MONDAY, Aug. 27, 2007 (HealthDay News) -- Backpacks help kids carry schoolbooks and supplies, but they can also be harmful when overloaded and/or improperly fitted, warns the American Physical Therapy Association.
"Wearing backpacks improperly or ones that are too heavy put children at increased frisk for musculoskeletal injuries," Mary Ann Wilmarth, assistant dean and director of the transitional doctors of physical therapy degree at Northeastern University in Boston, said in a prepared statement. She's conducted a number of studies on school backpacks.
Injuries occur when children use faulty postures -- such as arching the back, bending forward, twisting, or leaning to one side -- when they're trying to manage a heavily loaded backpack. These faulty postures can cause improper spinal alignment, which hampers the functioning of spinal discs that provide shock absorption, Wilmarth explained.
Overloaded backpacks also place an extra burden on muscles and soft tissues, causing fatigue and strain that increases the risk of neck, shoulder and back injuries.
Wilmarth offered some backpack safety tips:
- Use both straps in order to better distribute the weight of the backpack and to promote a well-aligned, symmetrical posture. Using one strap means that one side of the body has to bear most of the weight of the backpack.
- Be careful when putting on and removing backpacks. Keep the trunk of the body stable and avoid excessive twisting.
- The backpack should be positioned evenly in the middle of the back, near the wearer's center of gravity. The backpack should not extend below the lower back. Adjust the shoulder straps so that the child is able to put on and remove the backpack without difficulty. While the straps should not be too loose, they should be adjusted to permit free movement of the arms.
- Keep the load at 10 percent to 15 percent or less of the child's bodyweight. Children should carry only items they require for the day. The heaviest items in the backpack should be positioned closest to the back.
- Encourage children to be active, in order to promote better muscle strength and flexibility, which makes it easier to carry a backpack.
The American Academy of Orthopaedic Surgeons has more about backpack safety.