Understanding Sciatica from Causes to Treatment

Where does the term sciatica come from?

Since I entered the field of physical therapy, I have been asked about sciatica from numerous friends, family members and patients. Sciatica is also referred to as “lumbar radiculopathy” - lumbar meaning the lower back region, radicular meaning affected or related to the root of a spinal nerve and, lastly, pathos meaning suffering or disease. The questions I receive range from whether or not the individual is suffering from sciatica, understanding the cause, possible treatment options and, ultimately, whether it is serious.

The word sciatica originates from the Greek word “iskhiadikos”, indicating pain in the hip and has changed into the Latin form “sciaticus” and, later, “sciatica'' which is a disease characterized by pain in the sciatic nerve. For the French, the term “sciatique'' refers to a large nerve running from the pelvis to the thigh. Many patients and practitioners will casually refer to pain originating from the buttock region and radiating down to the foot as sciatica.

What is sciatica?

The term sciatica is merely a description and does not aid in the treatment or a true diagnosis. It is simply indicating the nerve - or rather bundle of nerves - has been adversely affected. In response to being injured or compromised, the nerve will send abnormal signals down the nerves’ various regions in the hip, thigh, lower leg and foot. This is experienced most times in one lower extremity, but can also be experienced in both lower extremities. The sciatic nerve root or roots are being “pinched”. The question is … what is pinching the nerve?

Unfortunately, the diagnosis of sciatica and many diagnoses simply describe symptoms but don't indicate with any degree of specificity what the "pain generator" is or the injured area. There are many examples in medicine that simply describe the mechanism or symptoms but don’t aid in treatment; those include knee pain or low back pain. Other obscure diagnoses found in medicine include being struck by a duck and sucked into a jet engine. (Fact check me if you must, but these are used in medical diagnosis jargon!) In the case of sciatica, we don't gain a tremendous amount of insight into the cause.

Anatomy of the sciatic nerve

The name of the condition is based on the largest nerve in the body, the sciatic nerve or lumbosacral nerve root, which starts in the lower lumbar spine from a collection of five nerve roots (L4, L5, S1, S2 and S3). This nerve complex provides nerve supply from the spinal cord to the skin, muscles in the hip, thigh and lower leg into the feet, and is close to 2cm in thickness at its largest point. These nerve roots are numbered based upon the vertebral level in which they exit the lumbar spine as depicted in the picture.

For example, the L4 nerve is exiting from the intervertebral foramina that is comprised of the upper L4 vertebrae and the lower L5 vertebrae. At this level, the lumbar vertebral disc is named based on the segment above and below vertebral segments. In this case, the L4-L5 disc is the one found close to the exiting L4 nerve. At times we do observe anomalies in where the nerve root originates and courses into the lower is rare but can be as between 4-6% in the lumbar spine (Eur Spine J. 2004 Mar; 13(2): 147–151).

If one of the nerve roots are injured (most commonly in the L4, L5 or S1), you may have loss or altered sensation in the lower extremity or weakness that may first appear as difficulty with balance or walking, sometimes developing weakness in the shin resulting in foot drop. When a person develops “drop foot” they have poor control of their foot as they make heel strike when walking, which may be accompanied by a "slapping" sound in severe cases. If you are unsure, an immediate call to a surgeon is required, especially if the weakness or balance problems are getting rapidly worse over a 24-48 hour period of time.

What does a person experience with sciatica?

Often, but not always, they may have lower back, leg and foot pain. They may experience neurological changes consisting of paresthesias, pain or motor deficits. The motor deficits or weakness may be evident while walking, and you may have general feelings of being “off balance'' or have experienced recent falls in serious cases.

Many positions of extending sitting and forward leaning can increase or temporarily worsen symptoms with sciatica. In addition, movements at the lumbar spine that rotate and flex (especially when combined) can increase and delay the recovery. Examples of these movements are: putting on your socks (especially in the morning), reaching for an item in the passenger seat while driving, and getting out of bed. Activities that may increase intrathoracic pressure, like sneezing, coughing, laughing, and bracing for lifting, can exacerbate in a person with a diagnosis of sciatica.

What are the causes of sciatica?

Some of the common causes of sciatica include:

What is a “red flag”?

A red flag is a sign that you need to go to the emergency room or see a doctor immediately. If you experience any of the following, you must get an evaluation by a medical doctor right away:

If you have any of these conditions, you should seek a professional consultation because a timely evaluation may affect if and how quickly you recover. In cases of loss of strength or bowel and bladder dysfunction, it can be permanent if not addressed in a timely manner.

https://youtu.be/oSluUbgxCZ0

What is “good” or “bad pain” when dealing with sciatica?

A general rule in guiding practitioners and patients is centralization or peripheralization. When we provide exercises to the patient, we discuss whether the movement of pain closer to the lower back in the case of centralization is typically a “good” sign. When symptoms move further away, this is termed peripheralization and considered a “bad” sign. When performing specific exercises after a McKenzie physical therapy evaluation and when performing activities during the day, we use this as a guide to aid in the patient’s recovery. Follow this link to more information on the McKenzie method in understanding what is “good” or “bad’ pain: https://apexorthopedicnj.com/back-pain-good/

Understanding different types of pinched nerves or peripheral nerve injury

Often, physical therapists, chiropractors and physicians will provide a diagnosis of a pinched nerve. There are varying degrees of nerve damage that can determine if and how long a nerve may take to heal. The standard answer for nerve healing times is 1mm a day, which gives a general timeframe.

In 1943, a physician named Seddon described 3 types of nerve injury from mild to severe:

Neuropraxia (mild) - In this type of injury, the recovery can range from days to weeks. Patients may complain of sensory changes from “burning” and “tingling” originating from the area where the nerve is compressed from a possible disc herniation or a hamstring strain resulting from scar tissue forming around the nerve. int of compression. In the case of sciatica, this frequently is the result of a lumbar disc herniation, bone spur or inflammation in the lower lumbar spine region. Often, healing will occur with time and controlling inflammation and avoidance of activities that may delay recovery. Examples of this, in the case of sciatica, is aggressive hamstring stretching, extended sitting or driving and doing activities that consistently spike the pain levels for the following 24-48 hours afterwards. At this time, surgery is not necessary, but injections to reduce inflammation or medications may be indicated in the form of an oral steroid Methylprednisolone, also known as a Medrol pack.

In the case of lumbar epidural injection at the appropriate level of the lumbar spine often an anesthetic of Lidocaine (AKA Xylocaine) lasting a couple of hours or Bupivacaine (AKA Marcaine) which is longer acting. Often, the anesthetic medications are accompanied by Cortisone which is a heavy duty anti-inflammatory medication to reduce the swelling, which can alter the nerve’s ability to conduct a normal signal to the skin, muscles, ligaments, etc. In some cases, a narcotic is also added to increase the anesthetic qualities with the cortisone. All nerve conduction studies of EMGs are normal when testing the affected nerves.

Axonotmesis (moderate) - In the early stages of the onset of the nerve injury, the conduction studies show no nerve conduction distal to the compression site during EMG studies. After 2-3 weeks, abnormal findings are noted in injured nerves in the form of fibrillation potentials and sharp waves. The potential for normal healing over time is still possible but may require surgery.

Neurotmesis (severe) - In this case, the nerve fiber is completely severed and the nerve conduction is completely absent distal to the compression site. Both sensory, motor and autonomic function is completely disrupted requiring surgical intervention.

Do you need an Xray or MRI when you have sciatica?

If you have just started experiencing sciatica without any of the red flags described earlier, it is not recommended to immediately get an xray and/or MRI. If you get an MRI before enough time elapses, at around 6-8 weeks, you can actually have a poorer outcome. The reason this occurs is that most MRI scans, especially with patients over 50 years of age, demonstrate normal age related changes of degenerative discs, herniated discs, and arthritis in the lumbar spine. Once the patient is informed about these findings, they can be apprehensive about movement and stop being as active and the prognosis is not as favorable. Statistically, the chance of spinal tumors or serious pathology is less than 1-2%, but often the patient advocates and the many physicians not trained in musculoskeletal conditions will order the MRI or xray partly out of concern over being considered negligent and a desire to take action of some sort. A mantra in the clinic is that severe pain doesn’t always equate to a serious pathology, similar to the pain experienced with a case of a pebble in your shoe. It really hurts and causes a limp, but the solution is not complicated and the pain generator in this case is not serious and the remedy is quite simple. Check out our YouTube video on red flags. Just follow this link: https://youtu.be/oSluUbgxCZ0

What makes sciatica worse or delays healing?

Many times when a person is in the process of healing, what we avoid or don’t do during recovery can often be more important than what we do as a remedy. It is essential to understand a patient's lifestyle and activities to ensure we don’t delay or obstruct the body's natural ability to heal. Hippocrates once stated, “We must turn to nature itself, to the observations of the body in health and in disease to learn the truth”. In the speed of medicine, the reliance on special tests and imaging via Xrays and MRIs, we often miss vital components of healing from sciatica or any other ailment. A person who shuts down and limits movements for fear of irritating their sciatica symptoms will delay recovery even when provided the necessary medications and exercise regimen. Just like if we pick a scab on our knuckle by bending the finger too early, we can undo the most well thought out treatment plan. Check out our tips on lower back pain and sciatic prevention: https://apexorthopedicnj.com/lower-back-pain-prevention-tips/

How long does it take for sciatica to get better?

Most cases of sciatica and lower back pain resolve in 3-5 days and can last as long as 6-8 weeks. The symptoms of sciatica can persist for years or reoccur after periods of being dormant and the patient lacking symptoms. Most times, if you have had sciatica, there is a high likelihood of recurrence and these episodes tend to become more severe in nature than the first episode.

How to do a self-test for sciatica

Below is a self-test to give you a general idea if you have sciatica, but is not meant to replace a good evaluation by a physical therapist or a physician.

Patients with diagnosed sciatica will report increased pain after extensive sitting or driving and less pain when walking or standing. When a patient coughs, sneezes and/or laughs, it can trigger these symptoms. In cases when walking and standing irritate the patient, the symptoms may be related to a form of lumbar stenosis or spondylosis.

When performing these self-tests, it should reproduce the same or similar pain in the buttock and lower extremity. Often, in sciatica, the symptoms can be “burning”, “tingling” or “numbness”.

The “slump test” is a neural tension test to see if the sciatic nerve is being pinched or compressed and abnormally sensitive. The test does not indicate what patho-anatomical structure is affected, just that the nerve is not conducting well. The analogy often used is of a garden hose that you step on or bend which reduces or stops the amount of water running through it. It is easy to perform in your home and the goal is to put tension on the sciatica nerve roots.

How do you do the slump test?

In cases where extending the knee doesn’t cause symptoms to begin, have the patient dorsiflex or bring the foot towards your head. If this reproduces the patient’s symptoms, then it is positive. Many times, patients may report “tightness” or “tension” and are unsure if this is a positive test. A good way to be sure you have a positive test is to perform the same test on the opposite side.

In addition to indicating if you have sciatica, it is also a good gauge if you are improving or healed to be performed a few weeks or days after symptoms started. Don’t continue to retest too frequently because, in certain cases, this will worsen your condition and irritate the nerve, therefore delaying the healing process.

How do we assess and treat sciatica?

We use the McKenzie method to evaluate and treat patients with sciatica. The McKenzie method is a systematic method of evaluating patients with musculoskeletal problems originating from the back, neck and upper and lower extremities. With this approach, a patient will discuss the history of the problem from onset of the current condition, past treatment, understanding activities and positions that alleviate or worsen their condition, use of medications, recent imaging from Xray, MRIs or nerve conduction, and past medical history.

Through this comprehensive history, we also make sure there are no indications of a serious problem like cancer, suspected fracture or infection. All these steps are taken prior to having the patient start the clinical examination, which includes checking range of motion, strength, reflexes, sensation, balance, special tests (i.e. slump test or straight leg raise test) and functional tasks like walking, squatting and managing steps. If the condition appears to be serious or certain red flags are present, you may not even start the examination and refer to the appropriate physician which may include spine surgeon, internist, or rheumatologist.

If it appears the patient’s musculoskeletal complaints are mechanical in origin, meaning related may benefit from a movement or position being restricted or strength deficit, we will move to the clinical examination. At the end of the evaluation we want to learn what positions or movements may reduce the patient's symptoms and improve their function. This will refer to a directional preference which may be lumbar extension in standing or a right side glide.

Once a movement or position is identified as helping the patient, we provide a home exercise plan on the first visit. On a case by case basis, the physical therapist may provide stretches similar to what the patient will do at home. We will discuss position, movements and activities that we want to avoid or modify until the patient starts to recover. Once the sciatica is under control we provide a plan to reintroduce patients to activities they are desiring to return to and how to avoid future episodes of sciatica through identifications of signs and symptoms in the early stages that are more easily self managed by the patient.

https://www.mckenzieinstituteusa.org/method-patients.cfm