Give yourself a thumbs-up and take a look: does the tip of your thumb bend backward at an unusual angle, maybe even 50 degrees or more? If so, you might have what’s commonly known as hitchhiker’s thumb, a trait also called distal hyperextensibility. While it might look like a fun party trick, doctors say there could be more to it.
According to Dr. Isabel Huang, a physical medicine specialist at UT Southwestern, this extreme flexibility is usually harmless. “In most people, it’s just a quirky thumb joint,” she says. However, for others, it may be a clue to a broader condition, like hypermobility spectrum disorder or even hypermobile Ehlers-Danlos syndrome (hEDS)—a connective tissue disorder that affects the entire body.
Dr. Raj Dasgupta, an internal medicine specialist in California, adds that hitchhiker’s thumb can also be genetic and often appears alongside other flexible joints. Though not dangerous in itself, excessive joint mobility can sometimes lead to early arthritis, grip problems, or joint instability, especially with age.
While the condition is understudied, one survey found that around 1 in 3 people may have it. Historically, studies show it occurs across all ethnic groups, with varying frequency.
Though hitchhiker’s thumb rarely requires treatment, those who experience discomfort can benefit from strengthening exercises, taping, or ergonomic adjustments to reduce strain. And if it shows up later in life, doctors recommend checking for signs of arthritis or other underlying issues.
If your bendy thumb isn’t bothering you, there’s no need to worry. But if it comes with other symptoms—like joint pain, fatigue, or digestive issues—it may be worth a chat with your doctor.
