Risk assessment of biomechanical overload of the cervical spine and upper limbs in a population of professional drivers

Introduction
In literature disorders of the cervical and lumbar spine, shoulder, hands and wrists in rally and off-road professional drivers, forklift truck drivers, delivery drivers, truck drivers, drivers of emergency vehicles, bus and taxi drivers were reported. The aim of the study was to evaluate the muscular effort in the cervical spine, the shoulder girdle and upper limbs in a population of professional drivers while running tests for tires producers.

Methods

The study was conducted using surface electromyography (sEMG) during the tires tests. The difference in muscle work of the cervical spine and upper limbs was evaluated in three different conditions. The results are expressed as a percentage of MVC (maximum voluntary contraction). 

Results

The tests using less comfortable car seats (the production models) show very significant lower peak values of force comparing when the helmet was used and when it was not. There was a less significant lowering of peak values shown when comparing use of a large helmet with the use of a smaller helmet. These results are not as significant for tests conducted on two other cars with more comfortable seats (custom built seats) to limit arm, trunk and neck jerking and therefore peaks of force, independent of the type of helmet worn.

Discussion
In cars with less comfortable seats, high force levels in the upper limbs were identified due to the need to keep the rider in place during the execution of curves or sharp turns. It would be useful to have more models of contained systems to test with workers and to repeat the EMG tests in order to identify the best solution.