Design and validation of a novel ergonomic backpack.

Background: BP are the most common means for carrying items and are used by a large population but transporting heavy loads (over extended periods of time) can lead to a variety of health-related problems. An ergonomic backpack (EBP) was designed as a potential solution to reduce the incidence of injuries associated with heavy backpack weight.

Objective: The objective of this study was to design a novel ergonomic offloading backpack that reduced loads on the shoulder and spine compared to a traditional modern day backpack (BP).

Methods: Strap tension and shoulder loads were measured in a common two strap style commuter BP and the EBP during quiet (vertical) stance conditions for five weight increments (0 kg to 11 kg) to confirm the offloading capabilities of the EBP. Portable luggage scales were attached directly to the shoulder straps and configured to measure strap tension. Load sensors placed underneath the shoulder straps provided an estimate of the total force acting on the shoulders and transferred to the spine.

Results: The EBP had a large effect size and significant reduction ( < 0.05) in shoulder loads compared to a traditional BP for all bag weight conditions. Similarly, the EBP had a large effect size in reducing strap tension compared to the traditional modern day two strap BP.

Conclusion: A newly designed EBP was effective at transferring a significantly large portion of the shoulder and spine loads to the pelvic region.