CERVICAL DISC DISEASE AND CERVICAL DEGENERATIVE (OSTEO) ARTHRITIS - PART 1

(A Patient Information Service)

The disc acts, in part, like a shock absorber between each vertebral body. The center of the disc (the Nucleus Pulposus) is a soft, gel-like substance that is held in place by a strong, dense multi-layered, multi- ringed capsule, the Annulus Fibrosus (Figure 3). The disc is attached to each adjacent vertebra and is surrounded by a series of very tough ligaments that also connect each vertebra in the Spinal Column. During the natural daily activities of movement and weight bearing, there is a very slow progressive "wear and tear" process in which the soft disc center (Nucleus Pulposus) becomes less rubbery and more brittle. It slowly becomes more like crab meat in its consistency during our 30th through 50th years of life. Beyond these years, the discs wear down; the center shrivels and dries rendering it less efficient as a shock absorber. This process is, to some degree, similar to what happens to "original equipment shock absorbers" on the family car. Unfortunately there are no "real replacement" discs available at this time although experimental products are being developed. The first artificial mechanical joint became available in mid-July 2007 in the manner of the "Prestige"® Cervical Arthroplasty Device (manufactured by Medtronic Sofamor-Danek). This is a stainless steel "ball and trough" design that is approved for implantation at one cervical level (from C3 to C7). There are over a dozen other synthetic bio-plastic/metal Arthroplasty devices designed by other companies currently under clinical investigation. Additional information is available in Cervical Spine Information-Part 2 and/or our website.

During the time that the discs are undergoing these degenerative changes, the Facet Joints (located posteriorly [in the back] and on either side of each vertebra) which assist in connecting one vertebra to the next, are also subjected to increased stresses. These joints are critical for normal neck movement. Each Facet Joint has, as "original equipment", a glistening smooth lining (Synovium) and a small amount of "joint fluid" (Synovial Fluid) that helps to facilitate motion of these joints. The neck motion of everyday activities inevitably results in a certain amount of "wear and tear" on these joints. As the disc becomes less efficient as a shock absorber, more stress is placed on the Facet Joints. The entire process involving the "wear and tear" on the joints, and their response to this "trauma", is called Degenerative Osteoarthritis (osteo=bone; arthritis=inflammatory change in the joints). As part of this process, the glistening, smooth joint surfaces slowly wear down and the joint's lubricating fluid is slowly "used up." The joints, and the bone near them, make every attempt to protect themselves against this wearing down. This response takes the form of laying down new, dense bone in and around the joint. This new hard bone is the body's way to try to prevent the bones from wearing away. In some cases, this new bone forms "spurs" which can compress the neural elements in the Foramen and/or Spinal Canal.

Some people seem to have a tendency towards developing more degenerative disc disease, along with its associated osteoarthritis, faster than other people. In some cases, it appears to be related to adolescent and adulthood sports activities, repetitive heavy lifting or previous neck injuries such as "whiplash" (as occur in rear-end motor vehicle accidents) or repetitive blows to the top of the head (as occurs in football players and the cliff divers in Acapulco, Mexico). Frequently, no causative agent or experience can be identified. It is important to recognize that many people can have far-advanced degenerative disc disease, osteoarthritis with large bone spurs and have absolutely no history of injuries of any sort. In addition, these same individuals may never have experienced any significant neck discomfort despite the fact that the degenerative process is so advanced. It is frequently a shock to these patients when they are made aware, for the first time, of the advanced state of their arthritis after an x-ray has been taken. The x-ray may have been taken when the patient complains of severe and relentless neck pain after a fairly trivial neck injury. These patients frequently express their disbelief upon hearing that their disease has actually been present for many years. The opposite extreme to this scenario occurs in younger patients (20's and 30's) who experience frequent (and occasionally severe) neck pain from these joints, and in whom x-ray studies are entirely normal.

Pain is the most frequent symptom that brings the patient with a neck problem to their physician. The pain may originate from any of the structures that we have reviewed so far, or from some other anatomical areas such as the Nerve Roots (or their coverings) which leave the Spinal Cord at each cervical level. (See figures 4, 5, and 6.) The experience of a painful stiff neck is familiar to most of us. The "stiffness" is usually the result of muscle spasm or tightness in the powerful paravertebral muscles that lie on either side in the back of the neck. This is the body's way to attempt to immobilize the joints that are injured. When the paravertebral muscles contract, they reduce the amount of movement that the joints would ordinarily have. However, the muscle spasm frequently is quite painful in and of itself. Some patients notice that their muscles feel like "knots." This is the result of increased contraction of some of the muscle fibers.

Many patients also experience pain in the back of the skull (suboccipital region), which can be quite severe. It occurs with more severe contraction of these paravertebral muscles and is due to the muscle pulling on its insertion at the base of the skull which is covered by a thin layer (called "Periosteum") that is rich in pain fibres.

A local application of heat (heating pad, moist or dry heat) or ice (with careful attention not to injure the skin with these temperatures) frequently offers significant relief from the muscle spasm. Massage (with or without liniment, balms, salves, or oils) also may offer welcome relief from muscle spasm. In many cases the problem is only with the muscle (such as a muscle strain), and these measures provide satisfactory relief. However, it is prudent to remember that the muscle spasm may be an attempt by the body to protect us from further injury relating to a more important underlying difficulty. It then becomes increasingly important to more precisely identify the underlying pathology. Any persistent or recurring, severe neck pain deserves a more thorough evaluation by your physician.

A neck "crick" is another common complaint. This symptom complex is most frequently experienced upon awakening in the morning. You usually know immediately that you "slept the wrong way." Stiffness and soreness are the hallmarks of this problem. It is the result of excessive stress on one or more Facet Joints on one side of the neck most likely related to lying in a peculiar position for some time. For some people, this is a frequent and repetitive annoyance. It may or may not be the result of more serious or advanced "degenerative arthritis." Common sense usually tells these patients to experiment with different sizes and shapes of pillows as well as body sleeping positions (or even mattresses) in order to avoid this recurring discomfort.

Cervical Collars

Medications

One of the more serious disorders of the cervical spine is a Herniated Disc. The "herniated disc" is, in medical terminology, a "Herniated Nucleus Pulposus (HNP)." It is commonly called a "slipped or bulging disc," "ruptured disc," "misplaced” or "displaced" disc — to name a few. In this situation the shock-absorbing, softer center of the disc (Nucleus Pulposus) has pushed against, stretched or torn its way through the confining multiple layers of the capsule (Annulus Fibrosis). The Posterior Longitudinal Ligament, which assists the Annulus Fibrosus to hold the disc in place, is also stretched and damaged but remains intact.

The Spinal Cord is well protected as it lies inside the bony central Spinal Canal formed by each vertebra lying one on top of the other in the spinal column. At each vertebral level, one pair of Nerve Roots leaves the Spinal Cord through narrow bone openings (the Neural Foramen) on either side of the bony Spinal Canal. When the herniated disc pushes backwards it may compress the Nerve Root and/or Spinal Cord that lie directly behind it within the bone ring of the Spinal Canal. The Nerve Root can be damaged as it is pinched or pressed against the bone of the Spinal Canal. The nerve frequently responds to this pressure by developing Nerve Root swelling which results in more Nerve Root compression in the Neural Foramen. This increased pressure reduces the blood supply to the Nerve Root producing more damage to the Nerve Root and more swelling. A vicious cycle is established which could result in serious (possibly irreparable) injury to the Nerve Root.

A herniated disc is very uncommon in young people. It is more frequent in the third and fourth decades. Oftentimes some form of trauma can be identified as the cause the problem. Neck injuries from automobile accidents or lifting injuries are familiar to most physicians who treat these ailments. Another frequent experience is the herniation of a disc in the morning upon awakening. Each disc takes in some water (from body fluids) at night when lying down rendering the disc larger and under more pressure. In the morning, probably when turning suddenly in bed, there may be considerably more pressure exerted upon the disc. The pain is usually described as deep in the neck and made worse by certain neck movements. Many patients experience pain between the shoulder blades as well as in a shoulder and/or arm. Even in milder forms of disc herniation, the pain can be relentless with periods of relative worsening. Medical treatment will probably become necessary for most patients with a herniated disc. It is necessary to caution that not all neck pains are related to a herniated disc or joint problems. An accurate diagnosis by a skilled physician will help to focus on the precise problem for which specific treatment is appropriate.

Most people who suffer a herniated disc recover without any surgical treatment. The object of any treatment is to have the "herniated" portion of the disc return to its proper place and thus relieve the pressure on the Nerve Root. The blood supply to the Nerve Root will improve once the swelling diminishes. It is equally important to try to allow the damaged disc capsule and ligaments to heal.

Spinal Manipulation

Cervical Traction

Even if the herniated disc "slips" back into place and the pain, tingling, numbness and weakness are completely relieved, there remains an injured, weakened disc capsule and ligament. These damaged structures take MONTHS TO HEAL (if ever). There are NO MEDICATIONS and NO EXERCISES which will improve these structures. Exercise can only stretch and stress the already damaged ligaments. The only treatment that we would recommend is neck immobilization. This usually means wearing a soft collar at night and a firm collar in the daytime. It may be too uncomfortable to wear the firm collar when lying down. Many patients cannot accept the requirement to wear an immobilizing collar once they feel better. Hopefully with a better understanding of the anatomy and function of these structures, they will make the appropriate choices to permit their tissues time to heal. If the disc capsule and ligament fail to heal well, then one can understand how much more easily a recurrence of the problem can occur at some later date. Sometimes the initial injury to the disc capsule and ligament are sufficiently severe that they can never satisfactorily recover, and the patient will eventually experience a recurrence of the "herniation". Only the passage of time (which may turn out to be many years later) will tell. There are no reliable x-rays or other tests to assess the state of these ligaments.

There are several questions that are frequently asked about cervical traction such as: "How much weight? How long do I use it? What position is best? Who should supervise it?" We strongly urge that cervical traction only be used under the supervision of your physician. Although it is relatively safe, it could cause some damage if improperly applied.

Traction can be applied to the cervical spine while the patient is sitting or lying down. One often prescribed system can fit on a doorjamb at home or even at work at your desk. There are expensive pneumatic or cable-driven devices that are not necessarily better than the less expensive, passive varieties. The best traction device is one which allows the patient to lie down and is adjustable for height. When you are lying down (particularly when asleep), you are more likely to be relaxed which means that the strong neck muscles are not counteracting the pull of the traction and the traction does not have to overcome the same gravitational force of the skull as when you are sitting. When recumbent, seven to eight pounds of traction is all that is required. More weight is not better and will cause Temporo-mandibular Joint (TMJ or jaw joint) pain. A "halter" device fits under the chin and attaches to the traction apparatus. In the sitting position, you will need a little more weight, sometimes up to 14 pounds. The angle at which the traction pulls upon the neck should be as close to a "neutral" (straight relative to the spine) position as possible. The traction device should be adjustable to allow for changes in the angle of pulling.

There is one firm rule about using traction. IF IT HURTS, DON'T DO IT. Traction should not make the pain or the symptoms (such as tingling) worse. If it does, stop using it and talk with your physician.

The amount of time spent in traction depends on your condition and the stage of your treatment and recovery. In the acute (early) stages of treatment for a herniated disc, it is best to use the traction for as many hours of the day and night as you can tolerate it. In those patients with advanced weakness in the arm or hand and/or those with unrelieved excruciating pain, your physician may recommend hospitalization for several days where more powerful sedatives, muscle relaxants and pain relievers can be used. As a general rule, we are able to improve most patients with a herniated cervical disc within five days. If the pain or neurological problems are not improved within this time, the problem deserves further evaluation. In the event that there is improvement, further traction at home for seven to 14 days may be necessary. After this, depending on the patient's condition and work requirements, traction can be used intermittently for another few weeks or months.

We have mainly been discussing the medical management for herniated cervical disc; however, the treatments are also appropriate for cervical degenerative arthritis. There are some fundamental differences, in the long-term aspects, between patients with a herniated disc and those with degenerative arthritis (bone spurs). In patients with Nerve Root injuries from a bone spur, the bone spur has been present for years. The acute injury to the nerve is usually the result of some relatively sudden movement or a trivial injury in the face of long standing and relentless pressure on the nerve as it lies against the bone spur in the Neural Foramen (the bone window on the side of the spinal column through which the Nerve Root exits from the Spinal Cord). The compression injury produces Nerve Root swelling inside the Neural Foramen which is already made smaller by the hard bone spurs. Cervical traction can allow the cervical vertebrae to be "stretched apart" for a very short distance. Frequently this is sufficient to allow the Nerve Root enough room so that the swelling can be reduced. Once again, the length of time in the traction apparatus and the degree of vigor with which traction and medical treatment (muscle relaxants, pain relievers and oral steroids) is pursued depends on the severity of the neurological injury and the degree of pain. Cervical Spine manipulation is absolutely inappropriate in the case of nerve injury by a bone spur. The bone spur is not going to be changed by any form of manipulation or medicine. Manipulation of the spine can result in significant injury to the Cervical Nerve Roots or the Spinal Cord in these patients. For those patients who have a serious nerve injury, hospitalization may become appropriate for a trial of cervical traction. If the neurological condition improves then this treatment can be continued; nevertheless, the bone spur(s), as part of a progressive "degenerative" process, will not go away. This does not mean that surgical removal is necessary in the majority of these patients or that surgical treatment is inevitable. It does mean that some reasonable care, caution, and good common sense will be necessary in order to try to avoid repetitive nerve injury.

"Extruded Disc" - A Unique & Important Condition

An Extruded Disc can and frequently does occur in the presence of significant bone spur formation, although one is in no way dependent upon the other. However, when the two co-exist there is an added dimension of neural element compression. The bone spur has already been present for some time. It may or may not have produced symptoms in the previous years. The additional insult to the nerve by a herniated disc into a previously narrowed Neural Foramen (narrowed by the bone spur) or Spinal Canal may result in a more severe injury to the Nerve Root and/or Spinal Cord. While early preliminary medical treatment is important in an attempt to limit the extent of the Neurological injury, surgical correction is usually required to effectively repair this condition.

Steroids – A Useful Adjunct to Treatment

Other "Injection" Methods

"Facet Rhizotomy" is another "needle" procedure. In this instance an electrical current is placed through a special needle in an attempt to permanently destroy the small sensory nerve that may supply a degenerative joint. This technique, like any Facet "injection", will have no effect on the underlying degenerative process that affects the joint.

"Chemonucleolysis", a technique that had become popular in the past, involves the injection of an enzyme into the disc to attempt to "digest" the disc. It is absolutely illegal (in the USA) to use this treatment in the cervical spine. If the medication (enzyme) leaks into the area of the Spinal Cord or Nerve Root, there could be a disaster since the enzyme can also "digest" the Spinal Cord or Nerve Root.

Diagnostic Neuroimaging

In many cases, the physician will recommend a Cervical Spine X-ray examination. Several viewing angles are a routine part of the evaluation. We prefer front, side (lateral) as well as left and right oblique views in order to properly determine the extent of bone involvement for each of the cervical vertebrae. All the cervical vertebrae are seen on each of these four (4) views. (A fifth view may be taken to better evaluate the first cervical vertebra.) Although the disc (or its herniation) CANNOT BE SEEN by these x-rays, some inference can be made. In the case of degenerative disc disease, the involved disc space(s) will be narrower in height when compared to the normal discs. Even though a narrowed disc space implies degenerative disc disease, it certainly does not mean that this, necessarily, is either the source of the pain or the site of the ruptured disc in any particular patient. The involvement of the various joints of the cervical spine at each level with degenerative arthritis and the degree of bone spur formation can be evaluated by these "plain" x-rays if they are of good quality.

The "Uncovertebral Joints" are important anatomical structures of the cervical Spine that lie bilaterally (both sides) on the antero-lateral (far front) side of each vertebral body immediately adjacent to the Neural Foramen. Degenerative arthritic changes in these joints results in bone spur formation that can cause severe Nerve Root compression at the opening to and throughout the Neural Foramen. Uncovertebral Joint "hypertrophy" (bone spur formation) is one of the most common causes of Foramenal stenosis and Nerve Root injury. Plain x-rays can give some information about this unique anatomy; however, CT scan is the most accurate method to evaluate these structures.

As often as not, we have found that we cannot correlate the degree of arthritis at any particular level with the pain. The only clinical way to correlate the problems, at this stage, is to compare the neurological findings (from the physical examination by your doctor) with the findings on x-ray or other neuroimaging (MRI and/or CT scans) studies. If your pattern of neurological involvement suggests a particular Nerve Root and the x-ray shows a significant change at that same level, then it is more likely that this level is the source of the problem. Many patients have bone spurs at more than one level. The fact that they are there does not mean that they are now (or will ever be) the source of any difficulty.

MRI (Magnetic Resonance Imaging) is another technologically advanced examination that can be used for spine problems. For the majority of these patients MRI is the best initial screening neuroimaging technique. It is well suited for "imaging" the Spinal Cord and frequently gives useful information about the other structures such as the discs, spinal canal diameter and the Cerebrospinal Fluid (CSF) space around the Spinal Cord. It provides less information about the bone structure.

CT Scan (Computed Tomography also known as "CAT" - Computerized Axial Tomogram) is another x-ray examination that can be of considerable help in defining the anatomy of a cervical problem. This test is the most effective method for "imaging" the bone and joint anatomy or any other structures that have developed a bony or calcified component (such as the pathologically calcified Posterior Longitudinal Ligament or some Spinal Cord tumors.) It is not reliable in evaluating the disc or Spinal Cord.

The amount of useful information that is gained depends upon a number of factors including the kind of machine that is used. The costs for using newer MRI and CT technology are not much more than those for the older machines. The quality of the information can be very different. Even the most modern MRI or CT devices can fail to give the appropriate information unless they are well supervised. The optimal situation for the best results is to have the test done with modern technology and supervised by an experienced neuroradiologist who should also have the responsibility to interpret the test results.

Both CT and MRI scans have permitted major advances in our diagnostic accuracy and have almost no significant risk to the patient. Neither of these tests would be part of a routine evaluation for a patient with relatively minor neck pain. Most neck pain patients will have an accurate diagnosis made by their physician and will respond to treatment. In the event that your physician suspects a more serious problem such as a nerve injury which doesn't improve, Spinal Cord compression or a congenital abnormality (a condition that you are born with which may not manifest itself until later in life), then these tests may become necessary.

A Myelogram is another specialized x-ray test. When combined with a CT scan, it is usually considered to be the "Gold Standard" as the most accurate neuroimaging study for evaluating the conditions of herniated cervical discs and degenerative arthritis of the cervical spine for which surgery will be appropriate. This test, although very accurate and reliable (if done under optimum circumstances), is more uncomfortable than the others mentioned and carries with it some small risk. We do not recommend this examination unless the patient is clearly a candidate for an operation and the other non-invasive neuroimaging studies have failed to fully elucidate the extent of the structural anatomical condition. In the event that a myelogram becomes appropriate, it is usually carried out in anticipation that surgery is to be done. It is designed to more precisely pinpoint the anatomical extent of the structural problem as well as to evaluate the circumstances of the other Cervical Vertebrae together with the anatomy of the inside of the Spinal Canal. Patients with significant multi-level degenerative arthritis, particularly those with Spinal Canal and/or Foramenal stenosis and/or calcified Posterior Longitudinal Ligament, are among those who may benefit as a result of the critical information derived from this examination.

The Neuroradiologist who will conduct the myelogram will discuss the details of this test with the patient and will review the technique, the small risk and any other additional details that involve that particular patient. The Neuroradiologist will be happy to answer any questions pertaining to any of these investigations.

Each step of the Myelogram is conducted under x-ray (fluoroscopic) control. After the skin insertion site and underlying tissues are infiltrated with a local anaesthetic, a special needle is inserted into the Spinal Canal, through the Dura Mater (the thick tissue layer overlying the Spinal Cord) and into the subarachnoid space where the Cerebrospinal Fluid (CSF) circulates around the Spinal Cord. Once accurate placement of the needle has been confirmed, a special dye substance is injected into the subarachnoid space. Multiple x-rays are taken, including special views from various angles. Immediately thereafter the patient is transported to the CT scan for additional images. It is these images that provide the extraordinary bone detail of the spine that can be critically important in the thorough pre-operative technical surgical planning process required for satisfactory and permanent treatment of the unique anatomical circumstances for any particular patient.

Discogram & Disco CAT Scan

Electromyography and Nerve Conduction Velocity (EMG NCV)

It is important to recognize that not all of these tests are either necessary or appropriate for every patient who has these problems. Your physician will help to guide you towards the ones that best suit your medical condition.

In the event that these non-operative ("Conservative") treatments fail, then surgical alternatives may become appropriate. In most cases surgical intervention is not appropriate until conservative, nonsurgical treatments have failed (unless there is Spinal Cord injury and/or very severe Spinal Canal narrowing due to large bone spurs or significant Spinal Cord compression due to a large herniated disc). In our view, cervical spine operations are rarely appropriate for patients with neck and/or arm pain in the absence of significant neurological deficits or major Spinal Canal narrowing. (Please see Cervical Spine Information-Part 2 for further details of the "Indications for Cervical Spine Surgery".)

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This page last edited on 2/20