Load transmission through a healing tibial fracture.
BACKGROUND
Fracture healing has been linked to both the magnitude and distribution of mechanical stresses on the healing fracture tissues. However, direct clinical measurement of in vivo tibial axial loading is not possible.


METHODS
Using computed tomography images, force plate data and recorded 3D interfragmentary micromovements, accurate 3D finite element models of a healing human tibial fracture were generated at 7, 10, and 16 weeks post-fracture and used to calculate longitudinal tibial forces and external fixator load-sharing during bilateral stance and walking.


RESULTS
Tibial load-sharing by the fixator decreased significantly as the fracture tissues developed even moderate stiffness, while tibial load increased steadily towards normal.


CONCLUSIONS
Quantitative assessment of the contribution of the external fixator is important as overloading of the callus due to insufficient support has been implicated in the retardation of the healing process.
Vijayakumar
V
V
Oxford Orthopaedic Engineering Centre (OOEC), University of Oxford, UK. vinod@intsoph.org
Marks
L
L
Bremmer-Smith
A
A
Hardy
J
J
Gardner
T
T
D000328:Adult; D003198:Computer Simulation; D004548:Elasticity; D020342:Finite Element Analysis; D005592:Fracture Fixation; D017102:Fracture Healing / Q000502:physiology*; D006801:Humans; D008297:Male; D008954:Models, Biological; D011187:Posture; D013314:Stress, Mechanical; D013977:Tibia / Q000503:physiopathology* / Q000601:surgery; D013978:Tibial Fractures / Q000503:physiopathology* / Q000601:surgery; D016896:Treatment Outcome; D016138:Walking; D016474:Weight-Bearing