Study Design

Strength testing of lumbar extensors of shipyard workers without back injury claims was accomplished to compare isolated lumbar strength with the severity of their workplace back injury during a 2-year period.

Objectives

To determine if strength is a predictor of workplace injury and if there is a relationship between the physical demands of the job and strength.

Summary of Background Data

The role of preplacement strength testing has not been clarified as a potential means for predicting workplace injury.

It has not been clarified whether work activity affects the strength of the worker.

Methods

One hundred fifty-two shipyard workers were strength tested for isometric lumbar extensor strength.

They had been classified as to the Physical Demand Characteristics.

All workers at this industry were like-wise classified.

Those workers who were tested were followed for 2 years to evaluate for claims of back injury.

Results

There was a higher incidence of low back injuries in the heavy and very heavy classification.

There was, however, no difference in strength among those workers classified in medium heavy, and very heavy work.

Nine percent of those workers tested had back pains during the following 2 years.

All but two had higher-tahn-average strength

Conclusions.

There is no evidence that preplacement back strength testing would predict workplace claims of injury.