Shoulder Pain When Throwing a Ball

Shoulder pain when throwing a ball is not so surprising when you consider the complexity of the shoulder joint and what it takes to perform that motion.

To move your shoulder joint, the muscles, tendons, ligaments, and bones all have to move in a synchronized and stable pattern. Because of this, subtle abnormalities can lead to shoulder pain and discomfort when you are throwing or afterward.

This article reviews the mechanics of the throwing motion and reasons it may cause shoulder pain. It also discusses symptoms of a shoulder problem, what's involved in diagnosis, and how it can be treated.

The Motion of Throwing

The throwing motion is characterized by four distinct phases:

1. Wind-up
2. Cocking
3. Acceleration
4. Follow-through

For effective throwing mechanics, the rotator cuff and other shoulder muscles must sequentially guide these movements.

The labrum must stabilize the ball in the socket of the shoulder. The shoulder blade rotation must coordinate with the arm to ensure mobility.

The throwing motion causes very high torque and acceleration forces that act on the shoulder joint and the muscles, ligaments, and tendons that surround the joint. 

Causes of Pain While Throwing

Pain while throwing may come from the:

• Shoulder blade
• Shoulder joint (cartilage and labrum)
• Rotator cuff muscles and tendons
• Nerves that control the function of the muscles

The shoulder blade is attached to the chest wall with ligaments, muscles, and tendons. The various muscles and tendons that control the movement of the shoulder blade impact movements, including throwing.

Abnormalities of any part of this complex linkage can lead to shoulder dysfunction and ultimately to pain when throwing.

The most common abnormality is tightness of the posterior shoulder capsule, causing a loss of normal internal rotation of the shoulder. If this is causing your pain, you may notice that when you reach behind your back, you can't reach up as high on the side with the painful shoulder.

Symptoms of a Shoulder Problem

Whether you're a professional baseball pitcher or playing catch with your child in the yard, shoulder-function abnormalities can cause significant pain. 

Some symptoms of a shoulder problem include:

• Aching pain: Often deep in the shoulder or extending down the upper arm
• "Dead arm": Lack of strength in the throwing motion
• Night pain: Pain isn't too bad when throwing but can awaken you from sleep

Diagnosis

When you go to your healthcare provider to get help for your shoulder pain that's associated with throwing, they'll need to understand exactly where the abnormality is in the throwing motion.

It's helpful to find a healthcare provider who is familiar with throwing mechanics and shoulder injuries. They can best determine if there is a structural abnormality that needs to be addressed.

Your provider will ask about your symptoms and perform a physical examination.

Diagnostic Tests

Tests to diagnose shoulder pain can be helpful, but only when placed into the context of the symptoms you're experiencing.

Often, abnormalities may be seen on a magnetic resonance imaging (MRI) test, but these may or may not be the source of shoulder pain. 

Treatment

Most people who experience the spontaneous onset of pain with throwing can improve with non-surgical treatments. The earliest phase of treatment is resting the joint and reducing inflammation. 

Treatments may include:

• Ice
• Anti-inflammatory medications
• Cortisone injection

Once the acute symptoms of inflammation have subsided, it's important to address the source of the discomfort.

Treatment can be targeted to the problem. Usually, a physical therapist can guide you back to full shoulder mobility and strength. 

Physical Therapy

One of the most common scenarios is when a person who doesn't regularly throw develops pain after an unusual amount of throwing, such as for recreational sports or coaching a children's program.

A structured shoulder stretching and strengthening program almost always alleviates the pain in these cases. Physical therapists often focus on scapular mobility when managing shoulder joint problems.

Exercises may involve:

• Stretching to improve internal rotation or any other lost motion can help allow a more normal throwing motion.
• Strength exercises are often aimed at the rotator cuff, as these muscles initiate proper shoulder movements and stabilize the shoulder joint. 
• Maintaining flexibility of the periscapular muscles (muscles that attach to the scapula bone) is important to ensure that the scapular movements are coordinated with the throwing motion.
  

Most cases of shoulder pain when throwing will improve with supervised therapy. 

Summary

The throwing motion is a complex shoulder movement that requires normal mechanics of interconnected muscles, tendons, ligaments, bones, and joints.

When the mechanics of the throwing motion are altered, inflammation is often the result, and discomfort is a frequent symptom.

The good news is that noninvasive treatments to improve the mechanics of the shoulder joint are often effective at relieving symptoms of shoulder pain when throwing.