Inside Mike Trout's procedure, recovery process

ByStephania Bell ESPN logo
Thursday, June 8, 2017

Every year a handful of players succumb to a thumb, finger, hand or wrist injury sustained during a head-first slide; this year, it just so happens that the reigning AL MVP is among the victims.

Los Angeles Angels outfielder Mike Trout, regarded as perhaps the best player in baseball, is on the DL for the first time in his career after tearing the ulnar collateral ligament (UCL) in his left thumb. It is not only the Angels who are grieving, but all of Major League Baseball, as one of the most recognizable faces in the sport is forced to the sidelines for an extended absence.

But maybe Trout's absence won't be as long as everyone fears. And more importantly, maybe when he comes back, he'll pick up right where he left off.

On Wednesday, Trout underwent surgery with Dr. Steve Shin, director of hand surgery at the Kerlan Jobe Orthopedic Clinic in Los Angeles, to repair his damaged thumb ligament. The general goal of surgery with these injuries is simple: restore the normal anatomy and function of the UCL by repairing it to its bony attachment.

But, in Trout's case, there was another step involved.

According to the Los Angeles Times, general manager Billy Eppler confirmed that Trout underwent internal brace augmentation along with the UCL ligament repair and repair of the dorsal capsule. The capsule is soft tissue at the joint. It is often injured with these types of injuries, but it is easily repaired and does not affect the rehab or overall timetable.

In recent years, Shin has been pioneering a form of this particular surgical procedure that includes reinforcing the UCL repair with synthetic tape. The tape, SutureTape (made by Arthrex), is just over a millimeter in width, yet is incredibly strong. In this procedure, the surgeon anchors the tape over the ligament, essentially forming a bridge, and the procedure is referred to as a UCL repair with internal brace augmentation.

The surgeon drills one hole in the bone at the site of the ligament tear (most commonly at the base of the thumb) and another hole near the origination site of the ligament on the first metacarpal (the long bone of the hand that runs to the base of the thumb). Then, an anchor which holds the suture threads and one end of the tape is passed through the hole at the base of the thumb. This suture repairs the ligament back to the bone at its original attachment site, just like with a traditional repair.

The extra reinforcement comes with the placement of the tape over the ligament. A second anchor containing the tape tails is placed through the drill hole on the metacarpal, completing the internal brace construct. When the second anchor is being inserted, the thumb is positioned with a slight bend at the base to create the ideal tension in the internal brace. (It is critical for proper healing and functionality that the tape is not tighter than the native ligament.)

Why reinforce the ligament? After all, if the traditional repair has worked well enough to allow virtually all who have the procedure to return to their prior level of function, why create an additional step?

It would be easy enough to make a case for providing extra strength to support the ligament in its natural function of protecting the thumb simply by pointing out how often these injuries happen. If the ligament were strong enough to withstand the forces it is at risk of being subjected to, it wouldn't tear so often in the first place. In a recent laboratory study conducted by the Arthrex Research Department using cadaver specimens, the thumb UCL with internal brace was four times stronger than the standard repair with suture alone.

As encouraging as the extra-strength insurance of the internal brace repair may sound, the primary benefit of this additional reinforcement may not simply be in preventing re-injury. Given that the addition of the SutureTape immediately strengthens the repair, the athlete can begin moving his thumb much more quickly, mitigating some of the negative consequences typically seen with prolonged immobilization (stiffness, muscle atrophy) and helping with overall healing.

Translation? Shorter rehab time equals potentially a quicker return to play and, quite possibly, better performance at time of return to play.

One of the biggest pitfalls after a thumb, finger, wrist or hand injury to a power hitter -- besides the obvious consequences of the injury itself -- is the lack of power at the plate when the player does return. It has become expected that it will take a hitter time to ramp up to his previous level of play after injuring a body part responsible for controlling grip and bat swing. The loss of range of motion and strength that follows the immobilization normally associated with one of these injuries takes extended period to overcome. After weeks of rehab, a player may recover enough mobility and strength to execute baseball activities, but may still be lacking the ideal amount needed for his particular mechanics. Often the player returns to competition, usually in the form of rehab games to start, as a means of not only restoring timing and functional performance but also to further sport-specific strength and motion.

It is known in the medical world that earlier motion after injury or surgery will result in less stiffness of the tissue and decreased atrophy of the involved muscles. The sooner an athlete can begin restoring motion and strength, the more likely he is to regain both fully. And, the decrease in overall downtime means less time required to restore functional performance. For a hitter, that could translate to increased efficiency at the plate immediately after a return from injury.

Unfortunately, immobilization is often a necessary part of protecting the newly healing tissue after injury or surgery. With a UCL repair, too much movement too soon could damage the repair, defeating the purpose of the surgery. In the case of a standard repair, the thumb is typically placed in a cast for several weeks to allow the ligament time to sufficiently heal back to the bone. Even after the cast is removed, a protective device (such as a splint) is initially required as the athlete resumes activity.

In the case of the UCL repair with internal brace augmentation, the period of immobilization is merely a matter of days. The reinforcement offered by the tape is such that the athlete can begin range of motion activity within several days, performing strengthening and early baseball drills within a couple weeks and resumption of unrestricted baseball activities as early as four weeks, assuming all is progressing well. From that point, it becomes a matter of deciding when the athlete is ready to return to competition.

Looking for a comparison? Look no further than Trout's teammate, shortstop Andrelton Simmons, who underwent a similar procedure in May of 2016. Simmons underwent surgery, also performed by Shin, to repair a torn UCL in his left thumb (like Trout, Simmons injured his non-dominant thumb). He too had the internal brace augmentation. Simmons began swinging a bat, playing catch and fielding ground balls within two weeks post-surgery. At four weeks, he began a rehab assignment and at just over a month post-injury he rejoined his major league club.

Perhaps more noteworthy is how Simmons played when he returned. For starters, he had two hits in his first game back. Although the remainder of his first week appeared to be a bit of a struggle (three hits in 23 at-bats), Simmons went on to hit .315 for the remainder of the season. And, he missed only four more days in 2016 (one for rest, three because of a contusion on his opposite hand). He has had no issues with his thumb since his return.

While comparisons can be useful, it is important to remember that each athlete heals at his own pace based on his individual injury and recovery. The timing of a return can also be influenced by player position, seasonal calendar and the needs of a team. Given the variables, it would be wise not to try to project Trout's precise return date. The timetable offered by the Angels of six to eight weeks is certainly reasonable, and allows for the potential of any one of the above named factors to play a role. The best interest of their star player for the long term remains the primary goal of the club, and there is no need to rush him into action before he is convincingly ready to return.

Nonetheless, Trout has been such a remarkable player throughout his still-early baseball career that everyone wants to see him return and be, well, Mike Trout. Based on the combination of his athleticism, skill, work ethic and overall health -- with a little help from modern medicine -- it appears by the end of the 2017 season, Trout could very well make us forget he was ever sidelined.