Spinal cord syndromes: types, causes, and symptoms
Within the human body is the spinal cord, a long cord that is responsible for transporting nerve impulses from the brain to the rest of the body and vice versa . Thanks to it we can perform any movement, stand up or perceive all kinds of sensations both internal and external.
However, when this one is injured or suffers some kind of pathology , spinal cord syndromes or myelopathies appear . The term spinal cord syndromes groups together a variety of conditions of the spine with consequences that affect both motor skills and sensory abilities.
What are spinal syndromes?
Spinal cord syndromes, or diseases of the spinal cord, refer to a diverse set of symptoms and signs that may vary depending on the location of the spinal cord injury .
Although these conditions do not occur very often, they tend to cause serious effects and consequences on the person’s health, leading, in many cases, to some kind of disability .
This is why a hasty diagnosis of these spinal syndromes, as well as an effective therapeutic intervention, is essential to reduce or compensate in the best way the symptoms of these conditions.
We can distinguish several types of spinal syndromes based on the symptoms that each one of them presents. These symptoms are associated with specific etiological processes; that is, with the causes that have led to the damage or injury. These damages can affect the entire spinal cord cylinder or, conversely, damage only a part of the spinal cord in its transverse section.
At the time when the medical professional has to make the diagnosis of one of these spinal syndromes, he or she should take into account the possibility that it is one of the conditions, such as some autoimmune, muscular or psychiatric diseases, that have similar symptomatology. A comprehensive differential diagnosis will be the key to successful treatment of the patient .
Types of spinal syndromes
As mentioned above, there is a wide variety of classical spinal syndromes. The main way to classify them is by considering their symptoms, as well as the time pattern of these symptoms.
1. Complete spinal cord injury
In those cases of complete spinal cord injury, or transverse myelopathy, the person will experience the disappearance of all sensory modalities , as well as a bilateral alteration of the motor pathways below the injury.
This syndrome is characterized by sensory and motor symptoms. The sensory symptoms characteristic of a complete spinal cord injury are
- Paresthesias or abnormal sensations of tingling and changes in body temperature These sensations occur in the section corresponding to the level of the injury.
- Localized pain in the vertebrae .
- Root pain depending on the location of the lesions. If it is a cervical injury, the person will experience pain in the arms. If it is a thoracic or lumbar injury, the pain will be centered in the chest and abdomen or in the legs.
- Low sensory threshold or loss of all sensory modes.
On the other hand, symptoms related to motor functions include
- Lesions in the lower motor neurons that cause muscle atrophy, fasciculations or small muscle contractions that can be seen under the skin and hyporeflexia or decreased reflex response.
- Paraparesis/paraplegia or tetraparesis/tetraplegia . The person experiences paralysis or mobility problems, both to a variable degree, in the lower extremities or all four extremities.
2. Incomplete spinal cord injury
In cases of incomplete spinal cord injury or syndromes, the spinal cord is not completely damaged at the transverse level , so the person does not experience either total paralysis or total loss of sensation.
There are also several types of incomplete spinal cord injuries that differ according to the set of symptoms they cause.
Spinal cord hemisection or Brown-Séquard syndrome
In this case the person suffers an alteration or damage to the hemimedulla . However, it is very difficult for this injury to hit just the midline of the spine or to appear purely unilaterally.
The medullary hemisection may be caused by some kind of infection or by an injury at that particular point. Likewise, certain tumour bodies or degenerative diseases can also cause this type of syndrome.
The symptoms of this condition usually appear at an ipsilateral level and below the level of the lesion, the most important being paralysis of the first homolateral motor neuron and lack of sensitivity to pain and temperature.
Symptoms of the medullary hemisection include:
- Homolateral paralysis.
- Thermoanalgesia or insensitivity to contralateral temperature.
- Muscle weakness and paralysis .
- Loss or diminution of sensitivity and sensory perception
- Alterations in the perception of posture and position (proprioceptive system)
Centromedullary syndrome
In centromedullary type disease, the damage is found in the central grey matter and in the spinal tracts that cross the central area of the cord. In addition, this injury can dissipate centrifugally affecting other anatomical pathways.
Among the sensory symptoms we find a loss of sensitivity to pain and temperature . While on a motor level the person may experience muscle atrophy, twitching, muscle weakness and hyporeflexia.
Combined posterior and lateral cord injury
In this type of injury the person may experience motor symptoms such as muscle weakness, spasticity or constant muscle contraction, hyperreflexia and Babinski’s reflex, which is the dorsal extension of the big toe.
At the sensory level, symptoms include alterations in the proprioceptive system and in sensitivity to vibration .
Isolated posterior cord injury
In this case the damage is only caused to certain cords or back fibres. This injury causes an alteration in the person’s proprioceptive and vibratory sensitivity, as well as ataxia or difficulties in the coordination of movements. In addition, the person may also experience stabbing pain in the legs and urinary incontinence .
Anterior horn syndrome
Compared to all other conditions, in anterior horn syndrome only pure motor symptoms of second motor neuron atrophy appear. These symptoms include twitching, muscle weakness, hypotonia and hyporeflexia in one or more muscle groups. It also causes an absence of reflexes.
Combined pyramid duct and anterior horn syndrome
In this last syndrome of incomplete medullary nature, also only motor symptoms appear ; with the difference that symptoms of the first and second motor neuron develop simultaneously within the same muscle group. The cause is an anomaly present in the pyramidal tracts and in the anterior horns.
3. Spinal Vascular Syndromes
Unlike the syndromes of complete and incomplete spinal cord injuries, in spinal cord vascular syndromes the origin of the abnormality is found in an abnormality of blood flow in any area of the spine .
Spinal cord arterial ischemia syndromes
In this case, the suspension of the arterial blood supply in the marrow has as a direct result the appearance of ictus or transient ischemic accidents.
Spinal cord ischemia syndrome
These types of syndromes are much rarer than the previous ones. In addition, tend to affect the lower extremities , producing bilateral syndromes or complete transverse syndromes almost always in an asymmetric way.
The main causes of this type of pathology are arteriovenous malformations, fibrocartilaginous embolisms and the effects of decompression.
Spinal cord bleeding syndromes
In these syndromes we can differentiate between intramedullary and extramedullary haemorrhage . Intramedullary haemorrhage is produced by a vascular rupture causing spinal pain, paresis and sensory alterations below the level of the lesion.
As for extramedullary hemorrhage, this is much rarer. In this case the person experiences severe spinal pain at the site of the stroke, coupled with symptoms similar to those of a cerebral subarachnoid hemorrhage. These include numbness in one part of the body, seizures, neck tension, vision problems, nausea, or muscle pain.