The digital measurements for femoral prosthesis in a Turkish population

Abstract

Objectives: This study was designed (i) to evaluate the angle between anatomical and mechanical axes of the femur and (ii) to compare shaft curve of the femur according to anatomical axis of femur with curve of the four femoral nail used in a Turkish population, in order to determine the safety degrees of distal femoral valgus cut for a routine surgical procedures.

Methods: Sixty-six right femurs, 68 left femurs and 4 femoral nails were measured. We measured the angle between anatomical axis and mechanical axis, the shaft curve of the femur according to anatomical axis on the femurs and shaft curve of the femoral nail on 4 femoral nails, which are commonly used in Turkey, using a digitizer system.

Results: In the 66 right femurs, the mean values of the angle between anatomical axis and mechanical axis was calculated as 6.386±0.820º and the mean value of the shaft curve of the femur according to anatomical axis was calculated as 16.713±2.371º. In the 68 left femurs, the mean value of angle between anatomical axis and mechanical axis was calculated as 6.915±0.712º and the mean value of the shaft curve of the femur according to anatomical axis was calculated as 16.148±2.689º. We calculated that curve of the 4 nails were Hipokrat 8.65º, Trigen 10.20º, Ortopro 6.38º and Recon 8.70º, respectively.

Conclusion: According to our results, new nails should be designed in the light of anatomical studies for each population. This will reduce the complications during surgery.

Keywords

• anatomical axes
• cutting guide
• femoral curve
• femoral nail
• mechanical axes

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