BACKGROUND INFORMATION Most school-aged children carry backpacks regularly, often loaded with heavy books and other items that can add up to a substantial amount of weight. In fact, studies indicate that backpacks are often loaded with 10-22 per cent of a child’s body weight 1, 2! When worn up to 60 minutes a day, it is understandable that growing concern exists regarding the relationship between carrying heavy backpacks and back pain in children. Roughly 40 per cent of children report back pain and many of them attribute this pain to backpack use3. Further, a recent study4 revealed that contact pressure under backpack straps can be substantial, and result in pain in children. To date, there has not been a radiographic study investigating the response of the pediatric spine to backpack loads in a standing position. This study utilized a new standing magnetic resonance imaging (MRI) technique to provide detailed analysis of intervertebral disc compression and spinal curvature changes in response to increasing backpack loads in children, without the associated risks of radiation that accompany other imaging methods. PERTINENT RESULTS Increasing backpack loads of four, eight and 12 kilogram significantly compressed lumbar discs in a linear fashion in the sagittal plane (P < 0.05). • The L5-S1 disc was more “compressible” – displaying compression of up to two times that of the T12-L1 disc. • Subjects reported significantly higher pain (up to ~50 per cent) with higher backpack loads (P < 0.001). This relationship was linear (r2=0.711), but this may have been a result of subjects being aware that the load was increasing. • No statistically significant relationship was identified between spinal load and lordosis (although a trend was noticed). • Although the correlation coefficient was small (r2=0.124), increasing backpack loads increased coronal spinal asymmetry – this was most noticeable with the eight-kilogram load (9.18°±2.25°). With the 12-kilogram load, subjects were observed adjusting their posture more frequently, which may have altered this measurement (and measurement of lordosis above). • Four of the eight subjects displayed Cobb angles > 10° during loading. CONCLUSIONS AND PRACTICAL APPLICATION As spine care experts, we are well positioned to discuss this issue with our school-aged patients and their parents. In addition to dealing with related musculoskeletal pain when it arises, practitioners should educate patients about minimizing backpack load, maintaining proper posture, backpack use (always two straps!), and employing tissue sparing techniques. Recently, profession-wide initiatives have been aimed at educating the public on this issue. The findings of this study could now be included in this information and help us stay on the cutting edge of emerging scientific literature on this topic.