Computer-aided design and simulated-mechanical study of custom-made femoral prosthesis

Shuqiang LI; Dongsong LI; Xin QI; Tao JIANG; Jianguo LIU

ABSTRACT

BACKGROUND:

Standard artificial prosthesis does not well match to patients' skeleton due to absolute individuation,while the difference between them does not keep the stabilization of artificial joint for a long term.

OBJECTIVE:

To construct three-dimensional models of custom-made femoral prosthesis by using computer-aided design and to verify whether custom-made femoral prosthesis is superior to popular femoral prosthesis via simulating and contrasting mechanical study.DESIGN,TIME AND

SETTING:

Opening study was performed in the Orthopaedics Institute of the First Clinical Hospital and the Biomechanics Institute,Jilin University between September 2006 and May 2007.MATERIALSOne fresh femur was derived from adult corps.

METHODS:

Two-dimensional images of the fresh femur was obtained by using total-length CT scanning and processed with computer edge recognition and three-dimensional contour extraction software to identify outer and inner contour of bone cavity,extract contour data of bone cavity and prosthesis,and construct three-dimensional models of femur and custom-rhade femoral prosthesis.SolidWorks software was used to establish three-dimensional prosthetic models in common biological and bone cement types; moreover,bone-cement,biological,and custom-made femoral prosthesis were replaced via simulating clinical surgery.MAIN OUTCOME

MEASURES:

Standing on single or double feet was simulated to measure stress distribution,interface stress,and primary micromotion of femoral prosthesis in the three types.

RESULTS:

Edge extracting was replaced by Canny calculator,characterizing by stable running,credible outcome,and consistent with the primary request.Stress,femoral stress,interface stress,and primary micromotion of custom-made femoral prosthesis were significantly lower than biological and'bone-cement femoral prosthesis (P ＜ 0.01).

CONCLUSION:

The computer-aided design is reliable to perform the assistant design of prosthesis; furthermore,biomechanical properties of the custom-made femoral prosthesis are superior to those of popular femoral prosthesis.