Degenerative conditions in the vertebrae of your lumbar spine, or low back, are a common source of leg pain.
If you are experiencing leg pain, the source of your discomfort may not actually be in your leg, but in your lower back, or lumbar spine. The lumbar spine is a common source of back pain because it bears more body weight than any other section of the spine and is also subject to a significant amount of stress and force, be it from lifting a load of laundry or blocking a tackle.
When you feel pain, it's a reaction to signals transmitted throughout your body. These signals are sent from the pain source through the nerves in the spinal cord and into the brain, where they are perceived as pain. Problems that originate in the lumbar spine may result in pain and other symptoms, such as tingling, numbness and muscle weakness, which may be localized in the lower back and/or extend into the hips, buttocks and/or legs. The medical term for symptoms that radiate into the extremities is radiculopathy, derived from the Latin words "radix," or roots, and "pathos," which means disease.
Acute Pain vs. Chronic Pain
Acute pain is commonly described as sharp and severe; it tends to come on suddenly but also improve with time and short-term conservative treatment, such as medication, exercise, physical therapy or rest.
Chronic pain is commonly described as a deep, aching, dull or burning pain, and may be accompanied by numbness, tingling and/or weakness that extends into the extremities. Chronic pain tends to last a long time and is not relieved by conservative care.
What's Causing My Leg Pain?
The five vertebrae of the lumbar spine (L1-L5), located directly below the thoracic spine (mid-back) and directly above the sacrum, are separated by shock-absorbing intervertebral discs and supported by muscles and ligaments. These discs are very important for the normal mobility and function of your back. Over time, age, genetics and everyday wear-and-tear can contribute to deterioration of these discs, which, when healthy, act as "cushions" for the individual bones of the spine, or vertebrae.
Each disc is made up of two parts:
- The nucleus pulposus - the soft, gel-like center of the disc.
- The annulus fibrosis - the strong, fibrous outer ring that surrounds and supports the nucleus pulposus.
Over time, intervertebral discs can become dried out, compressed or otherwise damaged, due to age, genetics and everyday wear-and-tear. When this happens, the nucleus pulposus may push through the annulus fibrosis. Disc degeneration also may result in bone spurs, also called osteophytes, or spinal stenosis, the narrowing of the area of the spine where the nerve leaves the spine and travels to the rest of the body.
If disc or bone material pushes into or impinges on a nearby nerve root and/or the spinal cord, it may result in pain, numbness, weakness, muscle spasms and loss of coordination, both at the site of the damage and elsewhere in the body. Sciatica - often described as pain that begins in the hip and buttocks and continues all the way down the leg - is one example of a radicular symptom that may be caused by damage or deterioration in the lumbar spine.
These symptoms and the conditions that cause them are collectively referred to as degenerative disc disease, if the condition has become chronic over time. Similar symptoms, however, may occur suddenly if the disc nucleus dislodges acutely and causes nerve root compromise, a condition referred to as a herniated disc.
When Should I See My Doctor?
If you are suffering from chronic leg, buttock or hip pain or pain as a result of a physical trauma involving your lower back, such as a fall or car accident, you should seek treatment from a physician.
Consult a physician immediately if you:
- Are experiencing numbness in, or having difficulty moving, your extremities
- Experience bladder control loss or impairment
- Develop a fever or severe headache
- Are over 60 and have been taking steroids for a long period of time
- Experience chest pain or pain in the left arm
- Are pregnant
- In instances of acute back pain, do not experience any improvement after 72 hours of self-treatment at home
- Have experienced chronic leg pain for more than 6 weeks
If you are experiencing leg pain, talk to your doctor about appropriate treatment options. Identifying the cause of your leg pain, alleviating the pain - either at home or with your physician's help - and avoiding re-injury are key to the healing process.