Pediatric Scapholunate Distance

Normal Ranges of SLD in Children 6 to 14 Years Old

Author(s): Kaawach W, Ecklund K, Canzio JD, Zurakowski D, Waters P

Source: J Pediatr Orthop

Summary:

Although scapholunate injury is uncommon in children, this study provides normative values according to the age of the child.

In adults, > 2mm of scapholunate distance (SLD) commonly suggests pathology. In contrast, SLD in children is naturally larger than 2 mm consequential to ossification of the carpal bones. The lunate is not present on x-ray until 4 years of age and the scaphoid until 5 years. Girls reach adult values of 2 mm by age 11 and boys by age 12.  The scaphoid also ossifies in an irregular fashion, which further complicates measurements. Linear regression revealed equations to calculate SLD for each sex.

Boys: SLD = (-0.7 x chronological age (years)) + 13.6
Girls: SLD = (-0.6 x chronological age (years)) + 10.4