There wasn’t much positive for Philadelphia Phillies fans in the news about Zack Wheeler’s surgery. The star pitcher is scheduled to undergo thoracic outlet decompression surgery soon, and it’s important to understand what he’s up against.
Wheeler has been diagnosed with venous thoracic outlet syndrome (vTOS), a serious condition, though not as devastating as the neurogenic form (nTOS) that has derailed many pitchers’ careers. According to MLB.com’s Paul Casella, the venous version generally comes with a more favorable long-term outlook.
This update followed Wheeler’s earlier procedure to remove a blood clot near his right shoulder, and it officially ends his 2025 season. After consulting with multiple specialists, doctors determined that decompression surgery was necessary. The operation involves removing a rib to ease pressure on the subclavian vein, which transports blood from the arm to the heart, per the Cleveland Clinic.
One recent example of a pitcher who underwent the same procedure Wheeler is facing is Merrill Kelly, who had the surgery in September 2020 and came back the following year to make 27 starts, according to Casella. On the other hand, Washington Nationals star Stephen Strasburg is perhaps the most notable case tied to thoracic outlet surgery for the neurogenic form of the condition — fortunately not the type affecting Wheeler. Strasburg’s outcome is well known, and it serves as a cautionary tale.
Wheeler is expected to miss 6–8 months while recovering. Looking ahead, there was at least some optimism shared over the weekend from the Phillies’ medical staff.
Head athletic trainer Paul Buchheit noted that Wheeler’s situation was more of an acute problem rather than something long-standing, which should work in his favor during recovery, according to Casella.
President of baseball operations Dave Dombrowski also struck an encouraging tone, telling The Athletic’s Matt Gelb that the team expects Wheeler to return within that six-to-eight month window and perform at the same level fans are used to — barring any unexpected setbacks.
For now, the priority is Wheeler’s health and well-being, both for himself and his family. Once that’s achieved, Phillies fans will be eagerly waiting to see him back on the mound, doing what he does best: shutting down opposing lineups.