To our knowledge, this study is the first to compare the effects of COVID-19 on open limbs fractures during the no-risk, high-risk and low-risk periods.
There is currently no uniform definition of risk level. However, according to the Chinese government website (http://bmfw.www.gov.cn/yqfxdjcx/), high risk refers to the cumulative number of COVID-19 cases exceeding 50 or a cluster of pandemics occurring within 14 days. Low risk refers to no confirmed COVID-19 cases or no new cases within 14 consecutive days. The primary basis is that the most prolonged incubation period of COVID-19 is 14 days. In Sichuan Province, the first-level response of pandemic prevention and control was launched on January 24, 2020. Until March 24, 2020, the level lowered to the third. Therefore, this study defined the period from January 24 to March 24 as a high-risk period.
During the high-risk period, transportation and residential areas adopt restrictive and isolation measures. However, during the low-risk period, the restrictions on traffic were lifted, and regular life order was fully restored. Moreover, the nucleic acid test has gradually sped up, reducing the waiting time for admission. An epidemiological history and a throat swab of a COVID-19 nucleic acid negative result within seven days need to be provided.
Compared with 2019, the total number of patients in 2020 has declined, especially in severe open fractures and long bone fractures of the lower limbs, consistent with data from a British study . A possible explanation could be the traffic control, factory shutdowns, and agricultural production pauses in lockdown. Under normal circumstances, high-violence injuries, such as traffic injuries and power tools-related injuries are the leading causes of open limbs fractures. We found an increase in both sharp injuries and hand trauma in 2020, compared with 2019 and 2021, even though there was no statistical difference. This growth is likely related to the long-time daily life of people in isolation at home (such as cooking, fruit cutting, woodworking, etc.), in line with recent literature by Pichard et al. . Their study suggested that the primary cause of hand injuries during lockdown was also domestic accidents. Finally, our study observed a significant percentage increase in the total number of patients in 2021, compared to 2019. This growth was probably due to the lack of skills as people have not worked for a long time, and the rush to work to a deadline leading to increased errors.
From the distribution of patients in tertiary trauma centres, we observed that the total number of patients showed a clear "J"-shaped change from 2019 to 2021. However, fewer patients visited the highest level I trauma centre, whereas more patients visited the level II and III trauma centres during the high-risk period. This trend continued and strengthened in the low-risk period. It is suggested that during the pandemic period, the priority treatment strategy for patients with open fractures was to choose the nearest clinic instead of a faraway highest-level medical institution. There may be one reason behind this. Nearby treatment can effectively reduce the flow and gathering of people, thus avoid exposure to COVID-19. Therefore, except for severe open fractures, other mild patients tend to choose the nearby hospital.
Multiple studies suggest that the meantime from injury to surgery was prolonged during lockdown[8–10]. In a study in India, the author found that the time from injury to the emergency department was greatly extended. The reason may have been isolation measures. However, the time from hospital admission to surgery did not change significantly. In contrast, although without statistical significance, we found that the time from injury to emergency department shortened, whereas the time from admission to surgery dramatically extended in the high-risk period. This finding suggested that prevention and control measures in different countries may extend the preoperative waiting time. The difference was that some rose the pre-hospital first aid time, while others improved the in-hospital first aid time.
Although the infection rate and 30-day readmission rate in this study did not increase significantly in 2020, it is undoubtedly worth encouraging the reduction of waiting time preoperatively. Therefore, we suggest that different countries formulate strategies based on their actual conditions, such as simplifying procedures, accelerating nucleic acid testing, and opening rapid channels. It should be emphasized that these strategies still need to be based on a set of guidelines for screening potential patients with COVID-19.
In terms of the definite wound closure type, patients in the high-risk period are more often covered by direct closure. This phenomenon may be related to the high percentage of G-A I, II, and IIIa grading during this period (totally 71%). These three levels are prone to direct closure. In terms of the duration of antibiotic application, the proportion of therapeutic use of antibiotics (actual medication time > 48h) in 2021 has increased significantly compared with that in previous periods. This change was most likely due to surgeon’s concern about repeated debridement surgery. Besides, guidance to surgeons for COVID-19 stated that “alternative techniques [should be considered] for patients who require soft tissue reconstruction to avoid multiple operations or the need for critical care input”.
The fight against the COVID-19 is still the most pressing problem facing various countries. It is recommended that when formulating prevention and control measures in the future, decision-makers should conduct comprehensive evaluations from multiple dimensions such as the proportion of patients in the total population, the growth rate of local cases or the rate of spread of the disease, the proportion of vaccination, and the prevention. It helps to avoid two extreme mistakes. The first is to weaken the prevention and control measures in advance before the pandemic is effectively controlled, resulting in a counterattack or "second wave" of the pandemic. The second is to adopt high-level measures when the pandemic is already at a low-risk period. Intensive preventive measures and isolate management would cause an inconvenience on people’s lives, waste medical resources and result in a long-term social and economic downturn.
The strengths of this study include the comparison of the COVID-19 lockdown cohort into two separate control groups, thus reducing the effect of seasonal variation in the patterns of patient presentation. Moreover, this study is a multi-centre study, thus reducing the potentially generating sampling bias. There are several limitations in the present study. First, this study is a retrospective cohort study. Second, there was only one hospital representing each level of the three-level trauma system. Third, the total number of included cases is insufficient. Fourth, the impact of patient-related factors, such as smoking, alcohol habits, concomitant internal disease, is unclear.