14 March 2019 The cervical spine is made up of 7 vertebrae, which are interspersed with intervertebral discs. These discs are made up of an outer fibrous ring and a gel-like centre —the nucleus pulposus . As the spine bends, twists or extends, they undergo changes in shape. In the cervical region the spinal canal protects the spinal cord, which carries nerve impulses to the arms and legs. What are the main causes of a herniated cervical disc? Compared to the lumbar spine, the burden upon the cervical spine throughout its life is much lower. However, the mobility of the neck is greater and it is just as vulnerable to postural deficiencies , often related to professional activity. Therefore, cervical intervertebral discs are also susceptible to wear and degeneration , losing their flexibility and ability to absorb the burden arising as a result of day-to-day activities. When an intervertebral disc loses its physiological characteristics, the fibrous ring can break, leading to the displacement of fragments of the nucleus pulposus into the spinal canal, forming what is known as a herniated or ‘slipped’ disc . Such situations may arise insidiously or may be triggered by: Sudden movements; Stress overload on the cervical spine. What are the consequences of a herniated cervical disc? The collapse of the degenerated disc also leads to a disc prolapse and a reduction in the size of the intervertebral canals , from which the nerve roots leave; these originate in the spinal cord and go in the direction of the upper limbs. Subsequently, deformation of adjacent vertebral endplates will also take place, with the formation of bone spurs, osteophytes , which can also reduce the diameter of the spinal canal or of the intervertebral canals. What pathologies are associated with herniated cervical disc and how are they diagnosed? Spinal herniation is one of the areas dealt with by neurosurgery and orthopaedics. There are two distinct pathological situations , which have different forms of clinical development and require different treatment: Nucleus pulposus disc herniation - acute; Osteophytic disc herniation — chronic. Several complementary methods may be used in the diagnosis of herniated cervical disc: Simple radiography: this is the imaging method most commonly used to diagnose dislocation or fractures after cervical trauma. In degenerative disease, its capacity for providing information is limited, It may show a decrease in disc space and the formation of osteocytes on the margins of the vertebral bodies; Computer tomography (CT): is the best examination for diagnosing changes in bone structures. It also enables observation of changes in the intervertebral disc, the dimensions of the spinal canal and assessment of the degree of disc projection into the canal; Magnetic Resonance (MRI): is the best examination for assessing the neurological structures, spinal cord and roots of the cauda equina, together with their relationship with the protrusion or extrusion of disc fragments; Myelography: is the examination that is carried out when it is not possible to perform an MRI, and consists of a contrast injection into the dural sac followed by a CT scan. It allows assessment of the dimensions of the spinal canal and any areas of spinal or root compression; Electromyography: This studies the function of peripheral nerves in situations in which there have been motor or sensory changes in the limbs, allowing for a differential diagnosis between peripheral neuropathy and affectation of the nerve root as a result of compression at the spine. This article was written with the support of physicians and other clinical professionals from the Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
