Comparison of fixation techniques in Vancouver type AG periprosthetic femoral fracture: a biomechanical study.

OBJECTIVE

The purpose of this study was to biomechanically compare cable, trochanteric grip plate, and locking plate techniques in Vancouver type AG fracture model in an in vitro test environment.

METHODS

Fifteen pieces of fourth-generation synthetic femora were separated into 3 groups of 5 models each. A greater trochanteric fracture model was created after femoral stem implantation. Group 1 was fixated with only cable, Group 2 with trochanteric grip plate, and Group 3 with locking plate. Horizontal stiffness, axial stiffness, and failure loads were compared between the groups.

RESULTS

In horizontal compression tests, Group 3 had the highest values, but the only statistically significant difference was between the locking plate group and cable group. Axial distraction test results showed that mean stiffness of Group 1 was 94.6±9.44 N/mm, that of Group 2 was 174.8±28.64 N/mm, and that of Group 3 was 185.6±71.64 N/mm. While locking plate versus cable fixation and grip plate fixation versus cable fixation showed statistically significant differences (p<0.05), comparison of locking plate versus grip plate fixation showed no statistically significant difference (p>0.05). In axial failure load test, Group 3 had the highest results. The only significant difference was between the locking plate and cable groups (p<0.05).

CONCLUSION

In Vancouver type AG fractures stable fixation may be achieved with grip plate fixation and locking plates, with the former ensuring more stable osteosynthesis.