Definition
Cervical radiculopathy is the disturbance or impairment of cervical nerve function(s) caused by the compression of nerve roots. These roots branch out from the spinal cord through openings of the vertebrae called foramina.
Pathology
Radiculopathy of the cervical spine arises from a number of pathologies of the upper spinal tract commonly leading to the compression, irritation and damage of one or more cervical nerves.
Radiculopathy is likely due to the impingement and inflammation of the cervical nerve roots caused by the pressure of a bulged disc (herniation), the formation of hypertrophic or bone spurs in the facet joints, stenosis of the vertebral foramina or a direct compression onto the spinal cord by a tumor or other expanding masses.
Other pathologies including spinal fractures and sarcoidosis (systemic granulomatous disease affecting the lungs and lymphatic systems) may elicit similar symptoms to cervical radiculopathy.
Generally, radiculopathy to the cervical spine occurs less frequently compared to the radiculopathy of the lumbar spine.
Classification
The classification of cervical radiculopathy relates to the cervical nerves involved, each one producing distinct symptoms according to their respective dermatomes.
The illustrations represent above, the dermatome sensory areas (blue), and below the muscles affected by motor dysfunction of the respective cervical nerves.
C5 radiculopathy: weakness to the deltoid and biceps muscles of the upper arm; reduced biceps reflex.
C6 radiculopathy: weakness in the extension of the brachioradialis muscle (elbow flexion) and wrist (extension) including brachioradialis reflex. Thumb paresthesia (pins and needles sensation).
C7 radiculopathy: weakness of the triceps muscle (elbow extension) and wrist flexion, reduced triceps reflex. Paresthesia in the index, middle and ring fingers.
C8 radiculopathy: weakness in flexion of the distal phalanges of the middle and index fingers. Paresthesia of the little finger.
T1 radiculopathy: affects the motor function of the interossei muscles of the hand. Altered sensation at the ulnar side of the forearm.
Reduced sensibility may occur in the respective dermatomes of C5 to T1.
Causes
In young individuals, disk herniation following an injury is the predominant cause of cervical radiculopathy (up to 25%). The mechanisms leading to disk herniation involve a sudden, forceful movement of the neck (e.g. extension, flexion, lateral bending, rotation) or lifting heavy weights. A bulged disk reduces the foramen space causing nerve root compression and possibly damage.
In the population above 60 years of age, cervical radiculopathy may arise from spinal or foraminal stenosis consequent to degenerative changes of the facet joints diminishing the foraminal space.
Particularly in elderly people, cervical radiculopathy may be the consequence of cervical osteoarthritis, and intravertebral disk degeneration, whereby the disk becomes stiff and compressed, or the presence of growing bone spurs (osteophytes) impinging onto the nerve root.
Tumors of the spine, cervical synovial cysts, synovial chondromatosis of the facet joint, spinal infections and inflammation of the cervical radicular vessels are other possible causes of the disease.
Risk factors
The risk factors leading to cervical radiculopathy are several:
Ageing
Heavy labour
Weightlifting
Sports involving frequent neck bending, flexion, extension, (swimming, tennis, gymnastics)
Driving
Operating / vibrating machinery
Spine tumors
Cervicalsynovial cyst
Synovial chondromatosis in the facet joint
Inflammation of the cervical arteries
Spinal infections
Smoking
Symptoms
The symptoms of cervical radiculopathy vary depending on the cervical levels and the nerves affected following the dermatome map. The symptoms are proportional to the severity of the disease and include.
Headache
Pain to neck, upper/lower arm, interscapular region (between the shoulder blades), hand and fingers
Pain manifesting with neck movement
Muscular weakness of one arm and hand. Restricted overhead (C7) or grip (C7) function
Tingling sensation to one thumb (C6) or middle finger (C7)
Pins and needles sensation
Numbness
Diagnosis
Medical examination begins with the patient’s history including previous injuries, diseases and physical activities relative to profession and sport.
The examiner determines the increase or relief of symptoms when the patient actively moves the neck. It is helpful to run the Spurling test, shoulder abduction test (lift the arm over head relieves symptoms), and vertical head traction test.
Medical evaluation also includes the neurological assessment of sensory and motor functions as well as reflexes.
X-rays and CT scans are taken to determine the alignment of the vertebrae, the presence of disc herniation, the dimension of the spinal canal and the growth of bone spurs.
MRI of the neck is useful to detect nerve compression, bulging /herniation of the disk, the diameter of the spinal canal and the integrity of the spinal cord.
Electromyography and nerve conduction studies help distinguish cervical radiculopathy from other diseases affecting the nerves (diabetes).
Nerve root block can be used as a diagnostic tool. It consists in the local injection of anaesthetics, which improves pain if the specific nerve is affected.
The examiner may also consider differential diagnosis for a patient’s symptoms like: brachial plexus injury, cervical disc injury, cervical facet joint syndrome, cervical spine injuries, rotator cuff injury of the shoulder, and carpal tunnel syndrome.
Treatment
Nonoperative treatment
Conservative treatment is usually the first strategy to address cervical radiculopathy. It consists of wearing a collar for a short period of time to limit neck movement and allow the neck muscles to rest.
Physical therapy aims at stretching and strengthening the neck muscles to support the cervical spine.
NSAIDs (aspirin and ibuprofen) are given orally to reduce pain and inflammation.
With persisting symptoms, corticosteroids are administered via translaminar and/or transforaminal epidural injection to reduce inflammation and swelling.
Analgesics may also help pain management.
Antidepressants, antiepileptics and opioids can be useful to combat chronic neuropathic pain.
Acupuncture may be effective in some patients.
Surgical treatment
With persisting symptoms and compromise of the spinal cord and or nerve roots, surgery may be required to decompress the nerve roots, restore spine stability and vertebrae alignment. The surgical approach differs depending on the pathology underlying cervical radiculopathy.
Anterior cervical discectomy and fusion (ACDF) via access from the front of the neck includes the removal of the degenerated disk and rhizolysis (decompression of the nerve root). The fusion of the adjacent two vertebrae is achieved with disk replacement using a bone graft, with or without the implantation of a cage. In addition, a plate and screws can be used to enhance stabilisation.
Artificial disk replacement (ADR; see also the pathology: Disk herniation. LINK) is performed through an anterior approach to the neck, in which the diseased disk is replaced with a metal prosthesis, which allows regaining of some mobility.
However, some studies have shown that at two years post-surgery artificial disc replacement failed to bring a better outcome compared to anterior cervical decompression and fusion.
Another surgical approach is the posterior lamino-foraminotomy through a posterior access to the neck to remove the bony parts compressing the nerve roots.
Rehabilitation
Often after surgery a collar is worn for 4-6 weeks. After this period a gentle physiotherapy regime is introduced to gradually return to a full range of motion and neck strength.
The recovery after surgery varies depending on the initial pathology and the surgical approach used and may take up to 6 to 12 months.
Complications
Incomplete neurological recovery
Lost range of movement of the cervical spine
Formation of osteophytes
Progress of degenerative changes
Ongoing pain issues.
Prevention
Changes in life style and implementing correct techniques during physical activity are useful to prevent the conditions leading to cervical radiculopathy (e.g. disk herniation).
It is advised to maintain muscular strength to the neck, shoulders, scapulae and the whole spine to alleviate pressure to the vertebrae, disks and ligaments.
Sitting, weight lifting, bending and twisting are to be performed with a correct posture (e.g. by keeping the spine straight and knees bent).
It is also recommended to avoid heavy weights, carry heavy bags, loose excessive weight and quit smoking to improve spinal health and prevent recurrent problems.