26dkou063 10.3205/26dkou063 urn:nbn:de:0183-26dkou0634 Meeting Abstract Beckers Beckers Gautier G

Klinikum der Universität München Campus Großhadern, München, Deutschland

author Cheers Cheers Giles G

Klinikum der Universität München Campus Großhadern, München, Deutschland

author Simon Simon Dominic D

Klinikum der Universität München Campus Großhadern, München, Deutschland

author Holzapfel Holzapfel Boris B

Klinikum der Universität München Campus Großhadern, München, Deutschland

author Schröder Schröder Lennart L

Klinikum der Universität München Campus Großhadern, München, Deutschland

author German Medical Science GMS Publishing House

Düsseldorf

610 20261020 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). M0659 063 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 2026) Abstracts | Implantatdesign und Primärimplantation der Hüft-TEP Berlin 20261020 20261023 DKOU26_Abs_2447 TextObjectives and questions: The McKibbin index, combining femoral and acetabular version, is a key determinant of hip stability and impingement risk. Aberrant combined version patterns may pose intraoperative challenges, yet their population distribution remains poorly defined. Moreover, the relationship between hip morphology, lower limb alignment, and pelvic parameters is not fully understood. The primary aim of this study is to comprehensively phenotype femoroacetabular anatomy in a large cohort and to evaluate correlations between the McKibbin index, hip morphology, lower limb alignment, and spinopelvic parameters.Material and methods: We retrospectively analyzed 2,500 preoperative rotational CT planning datasets provided by Symbios S.A., all acquired using standardized protocols to ensure consistent image quality and geometry. A reproducible Python pipeline processed each case from raw imaging to structured measurement tables. Anatomies were segmented using TotalSegmentator. Predefined planning landmarks were combined with automated geometric landmarking. Sacral landmarking identified the center and surface normal of the superior sacral endplate, while tibial landmarking determined the tibial anatomical axis and proximal tibial plateau landmarks. Based on these landmarks, clinically relevant alignment and spinopelvic parameters were computed, including three-dimensional and coronal hip–knee–ankle angle, MPTA, LDFA, femoral neck length, femoral head position, pelvic incidence, and pelvic tilt. Hips were classified by femoral CCD angle into varus (<1 SD), neutral (±1 SD), and valgus (>1 SD). Group comparisons were performed using the Kruskal–Wallis test with Dunn’s post hoc correction for non-normally distributed data. Analyses were conducted using Python 3.9.6 and SciPy 1.13.1. Correlation analyses with lower limb parameters are ongoing.Results: All hips were classified according to CCD morphology: 6.8% varus (CCD < 124.45°), 84.4% neutral (124.45°–137.58°), and 8.9% valgus (> 137.58°). Femoral offset differed significantly across groups (p < 0.001), with valgus hips demonstrating significantly lower offset compared with both neutral and varus hips. Femoral anteversion also varied significantly (p = 0.004), with varus hips showing higher anteversion (18.69 ± 6.31°) than neutral (11.18 ± 11.24°) and valgus hips (5.71 ± 20.56°). In contrast, acetabular anteversion (overall mean 22.4° ± 7.5°) did not differ across CCD categories. Combined femoral and acetabular version patterns were heterogeneously distributed, with the majority falling within physiologic version ranges. The distribution of hip and acetabular anatomy using the McKibbin index is described in Table 1 .Discussion and conclusions: Large-scale CT phenotyping demonstrates that CCD morphology is associated with femoral offset and femoral anteversion, while acetabular anteversion remains independent. The McKibbin index shows a predominantly physiologic but heterogeneous distribution, providing a robust anatomical reference for preoperative planning. 11

Table 1

1 0 0 0