ABSTRACT
In this paper, the complex 3D virtual model of the prosthetic knee is obtained using embedded applications: DesignModeler and SpaceClaim under ANSYS Workbench 14.5 software package. A number of six cases of prosthetic knee joint assembly, depending on the malalignment angle, are developed. Stress maps and the values of the maximum von Mises stress on the three prosthesis components: polyethylene insert, tibial component and femoral component, for all studied prosthetic knee assemblies were obtained. The results show that as the malalignment angle increases, the values of von Mises stresses increase in all prosthesis components. The parameterized virtual models of the knee prosthesis components allow different changes in shape or dimensions, which can lead to the optimization of the implant and to the improvement of the prosthetic knee biomechanics.
Subject(s)
Finite Element Analysis/statistics & numerical data , Imaging, Three-Dimensional/methods , Knee Joint/surgery , Knee Prosthesis/adverse effects , Biomechanical Phenomena , Humans , Stress, MechanicalABSTRACT
The Achilles tendon is the widest tendon of the human body. Achilles tendon belongs to the extrasynovial tendons group and this allows it a faster recovery, thanks to local hematoma from the peritenon, necessary for the scarification. We concluded that in Achilles tendon rupture treatment it is essential to maintain the tendon covering skin integrity, the peritendinous integrity, to maintain the local hematoma formed during and after tendon rupture, reattaching the ruptured tendon heads and maintain them in this position by suturing them and by relaxing the sural triceps muscle. The percutaneous suture requires five pairs of mirror micro-incisions (5 mm) on one side and the other of the tendon. It is necessary for one of the pairs to be placed to the rupture level. With a surgical needle, we arm the proximal and distal heads of the tendon by different threads. By traction and muscular relaxation, we bring in contact the two ruptured heads and then we knot together the arming threads. The inferior member was cast immobilized in relaxing position for the sural triceps muscle for a 45 days period. Using this technique, we have operated 15 cases in our Clinic. In all the cases, we obtained a healing by first intention of the tegument micro-incisions. After the cast immobilization suppression, during 30 days the patients were in a recovery program. At the end of this program, they have recovered completely the dorsal and plantar flexion and the walking. In four months after the surgery, the esthetic of the area is completely restored, this technique being the only surgical technique that realizes this recovery.
