Abstract
Objectives
Our principle is to bring the socket back to the true acetabulum position. A large structural bone graft is required for severe subluxation. We obtained good long-term results with structural bone grafts. It is necessary to evaluate the bone graft 3 dimensionally, not 2 dimensionally.
M and M
We evaluated our 305 primary THAs operated from April 2010 to Mar 2014. Structural bone grafts were utilized on the acetabulum in 39 cases (12.8%).
We measured the CE angle on post-operative plain coronal x-rays. 3D-CT evaluation was carried out on the cases with CE angles of 0 degrees or less.
We checked the position of the graft and see how much surface area the graft occupies of the total area that receives the load.
Result
Mean CE angle on the post-op plain coronal x-rays was −1.5°. 15 cases (38.5%) had 0 degree or less CE angles on the post-op plain coronal x-rays. 11 cases (−15°≤CE<0°), and 4 cases (−30°≤CE<−15°). Mean CE angle was +3.7° on coronal CT of the apex of the socket. Graft position on the acetabulum on 3D-CT was anterosuperior in 13 cases and posterosuperior in 2 cases, wile none showed wide positioning from anterosuperior to posterior.
Conclusion
The contact surface area between the graft and the socket is not necessarily large 3 dimensionally, even if the CE angle is 0 degrees in the plain coronal X-rays. Depending on the graft position, sufficient support is considered to be obtained, even though a large size graft is used.
