Whole muscle length-tension relationships are accurately modeled as scaled sarcomeres in rabbit hindlimb muscles

JOURNAL OF BIOMECHANICS

卷:44

Article

Winters, Taylor M.^1,2  Takahashi, Mitsuhiko^3,4  Lieber, Richard L.^1,2,3,4  Ward, Samuel R.^1,2,5,6 

[1] Univ Calif San Diego, Dept Bioengn, San Diego, CA 92161 USA

[2] Vet Adm Med Ctr, Dept Bioengn, San Diego, CA 92161 USA

[3] Univ Calif San Diego, Dept Orthopaed Surg, San Diego, CA 92161 USA

[4] Vet Adm Med Ctr, Dept Orthopaed Surg, San Diego, CA 92161 USA

[5] Vet Adm Med Ctr, Dept Radiol, San Diego, CA 92161 USA

[6] Univ Calif San Diego, Dept Radiol, San Diego, CA 92161 USA

关键词: Length-tension relationship;    Muscle architecture;    Muscle Function;    Modeling;   

DOI  :  10.1016/j.jbiomech.2010.08.033

来源: Elsevier

【 摘 要 】

An a priori model of the whole active muscle length-tension relationship was constructed utilizing only myofilament length and serial sarcomere number for rabbit tibialis anterior (TA), extensor digitorum longus (EDL), and extensor digitorum II (EDII) muscles. Passive tension was modeled with a two-element Hill-type model. Experimental length-tension relations were then measured for each of these muscles and compared to predictions. The model was able to accurately capture the active-tension characteristics of experimentally-measured data for all muscles (ICC=0.88 +/- 0.03). Despite their varied architecture, no differences in predicted versus experimental correlations were observed among muscles. In addition, the model demonstrated that excursion, quantified by full-width-at-half-maximum (FWHM) of the active length-tension relationship, scaled linearly (slope=0.68) with normalized muscle fiber length. Experimental and theoretical FWHM values agreed well with an intraclass correlation coefficient of 0.99 (p < 0.001). In contrast to active tension, the passive tension model deviated from experimentally-measured values and thus, was not an accurate predictor of passive tension (ICC=0.70 +/- 0.07). These data demonstrate that modeling muscle as a scaled sarcomere provides accurate active functional but not passive functional predictions for rabbit TA, EDL, and EDII muscles and call into question the need for more complex modeling assumptions often proposed. Published by Elsevier Ltd.

【 授权许可】

Free