Shoulder Impingement Syndrome: Symptoms and Treatment

The shoulder is the joint with the widest range of motion in the body — yet this flexibility also makes it prone to impingement and wear problems. Shoulder impingement, known medically as impingement syndrome, is one of the most common causes of shoulder pain in adults. If you feel a sharp, stabbing pain when raising your arm, wake up at night because of pain, or struggle with simple movements such as reaching for a shelf, this picture may point to shoulder impingement. In this article, I have summarized the causes and symptoms of impingement syndrome, its relationship with the rotator cuff, and the treatment options ranging from physical therapy to arthroscopic surgery.

What Is Shoulder Impingement Syndrome?

In the shoulder, there is a narrow space between the upper end of the arm bone and a bony projection called the acromion, which forms the roof of the shoulder. Passing through this space are the group of tendons we call the rotator cuff, along with a small protective sac called the bursa. When the arm is raised, this space naturally narrows. If the space is structurally narrow, if a bone spur develops on the acromion, or as a result of repetitive overhead movements or poor posture, the tendons and bursa can become pinched in this tight area. Repeated pinching can lead to inflammation of the bursa, swelling in the tendon, and wear over time. This is the condition we call shoulder impingement, or impingement syndrome.

What Are the Symptoms of Shoulder Impingement?

Symptoms usually begin insidiously and increase over time. The findings we encounter most often on examination are:

• Pain when raising the arm above shoulder level, becoming most noticeable within a certain range of motion (the painful arc)
• Pain that worsens at night, makes lying on the affected shoulder difficult, and can wake you from sleep
• Difficulty with everyday movements such as combing your hair, washing your back, or reaching into a back pocket
• Pain felt at the front and side of the shoulder, sometimes radiating down the arm
• A feeling of weakness when raising the arm in later stages

Why Is Night Pain Important?

Night pain is one of the most typical complaints of shoulder impingement. It is thought that changes in the pressure on the tissues around the shoulder while lying down contribute to greater irritation of the inflamed bursa and tendons. A considerable number of my patients come in saying, 'I manage during the day, but at night I can't roll onto that shoulder.' Shoulder pain that wakes you from sleep and has become a regular occurrence should definitely be evaluated by a physician.

Is an Inability to Raise the Arm Always Impingement?

No. Difficulty raising the arm can also be seen in other conditions, such as frozen shoulder, calcific tendinitis, or a rotator cuff tear. In impingement syndrome, the arm usually cannot be raised because of pain, whereas in full-thickness tendon tears a marked loss of strength is the dominant feature. We make this distinction using the examination findings and, when needed, imaging methods such as MRI.

The Relationship with the Rotator Cuff

The rotator cuff is the collective name for the structure formed by the tendons of four muscles that wrap around the shoulder joint like a cuff and allow us to raise and rotate the arm. Impingement syndrome and rotator cuff problems are often different stages of the same process. Long-standing impingement can first lead to swelling and inflammation in the tendon and, over time, set the stage for thinning of the fibers and partial tears. That is why treating shoulder impingement early is important not only to relieve pain but also to protect the rotator cuff.

“Early treatment of shoulder impingement aims not only to ease today's pain but also to protect tomorrow's tendon health.”

How Is It Diagnosed?

The foundation of diagnosis is a careful physical examination. We use special tests to determine which movements trigger the pain and measure your shoulder strength and range of motion. X-rays are used to evaluate the shape of the acromion and any bone spurs; when necessary, an MRI provides a detailed look at the condition of the tendons and the bursa. The aim is to distinguish simple impingement from an accompanying rotator cuff tear, because the treatment plan is shaped accordingly.

How Is Shoulder Impingement Treated?

The first step in treatment is almost always non-surgical. In the majority of patients, consistently applied conservative treatment can bring significant relief without the need for surgery.

Physical Therapy and Exercise

The backbone of treatment is physical therapy and regular exercise. Alongside measures aimed at reducing pain, exercise programs are used to strengthen the rotator cuff and the muscles around the shoulder blade and to correct posture. During this period, taking a break from overhead activities that aggravate the pain, and using pain relievers for a short time on your physician's advice, support recovery. Significant relief can usually be achieved with a regular program lasting 6-12 weeks; however, staying consistent with the exercises is decisive for how lasting the result will be.

Injection Treatments

When the pain is too severe to allow exercise, a cortisone injection into the area of impingement (the subacromial space) can suppress the inflammation and provide rapid relief in most patients. An injection is not a solution on its own but a bridge that paves the way for physical therapy. To protect tendon health, frequent repetition is not recommended; the number and timing of injections should be decided together with your physician.

Arthroscopic Subacromial Decompression

Surgery may come into consideration for patients whose pain persists despite an adequate course of regular conservative treatment, or who have an accompanying structural problem (such as a prominent bone spur or a tendon tear). Arthroscopic decompression is a minimally invasive (keyhole) operation performed through a few small incisions: the inflamed bursa is removed, and the bone spur pressing on the tendon is shaved down to create more room for the tendon to move freely. If a rotator cuff tear is found during the same session, it can be repaired as well. After keyhole surgery, patients are usually discharged the same day or the next day; with a controlled exercise program, returning to daily life is often possible within a few weeks. Full recovery time varies by individual and by the procedure performed, but may take an average of 2-4 months.

Shoulder pain is a complaint that can become harder to treat when it is put off with the thought that 'it will pass eventually.' If you have shoulder pain that has not resolved for several weeks, interrupts your sleep at night, or makes it difficult to raise your arm, I recommend seeing an orthopedics and traumatology specialist without delay. With an early and accurate diagnosis, most patients regain comfortable use of their shoulder without needing surgery.