School children and backpacks go together. “Wearing backpacks improperly or ones that are too heavy put children at increased risk for spinal injury,” American Physical Therapy Association (APTA) member Mary Ann Wilmarth, director of the transitional doctor of physical therapy degree at Northeastern University in Boston, explained. “If we don’t correct the backpack issues that are causing children back pain, the issue will become magnified in years.”

Some backpack safety tips:

• Wear both straps in order to better distribute the weight and to promote a well-aligned symmetrical posture. Using a single strap forces one side of the body to bear all the weight.

• Be careful when putting on and removing backpacks. Keep the trunk of the body stable and avoid excessive twisting.

• The backpack should be positioned over the strongest mid-back muscles. It should rest evenly in the middle of the back and should not extend below the low back. The shoulder straps should be adjusted to allow a child to easily put on and take off the backpack and permit free movement of the arms. However, the straps should not be too loose.

• Limit the backpack load to 10-15 per cent of the child’s bodyweight. Only carry items that are required for that day. The heaviest items should be placed closest to the back in order to protect against posture problems and muscle strain.

Warning signs that a backpack is too heavy include a change in posture when wearing the pack; struggling when putting on or removing the pack; pain when wearing the pack; tingling or numbness in arms; red marks on shoulders.

When choosing a backpack, look for features that enhance safety and comfort:

• A padded back to reduce pressure on the back, shoulders and underarm regions.

• Hip and chest belts to transfer some of the weight from the back and shoulders to the hips and torso.

• Multiple compartments to help distribute weight in the pack and provide easy access to contents.