How common is muscle weakness in rotator cuff tear?

The rotator cuff is a group of tendons and muscles that helps centre and move the shoulder joint. A tear can reduce the force transmitted through one or more of these muscles. Pain can add a second effect: you may stop the movement early because it hurts, making the arm seem weaker than it is.

Weakness may be most noticeable when reaching overhead, fastening clothing, placing an object on a shelf or lowering the arm. The location and size of a tear, the timing of the injury and the condition of the shoulder muscles all influence the pattern. A physical examination can compare movement and strength on both sides; imaging may be considered when it would change care.

Book an assessment if weakness follows a fall, lifting injury, sudden pull or persistent shoulder pain. Until reviewed, keep the shoulder moving gently within a comfortable range, avoid repeated overhead loading and do not test strength with heavy weights. A clinician or physiotherapist can tailor exercises and explain whether rest, rehabilitation or another treatment approach fits the findings.

Seek prompt care after an injury if you cannot lift the arm, the shoulder looks deformed, swelling is substantial, or pain is severe. Urgent assessment is also appropriate for weakness with chest pressure, breathlessness, sweating or pain spreading to the jaw or arm. New numbness or a cold, pale hand needs prompt medical attention.

Ask: Does my examination suggest tendon pain, a tear, or weakness from another source? Which shoulder movements should I limit? Would physiotherapy be suitable now? When would imaging help? What changes in strength, sensation or hand colour should make me seek urgent care?