Not being able to lift our arm because of shoulder pain is very common. Shoulder pain can be one of the more annoying and painful conditions. For many of you, you simply woke one morning and your shoulder hurts. Often that pain in on the top of the shoulder or the side of the shoulder. Some of you might have severe pain when trying to sleep and others might only have shoulder pain when trying to lift the arm. These are not unusual issues when it comes to shoulder pain. Most of you will not recall a shoulder injury. Most did not change their workouts or start to exercise more aggressively. In most instances, you are 40-60 years old, and this might be your dominant or your non-dominant arm. Because this is such a common problem that I see the my office everyday we are going to review the more common reasons that will cause:
- Pain on top of the shoulder
- Shoulder pain when lifting the arm
- Causes of stiffness and difficulty in moving your shoulder.
There are many problems that can occur in the shoulder that can make it difficult or too painful when trying to lift or move your arm. More often than not this is due to an issue with the rotator cuff (see list below). The rotator cuff is the most common cause of pain in the adult shoulder. Rotator cuff pain is the number one reason why you have pain on the outside or top of your arm. It is also the main reason why you may not be able to lift or have pain when you move your arm.
Shoulder pain could also be brought on by injury. Believe it or not, traumatic injuries are a less frequent cause shoulder pain. Rotator cuff injuries can be caused by chronic repetitive stress from working out, throwing or overhead sports. Rotator cuff injuries can also be caused by a fall, or perhaps even a long day gardening or painting your house.
The rotator cuff are a series of four muscles that are deep to or underneath your deltoid muscle. Together those four muscles control your shoulder motion and are critically important to the proper functioning of the shoulder.
If the rotator cuff is injured, inflamed, strained or torn, you may find that you are unable to lift your arm. Common rotator cuff issues that hurt when we raise our arm include:
- rotator cuff tendonitis
- rotator cuff tendinosis
- rotator cuff tears
- partial rotator cuff tears
- calcific tendonitis
- adhesive capsulitis or a frozen shoulder
The cause of your shoulder pain and the reason why it hurts will vary by age. Some problems are more common in different age groups. In younger athletes tendonitis is more common. In middle age, rotator cuff tendinosis, calcific tendinitis, AC Joint arthritis and a frozen shoulder are more common causes of pain. Let’s run through the most common reasons why you have pain on the top or side of your shoulder and why you have pain when trying to lift your arm.
Rotator Cuff Tendinosis
In people over 30 rotator cuff tendonitis is very rare and rotator cuff tendinosis starts to become the most common cause shoulder pain which hurts when we try to lift our arm or shoulder. 
Rotator cuff tendinosis, by definition implies some degree of rotator cuff degeneration. With that degeneration comes an increase in the numbers of nerves and blood vessels. That is the body’s response to the degeneration, and that is why the pain occurs. Too many nerves in the area produces pain with certain motions. If the pain is severe enough you will be unable to raise your arm or unable to sleep on that side.
When patients have rotator cuff tendinosis, physical therapy is generally effective at managing the pain. If the pain persists despite therapy, we now have a biological patch which may be able to reverse tendinosis and alleviate your shoulder pain.
Many people who cannot lift their arm due to shoulder pain from rotator cuff tendinosis will be told that they have impingement syndrome and a bone spur. This video post discusses our current thoughts on bone spurs and shoulder pain. These posts here, here, and here go into far more detail about rotator cuff tendinosis.
Partial Rotator Cuff Tears
As the rotator cuff continues to age or degenerate a portion of the rotator cuff might separate from the bone that it is normally attached to. This is usually part of the natural progression of tendinosis. If enough of the rotator cuff starts to separate then we have a small cleft or defect in the rotator cuff attachment. We call that a partial tear. Partial tears are not large enough to cause weakness of the shoulder. However, if you have a painful partial tear, you can have pain on top or on the side of the shoulder. In addition, you may find it very painful when trying to lift the arm overhead.
Some partial tears hurt, while others do not. Determining if your partial tear is painful is usually possible with a physical exam. Most people with partial tears of the rotator cuff are going to respond to physical therapy. If physical therapy and other non-surgical treatments do not improve your pain, then surgery to place a unique biological patch has a very high likelihood of alleviating your night pain and pain with lifting your arm. See this post for more information about the patch and how it works.
Traumatic Shoulder Pain
Some of you are reading this because you fell on your shoulder and now you can not move your arm. In acute traumatic situations like this, there is a chance that you ripped the rotator cuff off from the bone. If you fell, and now have significant weakness in your arm you should see an Orthopedic Surgeon soon. This post covers what to look for if you think you had a serious shoulder injury.
The rotator cuff controls how well the shoulder functions. If your injury caused a rotator cuff tear, your complaints and symptoms may be related to the size of the rotator cuff tear. If enough of the rotator cuff has torn then it might be impossible to move your arm due to severe weakness. Many people with acute, large, traumatic rotator cuff tears will require surgery in order to restore function. In general, the treatment of rotator cuff tears depends on the cause of the rotator cuff tear and I go into more detail in these posts here and here.
