“The Deep Core Stability Muscles of the Lower Spine have been identified as:”

• ‘The Transversus Abdominis (TA) is the deepest abdominal muscle. It is the "corset muscle" of the spine and pelvis.’ 

• ‘Multifidus (MF) muscles are very short muscles running from the transverse processes (on the sides) of one vertebra up to the spinous process (the middle of the back) of the next vertebra upwards.’

• ‘The TA and the MF work in conjunction with your pelvic floor and diaphragm to make a flexible but stable region around your lumbar spine. It is this ability to stabilise your lumbar spine in its many positions that enables you to overcome back problems and reduce your chances of a recurrence.’

Reference:http://physioworks.com.au/FAQRetrieve.aspx?ID=31027

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