Finally, a sunny day is in the forecast with pristine conditions. You make the trek out to work your bouldering project: the one involving a lot of funky pinch grips and thumb catches. After attempting this problem for several weeks, you link together the crux and come out on top!
You’re elated; however on the ride back home, you notice wrist pain at the base of your thumb. After giving it some thought, you realize this area has actually been nagging you for a while, but now it is impossible to ignore. That evening, you try to unwind by playing video games and texting with your friends, reminiscing on the great day. You head back to your 9-5 job for the week, waiting for your symptoms to improve, but it only seems to be getting worse. What could be going on?
This climber is likely experiencing a condition known as De Quervain’s Tenosynovitis. De Quervain’s is typically caused by overuse or an increase in repetitive activity, characterized by pain and tenderness at the base of the thumb. Within this region lies two tendons: the extensor pollicis brevis (EPB) and abductor pollicis longus (APL), which act to extend and abduct the thumb, respectively.
The tendon sheath produces synovial fluid, which acts to reduce frictional forces on the tendons during everyday actions involving the thumb. With this condition, repetitive gliding of these tendons can create shearing forces and subsequent microtrauma (9). The tendons and their sheath lie underneath the extensor retinaculum: a fibrous band of tissue that holds the tendons of the extensor muscles in place. Thickening of the extensor retinaculum has been associated with De Quervain’s (2,3,9), and in severe cases, extensor retinaculum thickening has been shown to be three to four times greater than normal (5).
Activities that involve forceful grasping with ulnar deviation or awkward wrist positions may predispose or exacerbate the issue (2,4,9). Some individuals exhibit anatomical variations in this region of the wrist, which may also be a factor in developing De Quervain’s (7).