NBA Draft Injury Series: Justin Jackson’s Shoulder

By Dr. Ankur Verma

The NBA Combine just wrapped up in Chicago and while many of the prospects went through drills and scrimmaging, the most important part of the Combine remains the medicals.

In honor of that, we are looking at 2018 NBA Draft prospects with injury questions and trying to determine if we can glean anything about their future based on their respective injuries.

For analysis of Michael Porter Jr., click here.

For analysis of Bruce Brown, click here.

As always, we’re not privy to the specific medical information for these prospects; we’re just trying to draw conclusions based on available public information.

Today, we’ll take a look at the curious case of Justin Jackson.

Credit: Maryland GovPics

Justin Jackson, Forward, Maryland  Age-21  Height- 6’7”  Weight-229 lbs

 

A year ago, Jackson was a surprised early entrant in the NBA draft after his freshman season.  He proceeded to impress in predraft workouts and the NBA combine, displaying potential as a possible 3-and-D prospect (and maybe more) with his 7’3” wingspan and shooting ability (43.8% three-point shooting his freshman year).  However, he eventually withdrew from the draft when he couldn’t solidify his status as a sure first-round pick.

He was expected to blossom his sophomore year by playing more on the perimeter while new incomers handled the situation up front.  However, he struggled mightily as his three-point shooting tanked (25%) and his overall effective field goal percentage dropped from 52.4% to 41.6%, all while playing roughly the same amount of minutes per game.

In the beginning of December, Jackson then missed three straight games with what Maryland initially called a “sore shoulder”.  On December 28, it was announced that Jackson actually had a torn labrum and would miss the rest of the season.

There are a couple of interesting things to point out in that Washington Post article.  The first thing is Coach Mark Turgeon states that Jackson was dealing with the shoulder injury all season.  Could this explain Jackson’s steep decline?

Second, it’s worth noting that Turgeon first mentioned the sore shoulder a few days after Jackson played a heavy workload against Illinois in early December.  In that game, he played 41 minutes, surpassing his previous season-high of 37 minutes, and scored a season-high 20 points.  Jackson then went on to play just 19 minutes against Ohio the next game before being shut down for the season.

Okay, so it’s fair to wonder at this point that if Turgeon knew that Jackson had been dealing with a sore shoulder all season, then why did he let his star player take on such a heavy workload?  Objectively, the injury was, of course, bad enough that Jackson subsequently played a season-low in minutes, so one would think that if Turgeon knew the extent of the injury, he would have known that things might have been reaching a breaking point and would have monitored his player’s minutes accordingly.  Otherwise, the nature of events seems abrupt from the outside.

It’s even more curious when coupled with this third point, a quote from Turgeon in that article:

“It’s an old injury.  It happened before he came to Maryland, is what doctors told me.  He reaggravated it a lot this year…he tried to play through (the torn labrum) for his team.”

So it seems that this injury was known by a few people.  Of course, I have no way of knowing to what extent and how the Terrapins monitor workload and factor in injury prevention in their basketball program.

Glenoid Labrum, here labeled as Gelnoid Lig. (Credit: Gray’s Anatomy)

The labrum is a piece of cartilage that is attached to the glenoid, which is the “socket” part of the shoulder.  It provides some stability for the joint.  Labrum injuries are typically seen in baseball pitchers due to excessive traction on the labrum in throwing or overhead actions.

There are two type of labral injuries: SLAP and non-SLAP.  The superior part of the labrum serves as the attachment site for the biceps tendon, so tears that involve this portion are called SLAP lesions (superior labrum anterior to posterior).

An example of a non-SLAP tear is a Bankart lesion, which is an injury to the anterior (as opposed to superior) part of the labrum.

In any case, in an athletic population, these shoulder injuries are usually repaired by reattaching the labrum to the glenoid (or at the very least arthroscopic “clean-up”), whether SLAP or non-SLAP.  For outcomes after surgery, it certainly seems that the younger you are, the better the chance of a successful surgery according to studies.

So how does Jackson’s forefathers in the NBA fare after labrum tears?  Using my NBA injury database, plus ProSportsTransactions searches, this is a list of NBA players that were drafted since 1989 that suffered labral tears during their NBA career.  Since tears are much more uncommon in the NBA compared to other injuries, I expanded the list to include players that suffered the injury at any point in their careers, as opposed to just as their initial injuries (as I have done for other posts).  I only included players if they were not active during the 2017-18 season so that we can get a sense of their entire career arc.  Usual caveats apply.

NBA players with Shoulder Labrum Tears

NameAgeHeightWeight (lbs)MP%Recurrence?MP% x 2
Jim McIlvaine267-124020.9NoN/A
Kirk Hinrich316-419027.2NoN/A
Lamar Odom256-1022057.7Yes43.0
Eddie Jones296-619048.0NoN/A
Kobe Bryant246-621265.4NoN/A
Raef LaFrentz326-112400NoN/A
Toney Douglas246-219559.3NoN/A
MP%= Percentage of career minutes played AFTER the labrum tear
Recurrent= Subsequent labral injury that caused missed games
MP% x 2= Percentage of career minutes played after second labrum tear

 

Lamar Odom was the only player on this list to sustain a second labral injury.  This is important to find out because, as Turgeon said, Jackson’s injury seems to have lingered for a couple years; it is unclear whether he had surgery on it previously.  So we’re headed into a bit of uncharted territory here.

There isn’t a great physical comparison to Jackson on this list.  The closest is probably Kobe Bryant, though Jackson is a bit heavier.  In addition, Bryant had an arthroscopic surgery to repair a frayed labrum as opposed to a true tear like Jackson.

The good news is that if you look at the younger players on that list, they seem to go on to have relatively healthy careers, at least in terms of relative minutes played.  The exception is Jim McIlvaine, who tanked afterwards, but isn’t a positional or style match for Jackson, as well as Raef LaFrentz as the surgery seemed to end his career.  Admittedly, LaFrentz had more stretch to his game like Jackson, but isn’t exactly a match physically.

The shoulder undoubtedly plays a role in shooting mechanics, and since shooting is such a vital part to what makes Jackson attractive as an NBA prospect, let’s take a look at how these players fared shooting-wise after their injuries (Jim McIlvaine was excluded as he barely shot the ball).

Labral Tear Shooting

NameeFG% BeforeeFG% After3pt% Before3pt% AfterShooting Hand?
Kirk Hinrich48.446.538.036.1No
Lamar Odom47.551.330.931.5Yes
Eddie Jones51.349.637.736.9No
Kobe Bryant48.148.233.232.9Yes
Toney Douglas52.246.037.833.4Yes
eFG%= Effective Field Goal Percentage
Shooting Hand= whether labral tear was on the dominant shooting side
For Odom, I used his first shoulder injury as the demarcation for Before/After

 

There’s no real trend here.  What’s interesting is the two players who were injured in the non-shooting side experienced decline in shooting, though it’s hard to say if that’s significant.  Jackson was injured in his shooting shoulder, for what it’s worth.

Rehabilitation for a shoulder labrum tear usually involves physical therapy focusing on scapular stabilization and stretching the posterior capsule of the shoulder, as well as improving range of motion, proprioception, strength, and endurance.

Level of Worry: Jackson was certainly on the first round bubble before his shoulder injury and now, after it, he is falling squarely in the middle of the second round conversation.  He was not helped by a subpar sophomore season prior to the injury.  If he was truly hampered by a sore shoulder all year and it affected his play, then it doesn’t bode well at least for his immediate future, as he was unable to address the questions surrounding him as an NBA prospect and there are certainly signs that the injury is still lingering.  For instance, it takes about 4 to 6 months for a complete recovery, assuming reattachment or repair  was required, which places Jackson right in the range.  Thus it’s unfortunate that he declined to participate in drills or 5-on-5 scrimmages at the NBA Combine (though he was present for measurables).  Since we were unable to see him shoot, he is still largely an unknown quantity as The Ringer mentions that he needs to speed up his stroke, which implies his mechanics aren’t perfect—and that is even before factoring in the injury.  What’s more, there’s a report that he went home before Day 2 of the Combine because he was still experiencing lingering soreness.  And that’s without mentioning the chronicity of the injury as it seems to stem from his high school days.  Therefore, if I were an NBA front office, I would be moderately concerned about the injury given that we can’t even project what a truly healthy Jackson would look like, even if we can’t draw any trends from NBA history.

Thanks to Brukner and Khan’s Clinical Sports Medicine for information on labral tears.