25dkou487 10.3205/25dkou487 urn:nbn:de:0183-25dkou4878 Meeting Abstract Hax Hax Jakob J

Schulthess Klinik, Zürich, Schweiz

author Zderic Zderic Ivan I

AO Research Institute Davos (ARI), Davos, Schweiz

author Gueorgiuev Gueorgiuev Boyko B

AO Research Institute Davos (ARI), Davos, Schweiz

author Leunig Leunig Michael M

Schulthess Klinik, Zürich, Schweiz

author Pape Pape Hans-Christoph HC

Universitätsspital Zürich, Zürich, Schweiz

author Rüdiger Rüdiger Hannes A. HA

Schulthess Klinik, Zürich, Schweiz

author German Medical Science GMS Publishing House

Düsseldorf

610 20251031 engl This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). M0634 487 Deutsche Gesellschaft für Orthopädie und Unfallchirurgie Deutsche Gesellschaft für Orthopädie und Orthopädische Chirurgie Deutsche Gesellschaft für Unfallchirurgie Berufsverband für Orthopädie und Unfallchirurgie Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2025) Abstracts | Becken- und Hüftchirurgie – Prothetik Berlin 20251028 20251031 AB77-4111 TextObjectives and questions: While many femoral revisions may be performed using primary stems, there is a wide range of revision stems available. Most of them are long and have a conical design with a round shape in cross-section. They typically aim for distal diaphyseal fixation. The DePuy Synthes CORAIL® revision stem (REV) offers an intermediate option. Unlike the standard CORAIL® stem (STD), it is 39 mm longer and slotted distally to adapt to the femoral diaphysis’s anterior bowing. This study aims to compare the axial and rotational stability of STD and REV stems in an artificial bone model.Material and methods: Using a SYNBONE®-model, 12 STD (size 11, 135°) and 12 REV (size 11, 135°) collared hip stems were implanted. Neck osteotomies were performed 20mm above the lesser trochanter, and the femoral canal was prepared with compaction broaches. Four groups (n=6 each) were evaluated: (1) STD and (2) REV with axial loading (500 cycles at 20° adduction, up to 500 N at 1 Hz (50/s), and quasi-static loading to failure); and (3) STD and (4) REV with torsional loading (500 cycles up to 10 Nm internal rotation at 1 Hz, and quasi-static loading to failure). Based on acquired machine data, stiffness at final loading ramp (axial N/mm; torsional Nm/°) and peak load (N)/torque (Nm) at failure were measured. Statistical evaluation as explorative data analysis (mean ± standard deviation (SD)) using One-Way ANOVA with Bonferroni/Games-Howell post-hoc analysis (p≤0.05 considered significant).Results: REV demonstrated significantly higher axial stiffness (302.3 ± 17.4 N/mm) compared to STD (217.4 ± 20.7 N/mm, p<0.001) and was more resistant to peak axial force (1173.7 ± 73.5 N vs. STD 1032.0 ± 63.0 N, p=0.061). Torsional stiffness was also higher for REV (2.42 ± 0.13 Nm/° vs. STD 1.90 ± 0.17 Nm/°, p=0.002). However, peak torque at failure was comparable (STD: 40.9 ± 4.5 Nm, REV: 46.6 ± 1.7 Nm, p=0.206). Axial failure occurred at the distal stem tip, while torsional failure involved proximal rotation and spiral fracture distally.Discussion and conclusions: The REV stem’s extended distal length improved axial and torsional stiffness and increased peak load compared to STD in artificial bone models. However, peak torque remained unaffected, and the advantages of the REV stem may not be critical in primary arthroplasty. These findings align with the excellent clinical performance of the standard stem. In revision cases with osteolysis or osteotomies, the biomechanical benefits of REV warrant further evaluation. 0 0 0 0