The thumb has reduced range of motion, affecting its ability to bend or move fully.
The key measurement is the distance between your thumb pad and your fingers when you attempt full opposition. Medical records showing a range-of-motion examination that documents this gap in inches or centimeters directly address the rating criteria. A VA compensation and pension exam or a private physician's exam that records this specific measurement is the most direct form of evidence.
Imaging such as X-rays can help show structural causes of limited motion, though the gap measurement itself drives the rating. If the limitation affects your ability to grip, pinch, or handle objects, treatment records and clinical notes that describe those functional losses support the documented measurement.
Statements from you or people who know you — describing difficulty with tasks like buttoning clothing, writing, or using tools — can help show how the restricted motion affects your daily life and work. These statements are most useful when they connect directly to the gap in thumb opposition that your medical records document.
Conditions that are often caused or made worse by this one. If you have any of these, they may be claimable as secondary service connection.
