Risk factors related with avascular necrosis after internal fixation of femoral neck fractures in children: a systematic review and meta-analysis

BackgroundLess than 1% of children develop femoral neck fractures (FNF), making them uncommon. However, they may have dangerous side effects, like avascular necrosis. Even though several risk factors for postoperative avascular necrosis have been identified, there is still debate regarding them. In this investigation, a meta-analysis was performed to examine the potential causes of postoperative avascular necrosis in children with FNF.MethodsWe conducted a thorough literature search to find risk factors for avascular necrosis (AVN) after internal fixation of pediatric FNF. Until December 2022, we searched several databases, including PubMed, Embase, Cochrane Library, Web of Science, CNKI, Orthosearch, and Sinomed. Software Zotero 6.0 and Stata 17.0 were used to organise and synthesise the data. Finally, a sensitivity and publication bias test was carried out.ResultsOur study includes a total of 15 case-control studies involving 814 patients. The risk of postoperative AVN increased with age at fracture encounter (95% CI: 0.64–1.88, P = 0.0003), initial fracture displacement (95% CI: 1.87–9.54, P = 0.0005), and poor fracture reduction (95% CI:1.95–22.34, P = 0.0024) were risk factors for postoperative AVN. There was no significant relationship between gender and postoperative AVN (95% CI: 0.52–1.31, P = 0.41). Conversely, Postoperative AVN and reduction methods have no connection with each other (95% CI: 0.77–2.66, P = 0.25), procedure time (95% CI: 0.43–2.99, P = 0.16), or injury mechanism (95% CI: 0.32–2.26, P = 0.75). The incidence of post-operative AVN varies between Delbet fracture types (95% CI: 0.15–0.31, P