A total of 142 metatarsal bones of unknown age and sex were examined for the length of the bone and number & position of the nutrient foramen. Study also included the direction of nutrient foramina and it's distances from both the ends . It was observed that almost all the Metatarsals had one nutrient foramen in the middle third of their shaft In 5 th Metatarsals majority of foramina were situated on the medial surface whereas in other metatarsals the foramen were mostly situated on the lateral

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... surface. Invariably all foramina were directed away from the growing ends of the bone Keywords: metatarsal, nutrient foramen, nutrient vessel, short long bone I. Introduction The metatarsals are the miniature long bones present in the foot and possess a head distally, a shaft and a base proximally (Standring 2005) [1] . The first metatarsal bone is large, strong and participates in supporting the weight of the body. The fifth metatarsal has a prominent tubercle on its base easily palpable along the lateral border of the foot, gives attachment to the peroneus brevis tendon (Snail 2007) [2] . The metatarsals have a single epiphysis at one end only [3] as opposed to other long bones which do have it at both the ends . The, epiphyses appear for the base of the first metatarsal and for the heads in the remaining metatarsals [3] . The Metatarsal bones are frequently used in minimally invasive surgeries and osteotomies for construction of "Split Metatarsal musculo-osseous flap", in the reconstruction surgery of foot.. When a bone graft is taken, the vascularization of the remaining bones has also to be considered. The vascularity of this area allows various options in grafting [4] . It was reported that the ideal bone graft for the free transfer should include endosteal and periosteal blood supply with good anastomosis (Taylor 1979) [5] . The bony defect, appearing followed by different surgical procedures i.e. tumor resection, trauma repair or pseudoarthrosis needs to be reconstructed by bone grafting procedures. And the the best bone graft is supposed to be free vascularized bone graft (Pho RWH 1988) [6] To prevent complications such as avascular necrosis during the design of minimally invasive surgeries (MIS) carried out on the toe of the foot it is important to know the position of the nutrient foramen in the metatarsal shaft .The nutrient artery of the metatarsal bone is very important during its active growth period as it is the main source of blood . Being the source of nutritional supply it plays an important role in fracture healing and union also (Shrimankar et al. 2010) [7] . The nutrient artery enters the metatarsal bone through nutrient foramen. The topographical knowledge of these foramina in such operative procedures helps in preserving the circulation specially in free vascularized bone grafts, so that the osteoblasts can survive (Green 1988) [8] .. The knowledge about nutrient foramina is important in surgical procedures like utilization of metatarsal bones in the foot reconstruction. Singh (1960) [9] , while studying the variations in the articular facets of metatarsal bones, made some observations on their nutrient foramina. The nutrient foramina of long bones has been studied by many authors (Collipal et al. 2007; Kizilkanat et al. 2007 [10] ; Murlimanju et al. 2011 [11] ; Prashanth et al. 2011 [12] ), but the studies on the nutrient foramina in metatarsals are very few. The directions of the nutrient canals are remarkably constant as it has been explained by different workers in different time period. Where Havers (1691) [13] described the directions of the nutrient canals in the long bones of Various mammals, Berard (1835) [16] correlated the direction of this canal with the mode of ossification and growth of the bone. Clark (1965) explained the obliquity of entrance of nutrient artery into the long bone related with Greater longitudinal growth at the growing end of a bone , and stated that nutrient artery was initially at right angles to the shaft, at its entrance and became oblique later on because of the the deflexion of nutrient artery towards the non-growing end of the bone. Aim of the present investigation was to study the morphometric anatomy of the nutrient foramina in human adult metatarsal bones which included it"s number , location and distance from both ends of bone and whether the nutrient foramina do obey the general rule, i.e. directed away from the growing end. The foramina indexes for the metatarsal l bones were also determined to provide a mathematical method for accurately locating it prior to surgery