While the VA uses complicated medical terms and specific diagnostic codes you are not required to use the terms or codes in your claim. You should focus on any condition that was caused or aggravated because of an event or exposure in service. Your representative will be able to assist with the proper way to document your condition on the VA forms.
Additionally, after your are service connected, you may claim Secondary conditions which are other conditions that are most likely a result of your service connected condition. An example of a secondary condition would be a veteran who has a bad right knee from excessive running and carrying heavy loads in service. Because of a limp in the right knee, the veteran develops pain and a limit of the range of motion in the right hip as he compensates for the knee pain. In this hypothetical case, the right hip would be secondarily service connected to the right knee.
Some veterans who were stationed in specific areas of the world during a specific time period may be eligible for service connection to certain conditions without showing an event or exposure in service, although the VA may still request service and treatment records.
Vietnam veterans with heart conditions, diabetes or certain cancers may qualify for immediate service connection with a current diagnosis, because of a presumed exposure to Agent Orange. The veteran will still need to show that he/she stepped foot into Vietnam or was a “brown water” veteran which means that he/she navigated the inland waterways.
Veterans stationed in Thailand during the Vietnam era may also qualify for presumptive conditions if they meet certain criteria.
Gulf war veterans may also qualify for service connection for presumptive conditions such as Chronic Fatigue Syndrome, Fibromyalgia and others.
Other categories of presumptive eligible veterans include former Prisoners of War and veterans who were exposed to ionizing radiation, also known as Atomic Veterans. Contact your VA representative for more information or reference the VA website for presumptive conditions.