The multifidus muscle is a deep-seated, segmented muscle located along the spine, playing a significant role in overall back health. These small muscles lie close to the spinal column, beneath larger, more superficial back muscles. They are continuously active during nearly all daily movements, highlighting their importance in maintaining spinal function and stability.
Anatomy of the Multifidus
The multifidus muscle extends along the entire length of the spine, from the sacrum at the base to the cervical region in the neck. It is most developed in the lumbar (lower back) area. The muscle is composed of numerous bundles that fill the grooves on either side of the spinous processes of the vertebrae.
These bundles originate from various points along the sacrum and vertebrae. Their fibers extend obliquely upward and medially, inserting into the spinous process of vertebrae located one to four segments above their origin. The deepest layers connect only two adjacent vertebrae, while more superficial layers can span up to four segments. This layered arrangement allows for precise control over individual spinal segments.
Key Roles of the Multifidus
The multifidus muscle performs several actions fundamental to spinal health and movement. Its primary function is to provide stability to the spine, both at individual segmental levels and globally. This muscle contributes a significant portion of the total muscular stability applied to the back. The stability it provides helps each vertebra function more effectively, reducing friction and potential degeneration of joint structures during everyday activities.
Beyond stability, the multifidus also facilitates precise spinal movements, including extension, lateral flexion, and contralateral rotation. Its unique anatomical position allows it to finely control these movements. The multifidus also plays a proprioceptive role, helping the body sense the position and movement of the spine. This sensory feedback is important for coordinating movement and maintaining proper posture. It is recruited before larger, more superficial muscles, preparing the vertebrae to avoid unnecessary motion.
Multifidus and Low Back Health
Dysfunction of the multifidus muscles is strongly associated with low back pain. When these muscles become weak or atrophy, often replaced by fatty tissue, it can lead to spinal instability and contribute to chronic pain. This dysfunction can persist even after the initial pain has subsided, which may explain the high recurrence rates of low back pain.
Injury to the spine can lead to an inhibition of the multifidus, where the muscle fails to activate properly. In such cases, larger, superficial muscles may attempt to compensate, which can create additional problems for facet joints and ligaments. Targeted attention to multifidus function is important for recovery and long-term spinal well-being.
Strengthening the Multifidus
Supporting and improving multifidus function often involves a focus on core stability and targeted movements. General principles for strengthening include engaging in exercises that promote deep abdominal muscle activation, such as the transversus abdominis and pelvic floor muscles, as these muscles work synergistically with the multifidus. Exercises that involve controlled, subtle movements of the spine can help re-engage and strengthen the multifidus.
Exercises that benefit the multifidus often involve maintaining neutral spine positions during movement or performing exercises that require precise control over individual spinal segments. Examples include drawing in the abdomen without bracing, or gentle spinal extension movements. Professional guidance from a physical therapist or exercise specialist is recommended to ensure exercises are performed correctly and safely, maximizing their benefit for multifidus activation and overall spinal health.