Rotatores muscles

The Rotatores (Rotatores spinae) lie beneath the Multifidus and are found only in the thoracic region; they are eleven in number on either side.

Each muscle is small and somewhat quadrilateral in form; it arises from the upper and back part of the transverse process, and is inserted into the lower border and lateral surface of the lamina of the vertebra above, the fibers extending as far as the root of the spinous process.

The first is found between the first and second thoracic vertebræ; the last, between the eleventh and twelfth.

Sometimes the number of these muscles is diminished by the absence of one or more from the upper or lower end.