Cervical Radiculopathy or Herniated Nucleus Pulposus (HNP): Symptoms, Treatment- Surgery
Cervical vertebrae consists of seven vertebral columns, all of which together form the upper part of spine. When one of the nerve roots near the cervical vertebrae is compressed, it results in the damage or disturbance of nerve function. This is known as cervical radiculopathy. In this condition the sensory nerves are affected by a protruding intervertebral disk.
Cervical radiculopathy involves numbness, pain, and muscular spasm of the neck, radiating to the shoulders, caused by compression and irritation of the cervical nerve roots by a protruding intervertebral disk.
When a nerve root in the cervical spine is irritated through inflammation or compression, the symptoms can radiate along that nerve's pathway into the arm and hand. The specific symptoms will primarily depend on which nerve is affected. This pain may also be referred to as radicular pain.
Cervical Radiculopathy is also known as:
- Cervical disk syndrome.
- Herniated inter vertebral disk.
- Herniated nucleus pulposus (HNP).
- Prolapsed inter vertebral disk (PIVD).
- Ruptured disk.
- Slipped disk.
Classification and Types of Cervical Radiculopathy or Herniated Nucleus Pulposus (HNP)
The symptoms of cervical radiculopathy differ depending on the nerve which is affected. For instance, if the nerve root that runs above the C6 vertebra is affected, it is termed as "C6 radiculopathy".
Though the patient's specific symptoms can widely vary, following are the common types and symptoms of cervical radiculopathy:
- C5 Radiculopathy- This causes weakness and/or pain in the upper arms and shoulders, specifically may cause discomfort around the shoulder blades which rarely causes tingling or numbness.
- C6 Radiculopathy- This causes weakness and/or pain along the length of the arm, including the biceps i.e. the muscles in front of the upper arms, index finger, wrists, and the thumb. This is more commonly seen.
- C7 Radiculopathy- This causes weakness and/or pain from the neck to the hand and can include the triceps i.e. the muscles on the back of the upper arms and the middle finger. Again more common problem
- C8 Radiculopathy- This causes pain from the neck to the hand, weakness in hand grip, and numbness and pain that can radiate along the inner side of the arm, ring, and little fingers.
Epidemiology of Cervical Radiculopathy or Herniated Nucleus Pulposus (HNP)
Cervical radiculopathy is much less frequent than the lumbosacral radiculopathy. The annual incidence is about 85 cases in a population of 100,000.
About 20-25% of the cases of cervical radiculopathy are caused due to cervical disc herniation. In older patients, cervical radiculopathy is more commonly a result of decreased disc height, foraminal narrowing from osteophyte formation, degenerative changes of the uncovertebral joints anteriorly and of the facet joints posteriorly.
Pathophysiology of Cervical Radiculopathy or Herniated Nucleus Pulposus (HNP)
Vertebral column commonly known as spine or backbone has 33 vertebrae. Of these 33 vertebrae of the spine, 24 are articulate vertebrae, which include seven cervical vertebrae. Spinal nerves are present in bundles in the neck and lumbar section of spinal cord. These bunches of nerves are called plexus. There are three nerve plexus distributed in neck (cervical plexus). Nerves from these cervical plexus disperse into neck, shoulder and upper extremities. The extent of symptoms depends on the level of lesions. Lesion of C5 nerve at foramina of spinal canal in neck may extend over deltoid muscle, as well as outer and lateral side of upper arm. Injury or irritation of C6 nerve will result in weakness in the biceps muscles and wrist extensor muscles and tingling/numbness on lateral side of hand and thumb.
Radicular pain is a symptom secondary to pinched nerve or irritation of the nerve at nerve root close to spinal cord or at foramina before its exit from the spinal canal. Radicular pain spreads along the nerve distribution or dermatome. Radiculopathy or radicular pain may or may not be associated with tingling, numbness or weakness. Pain, tingling and numbness are symptoms of sensory nerve injury. Weakness is an abnormality of the motor division of spinal nerves and observed in muscle groups receiving nerves from injured spinal nerve. Dermatomal distribution of pain of injured 5th cervical nerve in neck is spread over the back of the neck and upper extremities. Radicular nerve root syndromes are secondary to pinched nerve or irritation of the nerve. Nerve could be pinched secondary to pressure from outside caused by disc bulge, disc herniation, foraminal stenosis or degenerative disc disease.
- Herniated Intervertebral Disc (Slipped Disc)- Cervical nerve root compression due to disc herniation.
- Spondylolisthesis- Vertebra slips forward on the lower vertebrae.
- Spinal Stenosis- Narrowing of the spinal canal. Spinal stenosis can be caused by congenital stenosis and spondylolisthesis. Lateral recess stenosis and foraminal stenosis can cause cord compression.
- Infection, growth within the spine or injury- Rare causes.
Causes and Risk Factors of Cervical Radiculopathy or Herniated Nucleus Pulposus (HNP)
As age progresses, disks will lose height and begin bulging. They lose water content and start getting stiff. The vertebrae start moving close together as the disks lose height. The body visualizes this collapsed disk as a possible weak area and starts forming more bone called bone spurs around the disk to strengthen it. These bone spurs in turn contribute to the stiffening of the spine. Bone spurs may narrow down the area of the foramen and pinch the nerve root. These changes that occur with age are commonly called spondylosis or arthritis, and they can occur in everyone with advancing age.
- Cervical radiculopathy can be caused by anything that puts pressure on the nerve roots in the spine.
- In Young People, cervical radiculopathy can be caused due to pressure from herniated disk. It can also be caused due to a pressure from the material from ruptured disk.
- In Older People, cervical radiculopathy can be caused due to degenerative changes in bones or discs, which put pressure on the nerves. Diseases like arthritis may also cause the nerves to compress.
- Factors associated with increased risk may include smoking, heavy manual labor requiring lifting of more than 25 pounds, and driving or operating vibrating equipment. Less frequent causes include an expanding cervical synovial cyst, giant cell arteritis of the cervical radicular vessels, tumors of the spine, synovial chondromatosis in the cervical facet joint and spinal infections.
Signs and Symptoms of Cervical Radiculopathy or Herniated Nucleus Pulposus (HNP)
- Numbness and pain in the shoulder, arm or hand.
- Weakness in the shoulder, arm, or hand.
- Neck pain or headache in the back side of the head and tingling of hands and fingers.
The primary symptom of cervical radiculopathy is pain that spreads into the neck, chest, arm, and/or shoulders. A person with radiculopathy may experience muscle weakness and/or numbness and tingling in fingers or hands. Lack of coordination can also occur, especially in the hands.
Cervical radiculopathy pain travels down the arm in the area of the involved nerve. Cervical radiculopathy usually results in sharp pain. "Pins and needles" sensation or even complete numbness can also occur. There may also be a feeling of weakness with certain activities. Symptoms can worsen with certain movements like extending or straining the neck or turning the head. These symptoms often get better by stretching the shoulder or placing the hand on the head.
Treatment for Cervical Radiculopathy or Herniated Nucleus Pulposus (HNP)
Treatment ranges from medical management to surgery depending upon the condition, symptoms and medical history of a person.
Medical Management includes medications to relieve pain and muscles spasm, epidural injections. Medications can include a combination of cortico steroids or anti inflammatory drugs and painkillers. Medications can be taken either orally or can be injected in the form of epidural injections though epidural injections are more effective as they are injected directly into the affected areas.
Physical Therapy (PT) may include heat, ultrasound, massage, electrical stimulation, stretching, gentle cervical traction and mobilization.
Surgery may be necessary if the pain is unrelenting with severe impairment of function. Procedure performed depends on the overall status of the spine, and the age and health of the patient. Procedures include discectomy (removal of the herniated disc) with laminotomy (a small hole in the bone of the cervical spine surrounding the spinal cord), laminectomy (removal of the bony wall), by needle technique (percutaneous discectomy), and chemonucleolysis (disc-dissolving procedures).
Commonly Used Procedures for Cervical Radiculopathy or Herniated Nucleus Pulposus (HNP) are:
- Anterior Cervical Discectomy: This procedure involves removal of the herniated disc that is causing the pressure. It is often used in conjunction with another procedure known as anterior cervical fusion.
- Anterior Cervical Fusion: This procedure involves fusion of two vertebrae present on either side of the removed disc.
- Apart from this, there may be other surgical procedures for radiculopathy. The procedure will depend on many factors and most importantly the type of problem.
Diagnosis for Cervical Radiculopathy or Herniated Nucleus Pulposus (HNP)
- Symptom Study- Various physical examinations are performed to reproduce symptoms.
- Electromyogram (EMG) and Nerve Conduction Velocity (NCV).
- Computer Assisted Tomography Scan (CT scan).
- Magnetic Resonance Imaging Scan (MRI).