Which category of anomalies includes extra bones such as additional carpals or metacarpals?

Which category of anomalies includes extra bones such as additional carpals or metacarpals?

• A. Accessory foramina
• B. Non-fusion anomalies
• C. Accessory bones
• D. Deformative

Answer: (C)

Extra bones in the hand, such as additional carpals or metacarpals, are described as accessory bones. These arise when additional ossification centers persist during development, producing a bone that sits alongside the normal skeletal elements rather than replacing them. This category is distinct from accessory foramina, which are extra openings; non-fusion anomalies, which involve incomplete joining of bones during growth; and deformative changes, which are alterations in shape from injury or disease. In short, extra, nonstandard skeletal elements are best classified as accessory bones.

Extra bones in the hand, such as additional carpals or metacarpals, are described as accessory bones. These arise when additional ossification centers persist during development, producing a bone that sits alongside the normal skeletal elements rather than replacing them. This category is distinct from accessory foramina, which are extra openings; non-fusion anomalies, which involve incomplete joining of bones during growth; and deformative changes, which are alterations in shape from injury or disease. In short, extra, nonstandard skeletal elements are best classified as accessory bones.