The lumbar spine, or low back, is a remarkably well-engineered structure of interconnecting bones, joints, nerves, ligaments, and muscles all working together to provide support, strength, and flexibility. However, this complex structure also leaves the low back susceptible to injury and pain.
The low back supports the weight of the upper body and provides mobility for everyday motions such as bending and twisting. Muscles in the low back are responsible for flexing and rotating the hips while walking, as well as supporting the spinal column. Nerves in the low back supply sensation and power the muscles in the pelvis, legs, and feet.
Most acute low back pain results from injury to the muscles, ligaments, joints, or discs. The body also reacts to injury by mobilizing an inflammatory healing response. While inflammation sounds minor, it can cause severe pain.
There is a significant overlap of nerve supply to many of the discs, muscles, ligaments, and other spinal structures, and it can be difficult for the brain to accurately sense which is the cause of the pain. For example, a degenerated or torn lumbar disc can feel the same as a pulled muscle – both creating inflammation and painful muscle spasm in the same area. Muscles and ligaments heal rapidly, while a torn disc may or may not. The time course of pain helps determine the cause.
Images of Tailbone pain(1) & compressed spinal canal(2)
Types of Low Back Pain
There are many ways to categorize low back pain – two common types include
Mechanical pain. By far the most common cause of lower back pain, mechanical pain (axial pain) is pain primarily from the muscles, ligaments, joints (facet joints, sacroiliac joints), or bones in and around the spine. This type of pain tends to be localized to the lower back, buttocks, and sometimes the top of the legs. It is usually influenced by loading the spine and may feel different based on motion (forward/backward/twisting), activity, standing, sitting, or resting.
Radicular pain. This type of pain can occur if a spinal nerve root becomes impinged or inflamed. Radicular pain may follow a nerve root pattern or dermatome down into the buttock and/or leg. Its specific sensation is sharp, electric, burning-type pain and can be associated with numbness or weakness (sciatica). It is typically felt on only one side of the body.
There are many additional sources of pain, including claudication pain (from stenosis) myelopathic pain, neuropathic pain, deformity, tumors, infections, pain from inflammatory conditions (such as rheumatoid arthritis or ankylosing spondylitis), and pain that originates from another part of the body and presents in the lower back (such as kidney stones, or ulcerative colitis).
It is also possible for low back pain to develop with no definitive cause. When this happens, the primary focus is on treating the symptoms (rather than the cause of the symptoms) and the patient’s overall health.
For subacute and chronic lower back pain, a thorough diagnosis is important to lay the foundation for appropriate treatment and rehabilitation. Lower back pain treatment reduces the likelihood of recurrent back pain flare-ups and helps prevent the development of chronic lower back pain.
- Lumbar surgeries
- Lumbar decompression surgeries
A decompression surgery removes whatever is pressing on a nerve root from the spinal column, which might include a herniated portion of a disc or a bone spur. There are two primary types of decompression for low back pain.
- Microdiscectomy is a minimally invasive procedure for patients with a lumbar herniated disc causing radicular leg pain (sciatica).
- Laminectomy removes part of the layer of the bone or soft tissue that is compressing a nerve or multiple nerve roots. A laminectomy will typically be performed for someone with leg pain and/or weakness from spinal stenosis caused by changes in the facet joints, discs, or bone spurs.
A decompression surgery can be performed with open or minimally invasive techniques with relatively small incisions, and minimal discomfort and recovery before returning to work or other activities. Most of these procedures are now being done as day surgery or with one overnight stay.
3. Fusion surgeries(lumbar spinal fusion)
Sometimes lower back pain may occur for kidney diseases.