Zack Wheeler is the most recent in a long line of pitchers to undergo Tommy John surgery. His particular surgery included repairing his ulnar collateral ligament (UCL) as well as his pronator teres tendon (PT, commonly known as the flexor pronator tendon). This primer explains the nature of Wheeler's injury and the steps needed to recover from it.
What is the UCL?
The UCL is a major ligament in the elbow that helps stabilize the elbow’s bones, and is especially important to throwing. It connects from the end of the humerus (the bone above the elbow joint) to the ulna (the inner bone of the forearm).
What is the PT?
The PT is a muscle located on the inside of the elbow that is responsible for pronating the forearm (turning the palm face down) and helps flex the elbow. Similar to the UCL, it connects from the end of the humerus and beginning of the ulna and goes to the middle of the radius (the other bone in the forearm).
How does a UCL get torn?
The UCL can get torn through repetitive motions causing excess stress on the elbow. When pitching, the elbow experiences tremendous stress; how fast the elbow extends directly corresponds (among other variables) to how fast the ball is thrown. In the case of Wheeler—and other pitchers who underwent Tommy John surgery—his UCL was unable to keep up with how fast he was throwing the ball for the amount and frequency at which he was pitching. It was reported that Wheeler had a lot of elbow pain last year, and that could certainly have contributed to his tearing his UCL. The pain might have caused his body to compensate by placing additional stress on other parts of his arm to allow him to still make his pitches and be effective. This is not to say that the Mets mishandled Wheeler last season; rather, the pitcher’s torn UCL was probably the byproduct of a separate injury to which his body responded.
While we're on the topic, it is worth mentioning that Mets GM Sandy Alderson acknowledged that Wheeler’s UCL was bound to tear and thus the organization allowed him to keep pitching last year until it had completely torn. Whether or not that was the right move is a conversation for another day, as I'm sure many people have different views. This article is solely meant to describe Wheeler's injury and the road to recovery.
What does the recovery look like?
The typical road to recovery for Tommy John surgery is about 8-12 months. However, the Mets stated that Wheeler’s recovery will be around 14 months and aim to have him in the majors by June 1, 2016. The Mets are clearly being conservative with Wheeler’s timetable, knowing that they have the benefit of a full season and offseason during which the right-hander can recover. The Mets will probably have Wheeler start next season in the minors to ease him into throwing against live hitters, and increase his workload until he is ready to join the major league team.
Since the surgery also included a repair of the PT tendon, it may increase recovery time slightly since more tissues are healing, which can cause an increase in inflammation and swelling. Everyone heals differently so it's tough to predict just how much longer the recovery time will be, but it would not be surprising if it adds another 2-4 weeks to Wheeler's initial recovery.
Early aspects of recovery include slowly restoring the range of motion in the pitcher’s elbow and reducing any inflammation, swelling, and irritation from the surgery. While it may sound simple, anyone who has undergone surgery can attest to the fact that this process is very slow and painful. Physical therapists will gently stretch the joint and massage the muscle to help increase the range of motion. The player will likely also wear a brace to help him move his elbow within a pain-free range, and to reduce any chance of a muscle contracture (essentially when the muscle becomes very stiff and inhibits how far the person can flex or extend the elbow).
The next stage of recovery begins once full mobility is restored and all of the inflammation, swelling, and irritation has settled down. This is when the player begins strengthening all of the muscles around the elbow and shoulder that have become weak from the surgery and from disuse. To these players, a one-or-two pound weight has never been so hard to lift. This phase must be handled very cautiously as the ligament is still prone to re-injury, which can cause a setback. Every person is different, so there are no strict guidelines dictating when a person will move from one phase to another. But, generally, physical therapists hope to restore full range of motion and strength by four months.
At this point, the pitcher is ready to start baseball-related activities, such as long-tossing; but he isn’t ready to pitch just yet. Instead, he will initiate a comprehensive interval throwing program, which has been proven to help pitchers regain their form. The pitcher will start tossing on flat surfaces and progress to farther distances and faster velocities. Eventually, he will throw off a mound for a set number of pitches, and will only throw fastballs before moving onto other pitches and breaking balls. Like the last phase, this process must be handled very cautiously, as the introduction of stress onto the surgically repaired elbow can cause setbacks and increase the risk of further injury. One extremely important aspect of phase is to prevent the pitcher from overthrowing the baseball, which they are probably very anxious to do (see Matt Harvey) after not throwing a ball for so long.
Overall, Tommy John is a very popular and effective surgery. One just needs to be careful throughout the entire process to avoid setbacks and ensure full recovery.