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Population-based incidence and demographic patterns of traumatic joint dislocations in children and adolescents
William J Söderling1, Ilkka J Helenius2, Petra M Grahn3
1University of Helsinki, Faculty of Medicine, Helsinki; Department of Orthopaedics and Traumatology, University of Helsinki and Helsinki University Hospital, Helsinki,; Finnish Pediatric Orthopaedics Research Group (FIPO), Helsinki, Finland. william.soderling@hus.fi.
Background And Purpose:
Limited population-based data is available concerning traumatic joint dislocations in children and adolescents. We aimed to determine the incidence, typical locations, and demographic patterns of joint dislocations in a pediatric population.
Methods:
This retrospective, population-based study analyzed pediatric joint dislocations in the Helsinki University Hospital catchment area from 2009 to 2021. Data was retrieved from electronic health records using ICD-10 codes and radiological keywords. Primary radiographs were reviewed to confirm diagnoses. Incidences were calculated using population data, and trends were analyzed by age, sex, and dislocation site. 2,741 traumatic dislocations were included.
Results:
The overall annual incidence of joint dislocations was 69 per 100,000 children, with a higher incidence in boys than in girls (72 vs 66 per 100,000, odds ratio 1.1, 95% confidence interval 1.02-1.2). The peak incidence occurred at 16 years of age for boys and 15 years of age for girls. Patellar (49%), elbow (19%), finger (12%), and glenohumeral (10%) dislocations accounted for 90% of cases with respective mean incidence; 35, 13, 8.4 and 7.1 per 100,000.
Conclusion:
The annual incidence averaged 69 per 100,000 children. Joint dislocations in children predominantly affect the patellar, elbow, finger, and glenohumeral joints, with adolescence being the most vulnerable period.
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