Citation:
Wu YX, Tao ZY, Xu ZR, et al. Correlation between pen-holding posture, grip strength and myopia in school-aged children[J]. Chin J Exp Ophthalmol,2024,42(9):827-833. DOI: 10.3760/cma.j.cn115989-20220929-00462.
ABSTRACT [Download PDF] [Read Full Text]
Objective To investigate the correlation between pen-holding posture, grip strength and myopia.
Methods A cross-sectional study was performed.A total of 496 school-aged children in grades 1-6, who underwent eye examinations at Shenzhen Eye Hospital from November 2021 to May 2022 were consecutively enrolled as subjects.The subjects’ age, grade, sex, refractive error and age of school enrollment were recorded.Subjects’ grip strength and pen-holding posture were obtained with an electronic grip strength meter and a tool pen, and subjects were divided into correct pen-holding posture group and incorrect pen-holding posture group according to their pen-holding posture.Propensity scores for sex, grade, age at school entry, and grip strength in the two groups were matched using the nearest neighbor matching method.Multifactorial binary logistic regression analysis was performed with binocular myopia, monocular myopia, and emmetropia as dependent variables and grip strength, grade, refractive error, and pen-holding posture as independent variables.The correlation between grip strength and spherical equivalent was examined by Spearman rank correlation analysis and partial correlation analysis.This study protocol adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Shenzhen Eye Hospital (No.2022KYPJ032).
Results After matching propensity scores, there were 101 cases and 197 cases in the correct pen-holding posture group and incorrect pen-holding posture group, respectively.There was no statistical significance in sex, grade, age at enrollment, and grip strength between the two groups (all at P>0.05).Multinomial logistic regression results showed that using emmetropia as a reference, higher grade (4 versus 1∶7.601[1.307-44.206]; 5 versus 1∶4.392[1.039-18.562]), presence of anisometropia (21.366[5.750-79.397]) were relative risk factors for monocular myopia (all at P<0.05), and higher grade (3 versus 1∶4.389[1.783-10.800]); 4 versus 1∶15.398[3.267-72.574]; 5 versus 1∶7.447[2.232-24.851]; 6 versus 1∶6.462[2.116-19.734]) were relative risk factors for binocular myopia (all at P<0.05).Taking monocular myopia as a reference, higher grade (6 versus 1∶4.582[1.193-17.589]), presence of anisometropia (0.141[0.069-0.289]), and irregular pen-holding posture (2.608[1.340-5.075]) were associated factors for binocular myopia (all at P<0.05).According to partial correlation analysis, the spherical equivalent of the right eye of children with incorrect pen-holding posture was negatively correlated with the grip strength ( r s=-0.141, P=0.047).
Conclusions There is an association between pen-holding posture and myopia in school-aged children.Children with greater grip strength and incorrect pen-holding posture may have higher degrees of right eye refractive error.