dysmenorrhea is a gynecological disease which is most common among females with no 
 relevance to ethnicity1 . the prevalence of 
 dysmenorrhea has been reported as 70% in women who menstruate and it is characterized by 
 pain at the onset of menses which lasts for 4872 hours2 . anders c et al . reported that 15% of those who had dysmenorrhea 
 experienced inconvenience in their daily life e.g. absence from school and work3 . in general , dysmenorrhea is related to 
 early menarche , nulliparity , and stress4,5,6 . it 
 has symptoms of aching and numbness of the upper part of the pubis , the hip , the abdomen and 
 thighs , as well as nausea , vomiting , diarrhea , headaches , and lethargy7 , 8 . regarding 
 physiological mechanism of dysmenorrhea , it is well - established that an increase of activity 
 in the uterus which decreases blood flow , and prostaglandin and vasopressin hormones are 
 also associated with dysmenorrhea as well9 . excessive releases of prostaglandin cause excessive contraction of 
 the endometriosis and excessive pressure within the uterus causing menstrual pain10 , 11 . also , based on its ethology , gender w et al.12 proposed that the level of tension in the ligaments and 
 nerves connecting the sacral vertebrae and the uterus is the cause of the pain . this was 
 confirmed by lim c et al.13 who reported 
 that kinesio taping could alleviate the pain intensity of the subjects with painful 
 menstruation . despite these studies , therefore the purpose of this research was to 
 investigate the relationship between pelvic alignment and dysmenorrhea . this research studied 102 females living in busan city whose ages ranged from 10 to 
 40  years old . moos means of measuring premenstrual syndromes ( pms ) , and the menstrual distress 
 questionnaire ( mdq ) were edited and complemented to fit the research purpose . a total of 40 
 questions were used to check various aspects of the menstrual pains experienced by : 3 
 categories referring to attributes related to menstruation ( 5 questions ) , pms ( 23 
 questions ) , menstrual pain questions . the researchers directly explained the purpose of the 
 research , and only distributed the questionnaires to those who agreed to cooperate . the 
 criteria for inclusion in this study were : subjects who gave their informed consent and had 
 a regular menstrual cycle ( 287 days ) . the criteria for exclusion in this study were : a 
 history of gynecological interventions and having received manipulative treatment within the 
 2 months before the beginning of the study , showing any stress or fear of the formetric 4d 
 camera . all participants signed an informed consent form before the beginning of the study , 
 which was approved by the institutional review board of the catholic university of pusan 
 ( cupirb-2015 - 013 ) , and the study was conducted in accordance with the ethical principles of 
 the declaration of helsinki , good clinical practices , and applicable laws and 
 regulations . to analyze the form of the spine , a formetric 4d ( germany , 2010 ) was used to measure trunk 
 imbalance , pelvic tilt , pelvic torsion , surface rotation , lateral deviation , kyphosis angle , 
 and lordosis angle . each subject was stood 180  cm from the formetric camera facing away from 
 it . the test was done with a bare chest , and in order to sense the c7 and psis accurately , 
 the subjects slightly lowered their heads and maintained that position for 5 seconds while 
 all the measurements were being taken . the numerical value of pain of the subjects was assessed using a visual analog scale ( vas ) . subjects with a pain value of vas 8 or over were classified as having menstrual pain ( n=44 ) , 
 and those who had a value less than 8 as otherwise ( n=58 ) . for data the independent samples t - test was used to compare the general attributes of the 
 two groups of with and without menstrual pain . trunk imbalance , pelvic tilt , pelvic torsion , surface 
 rotation , lateral deviation , kyphosis angle , lordosis angle were compared and analyzed using 
 the independent samples t - test . the general attributes of subjects with and without menstrual pain are shown in table 1table 1.characteristics of the subjects ( n = 102)group i ( n=44)group ii ( n=58)age ( years)23.89.225.79.6height ( cm)154.634.4160.321.8weight ( kg)50.011.952.98.7 . the trunk imbalance of subjects who had menstrual pain was 8.86.4  mm , and 
 that of those who did nt have was 9.010.2  mm . those who did nt have menstrual pain had a 
 greater degree of trunk imbalance , but statistically the difference was not significant . the 
 pelvic tilt of the subjects with and without menstrual pain were , respectively 4.13.7  mm 
 and 3.93.8  mm , but the difference was not statistically significant . however , the pelvic 
 torsion of subjects with menstrual pain was 2.41.8and that of subjects without was 
 1.71.1 , significant ( p<0.05 ) . the surface rotation of subjects with menstrual pain was 
 4.01.7 and that of those without was 3.61.6 , with no significant difference . also , the 
 lateral deviation of subjects with menstrual pain was 5.32.4  mm and that of those without 
 was 5.04.1  mm , with no significant difference . the kyphosis angle of the subjects with 
 menstrual pain was 41.110.2 and that of those without was 42.58.6 , with no significant 
 difference ; and the lordosis angle of subjects with menstrual pain was 37.48.0 and that of 
 those without was 35.68.6 , with no significant difference ( table 2table 2 .comparison of the trunk and pelvic alignment between the groupsgroup i ( n=44)group ii ( n=58)trunk imbalance ( mm)8.86.49.010.2pelvic tilt ( mm)4.13.73.93.8pelvic torsion (  ) 2.41.8 * 1.71.1surface rotation ( )4.01.73.61.6lateral deviation ( mm)5.32.45.04.1kyphosis angle ( )41.110.242.58.6lordosis angle ( )37.48.035.68.6meansd , * p<0.05 ) . the percentages of the body regions experiencing pain of vas 8.0 or higher 
 were : lower abdomen , 61.4% ; waist , 50% ; pelvic floor , 9.1% ; headache , 6.8% ; and side , 
 2.3% . this study compared and analyzed the pelvic alignment of 44 subjects who had menstrual pain 
 and 58 subjects who did not . the results show that women with menstrual pain on average had 
 an 8.86.4  mm trunk imbalance , a 4.13.7  mm pelvic tilt , a 4.01.7 surface rotation , a 
 5.32.4  mm lateral deviation , a 37.48.0 lordosis angle , and a 41.110.2 kyphosis angle ; 
 and the subjects who did not have menstrual pain had a 9.0410.2  mm trunk imbalance , a 
 3.93.8  mm pelvic tilt , a 3.61.6 surface rotation , a 5.04.1  mm lateral deviation , a 
 35.68.6 lordosis angle , and a 42.58.6 kyphosis angle . however , the pelvic torsion of subjects who had menstrual pain 
 was 2.41.8 , and that of those who did nt was 1.71.1 , and the subjects who had menstrual 
 pain had a statistically higher value . reported that due to the abnormal 
 restriction of movement of the lumbosacral vertebrae , body fluid increases within the pelvis 
 as well as contraction of the uterus leading to the intensification of the menstrual 
 pain14 . similarly , women who showed an 
 imbalance of the pelvis also experienced greater pain . a possible explanation for this is 
 that the change in the position of the uterus , due to the imbalance of the pelvis , prompted 
 an excessive amount of prostaglandin to be secreted . reported that when the 
 spinal alignment of women who had intense menstrual pain was put back to normal , the pain 
 was alleviated15 . they speculated that 
 somesthesia stimulated by spinal segment motion elicited changes in the activity of the 
 internal organs which relieved the menstrual pain . therefore , it is our opinion that 
 subjects who had higher pelvic torsion had menstrual pain because their spinal alignment was 
 maladjusted . also , the subjects of this research had a high rate of pain in the waist and 
 lower abdomen , respectively 50% and 61.4% . this was possibly due to an abnormal state of the 
 pelvis eliciting an imbalance in the amounts of the hormones , oxytocin and prostaglandin . 
 despite the result , there are some limitations to this research . first , the factors of the 
 subjects everyday life habits , such as smoking , alcohol consumption , medication , and 
 amounts of exercise were not controlled . second , although the subjects comprised a diverse 
 group of people aged from 2040 years old , the distribution between the age groups was not 
 even . this acted as a limitation factor of this research . in future research these 
 limitations should be addressed to improve the quality of the data and the analysis . in conclusion , the results show that there was a significant difference in pelvic torsion 
 between subjects who had menstrual pain and subjects who did not .
[ purpose ] the purpose of this study was to investigate the relationship between pelvic 
 alignment and dysmenorrhea in general women . [ subjects and methods ] one hundred two 
 females participated in this study . 
 they were divided into a dysmenorrhea group and a 
 normal group based on the results of a visual analogue scale ( vas ) assessment of pain and 
 the menstrual distress questionnaire ( mdq ) . 
 the survey data was collecting from 5th july 
 to 20th september , 2014 . 
 formetric 4d was used to measure the pelvic alignment , including 
 the values of trunk imbalance , pelvic tilt , surface rotation , lateral deviation , kyphosis 
 angle , lordosis angle . 
 [ results ] there was a difference in the spine alignments of each 
 group . the value of pelvic torsion was 2.4  1.8 degree in those with dysmenorrhea , while 
 it was 1.7  1.1 degree in those without . 
 [ conclusion ] in conclusion , the results suggest 
 that there is a relationship between menstrual pain and pelvic torsion .