title: An ergonomic study of chronic musculoskeletal pain in schoolchildren.
abstract: OBJECTIVE
  Schoolchildren developing chronic musculoskeletal pain from carrying heavy backpacks (hereafter referred to as "pain") is a worldwide issue. The present study of two cohorts, consisting of 248 Indian and 103 American schoolchildren aged 9.0 to 20.6 years, using a semi-objective pain criteria, sought to answer the questions: Can pain be correlated with Body Mass Index (BMI), Weight Carried, Strength, Mood or Body Fat? What are the similarities and differences between the Indian and American schoolchildren in the above context?
  
  
  METHODS
  After obtaining parental consent, the schoolchildren completed a questionnaire. Then, they were weighed with and without carry-on items and their height as recorded. Isometric arm and shoulder strengths were measured using the Jackson Strength Tester. Using a Skinfold Caliper, skinfold thicknesses at the right triceps and calf was measured. Using the Borg Pain Scale the students assessed the pain experienced from their own backpacks, rated the acute pain experienced while carrying a standard 10 kg. or 7 kg. backpack.
  
  
  RESULTS
  Half the schoolchildren reported pain located primarily in the shoulders and back (where most students carry their backpacks). Pain did not correlate with study variables (p > 0.05), and the student moods were mostly happy or neutral. Americans are five times as stressed or sad than the Indians, and the average weight carried decreased as the grade increased. The mean of the age, height, arm and shoulder strengths, and BMI for the 5th to 8th grade schoolchildren (younger groups) and the 9th to 12th grade schoolchildren (older groups), in India, was lower than their American counterparts (p < 0.05). In contrast, the weight carried to school by the Indian children was higher (p < 0.05). The mean pain level perceived by both the younger and older groups in both countries, was not statistically different (p > 0.05).
  
  
  CONCLUSIONS
  Musculoskeletal pain in schoolchildren due to carrying heavy backpacks is a significant problem. There are some similarities, but a number of differences between the Indian and American schoolchildren. Implementing the Pain Prevention Screening is expected to minimize pain, if not lead to a pain-free child.
authors.affiliation: Clear Lake High School, Houston, Texas, USA. shrie@msn.com
authors.forename: S R
authors.initials: SR
authors.lastname: Iyer
mesh_terms: D000293:Adolescent; D000328:Adult; D000339:Affect; D001827:Body Height / Q000208:ethnology; D015992:Body Mass Index; D002648:Child; D015331:Cohort Studies; D016552:Ergometry / Q000379:methods; D006801:Humans; D007194:India / Q000453:epidemiology; D009140:Musculoskeletal Diseases / Q000209:etiology*; D010146:Pain / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D014481:United States / Q000453:epidemiology; D016474:Weight-Bearing / Q000502:physiology