Board Thread:Rebirth: Applications/@comment-4080775-20141205213456/@comment-4080775-20141206143712

Almost al shinobi have 361 tenketsu within their body. Chakra flows through these tenketsu, and its already a manga fact that hitting these points can effectively disrupt and halt the flow of chakra, as shown by Neji Hyuga. Shiro isn't able to manipulate the number of tenketsu she has, so she manipulates their location by manipulating her muscles to her hand, allowing her to form the Rasengan much easier, as she can manipulate the chakra more easily since more tenketsu are present in her hand.