Lumbar and Gluteal Motor Control in Chronic Low Back Pain

Non-specific low back pain (NSLBP) is defined as axial, non-radiating pain primarily located in the lower back, without signs of a serious underlying condition, spinal stenosis, radiculopathy, or another specific spinal cause. Its lifetime prevalence has been estimated to be as high as 84%, making it one of the most frequent reasons for medical consultation and one of the leading causes of disability worldwide. International clinical practice guidelines recommend therapeutic exercise as a first-line treatment; however, robust conclusions regarding which type of exercise provides the greatest benefit have not yet been established.

Neuromuscular control of the lumbar segment is essential both for the execution of motor tasks and for generating the forces required to stabilize the spine. NSLBP is associated with altered patterns of muscle recruitment, either as a contributing factor to pain onset or as a secondary response to pain. Specifically, altered muscle activation patterns have been observed during both static and dynamic movements, as well as in response to unexpected perturbations.

Individuals with NSLBP frequently exhibit impaired control of the deep trunk mus-cles, such as the transversus abdominis and the deep multifidus, which play a key role in maintaining spinal coordination and stability. Lumbar motor control programs aim to restore coordination, control, and functional capacity of these muscles. This is traditioally achieved by selectively training the deep trunk musculature and progressively integrating it into more complex static, dynamic, and functional tasks.

Moreover, recent studies have demonstrated a close relationship between low back pain and impaired hip motor control, particularly in the presence of reduced mobility and muscle weakness-primarily affecting the hip abductors and extensors-which leads to increased lumbar loading through compensatory mechanisms associated with altered motor patterns secondary to hip stiffness. To date, few randomized controlled trials have evaluated the effect of adding hip muscle strengthening exercises to lumbar motor control programs, and their results have been relatively heterogeneous and inconsistent. Previous studies reported no significant effects on pain or disability, most likely due to the use of unsupervised or time-limited programs, whereas others did observe improvements, although their interventions did not specifically target the transversus abdominis and deep multifidus muscles. Notably, the duration of all previously reported programs was less than 8 weeks, which is considered the minimum period required to achieve greater clinical benefits.

Inclusion criteria

• Age between 18 and 65 years.
• Non-specific low back pain with an intensity greater than 3/10 on a visual analogue scale.
• Symptom duration longer than 3 months.
• Sufficient understanding of spoken and written Spanish to adequately comprehend the intervention instructions and complete the assessments.

Exclusion criteria

• Severe lumbar or hip trauma within the previous 6 weeks.
• Prior vertebral fracture or lumbar disc herniation.
• Fibromyalgia.
• Active oncological disease.
• Diagnosis of a severe psychiatric disorder.
• Pregnancy.
• Uncontrolled rheumatologic pathology.
• Coexisting auto-immune pathology or chronic inflammatory disease.