The biomechanical properties of canine skin measured in situ by uniaxial extension.
BACKGROUND
A uniaxial extension system was setup to analyze the mechanical properties of dog skin.


METHODS
Pads were glued onto dog skin with constant reproducible geometrical parameters and the extension force was measured as a function of the extension values. Forty-one sites (82 cycling tests) were investigated in situ on 11 canine cadavers, half of them after surgically isolating the test area from the surrounding skin. Series of loading-unloading cycles of up to 5N or 10N or both loads were performed on each site. The elastic properties and the dissipative effects were characterized respectively by evaluating the secant Rigidity at maximum loads and the Fraction of dissipated energy.


RESULTS
A hysteresis phenomenon, implying the need for preconditioning to attain equilibrium cycles, was apparent during mechanical characterization. Polynomial expressions were used to relate the measured Rigidities and the Fractions of dissipated energy with or without sample isolation. The latter were less affected by isolation. The ratios between the Rigidities at 5N to those at 10N displayed non-linearity in the investigated extension range in contrary to the Fractions of dissipated energy.


CONCLUSIONS
The parameters confirming the dissipative non-linear elastic behavior of dog skin were identified and the correlation between Rigidity and Fraction of dissipated energy on isolated and non-isolated skin samples was quantitatively determined. This extension setup can now be used as a "true in vivo" mapping tool to determine the mechanical characteristics of the skin during healing processes or during the study of Human skin disease with the dog as an animal model.
CHEVAC, Small Animal Department, VetAgro Sup, Campus vétérinaire de Lyon, University of Lyon, F-69280 Marcy l'Etoile, France. UPSP 2011.03.101 ICE, VetAgro Sup, Université de Lyon, 69280 Marcy L'Etoile, France. Electronic address: camille.bismuth@vetagro-sup.fr.
Camille
C
Bismuth
CHEVAC, Small Animal Department, VetAgro Sup, Campus vétérinaire de Lyon, University of Lyon, F-69280 Marcy l'Etoile, France. UPSP 2011.03.101 ICE, VetAgro Sup, Université de Lyon, 69280 Marcy L'Etoile, France.
Clothilde
C
Gerin
CHEVAC, Small Animal Department, VetAgro Sup, Campus vétérinaire de Lyon, University of Lyon, F-69280 Marcy l'Etoile, France. UPSP 2011.03.101 ICE, VetAgro Sup, Université de Lyon, 69280 Marcy L'Etoile, France.
Eric
E
Viguier
CHEVAC, Small Animal Department, VetAgro Sup, Campus vétérinaire de Lyon, University of Lyon, F-69280 Marcy l'Etoile, France. UPSP 2011.03.101 ICE, VetAgro Sup, Université de Lyon, 69280 Marcy L'Etoile, France.
Didier
D
Fau
Université de Lyon, Université Claude Bernard Lyon 1, Laboratoire Ingénierie des Matériaux Polymères (IMP@Lyon1), CNRS UMR 5223, Bât. Polytech Lyon, 15 bd Latarjet 69622, Villeurbanne Cedex, France.
Florence
F
Dupasquier
Université de Lyon, Université Claude Bernard Lyon 1, Laboratoire Ingénierie des Matériaux Polymères (IMP@Lyon1), CNRS UMR 5223, Bât. Polytech Lyon, 15 bd Latarjet 69622, Villeurbanne Cedex, France.
Laurent
L
Cavetier
Université de Lyon, Université Claude Bernard Lyon 1, Laboratoire Ingénierie des Matériaux Polymères (IMP@Lyon1), CNRS UMR 5223, Bât. Polytech Lyon, 15 bd Latarjet 69622, Villeurbanne Cedex, France.
Laurent
L
David
CHEVAC, Small Animal Department, VetAgro Sup, Campus vétérinaire de Lyon, University of Lyon, F-69280 Marcy l'Etoile, France. UPSP 2011.03.101 ICE, VetAgro Sup, Université de Lyon, 69280 Marcy L'Etoile, France.
Claude
C
Carozzo
D000818:Animals; D001696:Biomechanical Phenomena; D001703:Biophysics; D004285:Dogs; D004548:Elasticity; D066298:In Vitro Techniques; D012879:Skin Physiological Phenomena
Biomechanical properties; Dogs; Extensometer; In vivo; Skin measurement device