Metatarsal bones the metatarsals are the bones most often involved. These fractures are sometimes called march fractures, based on their traditional association with military recruits after long marches. The second and third metatarsals are fixed while walking, thus these metatarsals are common sites of injury. The fifth metatarsal may be fractured if the foot is oversupinated during locomotion. Protection from injuries can be given by the use of safety footwear which can use built-in or removable metatarsal guards. Metatarsal bones The metatarsal bones, or metatarsus are a group of five long bones in the foot, located between the tarsal bones of the
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