Myofascial sling
Understanding the myofascial sling
The myofascial sling is a system of interconnected muscles, fascia (connective tissue), and ligaments that work together to transmit force and stabilize the body during movement. These slings help coordinate body segments and facilitate efficient movement. There are four primary myofascial slings in the body:
Anterior Oblique Sling (AOS): Involves the external obliques, internal obliques, and the opposing adductor muscles.
Posterior Oblique Sling (POS): Involves the latissimus dorsi, gluteus maximus, and the thoracolumbar fascia.
Lateral Sling: Includes the gluteus medius, tensor fascia latae (TFL), and the opposing adductor complex.
Deep Longitudinal Sling (DLS): Involves the erector spinae, thoracolumbar fascia, and biceps femoris.
Physiotherapists and Myofascial Sling Work
Physiotherapists use manual therapy and exercises to target and improve the function of these myofascial slings, particularly when there are issues related to body mechanics, postural imbalances, or joint dysfunctions like sacroiliac joint (SIJ) problems.
Here’s how they approach the myofascial sling system:
Manual Therapy:
Myofascial release: This involves applying sustained pressure to fascial restrictions to loosen or release them, improving tissue flexibility and reducing pain. It helps the muscle groups in the sling move more freely.
Trigger point therapy: This targets specific areas of tightness or tenderness within the muscles, helping to alleviate pain and tension that may be disrupting the function of the myofascial sling.
Joint mobilizations or manipulations: Mobilizing the joints, such as the sacroiliac joint, helps restore motion and reduce stiffness, allowing the surrounding muscle and fascial systems to work more effectively.
Exercise Interventions:
Sling-specific exercises: Exercises are prescribed to engage and strengthen muscles within the myofascial slings. For example, exercises like bird-dog, side planks, or chop and lift patterns might target the anterior or posterior oblique sling.
Core stabilization: Improving core strength is crucial, as the core acts as a central hub for the slings. Exercises like dead bugs, planks, and paloff presses are used to stabilize the trunk.
Functional training: Physios emphasize movement patterns that replicate real-life activities, training the slings in ways that simulate daily or sport-specific actions. This ensures that improvements translate into better movement outside of the clinic.
Force Closure of the Sacroiliac Joint (SIJ) and Myofascial Slings
Force closure refers to the way muscles, ligaments, and fascia actively engage to stabilize a joint. The sacroiliac joint, located between the sacrum (base of the spine) and the ilium (part of the pelvis), relies heavily on muscular and fascial structures for stability due to its limited bony congruence. Dysfunction of the SIJ can result in pain or instability, often due to issues with force closure.
The myofascial slings, particularly the posterior oblique sling and deep longitudinal sling, play a key role in force closure of the sacroiliac joint.
Posterior Oblique Sling: The latissimus dorsi and contralateral gluteus maximus work together with the thoracolumbar fascia to provide stability during movements like walking or running. If these muscles are weak or imbalanced, it can reduce the effectiveness of force closure.
Deep Longitudinal Sling: This sling contributes to the vertical stability of the body and assists in stabilizing the sacroiliac joint through the erector spinae, biceps femoris, and sacrotuberous ligament. Dysfunction in this system can lead to inadequate force transmission and poor SIJ stability.
By improving the function and strength of the myofascial slings, physiotherapists can enhance force closure at the SIJ, reducing pain and improving stability. Strengthening exercises and mobilization techniques help ensure the muscles and fascia can properly transmit force and maintain proper alignment in the sacroiliac region. This can be especially important for people experiencing SIJ dysfunction, as it often results from weakness, instability, or improper muscle activation patterns in the myofascial system.
