Lower back pain can be triggered by pathology affecting the anatomical structures around the lower back such as muscles, joints, ligaments, nerves or discs.
In many cases, no definitive cause for the low back pain can be identified and it is then referred to as non-specific low back pain. In non-specific low back pain no fractures, cancer, infection or any other specific spinal condition can be identified as a cause of the pain.
Compression of the nerve as it exits the spinal column is common (often called a ‘pinched nerve’), and is often associated with pain referring down the leg.
Lower back pain can also be referred from internal organs such as the uterus. A very small percentage of lower back pain is caused by serious pathology such as cancer.
What is the difference between acute and chronic low back pain?
Acute (<1 month) and sub-acute (1-3 months) low back pain is a consequence of injury and it has a function: to protect the injured structures or tissues like the muscles, joints, discs or ligaments.
If pain persists after three months, the low back pain is classified as chronic.
Chronic pain does not serve a useful function, but is rather a consequence of the maladaptive neurophysiology which results in excessive sensitisation of the nervous system.
Patients with chronic low back pain experience a lot of anxiety and fear about their low back pain and thoughts such as "my low back pain will make me end up in a wheel chair" and "I'll have to undergo surgery in order to fix my back" are common.