TY - JOUR
T1 - Effect of compression and anisotropy on the diffusion of glucose in annulus fibrosus
AU - Jackson, Alicia R.
AU - Yuan, Tai Yi
AU - Huang, Chun Yuh C.
AU - Travascio, Francesco
AU - Yong Gu, Wei
PY - 2008/1
Y1 - 2008/1
N2 - STUDY DESIGN. Investigation of the effect of static compression and anisotropy on the apparent diffusivity of glucose in bovine annulus fibrosus (AF). OBJECTIVE. To determine the apparent glucose diffusivity in 2 directions (axial and radial) of bovine AF under 3 levels of compressive strain (0%, 10%, and 20%). SUMMARY OF BACKGROUND DATA. Knowledge of diffusivity of small molecules is important for understanding nutritional supply in intervertebral discs and the mechanisms of disc degeneration. However, little is known regarding the strain-dependent and anisotropic behavior of glucose diffusivity in intervertebral discs. METHODS. Apparent glucose diffusivity measurements were performed on 10 axial and 10 radial AF specimens from bovine coccygeal discs. The dependence of diffusivity on compression was determined using 3 levels of strain (0%, 10%, and 20%). RESULTS. The apparent glucose diffusivity (mean ± standard deviation) of the bovine AF in the axial direction was 1.38 ± 0.015 × 10 cm/s (n = 10) at 0%, 1.00 ± 0.070 × 10 cm/s (n = 10) at 10%, and 7.65 ± 0.552 × 10 cm/s (n = 10) at 20% compression. For radial specimens, the apparent glucose diffusivity was determined to be 9.17 ± 1.12 × 10 cm/s (n = 10), 7.29 ± 0.863 × 10 cm/s (n = 10), and 5.43 ± 1.16 × 10 cm/s (n = 10) for 0%, 10%, and 20% compressions, respectively. A significant decrease in diffusivity with increasing strain was found for both axial and radial specimens [analysis of variance (ANOVA), P < 0.05]. Diffusion in the radial direction was determined to be significantly less than that in the axial direction (ANOVA, P < 0.05). A significant interaction was found between the level of strain and the direction of diffusion (ANOVA, P < 0.05). CONCLUSION. Diffusion of glucose in bovine AF is dependent on strain and the direction of diffusion.
AB - STUDY DESIGN. Investigation of the effect of static compression and anisotropy on the apparent diffusivity of glucose in bovine annulus fibrosus (AF). OBJECTIVE. To determine the apparent glucose diffusivity in 2 directions (axial and radial) of bovine AF under 3 levels of compressive strain (0%, 10%, and 20%). SUMMARY OF BACKGROUND DATA. Knowledge of diffusivity of small molecules is important for understanding nutritional supply in intervertebral discs and the mechanisms of disc degeneration. However, little is known regarding the strain-dependent and anisotropic behavior of glucose diffusivity in intervertebral discs. METHODS. Apparent glucose diffusivity measurements were performed on 10 axial and 10 radial AF specimens from bovine coccygeal discs. The dependence of diffusivity on compression was determined using 3 levels of strain (0%, 10%, and 20%). RESULTS. The apparent glucose diffusivity (mean ± standard deviation) of the bovine AF in the axial direction was 1.38 ± 0.015 × 10 cm/s (n = 10) at 0%, 1.00 ± 0.070 × 10 cm/s (n = 10) at 10%, and 7.65 ± 0.552 × 10 cm/s (n = 10) at 20% compression. For radial specimens, the apparent glucose diffusivity was determined to be 9.17 ± 1.12 × 10 cm/s (n = 10), 7.29 ± 0.863 × 10 cm/s (n = 10), and 5.43 ± 1.16 × 10 cm/s (n = 10) for 0%, 10%, and 20% compressions, respectively. A significant decrease in diffusivity with increasing strain was found for both axial and radial specimens [analysis of variance (ANOVA), P < 0.05]. Diffusion in the radial direction was determined to be significantly less than that in the axial direction (ANOVA, P < 0.05). A significant interaction was found between the level of strain and the direction of diffusion (ANOVA, P < 0.05). CONCLUSION. Diffusion of glucose in bovine AF is dependent on strain and the direction of diffusion.
KW - Compressive strain
KW - Diffusion coefficient
KW - Intervertebral disc
KW - Spine
KW - Transport
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U2 - 10.1097/BRS.0b013e31815e4136
DO - 10.1097/BRS.0b013e31815e4136
M3 - Article
C2 - 18165741
AN - SCOPUS:37649010348
VL - 33
SP - 1
EP - 7
JO - Spine
JF - Spine
SN - 0362-2436
IS - 1
ER -