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Covering sports injuries from the perspective of a certified athletic trainer and backed by analytics.

Understanding Anfernee Simon’s Thumb Injury

The first major injury of the regular season has occurred in the NBA after Portland Trailblazers guard Anfernee Simons suffered a thumb injury in the team’s season opener. The injury appeared on early injury reports as a thumb sprain but further testing revealed the severity of the ligament damage.

An MRI performed Thursday revealed Simons tore the ulnar collateral ligament (UCL) in his right thumb, an injury covered multiple times on InStreetClothes.com after players like Chris Paul and Bam Adebayo suffered comparable injuries.

To recap, the thumb is made up of three bones, the first metacarpal of the hand and the two phalanges. The proximal phalanx and first metacarpal form the metacarpophalangeal (MCP) joint at the base of the thumb. The MCP joint is stabilized by two ligaments, the UCL and the radial collateral ligament (RCL). Together the ligaments limit excessive motion, particularly with gripping or pinching. The UCL is the primary stabilizer of the thumb and is located near the webbing of the thumb and pointer finger.

The UCL is commonly sprained in professional sports often after a player gets the digit stuck on something like a base in baseball or caught in an opponent’s jersey. MLB players including Mike Trout, Carlos Correa, and Bryce Harper have torn their UCL while former NFL quarterbacks Drew Brees and Jay Cutler have endured the injury. The list of NBA players to undergo surgery to repair a torn UCL is quite extensive and includes current players like Paul, Adebayo, Marcus Smart, and Dennis Schroder, as well as retired players like Shaquille O’Neal and Joakim Noah.

Thankfully surgery has a very success rate and studies show rarely result in a dip in performance. According to the InStreetClothes.com/SMART database the average number of missed games for in-season UCL repairs in the NBA is roughly 22 games with the average number of days lost being 53 days (~7.5 weeks). These numbers would have Simons out longer than the early estimated timeline of four-to-six weeks. However, the players who returned the fastest were guards with similar demographics to the Portland guard, suggesting a quicker return may be plausible. Schroder was back the quickest returning after 37 days lost.

Surgery to fix a torn UCL has improved in recent years and could be a reason for quicker recovery timelines. In 2017, ESPN’s Stephania Bell detailed a UCL repair with internal brace augmentation after Trout suffered his injury. Simons is slated to undergo the surgery soon and will begin the rehab process almost immediately. His absence is a notable one for a Portland team searching for an identity in a post-Lillard world.