Cervical Degenerative Disk Disease
Degeneration means wear and tear, usually due to aging process. This wear and tear can involve any joint of the body, which also includes a spine in the cervical spine or the neck.
This aging process can set in at a variable speed in different individuals depending on individual characteristics, genetics, modifiable factors like injuries, smoking, systemic diseases among others. The degeneration in the cervical spine can involve either of the three joints namely the two facet joint and the one disc space.
All the three are usually involved simultaneously, but it is the degeneration of the disc which is more often symptomatic and needs treatment. The degeneration of the disc can be accelerated due to injuries in the form of a single accident or exposure to microtrauma over a period of time. Systemic diseases like rheumatoid arthritis can also accelerate the process of degeneration.
The degenerative disc disease of the cervical spine usually involves the most mobile segment that is the C5-C6 followed by C6-C7 and C4-C5 disc levels. The degeneration causes decreased water content of the disc or desiccation which leads to tears in the outer ring or the annulus fibrosus.
These tear allow the herniation of the central nucleus pulposus to the periphery. When these herniations are along the back of the disc, they can compress over the spinal cord or the nerve root leading to variable symptoms and presentation
PRESENTATION OF PATIENTS WITH CERVICAL DISC DEGENERATIVE DISEASE
Vast majority of patients who have degenerative cervical disc disease are asymptomatic and remain asymptomatic throughout their life. A small percentage of patients present with symptoms of neck pain or that of compression of the nerve root on one side presenting with symptoms of radicular pain going down the specific dermatome in the arm, tingling, numbness, and rarely weakness of the muscles innervated by that specific nerve root. These radicular symptoms are caused by the disc herniation onto the side of the back of the disc thus compressing the nerve root. Rarely patients may have disc herniation to the back in midline, which can compress the spinal cord leading to symptoms in one or all four extremities along with tingling, numbness, radicular pain, electric shock-like sensations, involvement of bowel or bladder and gait abnormalities. These patients may also have hand dexterity problems in the form of dropping things, weakness of the grip strength, change in handwriting among others. Patients may have disc degenerative disease of multiple levels causing multilevel cervical stenosis. There may also be hypertrophy and calcification of the ligament on the back of the spinal cord contributing to the stenosis. Patients with congenital cervical stenosis may be predisposed to such disease. These patients may present with acute deterioration of their neurological symptoms following trivial trauma or whiplash type injury in the neck. Examination of patients with radicular pain may show weakness of specific muscles and dulling of reflexes while in patients with compression of the spinal cord may show increased tone of the muscles, weakness, decreased sensation as well as hyperreflexia.
WARNING SIGNS OR RED FLAGS IN CERVICAL DEGENERATIVE DISC DISEASE
The patients who have back or neck pain with any of these following conditions should seek medical attention as soon as possible.
1. Cancer, neoplasia or malignancy.
2. Unexplained weight loss of more than 10 pounds in the last 6 months.
3. Immunocompromised comorbidities like on chemo or radiotherapy or having disease like HIV or AIDS or being on prolonged corticosteroid therapy.
4. IV drug users.
5. Urinary tract infection.
6. Fever of more than 100 degrees centigrade.
7. Significant trauma from a fall or accident.
8. Bowel or bladder involvement in the form of incontinence or retention.
9. Weakness in the major joint of arm or leg.
MANAGEMENT OF CERVICAL DEGENERATIVE DISC DISEASE
Most people with cervical degenerative disc disease are asymptomatic and remain asymptomatic for their life.
These patients may never visit a physician for the complaints with regard to the cervical degenerative disc disease. Some of these patients may have neck x-rays for unrelated reasons and may be found to have degenerative disc disease. Such patients do not need any active treatment. Patients who present with occasional neck pain can also be treated with exercises and occasional medications.
Patients with symptoms of radiculopathy are usually treated conservatively for 4 to 6 weeks with excellent chances of resolution of symptoms. These patients are usually treated with physical therapy and medications. Neck collar may be used for a short period. If the patient fails conservative treatment, an MRI is usually performed to confirm the level of disease and collaborate with clinical findings.
These patients are offered surgical management to relieve them of the pain. Surgical management for cervical degenerative disc disease with compression of the nerve root or the cord from the front is usually in the form of cervical fusion or disc replacement done from the front. Another option include microscopic posterior foraminotomy, done from the back, which is a motion sparring (non-fusion) minimal invasive surgery.
Patients who have compression of the spinal cord from the back may need surgery from the back to relieve the pressure. Surgery from the back may involve removing of the bony elements from the back, relieving of the pressure and cervical fusion over multiple levels (Laminectomy and Fusion) or opening of the bony elements of the back using many plates to increase the space available for the spina (Laminoplasty).
A decision between varied surgical procedure is usually made on patient characteristics and presentation. Patients with spinal cord compression may need an emergent treatment plan especially in presence of deteriorating neurological status or acute onset to contain the neurological damage as well as allow possible recovery.
The images above show ACDF (anterior cervical decompression and fusion) plate and instruments used to fuse the cervical vertebrae from the front of the neck. The surgery helps to decompress the spinal nerves/spinal cord and prevent movement between the segments to alleviate the symptoms and achieve stability.
PROGNOSIS AND RECOVERY FROM CERVICAL DISC DEGENERATIVE DISEASE
Patients who undergo conservative treatment usually have excellent chance of complete recovery of their symptoms over a span of 4 to 6 weeks. Patients who fail conservative treatment may need surgical management for resolution of symptoms.
Patients who undergo surgical management for radicular pain in the form of cervical discectomy and fusion, disc arthroplasty or posterior foraminotomy usually have near complete recovery along with resolution of symptoms.
Patients who have spinal cord compression may have guarded prognosis. The recovery is inversely proportional to the deterioration of neurological deficit prior to surgery. Though the surgery may optimize and allow good environment for spinal cord to recover, it may take many months to years for a partial or a near complete recovery.
Occasionally despite all measures, patient may not get any recovery. Patients with spinal cord compression have a prolonged rehabilitation period and are at risk for multiple other problems including urinary tract infection, lung infection, deep vein thrombosis, pulmonary embolism, aspiration pneumonia, respiratory depression, death among others.
RISKS AND COMPLICATIONS OF CERVICAL SPINE SURGERY
As for all surgeries there are certain but rare risks for anesthesia including cardiac arrest, stroke, paralysis, and rarely death.
Risks of Cervical spine surgery may include though not limited to:
• Hematoma or hemorrhage
• Damage to the carotid or vertebral artery which may result in a stroke or excessive bleeding, even death
• Damage to the nerve in the neck resulting in hoarseness or swallowing difficulties
• Damage to the food or wind pipe
• Damage to the dura, resulting in a cerebrospinal fluid leak
• Failure, loosening or pull out of the graft, cage, implant or plate
• Wound infection
• Failure of fusion to happen
• Damage to the spinal cord or nerve root(s) resulting in new onset or deterioration of preexisting pain, weakness, paralysis, loss of sensation, loss of bowel or bladder function, impaired sexual function, etc., which may or may not recover.
• A few of these conditions may warrant repeat surgery
Certain patient population is at a higher risk for complication which include but are not limited to:
• Obstructive sleep apnea
• High blood pressure
• Other medical conditions involving your heart, lungs or kidneys
• Medications, such as aspirin, that can increase bleeding
• History of heavy alcohol use
• Drug allergies
• History of adverse reactions to anesthesia
WHO IS A GOOD CANDIDATE FOR CERVICAL DEGENERATIVE DISC DISEASE SURGERY?
Patients with radicular pain involving one or more than one nerve roots who have failed conservative treatment are good candidate for surgical management.
The surgical treatment stops the progression of the symptoms and allows optimum environment for the nerve root to heal and recover and resolve the symptoms as well as restore muscle power.
Patients who develop acute deterioration of neurological symptoms or acute onset of symptoms have a good chance of halting the progression as well as allowing recovery of the spinal cord nerve root and neurological function.
Patients who have had neurological deterioration for a long time may not be benefitted with the surgery especially if the symptoms have been stable.
Though a surgery may provide an environment for the spinal cord to heal and recover, but any recovery may not be complete. Patients with pain usually have good relief, those with numbness and tingling may take some time.
WHAT OTHER SURGERIES FOR DEGENERATIVE CERVICAL DISC DISEASE?
The surgeries for cervical degenerative disc disease include anterior cervical discectomy and fusion (ACDF), anterior cervical corpectomy and fusion (ACCF), or hybrid procedure including ACDF and ACCF, posterior microscopic foraminotomy, total cervical disc replacement, posterior laminectomy and fusion, and laminoplasty.
EXERCISES THAT HELP IN CERVICAL DEGENERATIVE DISC DISEASE
Exercises involving strengthening of the core muscles of the neck that is the front and the back muscles of the neck help in stabilization of the cervical spine.
These should usually be performed under the supervision of a physician or a physical therapist especially in patients with cervical degenerative disc disease.
Any injury, sudden movement, loading of the head and neck as well as excessive movement of the neck should be avoided especially in patients with degenerative disc disease of the neck.
Cervical disc degenerative diseases are common phenomena in aging population. Patients are asymptomatic in vast majority of population and do not need any treatment.
Patients who are symptomatic can usually be treated with conservative means with a successful outcome. Patients who have failed conservative measures and patients with sudden or rapid onset or deterioration of neurological symptoms can be treated with surgery with good results.
Patients who have profound neurological involvement may have guarded recovery even after surgical management.