What is polydactyly? Polydactyly is a deformity in which the hand has one or more extra fingers in any of three places of the hand: on the small finger side most common (ulnar) on the thumb side, also called thumb duplication less common (radial) in the middle of the hand least common (central) What are the different forms of polydactyly? skin and soft tissue the simplest to remove skin, soft tissue and bone but no joint more challenging to remove/remodel skin, soft tissue and bone with joint (closer to a fully-formed finger most challenging to remove/remodel) Is this is a hereditary problem? Yes but some time it present non hereditary. What causes polydactyly? During normal embryonic development (while the baby is still in the womb), the hand initially forms in the shape of a paddle, and then at about the sixth or seventh week of gestation splits into separate fingers. Polydactyly results if there's an irregularity in this process: An extra finger forms when a single finger splits in two. How is polydactyly diagnosed? Polydactyly can be seen by ultrasound prenatally, and after birth by clinical examination. How is polydactyly treated, and at what age? The extra finger can be removed surgically, when the child is between 1 and 2 years old, young enough that he won't miss developmental milestones such as grasping (prehension), but late enough that he can tolerate anesthesia and surgery well. What are the Complications of surgery? Major complications after surgery are rare but often minor like scar formation, stiffness, instability, and late deformity. Most cosmetic or functional deformities can be addressed in later corrective surgery. What is the outcome of polydactyly surgery? Most of the young patients have full hand function and an improved appearance of the hand. It is possible that in a severe case, may need additional reconstructive surgery to recover full function and improve the hand's appearance.