Shoulder Pain When Throwing

The motion of throwing a ball is a complex movement that requires a healthy functioning shoulder where muscles, tendons, ligaments, and bone all move in a synchronized and stable pattern.  Because of the complexity of this movement, subtle abnormalities can lead to the development of shoulder pain and discomfort. 

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.  Whether you are a professional baseball pitcher, or playing catch with your child in the yard, abnormalities of shoulder function can cause significant pain.  Some of the signs of a shoulder problem include:

• Aching Pain: Often deep in the shoulder or extending down the upper arm
• "Dead Arm:" A sensation of lack of strength of the throwing motion
• Night Pain: Sometimes the pain is not too bad when throwing, but causes pain that can awaken you from sleep at night

When people complain of a shoulder pain when throwing, it's critical to understand exactly where in the throwing motion there is an abnormality, and what might be causing this problem.  The most useful methods to make the diagnosis are actually carefully understanding the patient's symptoms and examining the shoulder by someone familiar with throwing mechanics.

Tests to diagnose shoulder pain can be helpful, but only when placed into the context of the symptoms experienced by the patient.  Often in both young athletes and middle-aged weekend warriors, abnormalities may be seen on an MRI, but these may or may not be the source of shoulder pain.  That's where a skilled examiner familiar with shoulder injuries can help to determine if there is a structural abnormality that needs to be addressed.

The throwing motion is characterized by four distinct phases:

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

In order 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 must rotate in a coordinated motion with the arm to ensure mobility.  Abnormalities in any of these functions can lead to pain and even damage inside the shoulder. 

One of the often neglected aspects of shoulder mobility is the function of the shoulder blade. The shoulder blade includes the socket of the ball-and-socket shoulder joint.  In order for the ball-and-socket to function normally, the shoulder blade must also function normally. The shoulder blade is attached to the chest wall with ligaments, muscles, and tendons. The various muscles and tendons that control movement of the shoulder blade can all impact movements including throwing. This is one of the reasons why physical therapist often focus on scapular mobility when addressing shoulder joint problems

Most patients who experience the spontaneous onset of pain with throwing can be managed with non-surgical treatments.  The earliest phase of treatment is to rest the joint and reduce inflammation.  Treatments such as ice, anti-inflammatory medications, and even a cortisone injection may be helpful to allow inflammation to subside.

Once the acute symptoms of inflammation have subsided, a therapist can guide an athlete to regain full mobility and strength of the shoulder.  The most common abnormality is tightness of the posterior shoulder capsule, causing a loss of normal internal rotation of the shoulder (patients may notice when they reach behind their back, they can't reach up as high on the side with the painful shoulder).  Stretching to improve internal rotation, or any other lost motion, can help allow a more normal throwing motion.

Strength is often aimed at the rotator cuff, as these muscles are critical to initiating proper shoulder movements, and also stabilizing the shoulder joint.  In addition, the periscapular muscles (muscles that attach to the scapula bone) are important to ensure that the scapular movements are coordinated with the throwing motion.

As stated, most cases of shoulder pain when throwing will improve with these steps.  The mechanics of the shoulder are very complicated, and subtle abnormalities can cause disruption of this complex motion.  By improving the mechanics, most cases of shoulder pain can improve with noninvasive treatment.  Patients who fail to make improvement with 3 months of therapy, or fail to return to competitive sports within 6 months, may be considered for a surgical procedure.  However, it should be clear about what problem needs to be addressed, and how that will improve the throwing mechanics, before embarking on a major shoulder surgery.

The throwing motion is a complex shoulder movement that requires normal mechanics of interconnected muscles, tendons, ligaments, bones, and joints. Abnormalities of any part of this complex linkage can lead to shoulder dysfunction and ultimately to pain when throwing. 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.