Deeper into Multifidus

Multifidus is the important core muscle on the back

From sacrum all the way up to neck

Every unit goes 2-4 segment above toward the spinous process.

Play an important role as a lumbar stabilizer

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Due to the sarcomere length change,

Multifidus generates max strength output during trunk flexion.

That somehow implies the ability as a trunk stabilizer on the saggital plane.

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Many researches showed that multifidus dysfunction occurs among chronic low back pain population.

Also, form image studies, the fat will infiltrate multifidus tissue, A.K.A multifidus atrophy.

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Thus, it's important to assess and activate multifidus for low back pain population.

There are two excellent movements can be used to assess multifidus.

Multifidus Lifting Test (MLT) and multi-segmental extension test

MLT is performed under quadruped position

The subject needs to get the neutral spine first, then raising arm or leg or both.

Belly dropping or cannot maintain the neutral spine is considered positive

Multi-segmental extension is another easy PE.

There are two signs we need to watch out

1. Hyperlordorsis of the lumbar

2. Any hinge point on the spine

Both signs tell you that multifidus is dysfunction that cannot distribute the pressure properly.

After dealing with the structural issue and motor control issue,

we need to teach them how to use their multifidus.

Below are two exercises I use a lot to activate multifidus.

Modified Superman by Dr. Kathy Dooley

Original superman may over recruit neck and erector spinae during practice,

which might make the symptom worse.

Instead, you can add a pulling movement of the arms before raising limbs.

That can help you recruit core muscles to stabilize ribs during movement.

Sidelying Mf activation

Think about there's a line connecting your groin and lumbar spine

Contracting this line gently and lifting lumbar vertebra up slightly

Then you can give light resistance to push the pelvis forward

Another hand can touch their back to feel if the Mf is contracting or erector is over activating.

Multifidus is core of the back.

It assists us against gravity and rotation.

In order to stabilize low back spine, 

multifidus is one muscle you can not neglect.

Ref

1. Freeman, M. D., Woodham, M. A., & Woodham, A. W. (2010). The role of the lumbar multifidus in chronic low back pain: a review. PM&R, 2(2), 142-146.

2.Ward, S. R., Kim, C. W., Eng, C. M., Gottschalk IV, L. J., Tomiya, A., Garfin, S. R., & Lieber, R. L. (2009). Architectural analysis and intraoperative measurements demonstrate the unique design of the multifidus muscle for lumbar spine stability. The Journal of Bone and Joint Surgery. American volume.91(1), 176.

3. Fortin, M., & Macedo, L. G. (2013). Multifidus and paraspinal muscle group cross-sectional areas of patients with low back pain and control patients: a systematic review with a focus on blinding. Physical therapy, 93(7), 873-888.

4. Kjaer, P., Bendix, T., Sorensen, J. S., Korsholm, L., & Leboeuf-Yde, C. (2007). Are MRI-defined fat infiltrations in the multifidus muscles associated with low back pain?. BMC medicine, 5(1), 2.