This study will be conducted to investigate the correlation between the flexibility of hip muscles; hip flexors (iliopsoas, rectus femoris), hip extensors (hamstring), hip internal rotators, hip external rotators, hip adductors and hip abductors with pain intensity and disability level among patients with chronic nonspecific low back pain
Chronic nonspecific low back pain for at least 3 months.
Age of the patient will range from 20 and 45 years.
Pain intensity of three or higher based on the visual analogue scale (VAS, 0-10 scale).
.Body Mass Index from 18-25 kg/m2.
spinal surgery, spinal or pelvic fracture.
ankylosing spondylitis or rheumatoid arthritis.
spondylolisthesis or spondylolysis, neurological disorders.
spinal inflammation or tumor. osteoporosis.