Patients with chronic lower back pain caused by lower back muscles in spasm results in patients having difficulty in straightening the spine. In such a situation, the abdominal wall muscles have less opposition and become tight and shortened aggravating the forward bent posture.
To test the strength of the abdominal wall, the patient can lie on his back and attempt to lift the head forward against resistance.
Often, abdominal wall pain may be the presenting feature in a patient who has had lower back pain and stiffness for some time. He may have gotten used to these lower back symptoms and a careful history for such must be uncovered to get to the root of the abdominal wall symptoms.
Palpation for presence of tender muscle knots and bands in the abdominal wall should always be performed for consideration of presence of myofascial syndrome.
The muscles that comprise the abdominal wall are:
- Rectus abdominis
- External oblique
- Internal oblique.
Nerve supply: Lower thoracic nerves from T6 to L1.