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Symptoms usually occur very quickly and are often experienced within one hour of the initial damage. MRI can detect the magnitude and location of the damage 10–15 hours after the initiation of symptoms. Diffusion-weighted imaging may be used as it is able to identify the damage within a few minutes of symptomatic onset.
Clinical features include paraparesis or quadriparesis (depending on the level of the injury) and impaired pain and temperature sensation. Complete motor paralysis below the level of the lesion due to interruption of the corticospinal tract, and loss of pain and temperature sensation at and below the level of the lesion. Proprioception and vibratory sensation is preserved, as it is in the dorsal side of the spinal cord.
Signs (observed by a clinician) and symptoms (experienced by a patient) vary depending on where the spine is injured and the extent of the injury.
A section of skin innervated through a specific part of the spine is called a dermatome, and injury to that part of the spine can cause pain, numbness, or a loss of sensation in the related areas. Paraesthesia, a tingling or burning sensation in affected areas of the skin, is another symptom. A person with a lowered level of consciousness may show a response to a painful stimulus above a certain point but not below it.
A group of muscles innervated through a specific part of the spine is called a myotome, and injury to that part of the spinal cord can cause problems with movements that involve those muscles. The muscles may contract uncontrollably (spasticity), become weak, or be completely paralysed. Spinal shock, loss of neural activity including reflexes below the level of injury, occurs shortly after the injury and usually goes away within a day.
The specific parts of the body affected by loss of function are determined by the level of injury.
Spinal cord injuries at the cervical (neck) level result in full or partial tetraplegia (also called quadriplegia). Depending on the specific location and severity of trauma, limited function may be retained.
Additional signs and symptoms of cervical injuries include low heart rate, low blood pressure, problems regulating body temperature, and breathing dysfunction. If the injury is high enough in the neck to impair the muscles involved in breathing, the person may not be able to breathe without the help of an endotracheal tube and mechanical ventilator.
Neurogenic shock is a distributive type of shock resulting in low blood pressure, occasionally with a slowed heart rate, that is attributed to the disruption of the autonomic pathways within the spinal cord. It can occur after damage to the central nervous system such as spinal cord injury. Low blood pressure occurs due to decreased systemic vascular resistance resulting in pooling of blood within the extremities lacking sympathetic tone. The slowed heart rate results from unopposed vagal activity and has been found to be exacerbated by hypoxia and endobronchial suction.
Neurogenic shock can be a potentially devastating complication, leading to organ dysfunction and death if not promptly recognized and treated. It is not to be confused with spinal shock, which is not circulatory in nature.
Spinal shock was first defined by Whytt in 1750 as a loss of accompanied by motor paralysis with initial loss but gradual recovery of reflexes, following a spinal cord injury (SCI) – most often a complete transection. Reflexes in the spinal cord below the level of injury are depressed (hyporeflexia) or absent (areflexia), while those above the level of the injury remain unaffected. The 'shock' in spinal shock does not refer to circulatory collapse, and should not be confused with neurogenic shock, which is life-threatening
Anterior spinal artery syndrome (also known as "anterior spinal cord syndrome", or "Beck's syndrome") is a medical condition where the anterior spinal artery, the primary blood supply to the anterior portion of the spinal cord, is interrupted, causing ischemia or infarction of the spinal cord in the anterior two-thirds of the spinal cord and medulla oblongata. It is characterized by loss of motor function below the level of injury, loss of sensations carried by the anterior columns of the spinal cord (pain and temperature), and preservation of sensations carried by the posterior columns (fine touch, vibration and proprioception). Anterior spinal artery syndrome is the most common form of spinal cord infarction.
The onset of myelomalacia may be so subtle that it is overlooked. Depending on the extent of the spinal cord injury, the symptoms may vary. In some cases, the symptom may be as common as hypertension. Though every case is different, several cases reported loss of motor functions in the extremities, areflexia or sudden jerks of the limbs, loss of pain perception, or even paralysis; all of which are possible indicators of a damaged and softened spinal cord. In the most severe cases, paralysis of the respiratory system manifests in death.
Neurogenic shock can result from severe central nervous system damage (brain injury, cervical or high thoracic spinal cord). In more simple terms: the trauma causes a sudden loss of background sympathetic stimulation to the blood vessels. This causes them to relax (vasodilation) resulting in a sudden decrease in blood pressure (secondary to a decrease in peripheral vascular resistance).
Neurogenic shock results from damage to the spinal cord above the level of the 6th thoracic vertebra. It is found in about half of people who suffer spinal cord injury within the first 24 hours, and usually doesn't go away for one to three weeks.
In spinal cord injuries above T6, neurogenic shock may occur, from the loss of autonomic innervation from the brain. Parasympathetic is preserved but the synergy between sympathetic and parasympathetic system is lost in cervical and high thoracic SCI lesions. Sacral parasympathetic loss may be encountered in lesions below T6 or T7. Cervical lesions cause total loss of sympathetic innervation and lead to vasovagal hypotension and bradyarrhythmias – which resolve in 3–6 weeks. Autonomic dysreflexia is permanent, and occurs from Phase 4 onwards. It is characterized by unchecked sympathetic stimulation below the SCI (from a loss of cranial regulation), leading to often extreme hypertension, loss of bladder or bowel control, sweating, headaches, and other sympathetic effects.
Posterior spinal artery syndrome is much rarer than its anterior counterpart as the white matter structures that are present are much less vulnerable to ischemia since they have a better blood supply. When posterior spinal artery syndrome does occur, dorsal columns are damaged and ischemia may spread into the posterior horns. Clinically the syndrome presents as a loss of tendon reflexes and loss of joint position sense
Clinical signs and symptoms depend on which spinal cord level (cervical, thoracic or lumbar) is affected and the extent (anterior, posterior or lateral) of the pathology, and may include:
- upper motor neuron signs—weakness, spasticity, clumsiness, altered tonus, hyperreflexia and pathological reflexes, including Hoffmann's sign and inverted Plantar reflex (positive Babinski sign);
- lower motor neuron signs—weakness, clumsiness in the muscle group innervated at the level of spinal cord compromise, muscle atrophy, hyporeflexia, muscle hypotonicity or flaccidity, fasciculations;
- sensory deficits;
- bowel/bladder symptoms and sexual dysfunction.
Anterior spinal artery syndrome is necrosis of tissue in the anterior spinal artery or its branches. It is characterised by pain which radiates at onset and sudden quadraplegia (paralysis of all four limbs) or paraplegia (paralysis of the lower body). Within days, flaccid limbs become spastic and hyporeflexia (underactive nerve responses) turns into hyperreflexia (overactive nerve responses) and extensor plantar nerve responses. Sensory loss to pain and temperature also occurs up to the level of damage on the spinal cord, as damage to different areas will affect different parts of the body.
In diagnosis, other causes of abrupt paralysis should be excluded such as cord compression, transverse myelitis (inflammation of the spinal cord) and Guillain–Barré syndrome. A specific cause of the infarction should be looked for, such as diabetes, polyarteritis nodosa (inflammatory damage of vessels) or systemic lupus erythematosus. Neurosyphilis is also a known cause. Other causes include:
Treatment is supportive and aims to relieve symptoms. The prognosis is dependent upon individual circumstances and factors.
When myelomalacia occurs, the damage done to the spinal cord may range from minimal to extensive. The spinal cord and the brain work together, making them the key components of the central nervous system. Damage to this system affects specific functions of the body, primarily relating to the function of muscles. The areas most commonly injured include the cervical vertebrae (C1-C7), and the lumbar spine (L1-L5).
SCIWORA may present as a complete spinal cord injury (total loss of sensation and function below the lesion) or incomplete spinal cord injury (some sensation and/or function is preserved). It is present in a significant number of children with SCI. Notably, the clinical symptoms can present with a delay of hours to days after the trauma. This phenomenon was primarily seen in children but was reported in adults as well. The duration of symptoms varies widely. A full recovery can be achieved without treatment within minutes to hours and permanent injuries might prevail. Overall, there seems to be a relation between extent of damage to the spinal cord and the clinical prognosis. The prognostic value of intra- and extra-medullary MRI findings is subject of ongoing research in the field of SCIWORA.
Spinal cord injury without radiographic abnormality (SCIWORA) is a spinal cord injury (SCI) with no evidence of injury to the spinal column present on radiographs. Spinal column injury is trauma that causes fracture of the bone or instability of the ligaments in the spine; this can coexist with or result in injury to the spinal cord itself but each injury can occur without the other. Abnormalities might show up on magnetic resonance imaging (MRI), but the term was coined before MRI was in common use.
Myelopathy describes any neurologic deficit related to the spinal cord. When due to trauma, it is known as (acute) spinal cord injury. When inflammatory, it is known as myelitis. Disease that is vascular in nature is known as vascular myelopathy. The most common form of myelopathy in human, "cervical spondylotic myelopathy (CSM)", is caused by arthritic changes (spondylosis) of the cervical spine, which result in narrowing of the spinal canal (spinal stenosis) ultimately causing compression of the spinal cord. In Asian populations, spinal cord compression often occurs due to a different, inflammatory process affecting the posterior longitudinal ligament.
Brown-Séquard syndrome may be caused by a spinal cord tumour, trauma [such as a gunshot wound or puncture wound to the cervical (neck) or thoracic spine (back)], ischemia (obstruction of a blood vessel), or infectious or inflammatory diseases such as tuberculosis, or multiple sclerosis. In its pure form, it is rarely seen. The most common cause is penetrating trauma such as a gunshot wound or stab wound to the spinal cord. Decompression sickness may also be a cause of Brown-Séquard syndrome.
The presentation can be progressive and incomplete. It can advance from a typical Brown-Séquard syndrome to complete paralysis. It is not always permanent and progression or resolution depends on the severity of the original spinal cord injury and the underlying pathology that caused it in the first place.
Magnetic resonance imaging (MRI) is the imaging of choice in spinal cord lesions.
Brown-Séquard syndrome is an incomplete spinal cord lesion characterized by findings on clinical examination which reflect hemisection of the spinal cord (cutting the spinal cord in half on one or the other side). It is diagnosed by finding motor (muscle) paralysis on the same (ipsilateral) side as the lesion and deficits in pain and temperature sensation on the opposite (contralateral) side. This is called ipsilateral hemiplegia and contralateral pain and temperature sensation deficits. The loss of sensation on the opposite side of the lesion is because the nerve fibers of the spinothalamic tract (which carry information about pain and temperature) crossover once they meet the spinal cord from the peripheries.
Symptoms vary depending on whether the spinal cord, brain stem, nerves or their blood supply is affected by the pressure.
Symptoms become apparent when the neck is bent. They include:
- Posterior head pain
- Neck weakness
- Periods of confusion
- Dysarthria (difficulty swallowing or talking due to loss of muscle control)
- Dizziness
- Loss of sensation
- Cranial nerve disturbance
- Loss of the ability to know how joints are positioned
- Lhermitte's sign ('electric shock sensation' down spine and/or to the extremities when the neck is flexed forward)
- Weakness of the arms and legs
- Orthostatic hypotension
- Patients will go into a pool and notice that below their belly button the water is not as cold as it is above.
Complications from this can include hydrocephalus, pseudotumor cerebri or syringomyelia because it blocks the flow of fluid around the brain and spinal cord.
In children, symptoms may include:
- Lesions, hairy patches, dimples, or fatty tumours on the lower back
- Foot and spinal deformities
- Weakness in the legs (loss of muscle strength and tone)
- Change in or abnormal gait including awkwardness while running or wearing the tips or side of one shoe
- Low back pain
- Scoliosis (abnormal curvature of the spine to the left or right)
- Urinary irregularities (incontinence or retention)
Tethered spinal cord syndrome may go undiagnosed until adulthood, when sensory, motor, bowel, and bladder control issues emerge. This delayed presentation of symptoms relates to the degree of strain on the spinal cord over time.
Tethering may also develop after spinal cord injury. Scar tissue can block the flow of fluids around the spinal cord. Fluid pressure may cause cysts to form in the spinal cord, a condition called syringomyelia. This can lead to additional loss of movement or feeling, or the onset of pain or autonomic nervous system symptoms.
In adults, onset of symptoms typically include:
- Severe pain (in the lower back and radiating into the legs, groin, and perineum)
- Bilateral muscle weakness and numbness
- Loss of feeling and movement in lower extremities
- Urinary irregularities (incontinence or retention)
- Bowel control issues
Neurological symptoms can include a mixed picture of upper and lower motor neuron findings, such as amyotrophy, hyperreflexia, and pathologic plantar response, occurring in the same limb. Profound sensory changes, such as loss of pain, temperature, and proprioceptive sensations, are common. Last, progressive symptoms of a neuropathic bladder are noted on over 70% of adult patients, versus only 20% to 30% of children. These symptoms include urinary frequency and urgency, feeling of incomplete voiding, poor voluntary control, and urge and stress incontinence. Chronic recurrent infections are common and occasionally lead to nephrolithiasis (kidney stones), renal failure, or renal transplantation. Female patients also give a history of ineffective labor and postpartum rectal prolapse, presumably due to an atonic pelvic floor.
Understanding the meaning of signs and symptoms for the clinical syndrome of lumbar stenosis requires an understanding of what the syndrome is, and the prevalence of the condition. A recent review on lumbar stenosis in the Journal of the American Medical Association's "Rational Clinical Examination Series" emphasized that the syndrome can be considered when lower extremity pain occurs in combination with back pain. This syndrome occurs in 12% of older community dwelling men and up to 21% of those in retirement communities.
The leg symptoms in lumbar spinal stenosis (LSS) are similar to those found with vascular claudication, giving rise to the term pseudoclaudication. These symptoms include pain, weakness, and tingling of the legs, which may radiate down the leg to the feet. Additional symptoms in the legs may be fatigue, heaviness, weakness, a sensation of tingling, pricking, or numbness and leg cramps, as well as bladder symptoms. Symptoms are most commonly bilateral and symmetrical, but they may be unilateral; leg pain is usually more troubling than back pain.
Pseudoclaudication, now referred to as neurogenic claudication, typically worsen with standing or walking and improve with sitting. The occurrence is often related to posture and lumbar extension. Lying on the side is often more comfortable than lying flat, since it permits greater lumbar flexion. Vascular claudication can resemble spinal stenosis, and some individuals experience unilateral or bilateral symptoms radiating down the legs rather than true claudication.
The first symptoms of stenosis include bouts of low back pain. After a few months or years, this may progress to claudication. The pain may be radicular, following the classic neurologic pathways. This occurs as the spinal nerves or spinal cord become increasingly trapped in a smaller space within the canal. It can be difficult to determine whether pain in the elderly is caused by lack of blood supply or stenosis; testing can usually differentiate between them but patients can have both vascular disease in the legs and spinal stenosis.
Among people with lower extremity pain in combination with back pain, lumbar stenosis as the cause is two times more likely in those older than 70 years of age while those younger than 60 years it is 0.40 as likely. The character of the pain is also useful. When the discomfort does not occur while seated, the likelihood of LSS increases considerably around 7.4 times. Other features increasing the likelihood of lumbar stenosis are improvement in symptoms on bending forward 6.4 times, pain that occurs in both buttocks or legs 6.3 times, and the presence of neurogenic claudication 3.7 times. Alternately, the absence of neurogenic claudication makes lumbar stenosis much less likely as the explanation for the pain.
A variety of nerve types can be subjected to neurapraxia and therefore symptoms of the injury range in degree and intensity. Common symptoms of neurapraxia are disturbances in sensation, weakness of muscle, vasomotor and sudomotor paralysis in the region of the affected nerve or nerves, and abnormal sensitivity of the nerve at the point of injury. It has been observed that subjective sensory symptoms include numbness, tingling, and burning sensations at the site of the injury. Objective sensory symptoms are generally minimal in regards to touch, pain, heat, and cold. In cases of motor neuron neurapraxia, symptoms consist of flaccid paralysis of the muscles innervated by the injured nerve or nerves.
Symptoms are often transient and only last for a short period of time immediately following the injury. However, in severe cases of neurapraxia, symptoms can persist for weeks or months at a time.
Basilar invagination is invagination (infolding) of the base of the skull that occurs when the top of the C2 vertebra migrates upward. It can cause narrowing of the foramen magnum (the opening in the skull where the spinal cord passes through to the brain). It also may press on the lower brainstem.
This is similar to Chiari malformation. That, however, is usually present at birth.
Lumbar spinal stenosis (LSS) is a medical condition in which the spinal canal narrows and compresses the nerves at the level of the lumbar vertebrae. This is usually due to the common occurrence of spinal degeneration that occurs with aging. It can also sometimes be caused by spinal disc herniation, osteoporosis, a tumor, or trauma. In the cervical (neck) and lumbar (low back) region it can be a congenital condition to varying degrees.
It is also a common symptom for those who suffer from various skeletal dysplasias such as with pseudoachondroplasia and achondroplasia at an early age.
Spinal stenosis may affect the cervical or thoracic region in which case it is known as cervical spinal stenosis or thoracic spinal stenosis. In some cases, it may be present in all three places in the same patient. Lumbar spinal stenosis can cause low back pain, abnormal sensations, and the absence of sensation (numbness) in the legs, thighs, feet or buttocks, or loss of bladder and bowel control.
Tethered spinal cord syndrome is a clinical entity which is manifested by progressive motor and sensory changes in:
- legs
- incontinence
- back of leg pain
- scoliosis
In order to understand the pathophysiology that is involved in a tethered spinal cord, the reduction/oxidation ratio as to be used in vivo of cytochrome alpha and alpha 3 to signal the oxidative metabolic functioning in humans. Studies have found that marked metabolic and electrophysiological susceptibility to hypoxic stress to the lumbar and sacral portion of the spinal cord under traction with various weights. Similar effects were found in redox behavior of tethered spinal cord during the surgical procedures to repair it. This can be due to impairment of mitochondrial oxidative metabolism under constant or intermittent stretching. The act of prolonged stretching can lead to structural damage to the neural perikarya and eventually the axons in neurons. The untethering process can improve the oxidative metabolism and can help to repair injured neurons.