Cervical radiculopathy refers to irritation or damage to a nerve in the neck. This typically occurs within the cervical spine, usually by impingement by a ruptured disc or a bone spur.
Symptoms can include the following:
Pain radiating from the neck into the arm. The location of the pain correlates with the exact nerve root, which correlates with the cervical level.
Numbness, tingling, pins and needles, or hypersensitivity, also radiating into the arm, again in a distribution correlating with the level.
Weakness in the muscles which the affected nerve or nerves innervate. For example, the C6 nerve innervates primarily the biceps, but the can be some overlap to the triceps or deltoid.
Natural History of Cervical Radiculopathy
This will depend a great deal on the cause. With a ruptured cervical disc, the onset of pain is sudden. Often the person will feel a pop while heavy lifting, with a fall, or other trauma. Pain, often burning or electrical in nature, will then develop over hours. This pain may peak over the first few days, and gradually subside over weeks. Interestingly, in many cases there is no precipitating trauma, and the person may wake up with the pain or it may develop during the day. In these cases, the disc likely was weakening over time, and finally ruptured in response to normal daily activities.
The mechanism of this pain response is an intense inflammatory response in the nerve at the site of compression. This results in a "short circuiting" of the nerve electrical potentials, causing the sensation of pain along the distribution of the nerve in the arm. The extent of the distribution may vary, from very proximal in the neck and upper arm, to all the way into the hand and fingers.
Eventually, the inflammatory response may subside on its own, leading to improvement in pain. This may happen spontaneously, even with continued pressure by the disc or bone spur (called osteophyte). This leaves the possibility that the nerve may be injured again by a sudden motion or tension, triggering another intense inflammatory response and possibly more damage.
If nerve impingement is caused by osteophytes, this compression has been building over time, and typically the pain has likely been building over time as well. The pain may wax and wane, and may be triggered by certain movements or position of the neck.
Weakness or numbness are a cause for concern, as these signs indicate some degree of dysfunction, or damage, to the nerve. In the case of weakness, the signals from the brain are simply not being properly transmitted across the injured portion of the nerve to get to the muscle. Numbness results from signals from the limb not being properly transmitted to the brain across the injured portion of the nerve. Therefore, weakness and numbness are red flags which demand more careful consideration and possibly a more aggressive approach to treatment. This is discussed further below.
Treatment of Cervical Radiculopathy
Initial treatment is directed at relieving pain and inflammation. After a focused examination by a specialist, an MRI of the cervical spine is usually recommended. Even if the pain is improving, the MRI will show the cause and help us to know what we're dealing with. This is especially helpful if there is sudden worsening in symptoms. The mainstay of medications is a nonsteroidal anti-inflammatory drug (NSAID), such as ibuprofen or naproxen. Yes, over the counter Advil or Motrin can be very helpful. Often a short course of steroids is given at the onset, the help kickstart the recovery. Sometimes opiates such as hydrocodone are needed for breakthrough pain, and these should be used sparingly and for a short period of time.
Cervical traction is a device that can be helpful in relieving pain from radiculopathy. The over-the-door string and sling devices have been replaced by devices that you pump with air and apply tension upward on the head and downward on the shoulders. This can provide effective, albeit usually temporary, relief. This can be difficult to get covered by insurance, and many people buy their own traction device online.
Physical therapy can have a role here, as it does in many other aspects of spinal dysfunction. One must be careful to avoid manipulation of the neck, however. Excessive motion or force on the neck may worsen the nerve inflammation, and may cause more disc herniation. Traction and massage can be helpful.
Spinal injections can also be helpful for cervical radiculopathy. This involves applying a medication, typically a steroid and also sometimes an anesthetic, into the spine next to the nerve. This can relieve the inflammation, but does not correct the underlying condition or relieve compression of the nerve. The effect is usually temporary. An injection should not be attempted if there is spinal stenosis with cord compression.
When Surgery is Recommended
Despite undergoing the above treatments, sometimes the pain does not improve and remains debilitating. If there is weakness or numbness, the situation becomes more urgent. The following criteria should prompt consideration of surgery:
- Pain which does not improve, or which keeps recurring, and is severe enough to interfere with daily living and quality of life.
- Weakness or numbness which is noticeable by the person or the doctor. This is an indication of nerve damage rather than just inflammation. Surgical decompression carries the best prognosis for improvement or recovery of strength and sensation.
- MRI which shows compression of the spinal cord in addition to the exiting nerve. This carries a high risk of spinal cord injury, with potentially serious and irreversible loss of function below the neck.
- Any evidence of cervical myelopathy. This refers to spinal cord dysfunction, in this case due to compression of the cord by disc or osteophyte. Signs and symptoms of cervical myelopathy include incoordination or weakness in the hands, a feeling of heaviness or "feeling dead" in the hands, heaviness or weakness in the legs, noted with climbing stairs or getting up from a chair. The doctor may find abnormal reflexes in the arms, hands, and feet. The presence of cervical myelopathy should prompt surgical decompression to avert further loss of function and possibly regain function.
Surgical Treatment of Cervical Radiculopathy
When the criteria above are met and surgery is indicated, several options are available. These consist of (1) cervical decompression and fusion, (2) cervical discectomy and artificial disc replacement, and (3) cervical foraminotomy. Let's look at each of these.
Cervical Decompression and Fusion
This is often called Anterior Cervical Decompression and Fusion, or ACDF. This is the time-tested, "traditional" surgery for relieving compression on the spinal cord or nerves, and is very effective for this condition. First, the surgeon removes the disc, including the fragments causing impingement, until a complete decompression is achieved. Then, a graft is inserted into the disc space to restore the normal disc space height and spinal alignment. This graft may consist of the patient's own bone from their hip, donor bone from a cadaver, or artificial materials such as PEEK (a synthetic similar to plastic) or titatnium. Finally, screws or a plate and screws are usually used to stabilize the area. Over time, bone will grow across this area, resulting in a solid fusion.
Below, an X-ray showing a 2-level cervical fusion. After discectomy and decompression, titanium cages are placed into the disc space to restore disc space height and proper alignment. A titanium plate and screws secures the construct.
One potential downside of this surgery is that the fusion removes a motion segment. That is, of the 8 motion segments created by the 7 cervical vertebrae moving on each other, 1 or more of those segments becomes immobilized. This is thought to produce additional strain at the levels above and below, possibly accelerating the degenerative process. This is known as adjacent segement degeneration.
Cervical Discectomy and Artificial Disc Replacement
A newer technology, this allows preservation of the motion at the diseased level or levels, thereby preserving the overall biomechanics of the cervical spine and reducing or eliminating adjacent segment degeneration.
Several models are currently FDA approved and being used. Clinical data up to 10 years has suggested superiority of 1 or 2 level disc replacement compared to fusion. A truly definitive body of evidence, as well as long term outcomes, will require more time.
Below, X-ray showing a 2-level disc replacement with Zimmer Biomet Mobi-C devices.
Below, X-ray showing a 2-level disc replacement with Medtronic Prestige device.
Posterior Cervical Foraminotomy
In some cases, the pressure on 1 or more nerve roots is caused primarily by bony osteophytes or facet overgrowth (part of a process called arthropathy). In these cases a foraminotomy may provide the necessary nerve decompression. This procedure involves an incision in the back of the neck, and a small window-like opening is drilled out over the nerve root.
The advantages of this procedure over the anterior procedures described above is that a discectomy is not performed, no hardware is implanted, and the biomechanics of the spine are minimally affected. This procedure does not provide adequate decompression, however, if there is disc rupture or large bone spurs. Also, in cases of degeneration of the disc and facet joints, fusion may be the best option to provide relief of neck pain.
The modern treatment of cervical radiculopathy involves a multimodality approach, beginning with an accurate and detailed diagnosis based on examination and imaging. Nonsurgical therapies, and time, are often enough for a permanent resolution.
In the event that surgery is required for treatment of cervical spinal cord or nerve compression, several options exist. The patient's individual condition must be evaluated carefully to arrive at the optimal surgical approach. A "cookie cutter" approach is not appropriate. With the right surgical treatment, outcomes can be excellent, with the patient returning to a pain-free and active lifestyle.