Mineralized tendon

Yamauchi M and Katz EP (1993) The post-translational chemistry and molecular packing of mineralizing tendon collagens. Connect Tissue Res 29, 81-98. 

In particular, the gastrocnemius, or Achilles tendon structure of the domestic turkey and manner of mineralization tendon have been described... 

Determination of Elastic and Viscous Properties of Mineralized Tendon... 

Elastic and viscous stress-strain curves for unmineralized and mineralized turkey tendons are plotted in Figure 7.5. In general, the elastic stress-strain curves for tendons with low mineral content (0.029 weight fraction of mineral) are lower than those that are seen for mineralized tendons (mineral content about 0.3). 

Mechanical models of mineralized tendons follow from the analyses done for tendon. The elastic moduli of mineralized turkey tendons have been calculated from the experimental elastic incremental stress-strain curves. For mineralized tendons the stress-strain curves are linear at mineral content of about 0.3 and the elastic modulus is about 8GPa and increases with... 

Silver FH, Freeman JW, Horvath I, Landis WJ. Molecular basis for elastic energy storage in mineralized tendon. Biomacromol. 2001 2 750-756. 

Fig. 3 Typical hieiaicliical structures of load-bearing biological materials (a) bone, (b) mineralized tendon fibre, and (c) shell (reprinted with pmnission fiom [82])...

Musculoskeletal- Mild to moderate musculoskeletal symptoms, including arthralgia, that occasionally require drug discontinuation and rarely persist after discontinuation (16%) skeletal hyperostosis (see Warnings) calcification of tendons and ligaments premature epiphyseal closure arthritis tendonitis other bone abnormalities decreases in bone mineral density back pain rhabdomyolysis (rare postmarketing reports). 

Fratzl, P., Fratzl-Zelman, N., and Klaushofer, K. (1993). Collagen packing and mineralization. An X-ray scattering investigation of turkey leg tendon. Biophys. J. 64, 260-266. 

The skeletal age, which is not necessarily identical with the calendar age of the individual, has an important impact on the fluorine uptake, because osteoporosis is a process that fundamentally influences the bone structure. The disease pattern becomes visible in material loss within both the trabecular and the compact bone structure. Furthermore, the mineral density even in a healthy individual is not uniform in compact bone, but is a function of bone stress at this skeletal position and is increased at the point where muscles and tendons are fixed. 

Figure 3.30. X-ray showing mineral deposition in turkey leg tendon. Light areas reflect mineral that is electron dense forming on the collagen fibrils in tendon (Landis and Silver, 2002).

On the other hand, as noted above, the mineralization of the turkey gastrocnemius has been studied extensively. Mineral deposition appears to involve two distinct components of the tendon type I collagen and small vesicles that are found in the extracellular spaces between the collagen fibrils organized in long, parallel, and highly aligned arrays. 

Microscopically, vesicles initially appear conspicuous in the region of the tendon containing larger tenocytes and undergoing the transition to mineralization, just proximal to the mineral front. The early appearance of mineral in the tendon is found in association with these vesicles. Later, that is, closer to the mineral front, collagen also mediates mineral deposition and ultimately the bulk of the mineral is associated with this matrix component (Figure 3.31). 

Landis WJ, Silver FH. The structure and function of normally mineralizing avian tendons. Comparative Biochemistry and physiology 2002 133 1135-1157. 

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