Posts

Regaining Shoulder Range of Motion in Baseball Players

Regaining motion following heavy doses of high intensity throwing cannot be overlooked.

Throwing causes significant range of motion changes from eccentric stress. Any movement activity causing significant muscle damage can alter movement in the days following.

Pitchers throwing a large amount of pitches suffer significant eccentric stress, not only in the arm/shoulder but throughout the entire body. Joint distraction forces at the shoulder and elbow rapidly increase to 1–1.5 times the body mass to decelerate the arm.

Mike Reinold, in a 2008 study, showed significant decreases in shoulder internal rotation, total motion, and elbow extension following pitching in the dominant shoulder.  These changes were noted immediately post pitching and continued to exist 24 hours after.  These motion losses begin acutely but can progress into long term alterations.

Many of us in the baseball field have long known about glenohumeral internal rotation deficit (GIRD) when it comes to the throwing shoulder, but several recent studies are linking injuries to other movement loss within the glenohumeral joint.

Over 6 years, Dr. Chris Camp and others studied range of motion on all invited pitchers from one professional organization, totaling 81 pitchers followed and accounting for 132 pitcher seasons.

The authors looked at shoulder flexion, horizontal adduction, external rotation, internal rotation, as well as elbow flexion and extension in both the dominant and non-dominant arm during the pre-season.

Out of the 53 injuries they encountered over the 6-year period, the most significant risk factors for elbow injury were loss of shoulder external rotation and loss of shoulder flexion. Injury risk at the elbow went up 7% for each degree of external rotation loss and 9% for each degree of flexion loss.

None of the range of motion measures correlated with shoulder injuries. The study shows that altered kinematics at the shoulder have a significant effect down the kinetic chain at the elbow.

In the Camp study, the presence of an internal rotation deficit did not correlate to any increased risk of shoulder or elbow injuries.

However, the predominant overall theme remains in that pitching causes significant stresses to the arm and body, and that stress can cause significant motion losses. Motion losses are regularly tied into shoulder and arm injuries.

Regaining full overhead capacity can be much more than simply soft tissue restrictions but an easy place to start is by mobilizing the tissue around the scapula and shoulder. Gaining full overhead motion can be a combination of many factors, and it often starts at form and function when it comes to global movement.

Body and anatomical positions determine form and form dictates function.  The pelvis stuck in a poor position affects the lumbar spine which affects the thoracic spine orientation which 100% affects the scapular position which affects the shoulder.  The following list to regaining overhead motion is a good place to start but is not an exhaustive list by any means.

 

Positions – Form and Function

1. Pelvic control

Pelvic control in my opinion is the foundation of all patterns within the body.  The inability to control the pelvis stems from poor glute and abdominal motor control.

Compensation patterns result from this lack of control in the form of extended spinal positions, especially at the lumbar spine.  An over extended lumbar spine creates the rib-flair up the kinetic chain, and the rib-flair allows for false motion with overhead athletes.

Developing the ability to control the pelvis should be a priority for efficient overhead motion.  Pelvic stability should revolve around the rectus abdominus, obliques, and glute complex.  Teach and train a neutral pelvis along with anti-extension throughout the torso.

 

2. Thoracic Extension

The ability of the t-spine to extend assists in humeral flexion through efficient scapular mechanics.

A poor position places the scapula at a disadvantage.

A forward head posture with excessive rounding of the upper back drives the scapula forward into anterior tilt.

An athlete unable to extend through the t-spine will be unable to effectively upwardly rotate, and posteriorly tilt the scapula resulting in less overhead ability.

A study by Strunce in 2009 showed large increases in shoulder range of motion following thoracic spine and rib manipulations.

Although not on an athletic population, the results demonstrated the immediate benefits of positioning when it comes to the thoracic cage.

Active range of motion at the shoulder improved in flexion by 38° and improved total rotation by 30° after manual manipulation.

Results from another study by Edmonston in 2012 confirmed that extension of the thoracic spine does occur during arm flexion. The ranges of thoracic spine extension with humeral flexion was an average of 12.8 degrees, showing the importance of the kinetic chain in overhead motion.

 

3. Scapular Positioning

For the shoulder to function correctly, it relies on assistance from the scapula to get overhead.  Upward rotation and posterior tilt are significant factors in flexion.

For the arm to get a full 180 degrees of motion, the scapula must contribute 60 degrees while the glenohumeral joint handles the other 120 degrees. Without that 60 degrees, motion is compromised.

Focusing on the lower trap and serratus anterior are a good place to start as both are responsible for upward rotation, while the lower trap is key in posterior tilt.  Both are the most commonly inhibited muscles in overhead athletes due to posture, lifestyle, training methods, etc.

 

4. Soft Tissue Restrictions

Obviously, the muscles attaching to the scapula and humerus play huge roles in not only creating motion but restricting motion as well. Overactive or tight tissues limit motion.

Some muscles that have great influence on scapular positioning and subsequently on motion include the latissimus dorsi, pec major and minor, rhomboids, and levator scapula (to name a few).

Manipulating these common problem areas can go to great lengths in restoring fluid movement and positioning. However, muscles aren’t the only factor.

Capsular restrictions around the glenohumeral joint itself can factor into the equation as well.

 

Soft Tissue for Scapular Upward Rotation

 

T-Spine Extension for Overhead Athletes

 

The “overhead” in overhead athletes tells us all we need to know. The overhead position matters to throwers and being able to get there the right way is key. Don’t let flexion disappear or become a compensation pattern over the course of a long season. Keep moving efficiently for long term health when it comes to the shoulder and elbow.

 

Sources:

Camp, Christopher L., et al. “Decreased Shoulder External Rotation and Flexion Are Greater Predictors of Injury than Internal Rotation Deficits: Analysis of 132 Pitcher-Seasons in Professional Baseball.” Orthopaedic Journal of Sports Medicine, vol. 5, no. 7_suppl6, 2017, doi:10.1177/2325967117s00221.

Edmondston, Stephen, et al. “Clinical and Radiological Investigation of Thoracic Spine Extension Motion During Bilateral Arm Elevation.” Journal of Orthopaedic & Sports Physical Therapy, vol. 42, no. 10, 2012, pp. 861–869., doi:10.2519/jospt.2012.4164.

Reinold, Michael M., et al. “Changes in Shoulder and Elbow Passive Range of Motion after Pitching in Professional Baseball Players.” The American Journal of Sports Medicine, vol. 36, no. 3, 2008, pp. 523–527., doi:10.1177/0363546507308935.

Strunce, Joseph B., et al. “The Immediate Effects of Thoracic Spine and Rib Manipulation on Subjects with Primary Complaints of Shoulder Pain.” Journal of Manual & Manipulative Therapy, vol. 17, no. 4, 2009, pp. 230–236., doi:10.1179/106698109791352102.

 

Why GIRD May Be Normal and a Lack of Internal Rotation May Not Lead to Injury

In the sports medicine world, we not only want to treat deficits the athlete presents with, but more importantly, combat the root of the problem itself. In this way, we can prevent future injuries from occurring in the first place.

If we can improve our understanding of underlying pathology and have a greater appreciation for the factors that truly cause injury, we can really make a positive impact as clinicians. Sounds good, right?

In terms of baseball players, there has been a lot of recent research that has discussed the concept of “GIRD,” or glenohumeral internal rotation deficit, and its role as a potential precursor to injuries, particularly in overhead athletes such as baseball players.

But what if this loss of internal rotation doesn’t really matter in regards to injury, and that other measures, instead, could be more important to understand if a baseball player is at an increased injury risk? Before we dive into that, let’s first take a look at exactly what GIRD is.

 

What is Glenohumeral Internal Rotation Deficit (GIRD)?

According to an older and outdated definition by Kibler, GIRD occurs when an athlete demonstrates “altered shoulder internal and external ranges of motion where internal rotation is decreased and external rotation is increased in the dominant arm when compared to the non-dominant arm.”

Since this early definition, it has become well identified in the literature that this alteration in range of motion may in fact be normal in overhead athletes, such as baseball pitchers. Mike Reinold has an article describing why GIRD may be normal.

Reinold, who has worked with 1000’s of both injured and healthy baseball players, states that he believes that “a loss of side-to-side IR is actually a normal anatomical variation in overhead athletes.”

He continues by stating that GIRD should not be considered pathological unless there is “subsequent loss of total rotational motion in the dominant arm as well.”

Other sources have attempted to define GIRD as occurring when the internal rotation deficit is greater than 20° to that of the non-dominant arm. But even this has limitations as another arbitrary figure.

This newer definition that Reinold has established, works to specific the loss of internal rotation to the athlete themselves in terms of their respective total range of motion, as opposed to an arbitrary number that may have a large standard deviation across many different overhead athletes.

 

GIRD vs. Total Range of Motion

While an athlete, especially an overhead thrower such as a baseball player, presents with limitations that reflect Reinold’s definition, how important is this loss of motion from a clinician’s perspective?

Now, am I going to worry or be alarmed by a loss of internal rotation that the athlete has with pitching over the course of the season? I suppose I may be in the event that the loss of internal rotation is not equally gained into external rotation, as the total range of motion would be negatively affected.

I’ve been taught that if the athlete has the same total motion throughout their full shoulder range with variations in internal and external rotation, then we can leave it without true intervention and move on, certainly if the athlete is asymptomatic.

On the flip side, if the athlete has lost internal rotation without a reciprocal gain of shoulder external rotation, I will certainly investigate why that may be. These limitations could be due to soft tissue limitations, bony changes into humeral retroversion, or capsular restrictions.

In particular with humeral bony retroversion, it’s critical to understand why this change exists. As young children play baseball, they compete with their respective growth plates in their humerus “open.” This is so that proper natural growth can occur, and that the bones will become longer as time progresses.

While these growth plates are open, throwing a baseball is a constant throughout the year. This continual cocking back of the arm while throwing “rotates” the humerus upon the growth plate, creating a retroversion moment of the bone over time.

This retroversion moment has even been described as “wringing out a towel” by Reinold, to explain the forces that are occurring at the humerus.

Ultimately, once the growth plates close, the retroversion is essentially sustained in that position that was allowed by throwing consistently over several years.

Because of this, baseball players have a natural, expected increase in external rotation within their dominant throwing arm compared to their other, non-dominant arm, that did not throw over the course of a childhood.

This physiological concept is a way to digest and understand the relative differences between arms in a baseball player, including the change in external rotation in the dominant arm being normal and expected anatomical variation.

 

What About Loss of External Rotation or Shoulder Flexion?

So we’ve established what GIRD is, how it can impact athletes, and the importance of both total and internal rotation shoulder range of motion. If shoulder internal rotation isn’t as important on its own, what other measurements can be performed to predict injury risk in a baseball player?

A recent article by Christopher Camp was published in September 2017 by Arthroscopy that highlighted other clinical measurements that may be greater predictors of injury than shoulder internal rotation.

The study followed one MLB team during a 6-year period and measured 81 pitchers over the course of the team’s annual physical examinations during Spring Training.

All elbow and shoulder range of motions were measured for each athlete, with a complete follow-up throughout the season to track any subsequent injuries with both days missed (DM) and re-injury status among other information recorded.

The article concluded meaningful information from the athletes over this time period that relates to the use of shoulder internal rotation measurements:

• The only independent variable that reported an increased risk of either shoulder or elbow injury was the presence of a shoulder ER 5° deficit (dominant arm external rotation was not at least 5° greater than non-dominant arm).
• Shoulder flexion deficits of 5° carried increased odds of sustaining an elbow injury.
• The presence of GIRD (defined as shoulder internal rotation deficit of greater than 20° compared to the non-dominant shoulder) did not carry an increased risk to the shoulder or elbow.


 

This study essentially found that within a large sample size of elite level baseball players, that there is decreased reliability on the use of GIRD to dictate whether a player is at increased risk of sustaining a shoulder or elbow injury.

The article also reports that the use of shoulder external rotation and flexion measurements may be more indicative of the risk of shoulder and elbow injuries, respectively.

Ultimately, I believe that as a profession we need to be able to look at solid clinical research such as this, utilizing a group of clinicians that actually treat baseball players, to make more effective conclusions about the health and status of the athletes we work with.

 

Final Thoughts on GIRD and Moving Forward

I believe in physical therapy and rehab in general, there’s a lot of buzzwords, hot topics, and just outdated information.

I think that GIRD is just one of the concepts that while important in the proper context, such as the loss of external rotation that occurs in conjunction with the loss of internal rotation (total range of motion loss), on itself does not hold as much merit as it receives in textbooks and other resources.

The article by Camp truly demonstrates that there are other factors to consider when attempting to understand a baseball player’s injury or their potential likelihood of injury.

It’s also important to note that these clinicians did not need to use diagnostic ultrasound or other fancy systems or equipment to predict an injury, rather using their clinical judgment and embracing the basics to interpret the findings.

I’m certainly not dismissing the concept of GIRD, but I think it’s important to consider the other deficits that may be present before concluding an athlete is at increased risk for injury. Every baseball pitcher is unique in their own appearance, mechanics, and even measurements that can all be seen as healthy and asymptomatic.

Being able to be a communicator with the athletes we treat about their arm using sound evidence-based research and experience will not only allow the athlete to build their rapport and confidence in you as a clinician, but facilitate a relationship that allows you to prevent injuries and truly achieve our ultimate aforementioned goal more effectively: getting to the root of a problem before it causes injury.

Humeral Retroversion Occurs in Youth Baseball Players as Young as Fourth Grade

A recent research report out of Japan continues to add to the body of evidence regarding humeral retroversion in the dominant shoulder in baseball players.  Essentially, the upper arm in baseball players has boney adaptations that occur while throwing as a youth with open growth plates.  This allows for external rotation (layback) while throwing, and is also responsible for the shift in total rotational range of motion and subsequent loss of internal rotation.

While this has been known for some time, we continue to see that this happens at an early age.  The authors of this study note that this occurred in youth athletes as young as in the 4th grade.

This boney adaptation is a requirement for throwing later in lift, showing the importance of needing to throw as a youth as young fourth grade.

Differences in humeral retroversion in dominant and nondominant sides of young baseball players.

J Shoulder Elbow Surg. 2017 Jan 25. pii: S1058-2746(16)30624-3. doi: 10.1016/j.jse.2016.11.051.

Kurokawa D1, Yamamoto N2, Ishikawa H3, Nagamoto H4, Takahashi H5, Muraki T4, Tanaka M6, Sato K6, Itoi E7.

Author information

  • 1Department of Sports Medicine and Orthopaedic Surgery, Tohoku Rosai Hospital, Sendai, Japan; Department of Orthopaedic Surgery, Tohoku University School of Medicine, Sendai, Japan.
  • 2Department of Orthopaedic Surgery, Tohoku University School of Medicine, Sendai, Japan.
  • 3Department of Physical Medicine and Rehabilitation, Tohoku University School of Medicine, Sendai, Japan.
  • 4Department of Orthopaedic Surgery, Kurihara Central Hospital, Kurihara, Miyagi, Japan.
  • 5Department of Orthopaedic Surgery, Kesen-numa City Hospital, Kesen-numa, Miyagi, Japan.
  • 6Department of Sports Medicine and Orthopaedic Surgery, Tohoku Rosai Hospital, Sendai, Japan.
  • 7Department of Orthopaedic Surgery, Tohoku University School of Medicine, Sendai, Japan. Electronic address: [email protected]

Abstract

BACKGROUND:

The relationship between the disabled throwing shoulder and humeral retroversion has recently attracted a great deal of attention. However, none of the previous studies clarified when the side-to-side difference of humeral retroversion in young baseball players would start. This study aimed to clarify when the difference of humeral retroversion in the dominant and nondominant sides appeared in baseball players.

METHODS:

The bicipital-forearm angle in bilateral shoulders of 172 elementary school baseball players was measured by ultrasound. The bicipital-forearm angle was defined as an angle between the perpendicular line to the bicipital groove and the ulnar long axis with the elbow flexed at 90°. The correlation between the bicipital-forearm angle and the grade and the difference of the bicipital-forearm angle between the dominant and nondominant sides were analyzed.

RESULTS:

In the nondominant shoulders, the bicipital-forearm angle increased with the grade in school (r = 0.32, P < .0001), but this was not observed in the dominant shoulders. In the fourth to sixth graders, the bicipital-forearm angles were significantly smaller in the dominant shoulders than in the nondominant shoulders.

CONCLUSION:

Our findings indicated that humeral retroversion decreased with age in the nonthrowing side but not in the throwing side and that the side-to-side difference of humeral retroversion in the baseball players became obvious from the fourth grade. We assume that the repetitive throwing motion restricts the physiologic humeral derotation process and the difference became apparent from the fourth grade when the growth spurt begins in boys.