What is Shoulder Impingement?

Shoulder impingement is a common condition that can cause pain and discomfort in your shoulder. It happens when the tendons or bursa in your shoulder become irritated or compressed. This often occurs because of repetitive movements or overuse, such as lifting, throwing, or swimming. Additional terms utilized to describe impingement include swimmer’s shoulder, tennis shoulder, and rotator cuff tendinitis.

Anatomy of Shoulder Impingement

The most common type of shoulder impingement is also called “subacromial impingement.” This refers to the anatomical structures of the rotator cuff tendons (particularly the supraspinatus tendon), the subacromial bursa, and the acromion (part of the shoulder blade or scapula). The issue arises in the subacromial space, which is the narrow space between the acromion and the rotator cuff tendons.

What Causes Shoulder Impingement?

Several things can lead to shoulder impingement, including:

1. Subacromial Space Narrowing: The space between the acromion and the rotator cuff tendons becomes too narrow. This can happen due to:

2. Altered Shoulder Mechanics:

3. Compression of Tendons and Bursa:

   1. Inflammation or swelling: The rotator cuff tendons or the subacromial space may become inflamed and swollen, reducing the space available causing compression.

   2. Shape of the Acromion: Some people naturally have an acromion that is more curved or hooked, which can predispose them to impingement.

   3. Bone Spurs: Bony growths on the underside of the acromion can develop, further narrowing the space.

1. Overuse: Repeated use of the shoulder, especially in activities that involve lifting the arm overhead, can irritate the tendons and bursae.

2. Injury: A fall or sudden injury can cause inflammation or swelling in the shoulder.

3. Aging: As we age, the tendons in the shoulder can wear down or become less flexible.

4. Anatomy: Some people naturally have a narrower space in the shoulder, making them more prone to impingement.

Common Symptoms

• Pain: Often felt on the top or outside of the shoulder, especially when lifting the arm or reaching behind.

• Weakness: Difficulty lifting or reaching for objects.

• Limited Range of Motion: Trouble moving the shoulder freely.

• Tenderness: The area may feel sore to the touch.

Diagnosis

A healthcare provider can diagnose shoulder impingement through a physical exam and may use imaging tests like X-rays or MRI if needed.

Treatment Options

• Rest: Avoid activities that cause pain.

• Ice and Heat: Applying ice can reduce inflammation, while heat can relax muscles.

• Medication: Over-the-counter pain relievers can help manage pain and inflammation.

• Physical Therapy: Exercises can strengthen shoulder muscles and improve flexibility.

• Injections: Corticosteroid injections can reduce inflammation and pain.

• Surgery: In severe cases, surgery may be needed to create more space in the shoulder and relieve pressure on the tendons and bursae.

Prevention

• Proper Technique: Use the right form when doing activities that involve the shoulder.

• Warm Up: Stretch and warm up before physical activities.

• Strengthening Exercises: Regular exercises can help keep shoulder muscles strong and flexible.

When to See a Doctor

If you experience persistent shoulder pain or difficulty moving your arm, it's important to consult with a healthcare provider. They can help determine the cause of your symptoms and recommend appropriate treatment.

Remember, shoulder impingement is a common and treatable condition. With the right care and attention, most people can recover and return to their usual activities

Here's a breakdown of the anatomical changes and issues:

1. Subacromial Space Narrowing: The space between the acromion and the rotator cuff tendons becomes too narrow. This can happen due to:

   • Inflammation or swelling: The rotator cuff tendons or the subacromial bursa may become inflamed and swollen, reducing the space available and causing compression.

   • Bone spurs: Bony growths on the underside of the acromion can develop, further narrowing the space.

   • Shape of the acromion: Some people naturally have an acromion that is more curved or hooked, which can predispose them to impingement.

2. Compression of Tendons and Bursa: When the arm is lifted, the rotator cuff tendons and the subacromial bursa can become compressed or pinched between the acromion and the humeral head (the ball part of the shoulder joint). This repeated compression can lead to:

   • Irritation and inflammation: The tendons and bursa can become irritated and inflamed, leading to pain and swelling.

   • Tendon degeneration: Over time, the repetitive compression can cause wear and tear on the tendons, potentially leading to tendinopathy or even rotator cuff tears.

3. Altered Shoulder Mechanics: The pain and inflammation can lead to changes in shoulder mechanics. To avoid pain, a person may alter the way they move their shoulder, which can lead to weakness, stiffness, and reduced range of motion.

In summary, shoulder impingement involves a narrowing of the subacromial space, which leads to the compression of the rotator cuff tendons and the subacromial bursa. This compression can cause pain, inflammation, and potential damage to the tendons and bursa.