<unk> , or<unk>  thumb, is a type of stenosing tenosynovitis in which the sheath around a tendon in a thumb or<unk>  becomes swollen, or a nodule forms on the tendon. In either case, the tendon can no longer slide freely through its sheath.  Affected digits may become painful to straighten once bent, and may make a soft crackling sound when moved.  More than one<unk>  may be affected at a time, though it usually affects the thumb, middle, or ring<unk> .  The<unk> ing is usually more pronounced in the morning, or while gripping an object firmly.
It is called<unk>  because when the<unk>  unlocks, it pops back suddenly, as if releasing a<unk>  on a gun. Risk factors for<unk>  include diabetes, gonococcal arthritis, swelling of the hand, work injuries involving prolonged grip or vibration, fractures of the hand and other circulatory problems.
The best way to prevent this problem from getting worse is to avoid<unk> ing the<unk> , which in turn leads to more swelling and more<unk> ing.
Trigger finger
Hammer toe
Rocker bottom foot
Club foot
Bowlegs
Webbed toes
Freckle
Brachydactyly