Symptoms: Symptoms of sciatica range from local pain in the buttock or lower back to a sharp pain in the lower back and numbness and tingling down through the buttock, back of the thigh and into the lower leg and foot. If the cause is a herniated disk, the location of the pain will be specific — down the buttock, the back of the thigh, into the lower leg and in the big toe. This is called “radicular” or “radiating” pain.
If the cause of the pain is due to muscle or other tissue injury, it will be more diffuse and broadly felt (in the whole foot, for example, rather than just the toe). This is called “referred” pain. Referred pain can manifest as pain down one or both legs and can even switch from one leg to the other without warning or reason.
Overview: Sciatica commonly manifests itself as pain down the leg. Sciatica gets its name from the sciatic nerve, which has its roots in your lumbar (lower) spine, runs down through your thigh, into the leg and foot. Sciatica strikes when the sciatic nerve is irritated or aggravated, which can cause local pain as well as referred pain down the entire leg.
The sciatic nerve originates as five nerve roots exiting the lumbar spine. Its construction is analogous to the fingers and forearm, where the nerve roots that exit from the spinal cord are like your fingers and the nerve itself is like your forearm. As the sciatic nerve makes its way down the thigh, lower leg and into the foot, smaller nerves branch off, supplying messages to joints, muscles, ligaments and other soft tissue structures.
Sciatic pain may be aggravated by simply sitting, straining on the toilet, as well as coughing or sneezing. Generally twisting and bending-forward movements are the worst. For that reason, activities like golf, tennis, hockey and running commonly exacerbate symptoms of sciatica.
Diagnosing the condition is not particularly difficult, but determining its true cause can be tricky. There are five main conditions that can irritate or aggravate the sciatic nerve:
1. Disk herniations (neurogenic sciatica)
Bulging or herniated disks can cause compression on the nerve roots or initiate an inflammatory response that irritates nerve roots.
2. Muscles (myogenic sciatica)
3. Joints (scleretogenous sciatica)
The joints of the lower back (called “facets”) or pelvis, like the sacroiliac joints, are common causes of referred pain in the buttock and thigh and lower back.
4. Neurogenic claudication
The nerve roots that exit the spinal cord and form the sciatic nerve exit through little holes in the spine called intervertebral foramen (literally, holes between the vertebrae). Normally, the holes, formed by the bony spine, are big enough for the roots to exit through without difficulty. Sometimes, however, disease, trauma or arthritis can cause the diameter of these holes to diminish. This can aggravate or irritate the nerve and cause sciatica. In some cases the bony hole may have a spur or sharp bony structure that actually touches the nerve root, further aggravating the condition.
5. Space-occupying lesion
A space-occupying lesion refers to any growth that may be impinging on the spinal cord, nerve roots or peripheral nerves. Some of the causes of sciatica previously cited fall into this category (especially disk herniation or foraminal encroachment). However, there are other space-occupying lesions that can cause sciatica, including tumor growth, organ enlargement (from an underlying disease) or even severe scar tissue formation from previous surgeries. In addition, some women complain of sciatica after they receive an epidural during labor.
Once there is inflammation or irritation involving one of these conditions, a person may feel a “hot fire” in the lower back. It is essential that proper diagnosis of the true cause of your sciatica is diagnosed before treatment begins. Even if you are feeling better, the underlying cause may still linger, and flare ups are common unless the root cause of the problem is properly managed. Dr. Suzan Starler, D.C. has been treating patients with both acute and chronic sciatic pain since 1993. If you are experiencing sciatic pain, please do not hesitate to call for your consult!