After hip replacement, hip prosthesis zones are regions in the interface between prosthesis material and the surrounding bone. These are used as reference regions when describing for example complications including hip prosthesis loosening on medical imaging. Postoperative controls after hip replacement surgery is routinely done by projectional radiography in anteroposterior and lateral views.
The DeLee and Charnley system applies to the acetabular cup on anteroposterior radiographs. It divides the acetabulum into three equally large zones.[1]
The Gruen zones is a system of dividing the interface between the bone and the stem of the hip prosthesis.
| Zone | Description | |
|---|---|---|
| I | Greater trochanter | |
| II | ||
| III | ||
| IV | Distal to tip | |
| V | ||
| VI | ||
| VII | Lesser trochanter |