What Causes Infraspinatus Pain and How Can I Treat It?

The infraspinatus is one of four muscles that make up the rotator cuff, which helps your arm and shoulder move and stay stable.

Your infraspinatus is in the back of your shoulder. It attaches the top of your humerus (the top bone in your arm) to your shoulder, and it helps you rotate your arm to the side.

Pain in the infraspinatus is most likely caused by repetitive motion involving the shoulder. Swimmers, tennis players, painters, and carpenters get it more frequently. It also becomes more likely as you get older.

There are several potential causes of infraspinatus pain. Some are serious, but none are life threatening.

Infraspinatus muscle pain causes

Sometimes, infraspinatus pain is due to minor strains or wear and tear. In these cases, rest will likely relieve the pain. But your pain may also be caused by an injury or more serious conditions.

Infraspinatus tear

There are two types of infraspinatus tears:

  • A partial tear will damage the tendon, but it doesn’t go all the way through. It’s usually caused by repetitive stress or normal aging.
  • A complete, or full- thickness, tear severs the infraspinatus from the bone. It’s usually caused by an acute injury, such as falling.

Infraspinatus tendinopathy

Infraspinatus tendinopathy is a less severe injury to the infraspinatus. There are two types:

  • Tendonitis is an inflammation of the tendon.
  • Tendinosis is small tears in the tendon that don’t cause much inflammation.

Causes of tendinopathy include:

  • overuse, especially reaching overhead or throwing
  • shoulder trauma
  • arthritis or another inflammatory disease in your shoulder
  • normal wear and tear as you age

Infraspinatus impingement

Impingement is when a tendon gets compressed, usually by a bone spur or inflammation. Infraspinatus impingement is uncommon in people who aren’t in sports that involve overhead throwing, such as tennis. It’s particularly common in athletes under age 30.

Bursitis

Bursitis occurs when the bursa — a fluid-filled sac between the top of your arm bone and the tip of your shoulder — becomes inflamed. This can cause pain and restrict the infraspinatus muscle’s movements.

Overuse is the most common cause of bursitis, but it can also be caused by:

  • arthritis
    • gout
  • diabetes
  • thyroid disease
  • tendonitis
  • acute injury

Pinched nerve

If the suprascapular nerve in your shoulder gets pinched, it can cause infraspinatus pain. A pinched nerve is usually due to trauma, overuse injuries, or as a result of other shoulder dysfunction.

What are infraspinatus trigger points?

Trigger points — which not all doctors believe actually exist — are thought to be hard, tender spots in a muscle.

Latent trigger points hurt when they’re pushed on, while active trigger points cause pain even without touch or motion. They can cause not only pain, but restrict motion and cause muscle weakness.

Active trigger points can cause pain at the spot in the muscle or referred pain. Referred pain is pain in other areas of the body, usually ones near the trigger point.

Trigger points are usually activated by stress on the muscle. If you have active trigger points in your infraspinatus, it can cause pain in your shoulder and down your arm.

Treatment may include:

  • dry needling
  • anesthetic injections
  • stretching
  • massage
  • laser therapy
  • nonsteroidal anti-inflammatory drugs (NSAIDs)

Diagnosing infraspinatus pain

To diagnose the cause of your infraspinatus pain, a doctor will first take a look at your medical history. They’ll ask you about:

  • your symptoms
  • when the symptoms started
  • any recent injuries
  • if you play sports or have other activities with repetitive shoulder motion

Then, they’ll do a physical exam to see what motions hurt your shoulder, if your range of motion is limited, and if your shoulder muscles seem weak.

Usually, a medical history and physical exam are enough to diagnose an infraspinatus problem. But a doctor may also do an X-ray to rule out other possibilities or an ultrasound or MRI to confirm a diagnosis.

If a doctor isn’t sure whether you have an infraspinatus tear or tendinopathy, they may inject the muscle with a local anesthetic. If you have tendinopathy, the pain will improve and your muscle strength will be normal. If you have a tear, your arm function will still be limited.

Infraspinatus pain test

An infraspinatus pain test is used to see whether your pain is coming from the infraspinatus or another part of your shoulder.

You’ll bend your arms 90 degrees, with your palms facing up. Your elbows should be at your sides, and your arms should be out in front of you.

A doctor will push against your arms while you rotate them outward. If this hurts, you most likely have an infraspinatus problem.

Treating the causes

In most cases, a doctor will recommend trying nonsurgical treatment for infraspinatus pain. These treatments are successful for most people, although a combination of nonsurgical treatments may be necessary.

If nonsurgical treatment isn’t effective, surgery may be an option.

Rest

Infraspinatus injuries are often caused by repetitive motion. Resting your shoulder will give it a chance to heal. A doctor might recommend resting your arm in a sling or temporarily avoiding activities that cause more pain.

Heat and ice

Icing your shoulder will reduce inflammation. You can do this early on in your injury or after you exercise or stretch.

Heat will help relax your infraspinatus. You should apply heat before stretching or exercising. Using a heating pad or taking a warm bath or shower are effective.

Infraspinatus pain stretches and exercises

Stretches and exercises will help you improve flexibility and range of motion. They’ll also help you strengthen your muscles to avoid further injury. None of these stretches or exercises should cause pain. If they do, stop and tell your doctor.

A doctor may also recommend physical therapy. They can give you additional exercises to do at home.

Here are some exercises you can try:

Pendulum

This exercise helps stretch your muscles and the space they pass through so that you don’t get a frozen shoulder.

  1. Lean forward at an angle. Use your nonaffected arm for support.
  2. Slowly swing your affected arm forward and backward, then side to side.
  3. Then move it in small circles.
  4. Do 2 sets of 10 of each.

External rotation

This exercise helps strengthen and stretch your infraspinatus. As you heal, you can start adding weights.

  1. Lie on your side and rest your head on your arm
  2. Bend the arm you’re not lying on 90 degrees so your elbow is in the air, your hand is on the ground, and your arm is running across your stomach.
  3. Keep your elbow at your side and slowly rotate your arm. It should end up bent 90 degrees with your hand in the air.
  4. Slowly rotate the arm back down.
  5. Do 2 sets of 10.
  6. Repeat on the other side.

Passive external rotation

You should feel this stretch in the back of your shoulders. You’ll need a light stick, like a yardstick or broom handle.

  1. Loosely grab the stick on each end.
  2. Keep the elbow of your affected arm against your body.
  3. Use the other arm to gently push the stick horizontally so that the affected elbow is against your side and the affected arm is bent 90 degrees, perpendicular to your body.
  4. Hold for 30 seconds.
  5. Relax for 30 seconds.
  6. Repeat 3 more times.
  7. Repeat on the other side.

NSAIDs

NSAIDs like ibuprofen (Advil, Motrin) relieve pain and reduce swelling caused by your injury.

Steroid injections

Steroid injections use a mix of local anesthetic and cortisone, which is an anti-inflammatory steroid. Your doctor will inject this mix directly into your infraspinatus or bursa, depending on your specific condition.

These injections can provide temporary relief, but can damage your muscle if done too often.

Surgery

Surgery can be done for severe injuries or if other treatments have failed. It’s typically only done as a first treatment if you have a severe, acute injury, such as a complete tear from a fall.

There are different types of surgery. Your doctor should discuss your options with you.

Recovery and outlook

Your doctor will most likely recommend rest, exercises, and stretching first. If those don’t start to help within a few weeks, you should go back to your doctor for further evaluation.

At this point, they may recommend continuing exercises or give you a steroid injection. Injections usually start working to decrease pain within a few days.

If you still have pain after 6 months, your doctor might see if you’re a good candidate for surgery. Open surgery, which uses one large incision, has a longer healing time than arthroscopic surgery, which uses several small incisions.

It usually takes approximately 6 months before your shoulder function will return to normal after surgery. Depending on how well you’re healing, you can likely return to some activities within 4 months.

Takeaway

Infraspinatus pain can be a sign of a serious condition. But in most cases, it can be resolved with treatments such as rest, stretching, and NSAIDs.

If you have shoulder pain and weakness, especially if you do a lot of repetitive arm motions in your daily life, talk to your doctor. They can help you find the cause of your pain and treatment options.

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