The impact of the forces exerted by backpacks on load distribution, back pain, and gait is considerable. Backpack use is associated with back pain, intervertebral disc compression, neck pain, altered posture, altered walking mechanics, and plantar foot pressure. With persistent eccentric loading the process of wear, tear, and degeneration proceeds and surgery may be needed.
A new study has assessed the impact of forces exerted by specific backpack weights on a model of the spine. This information will be useful for understanding the load that the spine experiences as an applied weight increase, and for recommended maximum weights to be put in place.
The new research was undertaken by Dr. Kenneth K. Hansraj, who is a spinal and orthopedic surgeon specializing in cervical, thoracic and lumbar procedures, bloodless spine surgery, minimally invasive spine surgery, laminectomies and spinal fusions.
Dr. Hansraj has written to Digital Journal with the results of the new study. The study involved using a model of a human spine, which was subjected to loads induced by carrying a backpack of different weights. The researchers modelled two alternate scenarios.
Scenario one considered carrying a regular backpack with incrementally placed weights using both shoulder straps with the spine in a neutral position. The second scenario considered a regular backpack with incrementally placed weights using both shoulder straps with the spine tilted forward by 20 degrees.
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The study results showed that with each of the weights examined, the axial compression force for a neutral spine was 7.2-fold the backpack weight. In addition, for the 20 degrees forward flexion condition, the axial compression force was 11.6-fold the backpack weight.
The research findings could assist with an understanding of the forces experienced by the spine due to objects in a backpack. Such an insight should help spinal surgeons to better understand the tremendous importance of sagittal plane alignment in planning their surgical reconstructions.
The research also helps with prevention strategies. This includes understanding that one book is equivalent to seven books to the spine; getting students to think about how backpacks are packed; and considering alternate technology like using digital books.
The research has been published in the journal Surgery Technology International. The research paper is titled “Backpack Forces on the Spine.”
