26dkou411 10.3205/26dkou411 urn:nbn:de:0183-26dkou4116 Meeting Abstract Philipp Philipp Robert R

Department of Orthopaedic and Trauma Surgery, Leipzig University Hospital, Leipzig, Deutschland

author Kalb Kalb Anke A

Department of Orthopaedic and Trauma Surgery, Leipzig University Hospital, Leipzig, Deutschland

author Notov Notov Dmitry D

Department of Orthopaedic and Trauma Surgery, Leipzig University Hospital, Leipzig, Deutschland

author Kleber Kleber Christian C

Department of Orthopaed and Trauma Surgery, Leipzig University Hospital, Leipzig, Deutschland

author Spiegl Spiegl Ulrich U

Department of Orthopaedic and Trauma Surgery, Leipzig University Hospital, Leipzig, Deutschland Department of Orthopaedics, Trauma Surgery and Reconstructive Surgery, München Klinik Harlaching, 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 411 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) Poster | Der geriatrische Patient Berlin 20261020 20261023 DKOU26_Abs_2458 TextObjectives and questions: To determine whether cephalomedullary nail geometry—specifically nail length and CCD configuration—independently influences (i) achieving a tip–apex distance (TAD) <25 mm and (ii) early mechanical lag screw cut-out within 90 days after fixation of trochanteric femur fractures (AO/OTA 31-A1 to 31-A3) in a predominantly geriatric cohort. We further assessed contralateral CCD mismatch as a potential contributor to technical difficulty.Material and methods: Retrospective single-centre cohort study (2018–2022). Consecutive patients with AO/OTA 31-A1 to 31-A3 fractures treated with cephalomedullary nails were analysed. Primary radiographic outcome was TAD <25 mm on immediate postoperative radiographs; primary clinical outcome was mechanical cut-out ≤90 days. Multivariable logistic regression assessed predictors of TAD <25 mm (including nail length, screw position, age, fracture type, reduction quality). Due to sparse cut-out events, Firth-penalised logistic regression was used for cut-out modelling. Time-to-event analyses applied Kaplan–Meier estimates and penalised Cox regression. Contralateral CCD and absolute CCD mismatch were evaluated when contralateral imaging was available. A predefined homogeneous subgroup (AO/OTA 31-A2, good reduction by Baumgaertner criteria, 130° nails) was analysed separately.Results: For TAD analysis, 373 patients were eligible; for cut-out analyses 351 remained after excluding 22 in-hospital deaths. Median age was 83 years and 62.7% were female. TAD <25 mm was achieved in 313/373 (83.9%) and centre–centre screw position in 324/373 (86.9%). Early cut-out occurred in 16/351 (4.6%); no event occurred after day 65. Nail length and CCD configuration were not independently associated with TAD attainment or cut-out (e.g., nail length OR 1.27, 95% CI 0.55–2.91 for TAD <25 mm; cut-out OR 0.60, 95% CI 0.16–1.87). Centre–centre screw placement was strongly associated with TAD <25 mm (OR 14.98, 95% CI 7.35–30.54) and lower cut-out risk (OR 0.23, 95% CI 0.09–0.69). TAD <25 mm was associated with reduced cut-out (OR 0.29, 95% CI 0.11–0.86). In contralateral analyses, non-130° constructs showed greater CCD mismatch than 130° constructs, without a corresponding increase in early cut-out.Discussion and conclusions: In this geriatric trochanteric fracture cohort, implant geometry (nail length, CCD configuration) did not independently determine TAD attainment or early mechanical cut-out. In contrast, technically modifiable factors—centre–centre screw position and achieving TAD <25 mm—were consistently associated with construct stability. Increased CCD mismatch in non-130° constructs was not linked to higher early cut-out but may still be relevant in atypical anatomies. 0 0 0 0