Femoral neck collapse after internal fixation of an intracapsular hip fracture: Does it indicate a poor outcome?

The degree of femoral neck collapse that occurred after 519 patients with an intracapsular hip fracture treated by internal fixation with a Targon FN implant was measured. Mean femoral neck collapse was 8.0 mm and this was increased for displaced fractures in comparison to undisplaced fractures (9.5 mm versus 5.9 mm, p < 0.0001) and for those patients that subsequently developed fracture healing complications (11.6 mm versus 7.1 mm, p < 0.0001). At one year from injury femoral neck collapse in excess of 15 mm was associated with an increase in the degree of residual pain (p = 0.01). A clear relationship between increased collapse and increased loss of mobility was demonstrated (P < 0.0001). This study confirms previous smaller studies that excessive femoral neck collapse (of more than 15 mm) is more common for displaced fractures and presents new data to demonstrate that excessive femoral neck collapse is associated with an increased risk of fracture healing complications and increased loss of function. Future studies are now justified that consider methods to reduce fracture collapse.