Stable intertrochanteric femoral fractures. A misnomer?

Intertrochanteric fractures of the femur are usually classified into stable and unstable groups, partly to predict the likelihood of displacement with early weight-bearing after internal fixation. Of 82 internally fixed intertrochanteric fractures which would normally be classified as stable, 25 subsequently underwent impaction along the axis of the nail or screw; varus displacement occurred in another six. Of these 31 fractures, 10 were two-part fractures which had been anatomically reduced, and 12 were originally undisplaced. It did not seem possible to predict the subsequent instability from the pre-operative radiographs. Of the 82 fractures, 47 had been treated with a Jewett nail-plate and 35 by a Richards compression screw-plate. Two groups of stable fractures were recognised: Group 1 was undisplaced and Group 2 displaced. Axial impaction occurred in a quarter of all Group 1 fractures however treated. In Group 2 fractures it occurred in a quarter of those treated with a nail-plate, and in over a third of those treated with a sliding screw-plate. The six fractures that underwent varus displacement had all been treated with Jewett nail-plates. Penetration into the joint occurred in 10 patients, all of them in the group treated with Jewett nail-plates; four required re-operation.