Appendix

Does the fracture of the lateral wall affect the degree of collapse and the degree of sliding of the cephalic plate, in pertrochanteric fractures treated by intramedullary interlocking? Radiological study and review of the literature

BACKGROUND

Lateral wall fracture has been recognized as an important sign of instability of pertrochanteric fractures. The aim of the present study is to assess the relationship between lateral wall fractures, helical blade telescoping and neck shortening in fractures treated with intramedullary nailing.

MATERIAL AND METHOD

A descriptive radiological study was performed at our institution. Patients who suffered a pertrochanteric fracture, treated at Hospital 12 de Octubre by intramedullary nailing were included. All fractures were classified according to Evans and AO systems. Preoperative and postoperative radiological assessment was carried out including a lateral wall fracture classification, helical blade telescoping and femoral neck shortening.

RESULTS

210 patients were included, 48% had a fracture of the femoral lateral wall. Helical blade telescoping was higher in lower lateral wall fractures with respect to higher fractures. Difference was statistically significant (p<0.05). Neck shortening was higher in fractures with femoral lateral wall disruption; despite not have found any significant differences comparing to fractures with intact lateral wall (P=.39). Multivariate analysis showed statistically significant association between helical blade telescoping, neck shortening and lateral wall fracture.

CONCLUSIONS

There is evidence of a higher helical blade telescoping and neck shortening in pertrochanteric fractures with lateral wall fracture treated with intramedullary nails, especially in those with most unstable patterns such us fractures of the lateral wall distal to the vastus ridge.