Claims that shoulder pain is a sign of injury are plausible if there has been an impact event or similar. Gradually emerging pain however can have many potential causes, some of which are addressed by ergonomics standards. But is breach material? This would depend on context and degree of breach.
Evidence from:
H Miranda et al. Occupational and Environmental Medicine. Aug (2001) Vol.58 #8 p 528.
It is tempting to assume that breach of duty must imply a material contribution. However, standards developed for regulation may not meet the standards required by the common law.
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