The spinalis muscles are a group of muscles located in the back. They include the spinalis thoracis, spinalis cervicis, and spinalis capitis muscles. The spinalis thoracis is a small muscle located in the upper back, between the scapulae (shoulder blades). The spinalis cervicis is a small muscle located in the neck, between the occipital bone and the spinous processes of the cervical vertebrae. The spinalis capitis is a small muscle located in the back of the head, between the occipital bone and the spinous processes of the upper cervical vertebrae.

The main function of the spinalis muscles is to extend the vertebrae at the intervertebral joints. This movement is essential for activities such as looking upwards and arching the back, and helps to provide stability and support for the spine. The spinalis muscles also help to rotate the vertebrae, and assist in lateral flexion (bending to the side) of the vertebral column.

In everyday life, the spinalis muscles are used in many activities that involve extension of the vertebral column, such as looking upwards or stretching to reach for something on a high shelf. They are also used in activities that require rotation and lateral flexion of the vertebral column, such as twisting and turning the trunk.