In part three of our series on "core" trunk muscles and back pain we look at the muscle called the transversus abdominus. The transversus abdominus is the "cumberbun" muscle of the abdomen. It is the deepest of all the abdominal muscles and is oriented from side to side instead of the abdominal muscles we usually see that go from up to down. This muscle is considered one of the most important abdominal muscles to prevent back pain. Here's why. A group of physical therapists in Australia who study back pain found out that whenever we even think about moving our arm or leg muscles the transverse abdominus muscle contracts and steadies the lower back. The transverse abdominus contracts and steadies the spine by providing "squeezing support for the back. Much like you could squeeze one end of a tube of toothpaste and see the other end of the tube straighten out, the transverse abdominus squeezes the spine and abdomen and "pushes up" the trunk. These physical therapist researchers found out that in people who have back pain their transverse abdominus loses its ability to contract and take pressure off the spine. This is one big reason that the transversus abdominus muscle is important in treating back pain. In the next installment of our series we will look at how you can train this muscle and improve back pain symptoms.
Chris Dollar, DPT, PT, FAAOMPT is a clinical specialist physical therapist and Coordinator of Clinical Education for OrthoCarolina. His area of practice focus is in the evaluation and treatment of spinal conditions.