The Back-Scratch Test: What This Simple Reach Says About Shoulder Health

The test checks how far each arm can reach in two directions at once. One hand goes up over the shoulder, the other goes up from below, and you look at the gap between the fingers.

It is a practical check of shoulder reach, the everyday range you use to fasten a bra, tuck in a shirt or wash your hair. A small gap on one side is common and does not automatically mean a problem.

Reach depends on the joint, the muscles around it, and the upper back. Many clinicians suggest the muscles that move the shoulder blade matter as much as the joint itself.

• Strength, mobility, body composition and posture are all associated with shoulder problems in adults 60 and older, and these are targets you can work on. The link with forward head posture is indirect and limited [R28].
• A 12-week Thai Yoga program improved shoulder reach, measured with a back-scratch test, in sedentary adults over 60 compared with a control group [R11].
• There is no agreed pass mark for the test in the research here; ask your clinician how to read your result.

1. Stand or sit tall. Relax your shoulders, and warm up with a few slow circles first.
2. Test one side at a time. Note how close the fingertips get, and whether any pain appears.
3. Repeat on the other side, and compare. Do not force the reach.
4. Seated option: sit in a firm chair and do gentle reaches with a towel held between your hands, sliding the hands closer over several weeks.
5. Retest once a month, and track the result in a simple note.
6. Stop if you feel sharp pain, a pinch or numbness.