Implementation of new working methods in the floor-laying trade: Long-term effects on knee load and knee complaints

This study compared floor laying using new working methods involving standing up, to the traditional methods involving working on one's knees.

The study group, 216 subjects, completed a training class in the use of the new floor-laying methods, and received free tools and advice in their use. The control group, 454 subjects, did not get any training, but were free to use the new methods if they wished. In a 2-year-follow-up the effects were evaluated by questionnaires and by in-depth interviews of industry representatives. Regression analysis was used to control for age, body mass index (BMI), and self-reported stress. The quality of the work and time used to perform it comparing the new methods and the traditional methods was evaluated.

Two years after the training, 38% of participants in the study group used the new working methods weekly or daily compared with 16% of the control group. The risk was at least double for serious knee complaints among floor layers who had not used the new working methods. There were no increased risks for other musculoskeletal complaints involving any other part of the body associated with the use of the new method.

Within a 2-year time period, the introduction of new working methods in the floor-laying trade has succeeded. More efforts are needed to sustain the use of the methods among those workers who have been trained and to introduce the methods to those workers who do not yet use them.