According to a new study in the journal Scoliosis, asking parents when they last bought new shoes for the child and what size those shoes were can help doctors know when kids are most vulnerable for scoliosis and to provide treatment if needed.
Scoliosis is a curving of the spine. The spine curves away from the middle or sideways. Curves generally worsen during growth spurts.
Of the three types of scoliosis -- congenital (present at birth), neuromuscular (caused by problems such as poor muscle control or muscle weakness), and idiopathic scoliosis (unknown cause) -- adolescent idiopathic scoliosis (AIS) is the most common.
About 4.5% of children develop AIS around puberty when their spinal column lengthens due to sudden growth spurts. Knowing the timing of the pubertal growth spurt of the spine is important for the prognosis and therapy of adolescent idiopathic scoliosis (AIS).
Professor Albert G Veldhuizen, University of Grogingen, Netherlands, and colleagues analyzed data concerning shoe sizes of girls (242) and boys (104) acquired from two large shoe shops from 1991 to 2008 for the age of the "peak increase" in shoe size, as well as the age of cessation of foot growth based on shoe size.
Data was collected each time a client visited the shoe shop. Each client's bare left and right foot were measured individually while standing full weight bearing. The shoe size was measured to the nearest half-size, and an average was taken for both feet.
The individual series of ages of the clients ranged from 10 months to 17.1 years in girls, and 10 months to 17.2 years in boys.
The researchers found the average peak increase in shoe size occurred at 10.4 years (SD 1.1) in girls and 11.5 years (SD 1.5) in boys. This was on average 1.3 years earlier than the average peak growth velocity of sitting height in girls, and 2.5 years earlier in boys.
The shoe size did not increase any further for at least 1 year after the age of 12.0 (SD 0.8) in girls, and 13.7 years (SD 1.0) in boys.
The researchers note “These results suggest that the longitudinal course in shoe size and the timing of the peak increase in shoe size can be helpful as a first indication for the timing of the pubertal growth spurt of sitting height.”
As patients and parents can recall when they bought new shoes, and what the size was, shoe size can be used as an alternative data source to actual foot length.
The researchers write “When the increase in shoe size is approximately 2.5 sizes per year (in both girls and boys), the physician knows that on average the peak growth velocity of sitting height will occur 1.3 or 2.5 years later in girls and boys respectively.”
While the course of the shoe size of children can be useful as a first indicator for the timing of the pubertal growth spurt of sitting height, this claim needs verification by direct comparison of individual shoe size and sitting height data.
The value of shoe size for prediction of the timing of the pubertal growth spurt; Scoliosis 2011, 6:1doi:10.1186/1748-7161-6-1