Evidence map›Paper›PMID 41689012›Full record

ArticleBMC musculoskeletal disorders2026

Finite element analysis of the influence of femoral neck system implantation angle on biomechanical stability in femoral neck fractures: a mechanistic exploration.

Haohao Bai, Ying Wang, Hongzhen Jin, Bin Lu, Lei Sun, Xinlong Ma, Jianxiong Ma

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Article in BMC musculoskeletal disorders, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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5 · Who and what money

Authors and funding

7 authors.

Haohao Bai *Tianjin Hospital, Tianjin University, Tianjin, 300050, China.
Ying Wang *Tianjin Hospital, Tianjin University, Tianjin, 300050, China.
Hongzhen Jin *Tianjin Hospital, Tianjin University, Tianjin, 300050, China.
Bin LuTianjin Hospital, Tianjin University, Tianjin, 300050, China.
Lei SunTianjin Hospital, Tianjin University, Tianjin, 300050, China.
Xinlong MaTianjin Hospital, Tianjin University, Tianjin, 300050, China. maxinlong@126.com.
Jianxiong MaTianjin Hospital, Tianjin University, Tianjin, 300050, China. majianxiong2023@126.com.

Funding

Tianjin Science and Technology planning Project No. 25JCYBJC00540
6 · The paper itself

Abstract

backgroundFemoral neck fractures pose significant therapeutic challenges. The femoral neck system (FNS) has emerged as a promising implant. However, deviations in the nail-shaft angle during FNS placement may compromise biomechanical stability, yet their impact remains poorly understood. We aimed to investigate the biomechanical effects of varying nail-shaft angles on stress distribution in FNS-treated femoral neck fractures (graded according to Pauwels classification) using finite element analysis, providing insights for intraoperative precision.

methodsThree-dimensional models of Pauwels type I-III fractures were reconstructed from computed tomography scans of a healthy adult femur. The FNS implants with nail-shaft angles of 120°, 125°, 130°, 135°, and 140° were virtually positioned. Axial loading (1,400 N) was simulated via finite element analysis (Abaqus 2020) to evaluate the Von Mises stress distribution, peak stress magnitude, and stress transmission efficiency, and to compare mechanical failure risks across fracture types.

resultsIn Pauwels type I and III fractures, a 130° nail-shaft angle minimised the peak Von Mises stress (102.7 MPa and 114.7 MPa, respectively), with stress concentrated near the fracture line, indicating optimal load transfer. For Pauwels type II fractures, an angle of 120° yielded the lowest peak stress (126.4 MPa). Angle deviations significantly altered stress patterns: at angles ≤ 130°, type I fractures exhibited lower stress than types II/III; conversely, angles ≥ 135° reversed this trend. Angles > 130° shifted the stress concentration to the distal locking screws, thereby elevating the risk of mechanical failure.

conclusionsThe biomechanical performance of the FNS is fracture-type-dependent, necessitating angle-specific optimisation. For Pauwels type I/III fractures, optimal nail placement at 130° enhances stress distribution, whereas type II fractures may benefit from 120° angulation. These findings underscore the criticality of intraoperative angle control in mitigating fixation failure and non-union risk. Future studies should incorporate clinical follow-ups and multi-axis loading to validate these biomechanical insights.

Indexed as

Femoral Neck FracturesFracture Fixation, InternalBiomechanical PhenomenaBone NailsFinite Element AnalysisHumansProximal Femoral FracturesStress, MechanicalTomography, X-Ray ComputedAngle deviationBiomechanicsFemoral neck fractureFemoral neck systemFinite element analysisInternal fixation optimization

Identifiers

PMID41689012
PMCPMC13032543

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.