A matched case-control study of nonoccupational risk factors for herniated lumbar disc

• Main Author: Mundt, Diane J
• Language: ENG
• Published: ScholarWorks@UMass Amherst 1990
• Subjects: Public health
• Online Access: https://scholarworks.umass.edu/dissertations/AAI9022726

Lumbar disc disease, specifically herniated lumbar disc, is responsible for considerable activity limitation, disability and impairment. Biomechanical and experimental studies have shown various compression loads and torsional forces to be related to herniated disc; however, epidemiologic studies of risk factors for herniated disc are limited, focusing primarily on occupational activities. This research examines the role of non-occupational activities as potential risk factors for herniated disc, as one component of a larger multi-center matched case-control study of risk factors for herniated disc. New cases of herniated disc were identified and matched to controls by age, sex and source of access. Study participants were interviewed to ascertain data pertaining to risk factors. Data were analyzed using conditional multiple logistic regression analysis to obtain odds ratios and 95% confidence intervals for associations between non-occupational activities and herniated disc among 276 case-control pairs. The major study findings indicated that lifting 25 or more pounds off the job, and the various aspects of the lift, such as position while lifting (knees straight, back bent), starting the lift with arms extended more than half the time, twisting while lifting, and lifting from and to waist level were associated with herniated disc, each compared to no lifting; the strength of the association was greater among confirmed cases of herniated disc. Repeated bending compared to no bending was also shown to be associated with herniated disc, particularly among confirmed cases. Associations were also evident for lifting 10-24 and 25 or more pound children with knees straight and back bent. Sports activities in general were negatively associated with herniated disc; playing golf or racquet sports frequently were strongly associated in the negative direction, compared to not participating in these sports. Bowling showed a slight positive association with herniated disc. No associations were found for pregnancy history, use of free weights or weight lifting equipment. Results are consistent with findings on risks of occupational activities, and with biomechanical studies.