Related Experiment Video
Updated: Feb 15, 2026

Individualized Stem-positioning in Calcar-guided Short-stem Total Hip Arthroplasty
Published on: February 27, 2018
Inter- and intra-operator reliability in patient-specific template positioning for total hip arthroplasty. A cadaver
Manuel Krämer1, Lüder A Kahrs2, Karl-Ingo Friese3
1Laboratory for Biomechanics and Biomaterials, Hannover Medical School, Hannover, Germany.
Background:
The implantation of the acetabular cup essentially determines the clinical outcome of total hip arthroplasty. To address this issue, the aim of this study was to build patient-specific instruments (PSIs) with various reference surfaces, followed by in vitro investigations to examine the inter- and intra-operator reliability as well as the overall precision of these patient-specific templates.
Methods:
Seven human hemi-pelvis specimens were used for this study. After a CT scan, PSIs with different imprint heights were created. The overall precision of the templates and the inter- and intra-operator reliabilities were calculated.
Results:
Strong differences in precision between the PSI designs could be observed. The desired orientation of the acetabular cup could be adjusted with a precision of up to 1.55°.
Conclusion:
Based on our results, we believe that the application of the PSI-based acetabular cup positioning in total hip arthroplasty procedures can potentially increase the precision of cup placement.
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