Cause and clinical characteristics of rib fractures in infants

Objective. Rib fractures are uncommon in infancy and, when diagnosed, often raise the suspicion of child abuse. However, the prevalence of other cause s of rib fractures has not been well defined. The purpose of this study was to determine the causes and clinical presentations of rib fractures in inf ants <12 months old. Methods. Retrospectively, we identified all infants with rib fractures unde r 12 months old over a 3-year period using computerized databases at the Ch ildren's Hospital Medical Center in Cincinnati, Ohio and at the Children's Hospital, Winnipeg, Manitoba, Canada. Data extracted from the individual pa tient charts included: age, sex, chief complaint, number and location of ri b fractures, associated injuries, birth history, history of cardiopulmonary resuscitation, and any evidence of bone dysplasia. After the chart review and a review of the radiographs by a pediatric radiologist, all fractures w ere determined to be attributable to one of the following causes: child abu se, birth injury, bone fragility, or accidental trauma. A determination of abuse was made when there were other injuries indicative of abuse, there wa s no clinical or radiographic evidence of bone fragility, there was a confe ssion of abuse, when no reasonable history of trauma was provided, or when the history was not plausible to explain the rib fractures. Standard practi ce at these hospitals involves obtaining skeletal surveys on all children < 2 years old when abuse is suspected. The child abuse team, which consists o f physicians, nurses, and social workers, conducts these investigations and works closely with police in evaluating these children. Results. Thirty-nine infants with rib fractures were identified. Thirty-two (82%) were caused by child abuse. Three (7.7%) were attributable to accide ntal injuries, 1 (2.6%) was secondary to birth trauma, and 3 (7.7%) were at tributable to bone fragility. All 3 infants with fractures from accidental injury had sustained notable trauma (a motor vehicle collision, a forceful direct blow, and a fall from a height). Of the 3 infants with fractures sec ondary to bone fragility, 1 infant had osteogenesis imperfecta, 1 infant ha d tickets, and 1 infant, who was born at 23 weeks' gestation, had fragile b ones attributable to prematurity. Conclusions. Most rib fractures in infants are caused by child abuse. Altho ugh much less common, rib fractures can also occur after serious accidental injuries, birth trauma, or secondary to bone fragility. A thorough clinica l and imaging evaluation is mandatory.