563- How Spinal Adjustments Impact Multifidus Muscle Firing in Acute Low Back Pain

Spinal manipulation significantly impacts the neuromuscular control of the lumbar multifidus, the primary segmental stabilizer of the spine. Research utilizing fine-wire EMG under CT guidance demonstrates that a single high-velocity, low-amplitude adjustment reduces motor unit firing variability in patients with acute low back pain. This reduction in signal "jitter" brings muscle firing patterns closer to those observed in pain-free individuals, indicating a more stable and efficient neural output. While the adjustment does not resolve pre-existing deficits in left-to-right bilateral coordination, it effectively optimizes the firing consistency of deep stabilizing muscles. Integrating these findings into clinical practice suggests that delivering an adjustment prior to movement-based rehabilitation may enhance patient outcomes by ensuring the multifidus is firing more regularly, thereby providing a more stable foundation for subsequent corrective exercises and functional recovery.