Increasing Trends of Pediatric Thoracic and Lumbar Spine Fractures in the United States from 2004 to 2023: A 20-year National Injury Review Depicting Shifts in Mechanisms of Injury.

BACKGROUND

Fractures of the thoracic and lumbar spine are uncommon injuries in children and adolescents, but they carry substantial morbidity and a real risk of death. Compared with the adult spine, the pediatric spine has unique anatomic and biomechanical properties that yield different fracture patterns than the adult population. The mechanisms of injury and degree of skeletal maturity constitute important predictors of the outcomes of pediatric thoracic and lumbar fractures; however, there remains a paucity of meaningful epidemiologic data with specific attention to the pediatric spine.

QUESTIONS/PURPOSES: (1) What are the overall incidence and trends of all-cause pediatric thoracic and lumbar fractures in the past 20 years, and how do these differ by age and sex? (2) What are the primary mechanisms of injury responsible for all-cause pediatric thoracic and lumbar fractures, and how do these differ by age and sex? (3) What are the sex-specific incidence risks of all-cause pediatric thoracic and lumbar fractures in the past 20 years? (4) What are the age-specific incidence risks of all-cause pediatric thoracic and lumbar fractures in the past 20 years?

METHODS

The National Electronic Injury Surveillance System (NEISS) is a publicly available database from a nationally representative sample of emergency departments that offers key details on mechanisms of injury and a statistically valid calculation method of national injury estimates. The NEISS was retrospectively queried for patients ages 0 to 18 years who presented with all-cause thoracic and lumbar fractures between 2004 and 2023. Thoracic and lumbar fractures were identified from upper trunk and lower trunk fracture NEISS diagnosis codes, filtering out nonpertinent diagnoses such as rib, hip, or pelvis fractures (72% [5853 of 8131]). From relevant thoracic and lumbar fractures, only acute fractures were included after narrative review; chronic or incidental fractures or spondylolysis (0.2% [5 of 2278]) and acute fractures that did not specify an affected thoracic or lumbar region (6% [136 of 2278]) were subsequently excluded. Collected variables included age, sex, hospitalization, primary mechanism of injury, fracture level(s), and fracture type. Each NEISS case record is assigned a statistical weight, representing an estimate of such injury occurring nationally. The aggregate of these weights in patients presenting with a thoracic or lumbar fracture provides a total national estimate of these injuries. Age was subsequently classified into children (younger than 14 years) and adolescents (ages 14 to 18 years). There were 1064 case records of thoracic fractures, 988 case records of lumbar fractures, and 85 case records of thoracic and lumbar fractures between 2004 and 2023, corresponding to a national estimate of 26,732 thoracic fractures, 29,274 lumbar fractures, and 2083 thoracic and lumbar fractures after computing the aggregate statistical weights of the associated case records. Fractures affecting both the thoracic and lumbar spine were included in the separate cohorts of thoracic and lumbar fractures, totaling a final national estimate of 28,814 thoracic fractures and 31,357 lumbar fractures. Of patients with thoracic fractures, 43% (12,264 of 28,814) and 57% (16,550 of 28,814) were children and adolescents, respectively, and 64% (18,328 of 28,814) and 36% (10,486 of 28,814) were male and female, respectively. Of patients with lumbar fractures, 29% (9109 of 31,357) and 71% (22,248 of 31,357) were children and adolescents, respectively, and 61% (19,084 of 31,357) and 39% (12,273 of 31,357) were male and female, respectively. Incidence rates were calculated using provided national estimates and as incidence per population at-risk using US census data. Simple linear regression analysis characterized overall and demographic-specific trends over the 20-year period, with the beta coefficient (β) representing change in fracture national estimates per year. Incidence rate ratios were calculated to compare demographic groups with regard to overall fracture incidence, recreation-related mechanism of injury, multilevel injury, and hospitalizations.

RESULTS

The mean ± SD annual incidence rate over the 20-year study span was 19 ± 6 pediatric thoracic fractures and 20 ± 5 pediatric lumbar fractures per 1 million person-years. There were overall increasing trends in pediatric thoracic fractures by 58 fractures per year (β = 58 [95% confidence interval (CI) 30 to 86]; p < 0.001). Increases in thoracic fractures were noted among males, females, children, and adolescents, with the largest increases in males by 41 fractures per year (β = 41 [95% CI 19 to 63]; p < 0.001) and adolescents by 41 fractures per year (β = 41 [95% CI 19 to 64]; p = 0.001). There were overall increasing trends in pediatric lumbar fractures by 38 fractures per year (β = 38 [95% CI 9 to 67]; p = 0.01), most prominently in males by 30 fractures per year (β = 30 [95% CI 9 to 51]; p = 0.007). These slight yearly increases resulted in substantial total increases in thoracic and lumbar fractures over the 20-year period. Falls from height and motorsports were the most common mechanisms of injury for overall pediatric thoracic and lumbar fractures. Males primarily sustained thoracic and lumbar fractures from motorsports, football, and falls from height, whereas females primarily sustained thoracic and lumbar fractures from falls from height, horseback riding, winter sports, and playground accidents. Children primarily sustained thoracic and lumbar fractures from falls from height and playground accidents, whereas adolescents primarily sustained thoracic and lumbar fractures from motorsports, falls from height, and winter sports. Age- and sex-based differences in motorsports were especially large, with motorsports accounting for nearly fourfold as many fractures in males than in females and more than twofold as many fractures in adolescents than in children. The overall rate of thoracic and lumbar fractures was 1.82 (95% CI 1.77 to 1.86; p < 0.001) and 1.63 (95% CI 1.60 to 1.67; p < 0.001) times higher in males compared with females. The overall rate of thoracic and lumbar fractures was 3.67 (95% CI 3.58 to 3.75; p < 0.001) and 6.69 (95% CI 6.52 to 6.85; p < 0.001) times higher in adolescents compared with children.

CONCLUSION

Our findings suggest that increased public policy attention be directed toward recreational activities such as motorsports and football, which disproportionately affect adolescent males. Formal safety training, strict age requirements, and regulations on the speed and horsepower of all-terrain vehicles and dirt bikes should be considered for motorsports. Similar age limits and introduction of modified tackling and football skills development should be considered prior to full-contact football. It is the responsibility of orthopaedic surgeons to increase public attention on the fracture risk of horseback riding, which has been traditionally perceived to be low risk. Increased barrier protection on bunk beds, windows, staircases, and playground equipment may lower the rate of accidental falls for all demographics.

LEVEL OF EVIDENCE

Level III, prognostic study.