Lumbar Multifidus Dysfunction and Chronic Low Back Pain: Overview, Therapies, and an Update on the Evidence.

Background: Chronic low back pain (CLBP) is a common and harmful medical condition, and in many cases, no specific radiographic cause is identified. Many cases of CLBP are refractory to treatment and will recur after the initial episode. Dysfunction of the lumbar multifidus muscle (LMM) has been increasingly identified as a possible cause of non-specific CLBP (NSCLP).

Methods: A review was conducted on the multifidus anatomy, dysfunction, diagnosis, and treatment literature.

Results: Multifidus dysfunction has been increasingly recognized as a potential contributor to the pathogenesis of non-specific chronic low back pain. Multifidus dysfunction is thought to arise from reflex inhibition stemming from an initial insult, which decreases spinal stability and predisposes patients to further injury. Therapeutic approaches aimed at addressing multifidus dysfunction include traditional conservative management, such as patient education, non-steroidal anti-inflammatory drugs, spinal manipulation, and physical therapy. These therapies aim mainly to achieve pain relief. Treatments that restore natural multifidus function include motor control exercises and restorative neurostimulation.

Conclusion: Non-specific chronic low back pain is correlated with multifidus atrophy, fatty infiltration, and abnormal lumbar multifidus muscle function. This finding highlights the need for further research and clinical trials on targeted therapeutic approaches. Existing treatments on the lumbar multifidus muscle include motor control exercises and restorative neurostimulation. Unlike many conventional treatments that primarily provide symptom relief, these therapies aim to restore natural multifidus function, offering a rehabilitative rather than purely palliative approach. Motor control exercises have been shown to improve symptoms in cases of CLBP, but there is mixed evidence of their effectiveness relative to standard physical therapy. Restorative neurostimulation is a promising intervention that has been shown to provide significant, durable improvements to disability and pain. Further research on restorative therapies should be conducted using rigorous control protocols and comparative analyses with other CLBP treatment modalities.