Super Bowl XLIX Preview: Dislocation, Subluxation & Earl Thomas

Dr. Christopher Geary is Chief of Sports Medicine at Tufts Medical Center and the trusted resource for Inside The Pylon on injuries. Whether it is an ACL tear, a high-ankle sprain or an Achilles tendon rupture, Dr. Geary explains the gross anatomy and, in this installment, the general prognosis for shoulder injuries like the one sustained by Seattle Seahawks DB Earl Thomas.

Free safety Earl Thomas is one of the most important members of Seattle’s ferocious defense – his sideline-to-sideline athleticism and hard-hitting style frees other members of the secondary to play as aggressively as they do. So when he went down with a shoulder injury in the NFC Championship Game, the obvious questions were: What was the exact injury, and how would it impact his play if he did return?

Suffering the injury in the first half, Thomas returned to action during the second half, but questions remain about the nature of his injury and his status for the Super Bowl. Luckily, as the Mona Lisa Vito of orthopedics, I can shed some light on the situation.

Shoulder injuries can be confusing, especially given the terminology – the terms separation and dislocation are frequently used interchangeably in the media and by laypersons, but they apply to two different injuries in two different parts of the shoulder.

When orthopedic surgeons refer to a “separation”, we are usually referring to the acromioclavicular (AC) joint, the small joint on top of the shoulder at the end of clavicle:
normal_acjoint

This joint is frequently injured in contact sports, usually by a fall directly onto the shoulder. Oregon QB Marcus Mariota sustained this injury when tackled by Ohio State defensive end Joey Bosa in the college football championship game. Mariota missed some time but returned later in the game. This was also the injury which Emmitt Smith famously endured while racking up 168 yards against the Giants in 1993.

Impairment to this joint range from simple sprains to severe injuries involving a complete disruption of the ligaments, which can result in persistent pain and inability to return to normal activities without surgery. The vast majority of these injuries will not require surgery – even injuries more severe than simple sprains will usually resolve with time and short-term activity modification. Less severe injuries (sprains, or grade 1 separations) can usually be managed with training room treatments and, sometimes, game-time cortisone injections into the joint.

Thomas seems to have suffered what can more accurately be termed a dislocation of the shoulder (glenohumeral) joint itself. According to reports, the shoulder had to be reduced (popped back in) on the field. He missed four plays and returned with a brace on his shoulder. He has since missed some practice time, being listed as limited in practice. He has, however, insisted that he will play.

On Saturday, Seahawks head coach Pete Carroll went so far as to say, “It’s over. It’s over, really. It was two days of him being very uncomfortable with the setting and it’s over now. He was back in action and in full flow today”.

Now, with all due respect to how pumped and jacked Pete might be about the status of Thomas’s shoulder, I have no doubt that his free safety has not fully recovered in such a short time frame.

When someone Thomas’s age dislocates his shoulder ‒ even for as brief a period of time as Thomas did ‒ there is almost inevitably some tearing of the labrum of the shoulder. This can take place with a subluxation, or partial dislocation, but is almost universal when a full dislocation has occurred. The labrum is the ring of cartilage around the socket (glenoid) of the shoulder joint which normally acts to help to keep the ball (humeral head) stable in the socket.

A normally-functioning labrum is important because the shoulder is an inherently unstable joint – its socket is quite shallow, which allows for a great range of motion, but predisposes it to instability or dislocation. The labrum is one of several soft-tissue structures that can be injured in a shoulder dislocation, and is probably the single most important in terms of normal shoulder function. Once the labrum has torn, it rarely heals back in normal position, predisposing the athlete to recurrent dislocations.

In fact, a number of large studies have shown re-dislocation rates as high as 75% in young contact-sport athletes. The chance of recurrent instability is so high in this patient population that surgery is almost always the treatment of choice, whereby the labrum and other damaged structures are repaired either with open surgery or, more commonly, arthroscopically.

The return-to-play rate post-surgery for shoulder dislocations is quite high ‒ one recent study looked specifically at NFL players who had undergone surgery to address shoulder instability. Of the 60 who underwent surgery, 54 (90%) returned to play in at least one game. The average time between surgery and the first game back, however, was 8.6 months.

Another look comes from a recent multi-center study published in the American Journal of Sports Medicine, which examined the in-season return to play among athletes who had dislocated their shoulders. The authors found that 73% of these players were able to return to action that same season – missing an average of only 5 days of practice or competition before returning. Of those who did return, however, 63% had at least one more episode of instability that same season.

What does all of this mean for Earl Thomas and the Seattle secondary? I have very little doubt that Earl Thomas will play in the Super Bowl – the question is: How confident will he be in his shoulder to hold up to the rigors of taking down a rampaging Gronk? Only he can know the answer to that question, but there is no doubt that he is at a statistically higher chance of dislocating his shoulder again during the game than he would be if he had never injured it.

If he were to fall on it in just the right fashion again or have it wrenched awkwardly during a tackle, his left shoulder is certainly at higher risk of re-injury than his other shoulder. In the final analysis, I’d be surprised if he doesn’t have surgery on the shoulder in the off-season, but, for sixty minutes in Glendale, it just might hold up.

Follow us on Twitter @ITPylon.

Inside The Pylon covers the NFL and college football, reviewing the film, breaking downmatchups, and looking at the issues, on and off the field.

One thought on “Super Bowl XLIX Preview: Dislocation, Subluxation & Earl Thomas

Leave a Reply

Your email address will not be published.