Body Weight at Birth: The Only Risk Factor Associated with Contralateral Clavicular Fracture in Patients with Congenital Muscular Torticollis

To date and to the best of our knowledge, there have been limited studies on the risk factor of clavicle fracture combined with congenital muscular torticollis (CMT), despite it being the most common fracture in newborns. So, the aim of this study was to investigate the risk factors associated with clavicular fracture combined with CMT, and its effect on prognosis. In this study, a total of 134 infants with CMT were included. The risk factors associated with clavicular fracture combined with CMT were analyzed. To analyze the correlation between the clinical parameters and the clavicular fracture in patients with CMT, demographic data, such as body weight at birth, maternal age, gender, gestational age, delivery method, sternocleidomastoid (SCM) thickness of ipsilateral side, its ratio between the ipsilateral and contralateral side, and the first visitation date after birth were evaluated. In the results of this study, the clavicular fracture was found in 15 of 134 patients with CMT (19%). In multivariate logistic analysis, the body weight at birth was the only significant parameter for predicting clavicular fracture in patients with CMT (p-value < 0.05). However, there was no significant difference of treatment duration between CMT infants with or without clavicular fracture. In infants with CMT, the area under the ROC curve of the body weight at birth for predicting clavicular fracture was 0.659 (95% CI, 0.564–0.745.; p < 0.05). The optimal cut-off value obtained from the maximum Youden index J was 3470 g (sensitivity: 57.14%, specificity: 75.76%), and the odd ratio of clavicular fracture in patients with CMT increased by 1.244 times for every 100 g of body weight at birth. In conclusion, birth weight appears to be a clinical predictor of clavicular fracture in infants with CMT. More studies and discussions are needed on whether any screening should be recommended for detecting the concurrent clavicular fracture in subjects with CMT.