Why does rotator cuff tear cause pain when lifting the arm?

The rotator cuff helps guide the upper arm bone as the shoulder moves. When a tendon is torn or irritated, lifting the arm increases its load and may reduce smooth control of the joint. The tendon can also become sensitive as nearby tissues are compressed during part of the movement. Pain may appear in a particular arc, especially when reaching overhead or away from the body, and weakness can make the movement feel harder. Shoulder pain with elevation has other possible causes, so the pattern needs an examination.

Reduce repeated overhead work and heavy lifting while the shoulder is painful, but avoid keeping it completely still for long periods. Use the arm below the painful range for light tasks and move gently within comfort. A clinician or physiotherapist can assess strength, range and control, then build a staged programme. Depending on the findings, care may include pain relief, targeted rehabilitation or discussion of other treatments. Note whether pain began after a specific event and which part of the lift is most difficult.

Seek prompt assessment after a fall, sudden pull or lifting injury if you cannot raise the arm or weakness is immediate. Get urgent help for a visibly deformed shoulder, new numbness, a cold or pale hand, or severe pain with fever. Arrange review when lifting pain persists, limits dressing or work, or is accompanied by night pain.

Ask what part of the movement is provoking pain, whether strength testing suggests a tendon tear, and whether imaging would change treatment. Discuss safe reaching limits, suitable exercises, and how to progress lifting without repeatedly irritating the shoulder.