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Low back pain (LBP) has been described as one of the most prevalent and significant musculoskeletal problems, with upwards of 85% of the population experiencing LBP at some point in their life. Of those experiencing LBP, up to 85% will not receive a definitive diagnoses as to the cause of the pain. Although a number of known injury sites exist within the low back, because of the ongoing occurrence of LBP, other injury mechanisms must still exist. Complicating pain is the fact that there are several pain pathways as well as there are no objective measures of pain. Recently, it has been shown that exercise induced muscle inflammation, which causes pain, can be analyzed using magnetic resonance imaging (MRI). In addition, magnetic resonance spectroscopy (MRS) has been shown to be able to detect changes in the chemicals in the brain, which are known to respond to painful stimuli. Given these two factors, the goal of this study was to identify whether inflammation in the low back musculature (measured using MRI) could be linked with metabolite changes in the brain known to respond to pain (measured with MRS). Ten healthy subjects (5 males and 5 females) underwent baseline lumbar and brain scans and then completed a lifting and lowering designed to produce inflammation in the erector spinae muscles. Subjects were asked to lift a 9.1 kg carton 8 times per minute until they could no longer do so. Following completion of the lifting task, subjects underwent another lumbar and brain scan. Twenty-four hours later a final lumbar and brain scan series was completed. Subjective ratings of perceived exertion and pain levels were also collected at baseline, immediately following the lifting task, and 24-hours after completing the task. T2 maps were used to analyze muscle inflammation. In an unexpected finding, T2 relaxation times actually decreased significantly following the completion of the lifting task. Glutamate and glutamine, pain markers, were not elevated based on the MRS analysis even though subjective pain ratings were moderate at completion of the task. Twenty-four hours following the lifting task T2 relaxation times were significantly elevated above baseline values, which correlated with subjective pain ratings, which remained elevated. However, no significant changes MRS pain markers were detected. Limitations included a small sample size, limited ability to identify the temporal nature of inflammation and pain, and the use of only healthy subjects. While a definitive link between muscle inflammation and brain response could not be proven, the study did provided some interesting insights for future work.

Millions of youth work on farms and routinely undertake physically demanding tasks. While a high percentage of youth report musculoskeletal pain, research has not been conducted on what interventions could reduce the risk of pain/injury. Therefore, the purpose of this study was to test several interventions for shovels (add-on handles) and wheelbarrows (additional wheels or adjustable handles) during common farm tasks. Based on the results, the add-on handles may not be completely effective in reducing risk of low back injuries during shoveling tasks. While add-on handles reduced sagittal trunk motion, there was a trade-off with increased twist motion compared to a regular handle scoop shovel. For the wheelbarrows, a large reduction in sagittal flexion and velocity was achieved using the wheelbarrow with three wheels or the adjustable handle. However, for both types of equipment, none of the interventions showed any significant change in the predicted low back disorder risk level.