Perhaps the most common symptom of rotator cuff injury is shoulder pain, on the front and side of the joint. This can occur within a short period after the injury or gradually over time. The pain may be most acute at night while trying to sleep, especially if weight is placed on the shoulder.
Another possible symptom is the limited range of motion in the shoulder. There can be difficulty moving the arm away from the body, even with assistance from another person. If the tendon is torn, it may be impossible to lift the shoulder at all. The person may become incapable of performing normal functions, such as combing hair.
Weakness can occur with a rotator cuff injury, especially when attempting to raise the arm. If the injury is acute, such as the result of a sudden sports injury, the weakness can occur immediately. With a chronic rotator cuff injury, the weakness is more likely to occur over time.
The injured person may hear unusual sounds, such as cracking or popping, emanating from the joint when attempting to move the shoulder. This is a condition known as crepitus, which is a wearing of the cartilage in the shoulder joint.
Because of the shoulder pain that can be caused by a rotator cuff injury, the injured person may refrain from using the shoulder muscles, which can cause the muscles to atrophy due to lack of use. If this occurs, the resulting symptom would be a thinning of the shoulder muscles.