Lower back muscles

Erector spinae

This is a group of muscles located on the back, either side of the spine. They pull back the trunk to make leaning back possible (spine extension).

Multifidis

This is the deepest muscle of the back associated with the spine. It helps to extend and rotate the spine.

Quadratus lumborum

This is a fleshy muscle which forms part of the posterior abdominal wall. It laterally flexes the spine.

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