First, if you have suffered an injury at work and not yet reported it to your employer, you should do so immediately! There are strict deadlines for actually reporting an injury once you are aware the injury is related to your work activities. Failure to report the injury might be a bar from any possible recovery.

Notice of a work- related injury should be given to a supervisor, human resources director, or someone else in a position of authority with the employer. This person should give you a DWC-1 to fill out. The
DWC-1 outlines the nature of your work injury and how it relates to your work. You or your employer should then recommend you to a Redding Worker's Compensation doctor to document the injury and obtain treatment.

However, some injuries are difficult to determine if they are work related. The legal test is whether the injury arose out of employment through the course of the employment.

For the full article of determining whether your injury is work related.