The Role of the Semi-Spinalis, Rotatores, and Intertransversarii Muscles in Prone Spinal Extension

Introduction

Spinal extension is a fundamental movement pattern that involves the posterior chain muscles. The primary muscles involved in spinal extension from a prone position are the erector spinae group, which includes the iliocostalis, longissimus, and spinalis muscles. However, recent research suggests that other muscles such as the semi-spinalis, rotatores, and intertransversarii also play a key role in spinal extension from a prone position. This article aims to discuss the role of these muscles in more detail.

Anatomy of the Semi-Spinalis, Rotatores, and Intertransversarii

The semi-spinalis muscles are deep muscles located in the back of the neck, thoracic and lumbar region. They originate from the transverse processes of the vertebrae and insert into the spinous processes of the vertebrae several segments above. The rotatores muscles are located deep to the multifidus muscles and also originate from the transverse processes of the vertebrae and insert into the spinous processes of the vertebrae a few segments above. The intertransversarii muscles are small muscles located between the transverse processes of adjacent vertebrae, which help to stabilize the spine.

Role of Semi-Spinalis, Rotatores, and Intertransversarii in Spinal Extension

When performing spinal extension from a prone position, the erector spinae group extends the spine by contracting bilaterally. However, recent research suggests that the semi-spinalis, rotatores, and intertransversarii muscles also contribute to spinal extension. The semi-spinalis muscles have been found to be particularly active during spinal extension from a prone position. In addition, the rotatores muscles have also been found to contribute to spinal extension in a similar manner as the multifidus muscles, which have been previously shown to stabilize the spine and control spinal alignment. Moreover, the intertransversarii muscles have been found to play a significant role in spinal stabilization during extension movements.

Conclusion

In conclusion, while the erector spinae group is the primary muscle group responsible for spinal extension, the semi-spinalis, rotatores, and intertransversarii muscles also play an important role in the movement. These muscles are crucial for spinal stability and control, and their activation during spinal extension from a prone position can lead to a more comprehensive activation of the posterior chain. Further research is warranted to investigate the role of these muscles further in spinal extension and how their function can be optimized during exercise programming.

References

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