Shoulder Impingement Syndrome
Shoulder impingement syndrome (SIS) is a common cause of shoulder pain in adults. People with the condition experience pain related to the shoulder's tendons and soft tissues when lifting the arm overhead.
The extension of bone at the top outer edge of the scapula (shoulder blade) is called the acromion. When someone lifts their arm overhead, the space between the acromion and humeral head (top of the upper arm bone) gets smaller. In this space are the rotator cuff, biceps tendon and bursa (sac of cushioning fluid). Compression (impingement) of these structures causes pain and limits movement.
Inflammation of the bursa (bursitis) or of the tendons of the rotator cuff or biceps (tendinitis) is painful. Over time, degenerative changes can occur in the tendons (tendinosis). In some circumstances, repeated rotator cuff impingement can cause partial tears in the tendons. These may even lead to larger or complete tears over time.
Repetitive arm movements, particularly those performed overhead during certain sports – such as swimming, volleyball or tennis – can increase the likelihood of developing SIS. This pain may also develop as a result of a minor event in which there is impact, such as a fall onto the shoulder or outstretched hand. In some cases, the problem has no obvious cause.
Our approach to shoulder impingement syndrome
Many patients with SIS get better with rest and physical therapy. Pain medications can also be useful, and in some cases, cortisone injections into the shoulder joint can reduce pain and swelling, aiding recovery.
If the pain persists and specific structures require attention, surgery is an option. For these patients, our team includes orthopedic surgeons who specialize in the shoulder and physical therapists who focus on working with orthopedic and sports medicine patients. These experts work together to relieve pain and restore mobility, so patients can return to their normal lives and favorite activities.
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Signs & symptoms
People with SIS may experience:
- Pain and weakness in the shoulder – particularly when lifting heavy objects above shoulder level
- Decreased range of motion – which may interfere with performing everyday tasks, such as getting dressed and washing hair
- Trouble sleeping
To diagnose SIS, a doctor will review your symptoms and perform a physical exam.
X-rays or an MRI of the shoulder can also be useful. An MRI may show fluid or inflammation in the area. In some cases, partial tearing or other damage involving the rotator cuff and surrounding structures are visible.
Initial treatment of SIS generally involves conservative measures such as physical therapy and pain-relieving medications. Most patients benefit from a course of physical therapy focused on stretching the shoulder and strengthening the rotator cuff and scapular muscles, as well as postural exercises to address the position of the shoulder blade.
Doctors often prescribe a course of nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen. Another anti-inflammatory option may be to inject a local anesthetic and cortisone into the shoulder. Platelet-rich plasma injections are a more recent treatment that some patients consider, though many insurance plans do not cover them.
For patients whose pain doesn't respond to conservative measures, our orthopedic surgeons have expertise in shoulder impingement. As with any kind of surgery, there are risks and possible complications, so we generally explore these options only if nonsurgical therapies have failed.
In the most common surgical treatment, a minimally invasive procedure called subacromial decompression, the goal is to relieve the compression on the rotator cuff and bursas by creating more space between the humeral head and the acromion. Performed with an arthroscope (an endoscope for use in joints), the surgeon passes a tiny camera and slender instruments through a small incision and removes the portion of the acromion causing impingement along with some of the bursas. If the shoulder has other conditions needing repair (such as a rotator cuff tear), the surgeon may address these at the same time.
To facilitate healing, patients usually use a sling for the first one to two weeks after surgery. During that time, they shouldn't drive. After this period, they begin a physical therapy program, focusing first on regaining passive range of motion and later on active range of motion. Between six and eight weeks after surgery, patients can progress to strengthening exercises, and a full return to activities is generally achieved three to four months after surgery.
Frequently asked questions
- When can I shower after surgery?
You'll need to keep the incision clean and dry until your first post-op visit, one to two weeks after surgery. At that time, you'll likely be cleared to shower, but don't submerge the surgical site in a bathtub or swimming pool until three to four weeks have passed since your surgery.
- When can I drive after shoulder impingement surgery?
You'll be wearing a sling and unable to drive for one to two weeks. You may resume driving after that, so long as you have appropriate control to do so safely.
- When can I return to my usual activities?
In general, people are able to resume most activities about three months after shoulder impingement surgery.
- When can I return to school or work?
Most people can return to school or desk work about two weeks after surgery. If you have a physically demanding job, you'll need more time for a full recovery and medical clearance before returning.
UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.