The incidence and pattern of fractures in children under two years of age

Abstract

Abstract

The literature on fracture incidence and patterns in children under two years of age is sparse; thus, we set out to examine this. In addition, we estimated the occurrence of suspected inflicted injury, and its association with radiological “red flags”.

Material and methods: Retrospective, population based cross-sectional study, including all children under two years of age who presented at the A&E department at the University hospital in Tromsø due to a trauma warranting radiographic examination between January 1st, 2010, and December 31st, 2023. Patients were identified through searches in the PACS system. In addition to demographic data, we registered the number of days between the trauma, and the first radiographic examination, and mechanism of injury, as provided by the caretaker(s) / birth injury, whether an additional skeletal survey was performed, and if so, if there were any findings. All the radiographs were reviewed by the researchers. In accordance with established practice, an ethics committee review was not required (Regional Ethics committee (REK-N), number 2012/172). Data handling and storage were performed in accordance with the relevant guidelines and regulations and approved by the local data protection officer (PVO; 2024/4625-2).

Results: A total of 430 children (49.8% female) under the age of two, mean age 14.7 months (SD 6.8), were included, of whom 4 children sustained a high-energy trauma and 42 sustained a birth related trauma. No significant differences in the number of injuries (p=0.76) or fractures (p=0.84) were observed according to gender.

Of the 388 children (50.3% female) (mean age 16.3 months, SD 5.1 months) with a non-birth related injury, 163 (42.0%) had a fracture, yielding an annual incidence of 4.3 per 1,000 children under the age of two. Infants had a significantly lower annual incidence as compared to children between 12 and 24 months of age (2.4 per 1,000 vs. 6.1 per 1,000, p = 0.01).

Fracture mechanisms for the 388 non-birth related injuries were, in declining order, 93 (23.9%) fall from more than own height/furniture; 67 (17.2%) fall from own height, 61 (15.7%) crush injury and 41 (10.6%) stretch/pull trauma. Notably, 53 (13.6%) injuries had an unknown mechanism. In 8 (2%) of the cases, no information on mechanism was available in the clinical journal.

47 of the 163 fractures (28.7%) involved the forearm while 40 (24.5%) were fractures to the leg. The number of fractures increased significantly by age group, with 6 (3.7%) fractures seen amongst 0-6-months-olds, 30 (18.4%) in those aged 6-12 months, 60 (36.8%) in the 12-18-months-olds and 64 (39.3%) in the 18-24-months-olds (p=0.039). No classic metaphyseal lesions were seen. The distribution of fractures differed according to age group, with skull fractures predominating in 0-6-months-olds (33.0%), clavicle fractures (33.0%) in 6-12-months-olds and forearm fractures in the two oldest age groups (35.0% and 34.4%, respectively) (p < 0.001). Four children sustaining a fracture, all of whom had radiological “red flags”, were subsequently diagnosed with inflicted injury by the Child Protection Services.

42 children sustained a birth-related injury, of whom 21 (50.0%) had a fracture, yielding a fracture-incidence of 1.1 per 1,000 live births. Fractures to the clavicle and humerus were the two most common locations.

Conclusion: Injuries and fractures in children under two years of age are rare, particularly in infants. The occurrence of classic metaphyseal injuries, or radiological “red flags” should raise suspicion of non-accidental injury and instigate further assessment.

Abstract

The literature on fracture incidence and patterns in children under two years of age is sparse; thus, we set out to examine this. In addition, we estimated the occurrence of suspected inflicted injury, and its association with radiological “red flags”.

Material and methods: Retrospective, population based cross-sectional study, including all children under two years of age who presented at the A&E department at the University hospital in Tromsø due to a trauma warranting radiographic examination between January 1st, 2010, and December 31st, 2023. Patients were identified through searches in the PACS system. In addition to demographic data, we registered the number of days between the trauma, and the first radiographic examination, and mechanism of injury, as provided by the caretaker(s) / birth injury, whether an additional skeletal survey was performed, and if so, if there were any findings. All the radiographs were reviewed by the researchers. In accordance with established practice, an ethics committee review was not required (Regional Ethics committee (REK-N), number 2012/172). Data handling and storage were performed in accordance with the relevant guidelines and regulations and approved by the local data protection officer (PVO; 2024/4625-2).

Results: A total of 430 children (49.8% female) under the age of two, mean age 14.7 months (SD 6.8), were included, of whom 4 children sustained a high-energy trauma and 42 sustained a birth related trauma. No significant differences in the number of injuries (p=0.76) or fractures (p=0.84) were observed according to gender.

Of the 388 children (50.3% female) (mean age 16.3 months, SD 5.1 months) with a non-birth related injury, 163 (42.0%) had a fracture, yielding an annual incidence of 4.3 per 1,000 children under the age of two. Infants had a significantly lower annual incidence as compared to children between 12 and 24 months of age (2.4 per 1,000 vs. 6.1 per 1,000, p = 0.01).

Fracture mechanisms for the 388 non-birth related injuries were, in declining order, 93 (23.9%) fall from more than own height/furniture; 67 (17.2%) fall from own height, 61 (15.7%) crush injury and 41 (10.6%) stretch/pull trauma. Notably, 53 (13.6%) injuries had an unknown mechanism. In 8 (2%) of the cases, no information on mechanism was available in the clinical journal.

47 of the 163 fractures (28.7%) involved the forearm while 40 (24.5%) were fractures to the leg. The number of fractures increased significantly by age group, with 6 (3.7%) fractures seen amongst 0-6-months-olds, 30 (18.4%) in those aged 6-12 months, 60 (36.8%) in the 12-18-months-olds and 64 (39.3%) in the 18-24-months-olds (p=0.039). No classic metaphyseal lesions were seen. The distribution of fractures differed according to age group, with skull fractures predominating in 0-6-months-olds (33.0%), clavicle fractures (33.0%) in 6-12-months-olds and forearm fractures in the two oldest age groups (35.0% and 34.4%, respectively) (p < 0.001). Four children sustaining a fracture, all of whom had radiological “red flags”, were subsequently diagnosed with inflicted injury by the Child Protection Services.

42 children sustained a birth-related injury, of whom 21 (50.0%) had a fracture, yielding a fracture-incidence of 1.1 per 1,000 live births. Fractures to the clavicle and humerus were the two most common locations.

Conclusion: Injuries and fractures in children under two years of age are rare, particularly in infants. The occurrence of classic metaphyseal injuries, or radiological “red flags” should raise suspicion of non-accidental injury and instigate further assessment.