% (47%–73%) and 39.6% (27%–62%) respectively.

We conclude that those isolated greater trochanteric fractures, with a fracture angle of more than 45° are unlikely to have an intertrochanteric extension. Those fractures with an extent of more than 40% and fracture angle less than 45° are likely to show inter trochanteric extension.