TABLE 1.

Exclusion criteria.

✓ Suspected serious spinal pathology (e.g., fracture, inflammatory/infections spinal disease, cauda equina syndrome, malignancy, metastasis, unexplained weight loss or fever, neurological disorder)

✓ Specific pathology that cause back pain, such as internal organ disease, active inflammatory spondyloarthropathies, recent spinal trauma or surgery

✓ Presence of major pain or injury to other body regions in the previous 12 months

✓ Pregnancy

✓ Renal pathologies that can alter creatinine and urinary cytokines levels

✓ Sleep disorders (such as sleep apnea and snoring)

✓ Known depression, anxiety or other psychological disorders