Low back pain is the most common musculoskeletal condition worldwide. About 18% of the world's population suffers from low back pain and approximately 39% will suffer at least one episode of low back pain in their lifetime. Consequently, the costs associated with the treatment of patients with low back pain, absence from work , and disability are extremely high. The annual worldwide LBP incidence in adults to be 15% and the point prevalence to be 30% .A sedentary lifestyle with a lack of physical activity results in the loss of muscle power and strength and can be a predictor of LBP leading to recurrent LBP .In addition, a specific diagnosis of low back pain cannot be obtained in approximately 80% patients with low back pain, indicating that patients with low back pain are often diagnosed with nonspecific low back pain. Non-specific chronic low back pain (LBP) is a rather common and predominant health problem worldwide that affects people of all ages. Nonspecific low back pain is defined in the European guidelines for the management of chronic nonspecific low back pain (CNSLBP) as low back pain that is not attributable to a recognizable, specific pathology (e.g., infection, tumor, osteoporosis, fracture, structural deformity, and inflammatory diseases, such as ankylosing spondylitis, radicular syndrome, and cauda equina syndrome)Characteristic of chronic nonspecific low back pain are heavy pain, worsening with exertion and relieve with rest. In some cases the cause may be sprain or overstretch of a ligament or muscles. The endurance of trunk muscles is low in patients with low back pain as compared to individual without low back pain. The deep trunk muscles (Transverse Abdominis and Multifidus) responsible for maintaining the stability of spine. In other cases the cause may be a minor problem with the disc between two vertebrae or a minor problem with a small facet joint between two vertebrae. There may be other minor problems in the structures and tissues of the lower back that result in pain.The terminology becomes chronic low back pain when the symptom duration exceeds three months (nCLBP).Chronic low back pain (LBP) represents a significant healthcare problem that results in substantial costs to society .It is a prevalent condition that leads to increased disability and decreased quality of life.Non-specific LBP belongs to the group of musculoskeletal disorders, which include diverse conditions affecting muscles, bones, and/or joints of the limbs or the spine.
Non-speciﬁc low back pain is deﬁned as low back pain not attributable to an identifiable, known speciﬁc pathology. Non-specific low back pain accounts for over 90% of patients presenting to primary care and these are the majority of the individuals with low back pain that present to physiotherapy.Objective of this study is to compare the effects of rhythmic stabilization and McKenzie technique on pain and function in patients with non-specific chronic low back pain