The Role of Lower-Limb Geometry in the Pathophysiology of Atypical Femoral Fracture

  • Ifaz T. Haider
  • Prism S. Schneider
  • W. Brent EdwardsEmail author
Epidemiology and Pathophysiology (F Cosman and D Shoback, Section Editors)
Part of the following topical collections:
  1. Topical Collection on Epidemiology and Pathophysiology


Purposeof Review

The etiology of atypical femoral fracture (AFF) is likely multifactorial. In this review, we examined the recent literature investigating the role of lower-limb geometry in the pathophysiology of AFF.

Recent Findings

Increased femoral bowing was associated with prevalent AFF and a greater likelihood of a diaphyseal versus a subtrochanteric AFF location. Femoral neck geometry or hip alignment may also be related to AFF, but findings remain equivocal. Differences in femoral geometry may, in part, be responsible for the high rate of AFF in Asian compared with Caucasian populations. Finally, simulation studies suggest that lower-limb geometry influences AFF risk via its effects on mechanical strain of the lateral femoral cortex.


Femoral geometry, and bowing in particular, is related to prevalent AFF, but more prospective investigation is needed to determine whether measurements of geometry can be used for clinical risk stratification.


Osteoporosis Bisphophonates Femoral bowing Hip geometry Femoral strain Fracture risk 


Compliance with Ethical Standards

Conflict of Interest

Ifaz Haider and Brent Edwards reports grants from Amgen outside the submitted work. Prism Schneider declares no conflict of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Ifaz T. Haider
    • 1
    • 2
  • Prism S. Schneider
    • 2
    • 3
  • W. Brent Edwards
    • 1
    • 2
    Email author
  1. 1.Human Performance Laboratory, Faculty of KinesiologyUniversity of CalgaryCalgaryCanada
  2. 2.McCaig Institute for Bone and Joint HealthUniversity of CalgaryCalgaryCanada
  3. 3.Department of Surgery; Department of Community Health Sciences, Cumming School of Medicine, Foothills CampusUniversity of CalgaryCalgaryCanada

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