If you have experienced low back pain with shooting pain down your leg, then it just might be sciatica. The pain can be in the front, the side, or the back of the leg. Other symptoms include numbness, tingling, altered sensation, and weakness. Usually one leg is affected, but it is possible to have both legs involved. This is usually a more serious sign, especially if there is loss of bowel/bladder/sexual function or loss of sensation of the inside of the thighs. Sciatica is not really a specific diagnosis but is more just describing a symptom. You might also call sciatica a “pinched nerve”. Where the nerve is being pinched and what is doing the pinching is more complicated.
As you might know, the different nerves in your low back go to different places in your legs. The affected area of the leg depends on which nerves are being damaged. The middle nerves of the lumbar spine tend to affect the front of the leg, lower nerves of the lumbar spine tend to affect the side of the leg, while nerves of the upper sacral spine tend to affect the back of the legs. Another sign of sciatica is that symptoms travel below the knee. This indicates a truly neurologic pathology that has a high risk of chronicity.
I want to mention here that the term sciatica is derived from the sciatic nerve, but sciatica is often used simply to refer to pain or back pain that runs down the leg. This can sometimes cause confusion. For the sake of this article, I will include several conditions which can present with these symptoms.
Vertebral discs can change shape or even herniate. A disc bulge is a change in the shape of the disc. A herniation is when the gel-like center of the disc protrudes out of the normal confines of the disc. These changes in the disc can end up putting pressure on the nerves of the spine. The disc can herniate left, right, or center. Down in the lumbar region a central disc herniation can lead to a condition called Cauda Equina Syndrome that is serious and requires immediate surgery in order to prevent permanent loss of bowel/bladder/sexual dysfunction. A herniation to the left or right will likely put pressure on the nerve root. The symptoms depend on the amount of irritation/pressure and the level of the disc. Disc pathology is the most common reason for sciatica and is considered the cause in the classic definition of true sciatica.
Spondylosis and Spinal Stenosis
Degenerative joint disease, degenerative disc disease, and osteoarthritis together are lumped into the term spondylosis when they occur in the spine. Spinal Stenosis is the term used to indicate narrowing of the passageway of the nerves. Spondylosis can lead to spinal stenosis. The loss of disc space narrows the diameter of these nerve passageways from top to bottom, and bone spurs can narrow the passage ways from front to back or side to side. Bone spurs and disc shape changes can also narrow the diameter of the spinal canal (where the cord and several nerve roots exist) also causing Cauda Equina-like symptoms. Additionally, people are sometimes born with already narrow nerve passage ways and this puts them at even greater risk of developing sciatica and other related neuropathies. Of course, anything that changes the shape, position, or curvatures in the spine can also lead to stenosis such as pregnancy, Scheuermann's disease, or scoliosis.
Other Space-Occupying Lesions and Pathology
Some more serious reasons for sciatica are tumors, fractures and infections. These situations warrant immediate medical intervention. A tumor grows and occupies space that can put pressure on nerves. Fractures may lead to bone fragments putting pressure on nerves and/or cause instability of the spine that results in nerve compression. An infection can also create changes and inflammation in the spine that can lead to these sorts of neuropathies. These pathologies are the first things that should be ruled out during an initial examination.
There is a particular muscle in the buttocks called the piriformis. The sciatic nerve runs right under this muscle. A tightening or contracture or over development of this muscle (usually compensation for gluteal weakness) can put pressure on the sciatic nerve. In a small portion of the population, the sciatic nerve travels either partially or entirely through the piriformis muscle. If the piriformis is chronically contracted, then it can strangle the sciatic nerve producing sciatica. However, piriformis syndrome is traditionally not considered true sciatica.
This is a condition where the lateral femoral cutaneous nerve (a nerve that runs down the outer thigh) can be compressed or injured. This has been nicknamed the “skinny pants syndrome” because tight fitting pants or belt is the underlying cause. The nerve becomes entrapped around the front of the hip and groin region as the nerve passes from the pelvic area to the lateral thigh. Motor vehicle accidents can also cause lesions of this nerve from contact of the seat belt. There are also several other less common causes for compression and injury to this nerve. This condition is also not included in the classic definition of sciatica.
Iliotibial Band Syndrome and Trochanteric Bursitis
This is another biomechanical issue that can cause pain running down the leg with occasional neurological implications and can be associated with back pain. There is a muscle called the tensor fascia latae (TFL). Tightening of the TFL can create excessive tension of a band of fibrous connective tissue that runs down the outside of the leg called the iliotibial band (ITB). This tension puts pressure against the trochanteric bursa which is located around the hip bone. This whole complex of problems is referred to as ITB syndrome and trochanteric bursitis and they usually occur altogether. Pain often starts in the hip and travels down the outer thigh to the knee. Muscle spasm, swelling, and general tension can lead to nerve compression occasionally. This makes the problem look like sciatica, but again, this is not true sciatica.
Ever had chicken pox? This is caused by the varicella zoster virus. Like all other herpes viruses, it actually lives in your nerves imbedding itself into the DNA of the nerve cells. It is there forever. It is usually dormant but can become active again leading to herpes outbreaks. When chicken pox reactivates, it is called herpes zoster. This typically happens to older adults but can happen in younger people too. Before the full rash appears, a person can have neurological symptoms including pain and numbness. If the affected nerve is in the low back and leg, then this virus can present just like sciatica.
General Kinetic Chain Dysfunction
In some cases, pain can appear to shoot down the leg with back pain not because of a pinched nerve, but because of a problem in the kinetic chain. A kinetic chain is the link between several consecutive joints and the muscles and other soft tissue involved in that linkage. It is a head-bone-is-connected-to-the-foot-bone situation. Here is an example: A patient has a “flat foot” that rolls inwards. When that foot rolls inwards, it causes the knee to also travel inwards. This drops the pelvis on that side. This causes the lumbar vertebra to tilt to the opposite side. Many muscles and ligaments are stressed because of these postural changes. This leads to pain in the back and the leg. Voilà!!! Kinetic chain dysfunction… not sciatica.
As you can see, this gets pretty complicated. I haven’t even listed all of the conditions that can cause low back pain with leg pain, but I’m guessing your head is already spinning. These different problems can look like true sciatica, but only a trained physician can correctly diagnose the real issue. Sometimes it is a serious problem that requires immediate medical attention. Sometimes it requires surgery. Sometimes surgical intervention will not fix anything. To compound the problem, studies have shown that MRIs are not as reliable as we once thought. Things like degenerative changes and disc herniations appear all the time in completely asymptomatic patients. The older we are, the more likely we are to have these findings on imaging, but that likelihood has very little association with the symptoms that we experience: it is simply a coincidental finding. Likewise, there are many people who experience what appears to be true sciatica upon clinical examination but have no findings on MRI or X-ray! For those of you who are interested in a reference, I can point you towards Rehabilitation of the Spine: A Practitioner’s Manual: Chapter 14 (this is considered the rehab bible by many physical medicine practitioners).
Despite all of the confusion and all of the controversy, there are established guidelines for treatment of sciatica. This is my synopsis:
-Treating sciatica with medicine like muscle relaxers, anti-inflammatories, and pain killers is an appropriate intervention on a preferably temporary basis, but it should be understood that medicine does not address the underlying biomechanical dysfunction. Though, it can help to ease the symptoms while the body heals. I myself sometimes refer patients to medical doctors when symptoms are severe enough to become a road block in my treatment programs. This helps them to get through care they otherwise would not be able to tolerate. In general, I like to communicate with the patient’s primary care physician anyways, so we can be on the same page.
-Sciatica that does not self-resolve in a few weeks should first be treated conservatively. This includes things like manipulation, physiotherapies, rehab, massage, and even needling. I also perform a few injections with neutraceutical medicines here in the office as I am licensed and certified to do so.
-If conservative therapy has absolutely no effect by two weeks, then I either change the plan, or possibly seek advanced imaging like X-ray or MRI. I do not allow patients to remain without progress in the clinic. If what we are doing doesn’t work, we either change the treatment plan, or I refer out.
-If conservative treatment is not sufficiently effective within several months, then advanced imaging is warranted if not previously obtained along with a possible referral for surgical consult. Though sometimes it is necessary for insurance purposes to first refer back to the patient’s primary care physician. This is another reason it is good to be in communication with the patient’s PCP.
-If I do refer out for surgery, the doctors usually only perform surgery after it is established that steroid injections or other less invasive medical intervention also fails.
-If surgery fails, then patients are typically referred to pain management clinics.
The healthcare community is well-aware of the opioid epidemic and nobody wants the final outcome to be simply mitigating symptoms with pain killers and other medications. The point is that conservative therapy should come first. If this fails, then more aggressive medical measures should be taken.
If you think you might have sciatica, please make an appointment today.