Fracture in children is a significant public health issue and a frequent cause of emergency room visits; its diagnosis and treatment are distinctive. WHO declared the COVID-19 outbreak, caused by severe acute respiratory syndrome coronavirus 2, to be a pandemic on March 11, 2020. In order to curb spread of COVID-19, the Chinese government decided to close the school and encouraged people to stay at home [5]. Stay-at-home orders resulted in a significant reduction in the number of admitted children with fractures compared to the same period in 2017–2019. There were 5346 patients with 6066 fractures that happened in 2017–2019 and 862 patients with 1034 fractures happened in 2020. The reduction in the number of children with fractures might be attributable to the following reasons: 1. Sport and game-playing contributed to a large proportion of fracture events in children. Home confinement reduced the opportunities for physical activity among children, particularly for children living in small apartments in urban areas, which ultimately reduced the risk of fractures [6, 7]. 2.During the epidemic, the children stayed with their parents all day; parental supervision of children was strengthened, which could prevent children from injury in time [8]. 3. Chinese government enforced the restriction of public transport, leading to a decline in traffic accidents, which subsequently reduced the accidents-associated fractures in children.
The fractures ratio in this study was higher than previous researches [2], which might be due to the fact that many children with low-energy trauma that did not cause fractures were treated in primary-level hospitals. Most fractures in older children occurred outdoors; home confinement could reduce the out-door activities, which subsequently resulted in a dramatic decline in the fracture ratio among school children and adolescents in 2020. During home isolation, the number of patients requiring operation treatment was decreased [9].
The patients in 2020 were younger than those in 2017–2019; the main reason was that the activity space of younger children, such as infants and pre-school children, is smaller than that of older children, and the daily activities of younger children are not significantly reduced. The incidence of fractures due to physical activity and sports increases with age; there was a greater impact on the incidence of older children’s fractures than younger children, leading to the old patients significantly reduced in 2020 and the mean age declined.
Previous studies have shown that male children were more prone to fractures than female [10]; however, our study indicated only marginal difference, 58.35% in boys compared to 41.65% in girls in 2020. Most scholars believed the underlying cause reason of more fractures in boys is due to their relatively higher-level activity and their interests of taking risks, which may easily lead to the onset of fractures [11,12,13]. We supposed that the restrictions on boys’ activities under home quarantine were more evident than that of girls’, leading to lower sex ratio (males to females) and lower fractures ratio in boys in 2020.
The number of patients in both 2017–2019 and 2020 reached the peak at the age of 2 to 4 years, and that number in pre-school children was even higher than in school children in 2020. It is mainly due to the intense curiosity of pre-school children, who have the sense of self-action, but the poor ability of risk assessment and self-protection. Therefore, parents should take good care of children between 2 and 4 years old, even during the home isolation. Parents’ awareness of preventing children from injury prevention have a positive effect on lowering the risk of children injuries at home [3]. The age distribution of fractures of this study was different to patterns observed in Europe/North American which usually peaking during puberty [10], the main reason was that most teenagers go to adult hospitals for treatment and we couldn’t get the data of these patients.
Home isolation seems to not impact the severity and site of fractures, and the surgery requirement. The upper limb fractures were still the most common type in children, which is consistent with most published literature [1]. Home isolation narrowed the child’s activity space, which made the child more vulnerable to head injuries. Resulted in the proportion of skull fracture in 2020 was higher than in 2017–2019 (X2 = 69.999, P < 0.001), The incidence of traffic accidents-associated fractures in children was reduced due to the traffic restriction, and falling on the same plane was still the most common cause. Even during home isolation, there were still a large number of children who suffered fractures as a result of falls, and the proportion was even higher than in previous years. Therefore, the supervision of children even during home isolation should not be relaxed.
The social distancing and stay-at-home orders, it leaded to a significant decrease in the amount of activity of the children. The risk of childhood obesity is significantly increased due to lack of activity and obesity in children way lead to decreased bone density [14, 15]. International physical activity guidelines for children recommend that children should participate in at least 60 min of moderate or vigorous physical activity every day [16]. Although physical activity makes children at high risk of fractures; however, in the long run increased physical activity is associated with decreased fracture risk, probably in part due to beneficial gains in areal bone mineral density (aBMD) and muscle strength [1, 17]. We recommend appropriate exercise for children while ensuring safety during the home confinement.
According to researches, pediatric fractures had apparent seasonal rhythm, and the incidence is higher in summer and autumn [2]. It was summer when home confinement end, and the school reopened, children cannot wait to play and exercise after a long period of activity restrictions. It could be anticipated that once the home confinement ends, the incidence of pediatric fractures may be significantly increased. Home isolation leaded to a decrease in the incidence of fractures in children, but the number of children with fractures was still considerable, teachers and parents are required to strengthen the care of children either at home or in school during home isolation or after. At the same time, the pediatricians should be prepared to admit children with fractures.
Limitations
The main limitation of the study was mainly due to the characteristic of a single-center retrospective study, with a limited sample size. Bias during the research seemed to be unavoidable. We cannot predict the impact of extended home isolation time on children’s fracture epidemiology due to the short period for research data. The epidemiology of fracture in children was influenced by region, race and season; the results of this study might not be generalized to the children all over the world, but still could provide valuable references for the epidemiological changes of fracture in children due to home isolation in other countries, and it is beneficial to the decision and treatment of children’s fracture during home isolation.