Oishi Motoharu, Ogihara Naomichi, Endo Hideki, Asari Masao
Department of Anatomy 1st, School of Veterinary Medicine, Azabu University, Kanagawa, 229-8501, Japan.
Primates. 2008 Jul;49(3):204-9. doi: 10.1007/s10329-008-0082-5. Epub 2008 Mar 1.
We dissected the left upper limb of a female orangutan and systematically recorded muscle mass, fascicle length, and physiological cross-sectional area (PCSA), in order to quantitatively clarify the unique muscle architecture of the upper limb of the orangutan. Comparisons of the musculature of the dissected orangutan with corresponding published chimpanzee data demonstrated that in the orangutan, the elbow flexors, notably M. brachioradialis, tend to exhibit greater PCSAs. Moreover, the digital II-V flexors in the forearm, such as M. flexor digitorum superficialis and M. flexor digitorum profundus, tend to have smaller PCSA as a result of their relatively longer fascicles. Thus, in the orangutan, the elbow flexors demonstrate a higher potential for force production, whereas the forearm muscles allow a greater range of wrist joint mobility. The differences in the force-generating capacity in the upper limb muscles of the two species might reflect functional specialization of muscle architecture in the upper limb of the orangutan for living in arboreal environments.
我们解剖了一只雌性猩猩的左上肢，并系统地记录了肌肉质量、肌束长度和生理横截面积（PCSA），以便定量阐明猩猩上肢独特的肌肉结构。将解剖的猩猩肌肉组织与已发表的相应黑猩猩数据进行比较，结果表明，在猩猩中，肘部屈肌，尤其是肱桡肌，往往具有更大的PCSA。此外，前臂的第II - V指屈肌，如指浅屈肌和指深屈肌，由于其肌束相对较长，往往具有较小的PCSA。因此，在猩猩中，肘部屈肌表现出更高的力量产生潜力，而前臂肌肉则允许腕关节有更大的活动范围。这两个物种上肢肌肉力量产生能力的差异可能反映了猩猩上肢肌肉结构为适应树栖环境而进行的功能特化。
