Under the California Labor Code, there are two types of injuries that a California worker can suffer on-the-job or during their course and scope of employment.
The first type is there is a “specific" on-the-job injury. This is the most common type of work comp injury when people think of a work comp injury. For example, if you lift something heavy and injure your back, or if you are assaulted during work, or if you are involved in a car accident while making a work related delivery, then these are all considered a “specific” on-the-job injury that result directly from a specific incident that can be identified. There is no question of the causation of the injury.
The second type is called a “cumulative” or “repetitive” on-th-job injury. These types of injuries are injuries that happen over a period time; it is usually not due to one specific accident like the other type mentioned above. For example, you use your hands repetitively and you develop carpel tunnel syndrome, of if you are exposed to constant loud noise and you develop hearing problems, or you do a lot of walking or climbing at work and you develop knee pain or knee joint problems. Remember, even if you cannot point to a single incident as the specific cause of your injury or injuries, cumulative or repetitive injuries are still legitimate for claiming workers’ compensation benefits in the state of California under the California Labor Code.
Now, due to the fact that cumulative or repetitive use injuries develop over a period of time, there may be some contribution to these injuries by non-work related activities. This brings up the point of what is called "apportionment of injury." Some use of your hands at home might contribute to a work-related cumulative carpel tunnel syndrome for example. Also, it is possible some exposure to loud noise off the job may contribute to a cumulative on-the-job hearing loss. If you use your body in other activities when you are off work, like running or jogging, this recreational activity may contribute to a cumulative work knee injury or knee joint pain. This is still okay for your work comp claim you filed as long as some portion of your cumulative trauma injury was caused by your work activity. If this is true, then you still have a legitimate claim under the California Labor Code (California law). In addition to physical injuries, psychological injuries can also happen either as a “specific injury” or a “cumulative trauma” and are legitimate for claiming workers’ compensation; these types of claims are called "psych claims" but they are highly scrutinized, and you really need to speak with an experienced California workers compensation lawyer if you feel any of the above may be connected with your specific work injury. Remember, as with any bodily injury claim, work related or not work related, time is of the essence, and you should get medical care as soon as possible to make sure you are protecting yourself medically!