Assessment of Core Muscles Endurance, Lumber Curvature and Function in Smartphone-addicts With Nonspecific Low Back Pain

Inclusion Criteria: * University students who have been experiencing chronic nonspecific low back pain for a period of at least six months * Both genders * Smartphone addicted cut-off points for smartphone addiction at 31 for men and 33 for women in smartphone addiction scale short version * Age is ranged from 18-25 years old Exclusion Criteria: * Patients will be excluded if they don't fulfil the inclusion criteria or if they have one of the following: * Athletes * Any history of spinal trauma or dysfunction * Systemic disease presenting in the back (such as ankylosing spondylitis) * Spinal deformity * Leg length discrepancy * History of spinal, abdominal or orthopedic surgery * Patients who are under treatment with nonsteroidal anti-inflammatory drugs