The Design Of Artificial Femoral Articulation And The Primary Research Of 3-demention Modeling Of It

Objective To design a new type of artificial femoral head, which had the special function of adjustable anteversion angle and preventing prosthesis settlement.To directly demonstrate this new design concept of the artificial femoral head, by establishing three-dimensional dynamic image with computer software.Method(1) By utilization of AutoCAD software, two-dimensional drawings of artificial femoral head prosthesis were obtained, the whole design drawing of artificial femoral head included three parts—femoral head, femoral neck, femoral stem .①shape,size,diameter of prosthesis head②shape,diameter,length of prosthesis neck; shape, size, depth of the middle cervical tooth outside prosthesis③shape, length of prosthesis stem. Prosthesis prosthesis stem included: a. hydroxyapatite (Hydroxya -patite, HA) coating;,range of coating,the thickness; b. three locking hole channel in prosthesis stem; diameter, distance, length of locking hole channel; c. shape, size, depth of annular gear of the basilar part of femoral stem ;④the structure of prosthesis neck connecting stem with internal and external gear.(2)The model was established by using software 3DMAX 8.0, according to the data of artificial femoral head data, provided by Turbo Squid company. The form and fidelity of model were Observated.Results(1)According to design requirements and design concepts, the artificial femoral head was drawn out by software AutoCAD; the whole artificial femoral head was composed of three parts—the femoral head, femoral neck, femoral stem is composed;①Prosthesis head was a circular, the diameter was 26～28 mm.②Prosthesis neck was conical, the diameter was 10～15 mm,the length was 50-70mm, the gear in the middle of neck was external gear.the diameter was 10～15 mm, the length was 10-15mm, the external tooth was ladder, the length of superior margin of the tooth was 0.9mm, the length of lower margin was 1.4mm, the depth was 2mm. ③Proximal prosthesis stem was biconical, the length was 130-140mm, including : a. one-third of HA coatings on prosthesis stem, thickness was 5mm ; b. diameter of three channel Lock hole was 5mm, the distance between channel Lock hole and handle seat, from near to far, was 40mm, 75mm, 105mm, the length of the corresponding channel pore was 40mm, 20mm, 10mm ; c. the gear at the basilar part of femoral stem was internal gear , there was a dial on the internal gear, the diameter was 10-15mm, the length was 10-15mm, the shape of internal tooth was ladder, the length of superior margin of the tooth was 1.0mm, the length of lower margin was 1.5mm, the depth was 2mm.④Within a scale of the gear rotating, the anteversion angle had 2°change.(2)The three dimensional model of the artificial femoral head was created, and its form and fidelity meets the design requirements.Conclusion:(1)The artificial femoral head with a special functional, can be designed by using software AutoCAD, according to the requirement of designer.(2)The figure of the new type of artificial femoral head, established by using software 3DMAX 8.0, whose integrative construction,partial design is clear, can be demonstrated individually,combinely dynami -cally.(3)The new type of artificial femoral head, demonstrated by three-dimensional animation, meets the design requirements and provides important basis for futher research of this type.