The back muscles associated with the vertebral column are divided into superficial, intermediate, and deep layers. The superficial layer contains the splenius muscles closely associated with the cervical vertebra, which support head and neck movements, while the intermediate layer contains erector spinae muscles. The erector spinae are the largest group of long back muscles on either side of the vertebral column extending from the pelvis to the neck. This group comprises spinalis, longissimus, and iliocostalis muscle columns, subdivided into different parts based on their axial skeleton attachments. For example, the iliocostalis muscles have three horizontal divisions: the iliocostalis cervicis, iliocostalis thoracis, and iliocostalis lumborum. The bilateral contraction of these muscles facilitates the vertebral column extension, while unilateral contraction facilitates lateral flexion on the same side. In contrast, the deep layer comprises the semispinalis, multifidus, and rotatores muscles. These muscles stabilize individual vertebrae positions during localized movements. For instance, the semispinalis thoracis, spanning between the sixth cervical and tenth thoracic vertebrae, specifically aids the extension, lateral flexion, and thoracic spine rotation.