Paralysis: Symptoms, Spinal Cord Injury, Spastic Paralysis, and Causes of Neurological Deficits

Various functions and nerves are affected by the interruption of the spinal cord:

• Motor: Control the movements performed by the muscles
• Autonomic: Responsible for organ functions such as heart rate, blood vessel dilation, and other activities performed by organs
• Sensory: Control sensory perceptions such as temperature and pressure

Depending on the cause, medical professionals distinguish between two forms of paraplegia:

• the traumatic form: results from an injury
• the non-traumatic form: occurs as a result of certain diseases.

The nature of the functional deficits depends on

• which segment of the spinal cord is damaged,
• which nerves are affected, and
• whether the functions are completely or only partially impaired.

Complete spinal cord injury is referred to as plegia, while incomplete injury is referred to as paresis. In complete spinal cord injury, all nerve pathways are severed. Doctors refer to the complete inability to move both legs as paraplegia.

Since spinal cord injury is a lifelong condition, people with this condition are considered severely disabled. They are generally dependent on a wheelchair and receive a lifetime disability benefit based on the severity of their physical disability.

The main cause of spinal cord transection is accidents, such as 

• car accidents,
• bicycle and motorcycle accidents, or
• falls during downhill skiing.

Severe skiing accidents can, among other things, result in paraplegia © faalt | AdobeStock

In addition, paralysis can also result from certain diseases. These include, for example,

• infectious diseases
• degenerative neurological disorders of the brain
• inflammatory neurological disorders (polio, multiple sclerosis)
• Tumors
• Bleeding in the spinal canal
• Interrupted blood supply to the spinal cord due to a narrowed blood vessel (spinal infarction)
• Compression of the spinal cord due to a herniated disc or displaced vertebrae
• Damage caused by radiation therapy as part of cancer treatment

Researchers estimate that only one-third of the nerve cells are affected by the acute injury. Inflammatory processes and the formation of scar tissue then destroy the remaining nerves.

70% of all cases of paraplegia result from injuries sustained in accidents. 

The most common cause of the condition, accounting for about 43 percent of cases, is multiple sclerosis, a relapsing-remitting disease of the central nervous system.

The interruption of the spinal cord immediately causes spinal shock in those affected. This paralyzes all functions below the damaged vertebral segment. The affected limbs are flaccid and immobile. The patient can no longer feel them.

The autonomic nervous system is also involved in the disease process. This can lead to dilation of the blood vessels, which in the worst case can result in acute circulatory failure. If the area above the fifth thoracic vertebra is injured, the heartbeat and breathing cease.

Patients who suffer spinal shock require immediate treatment in a hospital intensive care unit. A few weeks or months later, the acute state of shock then progresses to paraplegia.

With timely emergency treatment, at least partial recovery of the affected autonomic nerves occurs some time after the spinal cord is severed.

Complete paraplegia is characterized by a total loss

• of motor functions (muscle paralysis) and
• all sensory perceptions.

The patient feels no pain or pressure in the affected areas of the body. Furthermore, they no longer feel their legs, for example; it feels as though they are not there at all. They have also lost their sense of temperature.

Long-term consequences of the accident or the underlying condition include sexual impotence in both men and women, despite a normal sex drive.

In cases of complete and partial paraplegia, the first symptoms are an inability to empty the bladder and fecal retention. As the condition progresses, this leads to urinary incontinence and/or fecal incontinence (involuntary leakage of urine and/or stool). However, some patients suffer from lifelong constipation.

If nerve impulse transmission is interrupted in the cervical spine region (cervical vertebrae C1 through C7), the condition is referred to as tetraplegia or tetraparesis. These patients with partial spinal cord injury have limited movement in both arms and legs. If the cervical vertebrae C1 through C4 are affected, the patient also suffers from diaphragmatic paralysis and requires immediate mechanical ventilation.

Spinal cord injuries can result from vertebral fractures © TeraVector | AdobeStock

If signal transmission below the cervical spine is impaired, paralysis of the legs occurs (paraplegia, paraparesis). Damage to the spinal cord in the thoracic region also results in the loss of function in certain trunk muscles.

Spinal cord injuries in the lumbar region result in partial loss of leg mobility. If the spinal cord is injured at the level of the lowest vertebrae (sacral cord, vertebrae S1 through S5), this results in paralysis of the foot muscles, bladder and bowel problems, and sexual dysfunction.

The flaccid paralysis that occurs shortly after spinal shock transforms into spastic paralysis in the following weeks. This is because the muscles spasm as the newly formed nerve connections in the spinal cord are not functional.

In most cases, a provisional diagnosis of paraplegia is made based on the patient’s description of the accident. An X-ray examination of the spine and other imaging techniques allow for a good assessment of the exact extent of the damage.

Neurological tests provide information about any remaining sensation and mobility in the limbs. Ultrasound images show whether and to what extent internal organs such as the bladder and kidneys are affected by the spinal cord injury. Blood pressure and heart rate measurements also provide insights into the patient’s condition.

Paraplegia caused by an underlying medical condition requires a separate evaluation. In addition, the underlying condition that caused the paraplegia must be treated.

Treatment of paraplegia caused by an underlying medical condition is

• causally (targeted at the underlying causes) and
• symptomatic (treating accompanying symptoms).

For example, constipation is treated with laxatives. Bladder catheters ensure unimpeded emptying of the bladder.

Using imaging techniques, the treating specialist determines whether surgery would be beneficial for the patient. Acute cases involving spinal shock are treated immediately in the intensive care unit. There, 

• heart function,
• breathing, and
• other vital signs of the emergency patient

are monitored and stabilized.

A high dose of cortisone is administered to prevent any inflammation of the damaged nerves. The patient also receives pain medication.

For accident victims with an unstable spinal fracture, the spine can only be stabilized through surgery. In cases of spinal cord contusion, surgical intervention can also prevent further damage.

People with spinal cord injuries can often manage their daily lives well © Drazen | AdobeStock

A complete severing of the spinal cord is, in principle, irreversible. The severed spinal cord will not regrow, even with surgery. However, certain measures can be taken to prevent muscle shortening.

Unless accident victims die from their severe injuries, their life expectancy is by no means lower than that of healthy individuals. However, this may not be the case if they require mechanical ventilation. 

A spinal cord injury does not necessarily mean that a person is confined to a wheelchair and permanently dependent on others. The patient can participate in rehabilitation programs at specialized clinics. The goal of these programs is to strengthen the patient’s independence. With the help of a physical therapist, the patient learns to use their remaining intact muscles more effectively and to move limbs that are only partially paralyzed.

Patients can also learn to empty their bladder voluntarily through intensive abdominal muscle training. If this is not successful, patients can insert their own urinary catheter several times a day or live with a permanent urinary catheter that is replaced every four weeks.

Massages and physical exercises in water can help restore at least some of the lost sensation. In a special self-help group for people with spinal cord injuries, patients learn to cope better with their changed lives and no longer feel socially isolated.

What is paralysis from a medical perspective?

Paralysis is the inability to voluntarily move a muscle or group of muscles. It results from damage to the central or peripheral nervous system, such as in the brain or spinal cord.

What is the difference between complete and incomplete paralysis?

In complete paralysis, motor functions are completely lost. In incomplete paralysis, residual functions remain, such as minimal muscle strength or sensation.

What is paraplegia?

Spinal cord injury is a specific form of paralysis in which the spinal cord is damaged. Depending on the level of the lesion, the legs, arms, or all four limbs may be affected.

What causes can lead to paralysis?

Possible causes include stroke, tumors, infections, multiple sclerosis, trauma, or damage to the spinal cord. Disorders of the peripheral nervous system may also be a factor.

How is paralysis treated?

Treatment depends on the cause of the paralysis and often includes physical therapy, occupational therapy, medication, and, in some cases, surgery. The goal is to maintain mobility and improve daily functioning despite the paralysis.