Shoulder pain at night is common, frustrating, and disruptive. Understanding where the pain may be coming from is the first step toward finding relief.
Where is my shoulder pain coming from?
Whether it started after an injury, developed gradually, or appeared without a clear cause, several structures in the shoulder can contribute to night pain. The most common sources include the rotator cuff, shoulder joint, joint capsule, biceps tendon, and AC joint.
- The Rotator Cuff
The rotator cuff is a group of tendons that helps lift and rotate the arm. Because these tendons pass through a narrow space near the top of the shoulder, they can become irritated or pinched, especially with overhead activity. Over time, wear and tear can make that space smaller, increasing inflammation and pain.
- Glenohumeral Joint (Shoulder Arthritis)
Cartilage cushions the ends of the bones so they can glide smoothly against each other. Over time, previous injury, repetitive use, age, and genetics can contribute to cartilage wear. When the joint becomes irritated or arthritic, pain may be more noticeable at night, especially when lying on the affected shoulder. Shoulder arthritis can also cause stiffness, decreased range of motion, catching, or locking. A classic pattern to look for is “start-up” pain: stiffness or discomfort when you first wake up that improves as the day goes on.
- Joint Capsule (Frozen Shoulder)
Frozen shoulder is an inflammatory condition that affects the lining of the shoulder joint. It can cause significant pain and a noticeable loss of motion, including difficulty moving the shoulder on your own or having someone else move it for you.
- Biceps Tendon Injuries
The long head of the biceps tendon attaches deep inside the shoulder near the labrum, then travels down the front of the upper arm through a small groove. When this tendon becomes irritated or inflamed, it can cause pain in the front of the shoulder and may be aggravated by certain arm movements.
- Acromioclavicular (AC) Joint
The AC joint sits at the top of the shoulder where the collarbone meets the shoulder blade. Irritation or arthritis in this joint can cause pain on top of the shoulder, especially with reaching, lifting, or lying on that side.
Why Is My Shoulder Pain Worse at Night?
Less Distractions
During the day, movement and activity can distract from pain. When you get into bed at night and distractions fade, shoulder discomfort can feel more noticeable.
Compression
Lying on the affected side can place added pressure on an already irritated joint, tendon, or bursa. That extra compression may aggravate symptoms and make it harder to stay comfortable.
Inflammation Cycle
Nighttime pain does not always mean the shoulder is being damaged while you sleep. In many cases, pain feels worse because inflammation and pain sensitivity can increase overnight while the body’s natural anti-inflammatory response goes down. Poor sleep can then make the body more sensitive to pain the next day, creating a cycle of pain, disrupted sleep, and more pain.
Does my Shoulder Pain Mean I Have a Tear?
Not necessarily. Night pain can be caused by several different shoulder problems, and a tear is only one possibility. A thorough evaluation, physical exam, and X-rays are often a good starting point. If more detail is needed, an MRI can help evaluate the soft tissues, including the rotator cuff.
What Can I Do About It?
The good news is that many causes of nighttime shoulder pain can be treated without surgery. Depending on the source of the pain, simple changes may help reduce irritation and improve sleep.
- Rest, ice, or heat
- Oral anti-inflammatory medication
- Avoid overhead activity
- If you tend to sleep on your sore side, try to sleep on your back or the other shoulder
- Make sure your pillow is supportive
If pain continues for several weeks, worsens, or follows a significant injury, it may be time to see a specialist. Persistent symptoms can sometimes point to issues such as advanced arthritis, tendon inflammation, or a rotator cuff tear.
How Can I Tell if My Night-Time Pain Is Serious?
- The pain has persisted for several weeks and is not improving
- You have weakness, loss of motion, or difficulty with daily activities
- You had a recent fall or injury to the shoulder
- You have swelling, catching, or locking in the joint
Don’t Just Live with It
If shoulder pain is keeping you from sleeping well or doing the activities you enjoy, you do not have to simply live with it. A shoulder specialist can help identify the cause of your pain and recommend a treatment plan to help you get back to more restful nights.
Schedule a shoulder evaluation with Dr. Andrew P. Mahoney at The Oregon Clinic Orthopedics in Beaverton or Portland.