Specialized Surgical Tools
Controlled Acetabular Cup Medialization Tool for Total Hip Arthroplasty
A dedicated surgical-assist tool for controlled acetabular cup medialization in total hip arthroplasty. Developed with the 2nd Department of Orthopaedics of Athens General Hospital “G. Gennimatas”, engineered by MD-Lab, and manufactured by Prematech from biocompatible SAE 316L stainless steel, the prototype helps surgeons transfer impaction loads more effectively while preserving cup orientation.
Impact
During total hip arthroplasty, cup medialization is one of the moments where surgical precision and mechanical force meet. The surgeon needs the cup to reach full contact with the prepared acetabular bone, but hammering loads are not always transferred in the desired direction. This can make the implant harder to medialize, especially in sclerotic bone, and can force repeated corrections to maintain the planned abduction and anteversion.
The tool addresses this problem by giving the surgeon a more controlled mechanical interface for impact loading. Its geometry helps redirect the applied force along an axis more favorable to medialization, so the cup can be advanced inward while orientation control is preserved. In pilot use, the prototype was especially helpful in demanding cases with hard bone, where conventional handling can make controlled seating more difficult.
MD-Lab’s Contribution
MD-Lab turned the surgical need into a robust and manufacturable mechanical solution. The laboratory supported the functional layout, the adjustable geometry, and the design logic needed for intraoperative use with existing arthroplasty instrumentation.
A finite element model was developed in ANSYS Workbench to assess the tool under shock loading before use in surgery. This helped confirm that the concept could withstand repeated impaction, after which Prematech manufactured the prototype from biocompatible SAE 316L stainless steel using conventional machining processes.
