If you have or are at risk for lymphedema, tracking changes in your arm size is an important part of managing your care. Water displacement is a simple, cost-effective way to measure arm volume accurately at home.
What You Need:
- A large, clear container that comfortably fits your arm
- Running water
- A permanent marker
Step-by-Step Instructions:
- Prep the Container: Draw a horizontal line on the outside of the container, about 10–15 cm from the top. Fill the container with water exactly up to this line.
- Choose a Reference Point: Pick a permanent landmark on your upper arm (such as a distinct freckle, mole, or scar). Note: Always use this exact same spot for future measurements to keep results consistent.
- Submerge Your Arm: Slowly lower your arm into the water until the water line reaches your chosen landmark.
- Mark the New Water Level: Keep your arm still and draw a second horizontal line on the outside of the container at the new, higher water level.
- Calculate Volume: The volume of water between your original baseline line and the new line represents your arm volume.
When to Measure
- Before Surgery: Establish a baseline measurement so you know your arm’s standard size.
- After Treatments: Track changes following medical procedures, therapy, or interventions.
How to Interpret Your Results
- Water rises higher than previous tests: Your arm volume has increased (potential swelling or fluid buildup).
- Water level is lower than previous tests: Your arm volume has decreased (swelling is reducing).
Important Note: Overall body weight gain or loss can also affect your arm volume. Keep your general weight in mind when reviewing your measurements.