Numerical stress analysis of an artificial hip joint using a three dimensional finite element method was made. A three dimensional anatomic model was employed and a convergency test was made by increasing the number of elements to check the accuracy of the model. Also the influence of the stem shape on the distribution of the stress the total hip arthroplasty was studied.
The critical region in the total hip arthroplasty was found to be at the proximal and distal ends in the cement layer where stress concentration is occurred. At the proximal region, desirable stress distribution was resulted from a thicker stem with broad medial and lateral surfaces. At the distal region, the stress level became lower when the stem got thinner.