Any parent who has ever lifted his or her child’s school backpack knows that it routinely violates the Zero Tolerance policy for weapons in school. Hitting someone with that 20-30 pound sack of textbooks could do some serious damage. That’s if you could lift it.

The question an Easton reader posed to me was this: Can a super heavy backpack injure a kid’s back? I took that inquiry to Dr. Mark Walter, a chiropractor with VSAS Orthopaedics in Salisbury Township.

Walter said in 14 years of practice, he’s never treated a child who had permanent injuries from a backpack. But that might be because parents seek solutions before the pain can do long-term damage. 

“The utilization of a backpack not fitted or too heavy for young children would cause more acute immediate symptoms of back, shoulder, neck and possibly hip pain,” according to Walter.

In a 2004 study conducted by researchers with the University of California at Riverside, 64 percent of the approximately 3,500 school children surveyed reported pain from their heavy backpacks and 21 percent of those kids said the pain lasted more than six months.

“You don’t want a child to be carrying more than 10 percent of their body weight,” Walter said.

Unfortunately, that ship has sailed. It’s not unusual for a 70- or 80- pound kid to be carrying a 25-pound pack.

“But the problem isn’t just the weight but also how children carry the packs,” Walter said. “They don’t use the backpack appropriately. They sling it over one shoulder. You want to make sure it’s over both shoulders.”

(By the way, that’s the same for women with heavy purses. Instead of letting the bag hang off one shoulder, they should sling it so the strap goes across the body, distributing the weight more evenly.)