An inquiry into the comparative forces of the extensor and flexor muscles, connected with the joints of the human body / [Julius Jeffreys].

  • Jeffreys, Julius, 1801-1877.
Date:
1822
Catalogue details

Licence: Public Domain Mark

Credit: An inquiry into the comparative forces of the extensor and flexor muscles, connected with the joints of the human body / [Julius Jeffreys]. Source: Wellcome Collection.

    39/58 page 33
    the same time, either stretched forth, or raised above the head ; great weal ness is often felt in the back and loins, much greater than the same weight placed on the back would produce. Does not the cause of this weakness arise from the extensors of the spine lacking the assistance of these muscles ? for did they act, they must greatly tend to draw down the arms, which have to support the weight. The Quadrat! lumborum follow these, and are powerful muscles. The’ Spinales, and Semispinales dorsi, part of the Tra- pezii, the Multifidus Spinse, and the Interspinales, and Intertransversales dorsi et lumborum, are the remaining extensors of the spine. It is no way necessary to treat of these muscles singly, as they correspond to those of the neck, and what has been observed respecting their action there, is also applicable here. With respect to the comparative forces of the muscles of the back and loins, it appears to me, we are brought to the same conclusion as in the neck ;—that the extensors are more powerful than D
    digitised image 1
    digitised image 2
    digitised image 3