Numerical simulation of reduction strain in cortical bone by manipulation reduction frame

The problem and the task formulation

The process of distraction elongation of tubular bones is a complicated phenomenon that has been little studied; most studies in this field have been empirical by their nature and the operating surgeon used exclusively his own experience, being unable to predict the behavior of the bone and biomechanical processes in the bones of an individual patient.

Our client is one of the European leading Institutions of Traumatology and Orthopedics. We cooperated for the development of the method of numerical modeling of strain reduction in cortical bone by manipulation reduction frame.

Problem-solving technique

When we developed the methodology, the client provided to us the cross section of cortical bone made using tomograph, the general diagram of the automatic distraction machine, the description of its typical operation conditions and the general scheme for the machine placing on the bone.

Then our specialists made a 3d model of the bone, a 3d model of the parts and assemblies of the automatic distraction machine, and a 3D mathematical model �machine-bone�.

The use of our innovative scenario-analysis methods allowed making the required number of calculation scenarios that completely described behavior of the system �machine-bone� during automatic distraction.

During analysis we made effective use of FE method; all procedures were performed under CAD/CAE/PDM by EDS Company. Our research allowed determining the picture of tension and deformation conditions of the bone with two versions of spike arrangement.

Comparative analysis of stress and tension demonstrated that stress varied depending on the spike placement angle. In this case the difference in stress was about two folds.

Results

Cooperating with us, the client received a method for simulation modeling of distractive forces in the tubular bones, which can be used to analyze various spike placement angles and to model versions of support arrangements.

When working independently, specialists of the client who are professionals in this narrow field of expertise were not able to make required research and invent a versatile methodology for numerical simulation of distractive forces.