Fantasy Baseball Injury Report: Thumbs Down

Fantasy Baseball Injury Report: Thumbs Down

This article is part of our Fantasy Baseball Injury Report series.

It's a big thumbs down for MLB injuries this week with two All-Stars set to miss considerable amounts of time with thumb injuries. However, the injuries for Kansas City's Salvador Perez and Philadelphia's Bryce Harper involve two different types of tissues in what is a surprisingly unique joint of the body.

The thumb comprises three bones, the two phalanges and the first metacarpal of the hand. This is different from the other four digits as each finger as three phalanges. However, the corresponding metacarpals of each finger aren't very mobile. In the thumb, the first metacarpal articulates with one of the carpal bones of the wrist, forming the carpometacarpal (CMC) joint. The CMC joint is saddle-shaped, allowing for a high degree of motion. Moving distally (away from the wrist toward the tip of the thumb), the proximal phalanx joins with the first metacarpal, forming the metacarpophalangeal (MCP) joint. The MCP of the thumb is strengthened by two stabilizing ligaments, the ulnar collateral ligament (UCL) and the radial collateral ligament (RCL). The UCL of the thumb is the primary stabilizer and sits near the webbing of the hand and second (pointer) finger. The RCL sits on the opposite side of the thumb, closer to the wrist. The two ligaments stabilize the thumb when the pinching motion is performed or when attempting to grip an object.

Perez's injury involves the UCL ligament. The Royals catcher initially injured the thumb in May but returned to action after a brief IL stint. He aggravated

It's a big thumbs down for MLB injuries this week with two All-Stars set to miss considerable amounts of time with thumb injuries. However, the injuries for Kansas City's Salvador Perez and Philadelphia's Bryce Harper involve two different types of tissues in what is a surprisingly unique joint of the body.

The thumb comprises three bones, the two phalanges and the first metacarpal of the hand. This is different from the other four digits as each finger as three phalanges. However, the corresponding metacarpals of each finger aren't very mobile. In the thumb, the first metacarpal articulates with one of the carpal bones of the wrist, forming the carpometacarpal (CMC) joint. The CMC joint is saddle-shaped, allowing for a high degree of motion. Moving distally (away from the wrist toward the tip of the thumb), the proximal phalanx joins with the first metacarpal, forming the metacarpophalangeal (MCP) joint. The MCP of the thumb is strengthened by two stabilizing ligaments, the ulnar collateral ligament (UCL) and the radial collateral ligament (RCL). The UCL of the thumb is the primary stabilizer and sits near the webbing of the hand and second (pointer) finger. The RCL sits on the opposite side of the thumb, closer to the wrist. The two ligaments stabilize the thumb when the pinching motion is performed or when attempting to grip an object.

Perez's injury involves the UCL ligament. The Royals catcher initially injured the thumb in May but returned to action after a brief IL stint. He aggravated the injury early last week, and further testing revealed a full tear of the ligament. Perez underwent surgery to repair the damage and is expected to miss eight weeks. 

UCL tears of the thumbs have become somewhat commonplace in baseball with players like Mike Trout, Carlos Correa and, oddly enough, Harper all undergoing surgery to repair tears at the thumb. Looking at these previous examples, the Royals' eight-week estimate seems fair, and Perez should be back sometime in August. The team may opt to bring him back in a designated hitter role to prevent exposing the thumb to further setbacks while playing catcher.

Harper's injury did not involve any ligaments, but the underlying bone tissue was fractured when he was struck on the hand by a stray Blake Snell fastball. The exact bone broken remains unclear, but it sounds like surgery is a real possibility. Surgical intervention for fractures is usually needed if the bone has poor blood supply or the fragments of the bone have displaced. The latter seems more likely for Harper, and he is expected to face a timeline like Perez. Look for him to miss roughly eight weeks with a late August return possible. However, Philadelphia's place in the standings could influence a potential return. Either way it's a big loss for those invested in Harper.

Ronald Acuna

The Braves sluggers is currently sidelined with a foot injury after fouling a ball of his left foot. Initial X-rays failed to uncover a fracture, though the lingering soreness has left Acuna unable to put much weight on or through the foot. The injury could still be a bone-related issue, most likely a bone contusion. These types of injuries still heal like fractures with specialized bone cells laying down new bone tissue to repair the resulting damage. Time is needed for this to adequately occur, and an IL stint seems plausible. Look for Acuna to sit out a few more days to see if the foot improves before a final decision is made.

Check Swings

Mookie BettsLast week I warned that precedent suggested Betts would need longer than two weeks to allow his broken ribs to heal. Now the Dodgers are saying that do not anticipate Betts returning when that initial two-week window ends. While there hasn't been a setback, Betts still will likely need another week or two to adequately heal. He may then require a rehab assignment or ramp up period before he returns to the field. Stay patient here and hope his fractures continue to mend smoothly.

Aroldis Chapman: The Yankees reliever is scheduled to make a final rehab appearance for Triple-A Scranton/Wilkes-Barre on Tuesday as he works his way back from Achilles tendinitis. Chapman will return with an elevated degree of risk but hopefully the cause of the tendinitis flare up has been addressed and he is able to avoid a recurrence. The role in which Chapman will be utilized upon his return seems unclear for now. Manager Aaron Boone suggested Clay Holmes has earned the right to remain the closer for now with Chapman likely to slot in as a setup man.

Jazz Chisholm: The Marlins speedster has not played in Miami's last two outings after prematurely exiting Friday's contest with back spasms. Spasms are usually the sign of an underlying injury, most often a strain, and treating the symptoms as well as the root of the problem is key to returning to play. Hopefully the injury resolves itself with rest and treatment and Chisholm is back soon. Jon Berti will continue to start at second base as long as Chisholm is sidelined.

Jack Flaherty: The Cardinals right-hander was removed from Sunday's start against the Cubs due to stiffness in his right shoulder. The term "dead arm" was initially used to describe the issue though it was later described as a shoulder strain. Unfortunately, this is the same shoulder that forced Flaherty to start the year on the 60-day IL with inflammation. He has previously received a PRP injection on the area and will miss time with yet another injury. Fantasy managers should prepare for this to take longer than the minimal amount of time.

Manny Machado: The Padres infielder still has not played since suffering a gruesome looking ankle sprain on June 19. The injury has been diagnosed as a sprain and San Diego opted not to place him on the IL. The team has a scheduled off day on Monday, giving Machado another day to rest the area. If he cannot return on Tuesday, a retroactive move to the IL may be utilized.

Anthony Rizzo: The Yankees first baseman was struck by a pitch on the elbow in Monday's win over Oakland. The injury was deemed a contusion and it seems like Rizzo will be back in action on Tuesday. 

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ABOUT THE AUTHOR
Jeff Stotts
Jeff Stotts works as a Certified Athletic Trainer (MAT, ATC, PES, CES). He won the 2011 Best Fantasy Football Article in Print from the Fantasy Sports Trade Association.
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