Motion parameters analysis and pilot clinical trials of the dual mobility hemi-knee artificial prosthesis / 中华骨科杂志

ABSTRACT

ObjectiveAim at the problems in the treatments of the children malignant bone tumor of distal femur,we put forward the concept of the dual mobility hemi-knee prosthesis and try to perform the motion parameters analysis and the pilot clinical trials.MethodsBase on the CT data from samples of knee joint in adult,we adopted the Mimics/Geomagic/Pro-E software and computer numerical control milling machine technology to design and produce the dual mobility hemi-knee artificial prosthesis,and then motion parameters was analyzed in vitro test,and at last pilot clinical trial was performed.ResultsIn vitro experiment showed that the displacement of the internal femoral condyle flexion facet center was(2.59±0.43) mm in normal knee group,(2.22±0.52) mm in dual mobility hemi-knee prosthesis group,and (1.18±0.43) mm in total knee arthroplasty group; the displacement of the external femoral condyle flexion facet center was (11.95±6.62) mm in normal group,(11.25±6.19) mm in dual mobility hemi-knee prosthesis group,and (1.26±0.42) mm in total knee arthroplasty group; the maximum relative rotation angle was 13.17°±7.58° in normal knee group,11.69°±6.49° in dual mobility hemi-knee prosthesis group,and 5.40°±1.29° in total knee arthroplasty group.After that,we accomplished the pilot clinical trials successfully for a patient with malignant bone tumor in distal femur.The patient recovered well and the treatment outcome was satisfactory.ConclusionThe motion parameters analysis showed that the motion mode of the dual mobility hemi-knee prosthesis is similar with that of the normal knee.The dual mobility hemi-knee prosthesis provides a whole new concept and method for the treatment of malignant bone tumor of distal femur in children,and the device and concept of ligament reattachment provide a solution to the reconstruction of knee ligament.