Experience with the management of 2599 cases of congenital muscular torticollis and a multicenter epidemiological investigation in 17 hospitals in China
Authors: Zhao Zhenhui , Deng Hansheng , Li Yuanheng , Wang Xinyu , Tang Gen , Zeng Yueping , Xu Hui , Yang Qisong , Wu Zhengyu , Li Shicheng , Cui Zhiwen , Feng Guoshuang , Fu Guibing , Tang Shengping , Xiong Zhu , Qiu Xin ,   Futang Research Center of Pediatric Development(FRCPD), Tian Jian , Song Fei , Xu Xin , Wu Mei , Wang Guosong , Li Li , Sun Hongjie , Da Zhenqiang , Wang WenJuan , He Qinghong , Liu Shaoqian , Dai Ling , Hu Waiguang , Wang Xiaoqin , Du Jian , Wang Chunxiang , Qu Yuanyi , Zhu Daqiao , Ding Jian , Zhou Haibin , Shi Jinchi , Pan Zhijun , Yang Lei , Zhang Tingting , Xu Jin , Ruan Lianjun , Mai Shu , Ma Fengmei , Gao Li , Liu Hongcheng , Chen Xirong , Zhang Yuzheng , Zhou Jun , Yan Chun Xiang , Fang Jian 
Published: November 2023

Abstract
Background
Congenital muscular torticollis (CMT) is a common musculoskeletal disease affecting infants and young children. If CMT is not treated correctly and timely, it can lead to limited head and neck movements, head and neck deviation, and abnormal posture. In order to improve patients' symptoms and alleviate the negative impact of the disease on their lives, we are committed to exploring the treatment of CMT.

Methods
The general clinical and ultrasonographic data of 2599 children with CMT who received standardized treatment at Shenzhen Children’s Hospital from 2004 to 2020 were retrospectively reviewed. According to given treatment, children with CMT were divided into the physiotherapy group, physiotherapy combined with glucocorticoid treatment group, and surgical treatment group. We divided children with CMT into local mass, uniform thickening, and atrophy according to ultrasound features. General clinical information, treatment, and ultrasound examination data in each group were compared. Additionally, electronic medical records of 2344 patients admitted due to CMT in 17 tertiary children’s hospitals of China’s Futang Research Center of Pediatric Development (FRCPD) from 2015 to 2019 were retrospectively analyzed. Data on sex, age, year of admission and discharge, and treatment costs during hospitalization were extracted from the first medical record pages according to the ICD codes. The data were assessed for normality using the Kolmogorov–Smirnov test. Depending on the data distribution, they were analyzed using parametric tests, such as the t-test, or non-parametric tests. Qualitative data are expressed as percentages (%) and analyzed using the chi-square or Fisher’s exact probability test, with α = 0.05 as the test level. P < 0.05 was considered to be indicative of a statistically significant difference.

Results
Three types of CMT were defined based on sternocleidomastoid muscle ultrasound examination characteristics: local mass, uniform thickening, and atrophy. Age at first diagnosis was 69.21 ± 108.41 days in local mass type group, 216.85 ± 324.09 days in uniform thickening group, and 417.88 ± 739.05 days in atrophy- type group; while age at first physiotherapy use was 94.06 ± 206.49 days, 255.00 ± 430.62 days, 540.92 ± 1059.29 respectively. The children included in local mass type group have shown a high success rate of conservative treatment, with a rate of 7.5% of children underwent surgery. Age at first diagnosis was 112.44 ± 224.12 days in the physiotherapy group, 115.87 ± 144.86 days in the physiotherapy combined with glucocorticoid treatment subgroup, whereas the age at first physiotherapy use was 137.38 ± 312.11 and 196.91 ± 344.26 days respectively. In the observation period (2015–2019) the mean age at surgery for CMT in 17 tertiary children’s hospitals of the FRCPD was 50 months. Overall, 663 children with CMT were 1–2 years of age, accounting for the largest proportion (28.3%). Followed by 417 individuals (17.8%) were 7–14 years of age, indicating that there are still more children with CMT receiving surgical treatment later.

Conclusions
Early diagnosis and treatment are essential to improve the conservative treatment success rate and achieve good prognosis in children with CMT. Our team’s concept for treating CMT is as follows: after diagnosing the children, we will adopt the standardized protocol of treatment, with physiotherapy combined with the injection of glucocorticoid drugs and SCM release surgery, when needed. This program has a high conservative treatment success rate and may facilitate the achievement of better prognosis and reduced teratogenicity rate.