What is a Double Thumb?
A double thumb, also known as thumb duplication, pre-axial polydactyly, or bifid thumb, is a congenital condition where a baby is born with two thumbs on one hand. This is a relatively common congenital hand condition. The extra thumb can be completely separate or appear fused to the normal thumb. It's typically not painful and usually affects only one hand.
The appearance of a double thumb can vary:
- Separate Thumbs: Two distinct thumbs may be present, each potentially fully formed or partially developed.
- Fused Thumbs: The two thumbs might appear joined or webbed together, sharing some tissues.
The condition is considered a form of polydactyly, meaning the presence of more than the usual number of fingers or toes.
Causes and Treatment
Thumb duplication is a congenital condition, meaning it's present at birth. The exact cause isn't always known, but it's believed to be related to genetic factors. Treatment options, if needed, are usually surgical and may include removing the extra thumb or correcting its positioning. The Boston Children's Hospital and Children's Hospital of Philadelphia offer more information on diagnosis and treatment.
Other Uses of "Double Thumb"
The term "double thumb" is also used in other contexts, unrelated to the medical condition:
- Double-Thumb Slap Technique (Music): In bass playing, this refers to a specific technique using both thumbs to create a slapping sound. See TalkingBass for details.
- 2Thumb Putter Grips (Golf): This is a brand name for putter grips that utilize a specific grip style using both thumbs. See 2Thumb Grip.
- Double Tap (Technology): In some contexts, like Apple Watch, a "double thumb" can refer to a double-tap action with the index finger and thumb, used as a gesture control (see Apple Support).
