As the van pulled into the loading dock, Dennis knew he was facing a long, tough day. The boxes of samples weighed 57 pounds each, and they had to be stacked on pallets to be distributed to the manufacturer's representatives later in the week. Even though he had a hand truck available, he still had to physically pick up each carton, stack it on the dolly, push the loaded dolly to the warehouse and unload the cartons from the dolly to a pallet on the floor. It wouldn't have been as difficult if his helper was there, but Jim had called in sick that morning, and no one else was free at the moment to help him. Because there were so many containers, Dennis decided that the only way he could finish in time was to stack four or five boxes at a time and move them quickly.

He started at 7:30 a.m. and finished the job just before lunch. He noticed by late morning that his back was sore and getting worse with each load. Although he did not work on the dock after lunch, his back pain increased. By the middle of the afternoon the pain was intolerable. Dennis was used to handling heavy material and prided himself on being in excellent physical condition, but the loads had been too heavy.

Dennis had some alternatives that probably would have protected him: he could have waited for a helper; used a better mechanical device such as a forklift; or loaded only one or two cartons at a time. Then the weight would have been tolerable.

The injury that Dennis experienced is a form of overexertion injury, but is compounded by the weight of the material. The spine can withstand only so much weight before it rebels. An overload injury can result in a ruptured or herniated disc, which may require surgery.

The National Institute of Health and Safety estimates that most men in the United States can lift 36 pounds on a repetitive basis, and women can lift 28 pounds repetitively. That doesn't sound like much, but if you are having to pick up a load every minute - or even every five minutes - the spine is having to adjust to those loads very quickly. The body mechanics positions used are also critical in avoiding overload injuries

Although Dennis was in good physical condition, the loads were excessive. Knowing your strength is important, but listening to your back is equally important. Dennis forgot that. Poor judgment may put Dennis in the hospital. Surgery and three to six months of recuperation are possible. Overloading your back is not worth the price.