The roots of the cervical nerves C1 through C8 come out of the spine above the vertebra with the same number except C8 which comes out of the cervical spine below the C7 vertebra. The nerves then split to innervate all the muscles of the shoulder, arm, forearm, and hand giving them motor function and sensitivity.
When any of these nerves is subjected to irritation through compression or inflammation, the symptoms of tingling, pain and decreased tenderness and decreased muscle strength in the path and territory of the innervation of this root arise more or less intensely.
The symptomatology of cervical radiculopathy may appear intermittently at first, with ups and downs, but may also appear more or less suddenly. The pain may be felt in one place (shoulder or elbow pain) or along a distally radiated path to the hand and fingers. These symptoms can affect grip strength as well as alter the type of handwriting. During these phases of more severe pain, cervical spine mobility is greatly diminished by the risk of worsening local or irradiated pain.
Some patients experience improvement of the pain in the lying position with the arm raised and the hand behind the head, because it indirectly decreased the tension in the inflamed root.
Causes of Cervical Radiculopathy
Any situation that compresses or causes nerve irritation can cause cervical radiculopathy. The most common causes are:
- Cervical disc herniation. If the inner material of the intervetebral disc contacts the nerve root (by rupturing the fibrous ring of the disc’s periphery), it causes irritation, inflammation, and compression of the nerve in question, with all the symptoms described. In a young adult this is perhaps the main cause of cervical radiculopathy.
- Cervical canal stenosis (tightening). As part of the degenerative process of the cervical spine, changes in the “wear” of the posterior interapophyseal joints may contribute to the reduction of space available for neurological structures within the cervical canal and thereby to tighten the various cervical roots and spinal cord itself. This is why this type of symptomatology is more common in patients over 60 years.
- Degenerative disease of the cervical discs. When a disc in the cervical spine has evolved in the process of degeneration, the disc becomes narrower, and obviously less movable (stiffer) and overloaded on the posterior interapophyseal joints, which often explains reflex pain in the shoulder blades or of the trapezoids at the posterior base of the neck often associated with difficulty bearing the weight of the head. Narrowing of the cervical discs will also condition a narrowing of foramina (holes where the cervical nerves come out of the spine). In these situations, inflammation and irritation of a cervical nerve is common, so this cause of radiculopathy is more common in patients older than 50 years.
Cervical Radiculopathy Diagnosis
If symptoms do not regress with symptomatic therapy at baseline, the physician should order imaging – static and dynamic X-rays + Magnetic Resonance and computed tomography. In some cases to clarify the nerve root involved in the process, an EMG should be ordered.
Cervical Radiculopathy Treatment
Conservative treatment should always be attempted at the outset through medication, moist heat, and cervical collar immobilization in the acute phase. If however symptoms persist after 6-12 weeks then surgical treatment should be considered. However if severe pain persists or if neurological signs such as decreased muscle strength get worse then surgery should be considered with the alternative treatment.
However, the vast majority of cervical radiculopathies resolve without surgery.
Most common types of surgical treatment:
- Anterior cervical discectomy and intersomatic fusion. It is perhaps the most common type of surgery – see additional information on Anterior Cervical Spine Arthrodesis
- Cervical disc arthroplasty. As an alternative to intersomatic fusion / arthrodesis in recent decades the possibility of replacing the torn and herniated disc with an artificial disc has emerged – see additional information – cervical disc arthroplasty.
Cervical surgery to decrease radiated pain or decreased strength in the upper upper limb has a success rate that according to the literature can be around 80 to 90%. However, like any surgery, cervical spine surgery has risks that should be shared with the patient in the conversation prior to surgery and the outcome of the proposed surgery should be estimated.