Lower extremity knee disorders, like other cumulative disorders of the body, build up over time through cumulative exposures. 2006 data from the U.S. Bureau of Labor Statistics reveal that cumulative knee disorders account for 65% of lower extremity musculoskeletal disorders and 5% of total body musculoskeletal disorders.
The objective of the literature review was to find papers on work-related musculoskeletal disorders (WMSDs) common to the knee region. From these, symptoms of the disorders, affected industries, and potential risk factors were assessed.
A review of the literature divulges that knee disorders primarily consist of bursitis, meniscal lesions or tears, and osteoarthritis. Though kneeling and squatting are considered to be two of the primary risk factors correlated to these knee disorders, 12 other risk factors should also be contemplated. These 14 contributing risk factors include both occupational (extrinsic) and personal (intrinsic) variables that affect the labor industries. Example industries include mining, construction, manufacturing, and custodial services where knee bending postural activities exist as a commonality.
The understanding of the types of knee disorders, the affected occupations, and the job related risk factors will allow ergonomic practitioners and researchers to create and adjust work environments for the detection and lessening of knee work-related musculoskeletal risk. Further studies need to be conducted to (1) justify the presence of risk from certain risk factors and (2) enhance the understanding of risk factor dose-response levels and their temporal development.