De Quervain's Tenosynovitis

De Quervain's tenosynovitis typically develops from repetitive thumb movements combined with ulnar deviation (bending your wrist toward your little finger). The classic movement pattern that triggers this condition is lifting or grasping with your thumb while simultaneously bending your wrist sideways. This combination creates maximum stress on the APL and EPB tendons as they pass through the narrow tunnel at your wrist.

New parent activities are a notorious trigger - repeatedly lifting a baby while supporting their head creates the perfect storm of thumb abduction and wrist deviation. The "baby lift" movement, where you scoop up an infant with your thumbs extended and wrists bent, places enormous strain on these tendons. Text messaging, smartphone use, and gaming can also contribute, especially when you use your thumb for extended periods while your wrist is in an awkward position.

Occupational activities involving repetitive pinching, gripping, or twisting while using your thumb are major contributors. Activities like hairdressing (using scissors), gardening (pruning with secateurs), or any job requiring sustained pinch grip with wrist deviation can gradually irritate the tendon sheath. Even seemingly minor activities like wringing out washcloths, opening jars, or using a computer mouse for extended periods can trigger symptoms if done repeatedly with poor wrist and thumb positioning. The condition is particularly common in women, possibly due to hormonal factors that affect tendon healing, combined with activities like childcare that involve repetitive thumb loading.