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Biomechanics of Intramedullary Rods for Fracture Fixation

Biomechanics of Intramedullary Rods for Fracture Fixationuser.engineering.uiowa.edu/~bme_158/Lecture/Intramedullary Nails.pdf · Influences of Some Design Parameters on the Biomechanics

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Biomechanics of Intramedullary Rods for Fracture Fixation

Ultimate Properties of Intramedullary Nails

Martens M. Frankel VH, Burstein AH

Injury 4: 18-24, 1973

IM Nail Loading

Load-Deformation Comparisons

Permanent Deformation

Nail Designs

Four-Point Bending

Deflection vs. Diameter Deformation

Yield Points

Stress Analysis of a Partially Slotted Intramedullary Nail

Beaupré GS, Schneider E, Perren SM

J. Orthop. Res. 2: 369-376, 1984

AO 13mm Femoral Nail

FEM of Standard

Nail

FEM of Cloverleaf

Nail

Cracked Nails

Loading Configurations

Validation Strain Gaging

Slot Tip Alternatives

FEM vs. Experiment

Maximum Stresses

Influences of Some Design Parameters on the Biomechanics of the Unreamed

Tibial Intramedullary Nail

Henley MB, Meier M, Tencer AF

J. Orthop. Trauma 7: 311-319, 1993

Fixation Plates

IM Rods

Radiographic Appearance

Testing Set-up

Work to Failure

Breaking Strength

Flexoral Stiffness

Bone Cross-Sectional Area

Radiographic Healing

Mechanical Characterization of Femoral Interlocking Intramedullary Nailing

Systems

Russell TA, Taylor JC, LaVelle DG, Beals NB, Brumfield DL, Durham AG

J. Ortho. Trauma 5: 332-340, 1991

Loading Fixture

A BC

A: AO

B: R-T

C: Mal-reduced Roddings

Anterior Impingement

Translation vs. Effective Diameter

Impingement

Construct Stiffness

Effects of Locking Screw Orientation

Effects of Cortical Contact

The Effect of Implant Axial and Torsional Stiffness on Fracture Healing

Woodard PL, Self J, Calhoun J, Tencer AF, Evans EB

J. Orthop. Trauma 1: 331-340, 1998

Flexural Testing Fixture

Torsion Testing

Nail Cross-sections (Digitized)

Bending Stiffness

Bending Strength

Closed

Open

St. Venant Torsional Constants

Strength of 13 mm nails

Screw Strength (3-point Bending)

} Theoretical

Bending stiffness from moment of inertia

Stiffness of 13mm nails

Torsional Load Uptake

Torisonal Stiffness (from moment of inertia)