evaluation of sole arech index and non-contact lower-extremity injury rates in male karateka

background: the purpose of this study was to determine changes in sole arch index and their effects on non-contact lower-extremity injury rates among male karateka. materials and methods: forty-five male karateka with knee or ankle injuries were chosen from 288 male athletes attending 6 athletic clubs in kerman-iran. injury-related data were collected via a data recording sheet and sole arch index was measured through chippaux-smirak index (csi) method. t-student and chi-square tests were used for statistical analysis of data.   results: the study’s results showed that the most frequent location and time of injury were respectively in knee joint (62.2%) and during training sessions (82.3%). the severity of injuries was minor (57.8%) in most cases. moreover, sole arch index in right leg was abnormal in 68/9% of subjects while 31.1% of them had a normal index in that leg. when left leg was concerned, abnormal and normal indices was evident in 77.8% and 22.2% of subjects respectively. in general, highest percentage of abnormal sole arch index was found in left leg (77.8%). statistical analysis of data by chi-square test demonstrated that there is no relationship between sole arch index in right and left legs. again, application of chi-square test to obtained data showed that there is no relationship between sole arch index and severity of injury. in addition, statistical data analysis through t-test was indicated that there is a significant difference between noncontact lower extremity injury rates when sole arch index is considered (p>0.05). conclusion: according to the results of this study, abnormal sole arch index may significantly affect non-contact lower-extremity injury rates in male karate athletes. key words: non-contact injury mechanism, deformity, sole arch index, csi method.