A parametric approach to construct femur models and their fixation plates

Abstract

Although anatomic plates reflect an important breakthrough in the treatment of distal femur fractures, there are still some patients experiencing healing complications. For individual differences in bone morphology and fractures, the development of patient specific plates is very complex and needs a long cycle. In this study, a parametric approach was proposed to conveniently construct femur models and design their fixation plates. First, the typical femur anatomy was described with the average femur model. Second, five surface features were defined to represent the femur surface model by setting up parameterization and parameter constraints. Third, according to the fracture information of a specific patient, customized plate surface with a suitable contour was created from the reconstructed femur model. Finally, the femur plate was represented by feature parameterization, and the hierarchical constraints between femur parameters and plate parameters were built to construct a plate model. The experimental results showed that the proposed method could effectively represent femur surface shape features and intuitively construct and edit individualized plates with high-level parameters. The method is competitive in time saving and design convenience and may provide a basic tool for digital restoration of incomplete femurs and the design of patient specific femur plates.

Fit assessment of two different anatomically contoured distal femur plate sets on cadaveric bones

“…The development of a patientspecific plate is a very complex and an expensive procedure. [8][9][10] Wang et al [21] evaluated eight anatomical femur parameters in 100 femur samples and designed three sizes of anatomical plates for femur and proposed that one should be selected correspondingly according to femur parameters. In our clinic, we use commercially available unisize plates, which are designed based on mean anthropometric data, and choose the plate lengths according to fracture characteristics such as fracture types and lengths.…”

“…The development of patient specific plates is reported but this is a very complex and an expensive procedure. [8][9][10] The variations in bone morphology may cause poorly fitting plates in some patients and the surgeon can be misled by this mismatch resulting with malalignment unless the surgeon manually contours the plate accordingly. [11] The chances of malunion in distal femur locked plating in inexperienced hands are higher as the reduction of comminuted fractures is difficult.…”

“…mL (range[7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] and the nine-hole plate group was 16.3 mL (range, 8-30 mL). Descriptive statistics for volume measurements are given in…”

Construction of restored model of fractured femurs based on anatomic features

“…Taking a mesh model of fractured bone pre-generated from CT images as input, the approach of constructing restored model of fractured femur (RMFF) included the following steps based on previous research works [23][24][25][26].…”

A Novel Computer-Aided Approach for Parametric Investigation of Custom Design of Fracture Fixation Plates

“…Previously, the authors proposed a parametric method to construct a surface model of a patient's femur based on surface feature parameterization [ 12 ]. It was found that the surface model could be accurately constructed and modified according to the hierarchical feature parameters of a patient's femur [ 13 ].…”