Abstract
Aims: To compare the femoral stem position and alignment, using different methods of insertion. The Exeter stem has been compared with a new tri-tapered, polished, cannulated, cemented, femoral component.
Method: We have reviewed 100 post operative AP and 50 lateral radiographs for each group. Analysis determined both stem tip position and stem alignment. The groups of subjects were of comparable age, sex and Body Mass Index.
Results: Values for mean distance from canal centre were calculated, for the Exeter group this was 1.511 ± 1.226 and Tri-Taper group 0.778 ±. 0.748. This was statistically signiþcant (p=0.0059). In our Exeter series of results we have shown that 71% of stem tips had been inserted within 2mm of central, this compares with 94% in the Tri-Taper series. On the lateral radiographs of the Exeter series the mean posterior distance was 2.245 ± 1.316, the mean anterior distance was 1.068 ± 0.528. In the Tri-Taper series the mean posterior distance was 1.123 ± 0.926, the mean anterior distance was 1.057 ± 0.590. The difference between the two groups was not statistically signiþcant (p=0.054). The alignment results show that only 78% of stems are aligned neutrally compared with 91% of tri-taper stems (p= 0.0454).
Conclusion: These results are comparable with previous cannulated and Exeter stem studies. This conþrms that optimal distal stem position and stem alignment can be achieved by using a cannulated stem rather than the application of a distal centralising device.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
