Anatomical variation

An anatomical variation, anatomical variant, or anatomical variability is a presentation of body structure with

Variations are seen as normal in the sense that they are found consistently among different individuals, are mostly without symptoms, and are termed anatomical variations rather than abnormalities.[2]

Anatomical variations are mainly caused by

A very early paper published in 1898, presented anatomic variations to have a wide range and significance,[3] and before the use of X-ray technology, anatomic variations were mostly only found on cadaver studies. The use of imaging techniques have defined many such variations.^[4]

Some variations are found in different species such as polydactyly, having more than the usual number of digits.

Variants of structures

Muscles

Kopsch gave a detailed listing of muscle variations. These included the absence of muscles; muscles that were doubled; muscles that were divided into two or more parts; an increase or decrease in the origin or insertion of the muscle; and the joining to adjacent organs.^[2]

The palmaris longus muscle in the forearm is sometimes absent, as is the plantaris muscle in the leg.^[5]

The

The lungs are subject to anatomical variations.^[8]

Clinical significance

Accessory small bones called ossicles may be mistaken for avulsion fractures.^{[citation needed]}

See also

• Supernumerary body part
• Visible difference

References