This article is part of our Fantasy Baseball Injury Report series.
Occasionally during a MLB season we see a sudden influx of one particular injury. One such case has emerged over the last few weeks, with multiple players succumbing to hamstring injuries.
Hamstring strains generally occur at a high frequency, but this recent stretch appears to be above the norm. The degree of damage has varied in some cases, making it difficult for fantasy owners to appropriately manage their rosters. Before we tackle some of the particulars with a hamstring injury, let's do a quick review of the details associated with any muscle-related injury.
A strain occurs when muscle tissue is stressed beyond its yield point. Strains can occur in the tendon or muscle belly of the involved muscle. Regardless of location, muscle strains receive a medical grade based on the severity of the associated damage. A Grade 1 strain is the lowest possible grade and is often referred to as a mild or minor injury. In these injuries, microtearing of the tissue has occurred though the individual displays little to no loss of function. A Grade 2 is considered more moderate and involves damage to actual muscle fibers. These injuries are often referred to as partial tears. Anything given a Grade 3 or higher is considered severe and the tear is often complete. Grade 3 injuries are accompanied by a loss of stability and function, and in some cases may require surgical intervention.
The body's natural response to a muscle injury is a complex, multistage process. The initial phase is
Occasionally during a MLB season we see a sudden influx of one particular injury. One such case has emerged over the last few weeks, with multiple players succumbing to hamstring injuries.
Hamstring strains generally occur at a high frequency, but this recent stretch appears to be above the norm. The degree of damage has varied in some cases, making it difficult for fantasy owners to appropriately manage their rosters. Before we tackle some of the particulars with a hamstring injury, let's do a quick review of the details associated with any muscle-related injury.
A strain occurs when muscle tissue is stressed beyond its yield point. Strains can occur in the tendon or muscle belly of the involved muscle. Regardless of location, muscle strains receive a medical grade based on the severity of the associated damage. A Grade 1 strain is the lowest possible grade and is often referred to as a mild or minor injury. In these injuries, microtearing of the tissue has occurred though the individual displays little to no loss of function. A Grade 2 is considered more moderate and involves damage to actual muscle fibers. These injuries are often referred to as partial tears. Anything given a Grade 3 or higher is considered severe and the tear is often complete. Grade 3 injuries are accompanied by a loss of stability and function, and in some cases may require surgical intervention.
The body's natural response to a muscle injury is a complex, multistage process. The initial phase is the inflammatory phase and is marked by the preliminary swelling and clotting reactions at the injury site. As the inflammatory phase progresses, the second phase, the proliferative phase, begins. The proliferative phase is the beginning of the body's true "repair work" of the damaged tissue. Scar tissue is formed at the injury site as specialized cells begin repairing the strain using various protein fibers, including collagen and elastin.
The proliferative phase requires a considerable amount of time but must be completed before the final phase, the remodeling phase, can begin. The remodeling phase varies in length and depends on the degree of damage. During this phase, new collagen-rich scar tissue is repeatedly broken down and remade. This process allows the strength of the scar tissue to gradually improve. Over time, the scar tissue will begin to resemble healthy muscle tissue. However, the body's natural way of healing often occurs in a disorganized manner with the new fibers unsystematically laid down. Unfortunately this haphazard method can have a negative impact on the athlete's recovery. Fortunately, a skilled medical professional can intervene and combat this approach during the rehab process.
Still, even the best treatment can't guarantee the new tissue will be as strong as the original, and the risk of re-injury will linger. This is particularly true in hamstring strains. The hamstring isn't an isolated muscle but instead a group of muscles. Together, the hamstring muscle are able to complete dynamic motions like running and jumping. Because of these high demands, the hamstring muscles are routinely subjected to high amounts of force. As a result, hamstring injuries generally require long periods of rest. A recent study placed the average time missed for hamstring strains in the MLB at roughly three weeks. Even worse, these injuries are often aggravated, forcing the individual to restart the aforementioned healing process.
Texas third baseman Adrian Beltre recently suffered a Grade I hamstring in a loss to Oakland. He has been placed on the 10-day DL, making this his fifth DL-stint with lower extremity-related problems since 2011. Beltre has previously missed time with hamstring and calf injuries. These previous injuries along with his advanced age make it very likely that Beltre misses more than the allotted 10 days. Fantasy owners shouldn't expect him back until mid-May.
White Sox outfielder Avisail Garcia is 13 years younger than Beltre but could be equally limited by his hamstring strain. Garcia suffered a right hamstring strain while trying to beat out a grounder, an injury manager Rick Renteria later described as "mild to moderate." It sounds like Garcia's injury may be closer to a Grade 2 type injury, setting him up for a multiweek absence.
The hamstring ailment that sidelined Boston's Mookie Betts over the weekend is currently being labeled as tightness. The decision to keep him off the field was described as purely precautionary but could put Betts owners in a tough spot for the week ahead.
It hasn't just been positional players enduring hamstring strains. Indians reliever Andrew Miller was recently placed on the 10-day DL after injuring his left hamstring during a win over the Cubs. Initially ruled hamstring tightness, the diagnosis was changed to a strain following a MRI.
Miller was able to play catch over the weekend, a good indicator that the strain is mild. As previously discussed following Corey Knebel's injury, the hamstring plays an important role in a pitcher's delivery. A premature return to the mound could prove costly for Miller, and it seems likely Cleveland takes a conservative approach with his recovery. He's eligible to return May 6 but I'm guessing this keeps him out a bit longer.
Check Swings
Byron Buxton: Buxton's return from migraines has been derailed by a toe injury sustained during a recent rehab game. The Minnesota outfielder fouled a ball of his left big toe. The damage to his toenail was significant and required a minor procedure to reduce the pressure. Additional testing revealed a hairline fracture in the underlying bone. He remains without a definitive timeline, but a three- to four-week absence seems probable.
Wil Myers: The Padres have placed Myers on the DL for the second time this season. Myers' latest injury is a left oblique strain that occurred during a failed swing. The recovery from an oblique strain is usually measured in weeks not days, and it seems likely this injury will keep him out longer than the nerve irritation he sustained earlier in the season.
Shohei Ohtani: A sprained ankle will push back Ohtani's next start but isn't significant enough to keep him from making plate appearances. The Angels rookie will serve as the team's DH when they begin their series with the Orioles. However, he won't pitch again until the upcoming weekend series against the Mariners.
Yasiel Puig: The Dodgers outfielder is headed to the DL with two injuries that occurred following a collision with the outfield wall. Puig sustained a hip pointer and a bruised foot upon impact and will spend the next 10 days recovering. Hip pointers can be extremely painful injuries, but the foot ailment appears to be of greater concern. Despite the designation, the Dodgers have downplayed the issue and appear optimistic about a quick return.
