| Objective: Hallux valgus is a common disease which not only includes the first metatarsophalangeal joint eversion,but also involves in the foot physiological anatomy and biomechanics,a series of three-dimensional complex abnormalities.Previous literature suggested that imbalance between abductor hallucis(AbdH)muscle and adductor hallucis(AddH)muscle was core factors of hallux valgus,but related studies to explore whether participate in such complex abnormalities were less.So this paper aims to research the relationship between electrophysiological changes of AbdH muscle and the threedimensional complex malformation in hallux valgus through the needle electromyography,and further to study the pathogenesis of hallux valgus and pathological changes to improve the rate of deformity correction.Methods: A total of 30 cases were included in this study including 7 males and 23 females.There were 24 cases of hallux valgus(including 14 cases of unilateral hallux valgus foot,14 cases of unilateral normal foot and 10 cases of bilateral hallux valgus foot),6 cases of voluntary subjects(both bilateral normal foot),and sum to 34 cases of hallux valgus foot and 26 cases of normal foot.The amplitude of AbdH muscle was obtained by needle electromyography,and was compared between normal foot and hallux valgus foot.The angle of hallux valgus(HVA)and the intermetatarsal angle(IMA)were measured on the foot X-ray to show the degree of hallux valgus deformity,and the correlation between the amplitude of AbdH muscle and the deformity degree was analyzed.The forefoot transverse arch index H was used to evaluate the degree of forefoot transverse arch collapse in hallux valgus foot,and the correlation between the degree of hallux valgus deformity and forefoot transverse arch collapse was analyzed.The distance from the center of the lateral sesamoid to the axis of the second metatarsal bone was selected to indicate the degree of sesamoid dislocation,and the correlation between the amplitude of AbdH muscle and the degree of sesamoid dislocation and transverse arch collapse of the forefoot was analyzed.All data analyses were conducted with the use of SPSS 22.0 statistical software.The t-test and Mann-whitney test were used to compare the amplitude difference of abductor hallucis between the hallux valgus group and the normal group.The correlations of the data were tested using Pearson or Spearman correlation analysis and the test level was 0.05.Results: The amplitude of AbdH muscle in normal foot was higher than hallux valgus foot,and the difference was statistically significant(P=0.000).There was no significant correlation between the age of hallux valgus patients and the transverse arch index H(Pearson test P=0.213,Spearman test P=0.136).There was no significant correlation between transverse arch index H and body weight in hallux valgus patients(P=0.096,P=0.200).The degree of hallux valgus deformity(HVA)was negatively correlated with the transverse arch index H(P=0.001,R=-0.558;P=0.000,R=-0.633);The degree of hallux valgus deformity(IMA)was negatively correlated with the transverse arch index H of forefoot(P=0.000,R=-0.702;P=0.000,R=-0.615);The amplitude of AbdH muscle was positively correlated with forefoot transverse arch index(P=0.000,R=0.625;P=0.000,R=0.608);There was no significant correlation between the amplitude of AbdH muscle and the degree of hallux valgus deformity(HVA/IMA)(P=0.242,P=0.063).There was no significant correlation between the amplitude of AbdH muscle and the degree of sesamoid dislocation(P=0.846,P=0.947).Conclusion: 1.The AbdH muscle of hallux valgus foot not only changes in anatomical position,but also in physiological function or morphology.However,there was no significant correlation between the changes and the degree of deformity,so the changes of AbdH function may occur in the period before the clinical symptoms of hallux valgus deformity or in the early stage of malformation.2.The transverse arch of the forefoot plays a role in absorbing shock and cushioning the plantar pressure.The aggravated hallux valgus deformity can lead to the widening of the forefoot,the collapse of the transverse arch,and the sinking of the second and third metatarsal.3.The changes of AbdH function not obviously affect the degree of sesamoid dislocation.During the progression of hallux valgus deformity,the distance between the lateral sesamoid and the second metatarsal may be unchanged.4.Previous studies suggested that AddH muscle play an important role on foot cross bow.We find that AbdH muscle is related to transverse arch,and further confirmed previous literature based on the imaging and anatomy.The AbdH muscle also involved in maintaining transverse arch,which may be combined with flexor hallucis brevis and flexor digitorum brevis,or integrated with AddH muscle through the sesamoid system to maintain forefoot arch. |
PDF Full Text Request