Growth recovery lines are more common in infants at high vs. low risk for abuse.

BACKGROUND

Growth recovery lines, also known as growth arrest lines, are transverse radiodense metaphyseal bands that develop due to a temporary arrest of endochondral ossification caused by local or systemic insults.

OBJECTIVE

To determine if growth recovery lines are more common in infants at high risk versus low risk for abuse.

MATERIALS AND

METHODS

Reports of American College of Radiology compliant skeletal surveys (1999-2013) were reviewed with clinical records. Infants at low risk for abuse had a skull fracture without significant intracranial injury, history of a fall and clinical determination of low risk (child protection team/social work assessment). Infants at high risk had significant intracranial injury, retinal hemorrhages, other skeletal injuries and clinical determination of high risk. There were 52 low-risk infants (mean: 4.7 months, range: 0.4-12 months) and 21 high-risk infants (mean: 4.2 months, range: 0.8-9.1 months). Two blinded radiologists independently evaluated the skeletal survey radiographs of the knees/lower legs for the presence of at least one growth recovery line.

RESULTS

When growth recovery lines are scored as probably present or definitely present, their prevalence in the low-risk group was 38% (standard deviation [SD] = 8%; reader 1 = 17/52, reader 2 = 23/52) vs. 71% (SD = 7%; reader 1 = 16/21, reader 2 = 14/21) in the high-risk group (P < 0.001; odds ratio 4.0, 95% CI: 1.7-9.5).

CONCLUSION

Growth recovery lines are encountered at a significantly higher rate in infants at high risk vs. low risk for abuse. This suggests that abused infants are prone to a temporary disturbance in endochondral ossification as a result of episodic physiological stresses.