Non-specific chronic low back pain

Human's spine can be compared with a skyscraper. It defies gravity, and defines people as vertical bipeds. This infrastructure forms the biological machine that secures the kinetic chain and transfers biomechanical forces into the controlled functional activity. The spine works as a channel for the precious neural structures and plays and important role in walking and lifting. Being subjected to the aging, human's spine adapts to the biomechanical loading through compensatory structural and neurochemical changes. Some changes cannot be adapted and that is why they cause pain. (Wheeler & Murrey 2005, 421-52.)

Low back pain can be acute and chronic. Acute low back pain lasts for 6 weeks of less. The pain can be sharp and severe. It might be caused by injury, trauma or disease. However, the pain can be dull sometimes and felt in different areas. This type of pain limits range of motion and daily activities. Chronic low back pain is a low back pain, persisting for 12 weeks or more. The pain is usually deep and dull. It becomes worse while long sitting or lying (Nusbaum, 2012).

According to diagnoses, low back pain can be divided into three categories. The first group is rare and it contains serious low back pain. It is only 1% of all low back pain cases that occur with patients. The second group describes radicular pain that occur because of nerve root irritation. It is only 5% of all low back cases. The last and the main group is a group of non-specific low back that happens in more than 94% cases (Luomajoki, 2010, 21).

Non- specific or nonradical low back pain is defined as low back pain that doesn't belong to any recognizable, known specific pathology (infection, tumor, osteoporosis, ankylosing spondylitis, fracture, inflammatory process, radicular syndrome, cauda equine syndrome) (Paatelma, 2011, 14). Low back pain in terms of nonradical or mechanical back pain describes the nature in which the patho-anatomical etiology is not known. It is associated with neurological symptoms or signs (Paatelma, 2011, 15). Generally, the pain is located in the spine or paraspinal areas (or both) and does not radiate into the leg. Moreover, nonradical low back pain is not associated with spinal nerve root compression. (Kerry H. Levin) Non-specific low back pain can be classified into 3 groups according to the time period: acute pain from 0 up to 6 weeks, subacute pain from 6 up to 12 weeks and chronic pain starting from the 12^th week (Luomajoki, 2010, 21).

New classification system was set by O'Sullivan (Table 2). According to his work, only 5-10% cases of low back pain are specific. They have clear medical diagnoses. Other 90-95% cases are non-specific. Non-specific group is divided into non mechanical and mechanical (Luomajoki, 2010, 7).

Table 2. Classification of non-specific low back pain by O'Sullivan. (Luomajoki, 2010)

Active movement control of the lumbar spine in action is called movement control impairment. Patients with low back pain usually do not have limitation in movement direction but they suffer from sustained postures. Movement control dysfunctions are also known as movement impairment syndromes. Clinically found instability in the lumbar spine and segmental instability can be called as a motor control impairment. These patients can also be described as patients with a postural syndrome. The definition of instability is often used to explain low back pain (Luomajoki, 2010, 8).

Many factors play an important role in the etiology of low back pain. Risk factors can be divided into several groups such as: physical load factors, psychosocial, psychological and individual factors (Paatelma, 2011, 13). There are different factors that influence on low back pain and movement control. It is evidence based that cognitive and psychosocial factors play more important role in chronic low back pain than any anatomical issues (Luomajoki, 2010, 21). Classification of cognitive and psychological factors is presented in Table 3.

Table 3. Classification of cognitive and psychosocial factors. (Website of Dissertations in Health Sciences)