Lumbricals of the foot phalanges. All four lumbricals insert into extensor hoods of the phalanges, thus creating extension at the inter-phalangeal (PIP and DIP) joints. However, as the tendons also pass inferior to the metatarsal phalangeal (MTP) joints it creates flexion at this joint. Absence of one or more; doubling of the third or fourth even the fifth. Insertion partly or wholly into the first phalanges. The most medial lumbrical is innervated by the medial plantar nerve while the remaining three lumbricals are supplied by the lateral plantar nerve. Lumbricals of the foot The lumbricals are four small skeletal muscles, accessory to the tendons
Effect of spaceflight on the human body on the bones, there is a rapid increase in bone loss, from 3% cortical bone loss per decade to about 1% every month the body is exposed to microgravity, for an otherwise healthy adult. The rapid change in bone density is dramatic, making bones frail and resulting in symptoms which resemble those of osteoporosis. On Earth, the bones are constantly being shed and regenerated through a well-balanced system which involves signaling of osteoblasts and osteoclasts. These systems are coupled, so that whenever bone is broken down, newly formed layers take its place—neither should happen without the other, in a healthy