Bone mineral density of the metatarsal bones and the first ray in male sportsmen

Objectives: Measurement of bone mineral density (BMD) is used frequently for assessment of bone strength and prediction of fracture risk in clinical settings. Among the bones in feet, fractures are seen often in second and third metatarsal of active sportsmen. This study was carried out to evaluate the reasons of increased risk of stress fractures in feet of active sportsmen by determining the BMD in overused regions.Methods: Two groups were examined in the present study. First group included males who were not sportsmen while the second and third groups were formed by professional male soccer and basketball players respectively. Areal bone density was measured by dual energy x-ray absorptiometry and the BMD values were calculated by using the rectangular region of interest in metatarsals.Results: The first metatarsal had the highest BMD in all groups (P<0.05). The fifth metatarsal had the second highest BMD value. Similarly subchondral measurement of the BMD revealed that the first tarsometatarsal joint were significantly denser than the first metatarsophalangeal joint (P<0.05). BMDs of all metatarsals in non-sportsmen group were significantly lower than BMDs of sportsmen groups and there were no noticable differences of BMD between soccer and basketball players.Conclusion: Because the degree of activity–induced enhancement of bone mineralization were similar in all metatarsals of active sportsmen, increased incidence of fractures in second and third metatarsals must be partly due to anatomical positioning of these bones. Hence appropriate shoe designs which have support for second and third metatarsals may decrease fracture incidence.