Experiencing pain at the top of your shoulder when you lift your arm is a common musculoskeletal complaint. This discomfort, often felt during the arc of movement when reaching overhead, indicates an issue with the structures located beneath the bony roof of your shoulder. Understanding the source of this discomfort is the first step toward finding relief and restoring full movement.
Understanding the Shoulder’s Mechanics
The shoulder is a complex ball-and-socket joint that allows for an incredible range of motion, relying on a delicate balance of bones, tendons, and cushioning sacs. The pain you feel is often related to the interaction between the humerus (upper arm bone) and the acromion, which is the bony projection at the top of the shoulder blade. The space between these two structures, called the subacromial space, is quite narrow.
This tight area houses the rotator cuff tendons and a small, fluid-filled cushion known as the bursa. These soft tissues stabilize the shoulder and initiate movement. When you elevate your arm, they must slide smoothly beneath the acromion, but inflammation or structural changes can interfere with this precise movement.
The Most Common Causes of This Pain
Pain when lifting the arm is frequently linked to a reduction in the subacromial space, leading to soft tissue compression. The most common condition resulting from this is often referred to as shoulder impingement syndrome. This occurs when the rotator cuff tendons, particularly the supraspinatus, get pinched against the acromion as the arm moves upward.
Shoulder Impingement Syndrome
The pain from impingement often begins when the arm is lifted to about shoulder height and then worsens through the middle range of the lifting motion, known as the painful arc. This mechanical irritation can lead to rotator cuff tendinitis, which is inflammation of the tendon fibers. The pain is typically felt on the outer side and top of the shoulder and can sometimes radiate down the side of the arm.
Bursitis
Another frequent cause is bursitis, which involves inflammation of the bursa located directly above the rotator cuff tendons. The bursa normally functions as a cushion to reduce friction between the moving parts of the shoulder joint. When the bursa becomes inflamed, often due to repetitive motion or an underlying impingement, it swells and takes up more space, leading to increased pressure and pain when the arm is raised.
Acromioclavicular (AC) Joint Issues
For pain localized specifically at the very top of the shoulder, often right on the bony prominence, the issue may be related to the acromioclavicular (AC) joint. This joint connects the clavicle (collarbone) to the acromion and can become painful due to degeneration, injury, or arthritis. AC joint pain is usually very localized and tender to the touch, often worsening with movements that bring the arm across the body or involve high overhead reaching.
Immediate Steps for Relief at Home
For new or minor shoulder pain, the first step is to modify activities that aggravate the condition. You should temporarily avoid repetitive overhead movements, heavy lifting, or carrying heavy bags on the affected shoulder. This does not mean completely immobilizing the arm, as gentle, pain-free movement is necessary to prevent stiffness and a potential worsening of the condition.
Applying a cold pack to the painful area can help reduce inflammation. Use an ice pack wrapped in a towel for about 15 to 20 minutes several times a day. Over-the-counter non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, can also provide temporary pain relief by targeting inflammation, but should be taken as directed.
Awareness of your posture is also helpful, particularly while sitting or standing for long periods. Slouching causes the shoulder blade to move forward, which can further narrow the subacromial space and increase the chance of pinching the tendons. Try to sit upright with your shoulders gently back and your back supported to maintain a neutral spine position.
Seeing a Doctor and Treatment Options
If your shoulder pain is severe, follows a traumatic event, or does not begin to improve after two weeks of home care, a professional evaluation is appropriate. Seek immediate medical attention if you experience sudden, intense pain, have an inability to lift your arm at all, or notice numbness or tingling radiating down your arm. These signs may indicate a more significant injury, such as a full rotator cuff tear or a pinched nerve in the neck.
A doctor will perform a physical examination to test your range of motion and strength. They may order imaging like X-rays to check for bone spurs or arthritis, or an ultrasound or MRI to evaluate the bursa and rotator cuff tendons.
For most conditions causing pain when lifting the arm, the primary non-surgical treatment is physical therapy. A physical therapist will prescribe specific exercises to strengthen the rotator cuff and the muscles around the shoulder blade, improving stability and movement. If pain is not responding to therapy, treatments may progress to corticosteroid injections to reduce inflammation. Surgery is reserved for cases where non-surgical methods fail or for large rotator cuff tears.