Much has been made in recent weeks in regards to Cam Newton and his troublesome right shoulder, which forced him to be shut down early this season for the Carolina Panthers. Newton started out the season on fire, ranking as QB4 overall from Weeks 1-9 while posting some of the best numbers of his professional career. During that time frame, the Panthers appeared to be well on their way to a playoff birth, posting a 6-2 record. However, since Week 8 when Newton first popped up on the Panthers’ injury report with a right shoulder injury, Newton’s numbers began to fade along with Carolina’s record. For more details regarding Cam’s performance this season, check out the chart below.

Weeks 1-9 Weeks 10-15
Attempts 263 208
Completions 177 143
Completion Percentage 67.3% 68.8%
Yards/Game 236.6 250.3
Passing TD/Game 2.13 1.5
INT 4 9
Fantasy Ranking (Points/Game) QB4 QB21

As you can see, Newton’s fantasy production plummeted in the second half of the season largely due to an inability to find the end zone and his remarkably high turnover rate. Meanwhile, his completion percentage and passing yardage improved. Is there a medical reason behind this drastic shift in fantasy production? Let’s dive further into Newton’s shoulder to find out. As a sports and orthopedic physical therapist, I’ll try to keep this simple for the most part, but bear with me if I get too technical!

Newton’s Shoulder Surgery

You may or may not know that Cam Newton’s right shoulder has been an issue in the past. In fact, he had surgery to repair a torn rotator cuff in March of 2017. Now, the rehab for this type of surgery is pretty conservative, so it’s no surprise that Newton pushed the envelope in terms of being ready to go for Week 1 of the 2017 season. That’s not his fault; that’s the nature of the rehab associated with a rotator cuff tear. Ultimately, Newton was ready for Week 1, and he played in all 16 regular season games last year.

I’m not able to speak directly to Newton’s specific shoulder surgery because there are four different muscles that make up the rotator cuff (see below). I don’t know specifically which muscle(s) was involved or the size of the tear, both of which matter when you’re talking about a players rehab and timeline for recovery. Regardless, Cam played a full season without setbacks or limitation…until now.

The 2018 Season

The reason I bring up Cam’s 2017 surgery is that it could certainly be involved once again. I’m not saying it is involved, but there’s a chance it is, along with some other structures (more to come soon). In rehab and the medical world, a prior injury is the number one risk factor for future injury. That’s why guys who tear their ACL are more likely than another player who hasn’t torn their ACL to re-injure their knee. The same is true for rotator cuff tears, especially in overhead athletes like baseball pitchers, volleyball players, and yes, NFL quarterbacks.

Like I said earlier, Cam came out on fire! However, those flames started to turn to ice as the season progressed, particularly after Week 8 when Newtown first popped up on the injury report for the Panthers with his shoulder injury. Now, guys in the NFL pop up on the injury report every week, and as long as they play through the injury, it’s usually no big deal. However, Newton’s case is much different. Since popping up on the injury report in Week 8, Newton’s practice activity slowly started to decline. In fact, the last time he had multiple full practices in a week was Week 9. In every week since then, Newton’s practice activity dwindled in an effort to keep Newton active the week ahead. Veteran rest, or something more?

What’s wrong with Cam’s shoulder?

By now, you probably know the answer to my last question in the section above. This was not simply veteran rest. Rather, there was a larger issue at hand, something that eventually led to Newton being shut down after the team’s Week 15 loss to the Saints. After going back and watching Newton’s game tape from Week 11-15, I noticed something that is not uncommon for the shoulder of overhead athletes. It’s called glenohumeral internal rotation deficit, or GIRD. Basically, a throwing athlete’s shoulder adapts as time goes by to allow the shoulder joint (the glenohumeral joint) to be able to rotate at extreme amounts in order to allow the throwing motion to happen. A throwing athlete’s shoulder will almost always have a much greater degree of external rotation relative to internal rotation. It helps create torque and velocity so an NFL quarterback can zip it in between two defenders on a slant route or a major league pitcher can throw it 95 mph. It’s advantageous, and actually a good thing. However, it becomes an issue when this high degree of rotation is lost as the season goes by, creating an overuse type of injury. As the season goes by, and the shoulder is used over and over and over again while throwing, the back of the shoulder joint and the rotator cuff can get tight, leading to a loss of internal rotation range of motion, a.k.a GIRD.

How does GIRD affect an overhead athlete?

GIRD can create a whole host of issues for the health of a shoulder and in particular, the rotator cuff muscles. For a throwing athlete, the rotator cuff is everything. It helps to generate power, decelerate the arm, and stabilize the shoulder (ball and socket) joint during a very violent and extreme motion. So, whenever an athlete as a notable rotator cuff injury in their history (i.e. Cam Newton), it shouldn’t go unnoticed.

When I went back and watched Newton’s game tape, I began to notice a change in his delivery. At the start of the season, Newton’s throws had much more velocity, he was pushing the ball downfield more frequently, and he appeared to generate more power from his shoulder. However, in recent weeks, Cam struggled with his velocity, frequently throwing the ball in the dirt at his receiver’s feet. In addition, his throws looked more labored, as he was having to rely a lot more on his lower body and torso. This is largely because of the fact that Cam was starting to lose rotation in his shoulder, the troublesome GIRD that I’ve already discussed.

GIRD has been associated with numerous pathologic conditions, including labral tears and rotator cuff tears. For more details on a labral tear injury, check out my Andrew Luck article from the last off-season. When the shoulder loses rotational range of motion due to repetitive stress, the demand and strain on the shoulder joint, labrum, and rotator cuff go up…exponentially. With each throw or pitch after GIRD has developed, these tissues are loaded to levels that approach their ultimate load to failure, otherwise known as their injury threshold. In the vast majority of cases, these rotator cuff injuries are not acute and traumatic in nature. Rather, it’s the repetitive microtrauma (a.k.a. ‘wear and tear’) that takes place over the course of the season that leads to issues with the rotator cuff.

What is the treatment?

If this pathological change is caught early, physical therapy and rehab are effective for athletes to return to throwing without issues and without surgery. First and foremost, the athlete must stop throwing. A program will typically consist of stretching the rotator cuff and back of the shoulder joint, otherwise known as the capsule. The goal of the stretching program is to restore the full arc of shoulder rotation that the athlete once had at the start of the season. Once this is achieved, rotator cuff and shoulder blade strengthening are the mainstays of rehab followed by a graded return to throwing.  However, if a rotator cuff injury has already occurred, the athlete may require surgery to repair the torn muscle(s). If this is the case, a post-operative conservative rehab protocol must be followed, as was the case for Cam in 2017.

What’s next?

It’s impossible at this point to know exactly what is going on with Newton’s shoulder on a structural level. Is there a labral tear? A torn rotator cuff? Both? We just don’t know. If those injuries are present, trouble could lie ahead for Newton this off-season, and potentially, beyond. However, it’s also certainly plausible that the Panthers were being proactive with the face of their franchise by shutting him down early. Certainly, the medical staff was seeing the decline in Newton’s shoulder rotation and his performance on the field. Maybe they chose to address the loss of shoulder rotation before it becomes a bigger injury. At this point, there’s no way of knowing, and as fantasy football players, we’re going to have to wait and see. With Week 17 and the regular season coming to a close, I suspect we’ll hear more about Newton’s right shoulder heading into the team’s off-season conditioning program. I’ll plan to post an update to this article later on this off-season after more details emerge, but in the meantime, if you’re looking for more information about GIRD and how it affects throwing athletes, check out this research article.


Photographs found:
1. https://step2.medbullets.com/orthopedics/120532/rotator-cuff-injury

2. Wilk KE, Macrina LC, Fleisig GS, et al. Correlation of glenohumeral internal rotation deficit and total rotational motion to shoulder injuries in professional baseball pitchers. Am J Sports Med. 2011;39(2):329–335

3. Baseball pitcher: Braun S, Kokmeyer D, Millett PJ. Shoulder injuries in the throwing athlete. J Bone Joint Surg Am. 2009;91(4):966–978


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