Spinal Cord Injury Journal

What Is a Spinal Shock? Symptoms, Causes and How Long it Lasts

Written by Spinal Cord Team | February 07, 2020

If you or a loved one has recently suffered a spinal cord injury (SCI), you may be hearing a lot of unfamiliar terms from doctors. One medical term that many people only hear about after suffering an SCI is "spinal shock." What shock in this context? More importantly, how can this medical condition be treated?

What Is Spinal Shock/Spinal Shock Syndrome?

Spinal shock is characterized by the temporary reduction or loss of reflexes following a spinal cord injury. The spinal cord, which is comprised of bundles of delicate nerves encased within a protective column of vertebrae, serves as the communication superhighway for your brain to transmit signals to the rest of your body.

When the spinal cord is injured, there may be a permanent or temporary loss of activity and sensation below the level of the injury. In general, the more severe the injury, the worse the autonomic dysfunction will be. However, spinal shock alone cannot be used to determine your medical prognosis or assess the severity of a spinal cord injury.

Spinal shock syndrome is really a combination of various reflex and neurological concerns, including hyporeflexia (the condition of sub-standard or absent reflexes) and autonomic dysfunction. Autonomic dysfunction refers to problems with the autonomic nervous system which controls the ‘automatic’ things your body does such as maintaining your blood pressure and heart rate.

Spinal shock is closely related to another form of shock called neurogenic shock. Both conditions have similar causes, but have different effects. As noted in a ScienceDirect topic page, “Neurogenic shock describes the hemodynamic changes resulting from a sudden loss of autonomic tone due to spinal cord injury. Spinal shock, on the other hand, refers to a loss of all sensation below the level of injury and is not circulatory in nature.”

Spinal Shock Anatomy and Pathophysiology

Understanding the pathophysiology – defined by Merriam-Webster as “the functional changes that accompany a particular syndrome or disease” – in spinal shock cases can be aided by understanding the anatomy of the spinal cord.

The spinal cord and its nerve bundles can be broken down into four major sections:

  • The Cervical Spinal Cord. This is the uppermost section of the spinal cord where the brain connects to the rest of the nervous system. This part of the spinal cord is contained in the cervical vertebrae (labeled C1-C7, with an extra section of cord labeled C8 located between the C7 vertebra and the T1 vertebra).
  • The Thoracic Spinal Cord. This section of the spinal cord is located in the upper back and is contained within the thoracic vertebrae (Labeled T1-T12).
  • The Lumbar Spinal Cord. The section of the spinal cord contained in the lower back. The lumbar spinal vertebrae (labeled L1-L5) actually contain the end of the spinal cord proper.
  • The Sacral Spine. While the spinal cord ends in the lumbar spine, there are spinal nerve bundles located in the sacral spine – which is the lower, triangle-shaped bone structure at the base of the spine consisting of five vertebrae – several of which are fused together.

Damage to different levels of the spinal cord will have different effects. Generally speaking, the higher up on the spinal cord an injury (i.e., the closer to the brain it is), the worse the effects will be.

What Happens after a Spinal Shock?

After a spinal shock, the spinal cord enters either hyporeflexia – a significant reduction in reflexes – or areflexia – the temporary loss of reflexes. Because reflexes help to prevent harm, their temporary loss can be dangerous. More importantly, since most SCI survivors are hospitalized in a safe environment following their injuries, the loss of reflexes signals serious spinal functioning issues.

In the hours immediately following a spinal shock, SCI survivors might not even realize that they are in spinal shock. Other, more urgent injuries are typically a higher priority.

Stages/Phases of Spinal Shock

According to research by Dr. Dittuno of Thomas Jefferson University, there are four stages to spinal shock. Early stages often begin with patients experiencing an “anaesthetized feeling” of the body below the injury, however this can be tricky to determine as only a day following injury, the extent of injury is still being assessed – and the application of actual anesthesia during treatment immediately after an injury can further confuse the early stages of spinal shock.

  1. One to two days following the injury: Nerve cells become less responsive to sensory input, resulting in full or partial loss of spinal cord reflexes. This is known as hyporeflexia.
  2. One to three days following injury: Initial return of some reflexes. Polysynaptic reflexes — those that require a signal to travel from a sensory neuron to a motor neuron — tend to return first. The delayed plantar reflex, a variation of the normal plantar reflex common among SCI survivors, typically returns first. Next is the bulbocavernosus reflex, which causes the anal sphincter to tighten in response to squeezing the clitoris or head of the penis. Many doctors test for the bulbocavernosus reflex to assess spinal cord injuries.
  3. One to four weeks following the injury: Hyperreflexia, a pattern of unusually strong reflexes, occurs. This is the result of new nerve synapse growth, and is normally temporary.
  4. One to twelve months following the injury: Hyperreflexia continues, and spasticity may develop. This process is due to changes in the neuronal cell bodies, and takes much longer than the other stages.

So, how can you tell whether you have spinal shock? Spinal shock is characterized by a variety of symptoms and everyone experiences their SCI differently. This fact makes it difficult for doctors to differentiate spinal shock symptoms from those that result directly from the spinal cord injury itself.

Symptoms of Spinal Shock

Below is a list of some symptoms that may accompany the different stages of spinal shock. Of course, it can be challenging for doctors to determine whether or not they are looking to treat spinal shock or if they’re looking at issues created directly from the spinal cord injury. Spinal shock is characterized by:

  • Altered body temperature
  • Skin color and moisture changes (such as dry and pale skin)
  • Abnormal perspiration function (decreased or increased sweating, flushing)
  • Increased blood pressure and slowed heart rate
  • Irregularities in the musculoskeletal system
  • Altered sensory response
  • Unusual urinary bladder and GI tract functions (overflow and incontinence)
  • Irregular vasomotor response
  • Depressed genital reflexes

All patients of spinal cord injury, and spinal shock, will experience it differently. Although there are general symptoms (such as those listed above), you cannot predict the kind of reaction an individual’s body will take following a spinal cord injury.

In the first few days following an SCI, doctors will be keeping a close eye on the patient so they can evaluate if any symptoms are demonstrative of spinal shock or are due to the injury itself. Spinal shock death is rare, and most deaths among spinal shock patients is caused by the original injury rather than the condition.

What Causes Spinal Shock?

Just as your body goes into a state of shock after a life-threatening injury, your spinal cord goes into a state of shock after an injury. Almost all people with spinal cord injuries experience some degree of spinal shock, but the severity tends to be greater when the spinal cord is severed, or when it is extremely swollen.

Differential Diagnoses of Spinal Shock

A “differential diagnosis” is a list of possible conditions that may be causing the specific symptoms that a person is experiencing. Doctors may provide their patients with a list of differential diagnoses for a condition based on things like:

  • Presence or absence of specific symptoms commonly associated with the disease/condition;
  • Presence of symptoms not normally associated with the condition;
  • Whether there are triggers for any symptoms;
  • Medical history (personal and familial) that may make someone susceptible to specific conditions;
  • Medications or recreational substances the patient uses frequently; and
  • Recent major events (such as accidents, loss of a job, introduction of a new pet, etc.) that can cause injury, stress, or a significant change in environment.

Doctors may try to identify differential diagnoses by performing some tests in controlled conditions. This way, they can verify if there are specific triggers for symptoms that are more in line with a differential diagnosis other than spinal shock.

Some examples of differential diagnoses for spinal shock symptoms include:

  • Urinary Tract Infections (UTIs). Changes in bladder or bowel function may be caused by infections of those bodily systems rather than spinal shock from an SCI.
  • Melanoma and Skin Infections. Melanoma or some skin infections may cause changes in skin color and skin moisture.
  • Malnutrition (Mild to Severe). Improper nutrition can cause a broad range of symptoms, including abnormal muscle function, altered sensory function, and unusual heart rate or blood pressure (among other things).

This is just a small sample of the differential diagnoses that share one or more symptoms with spinal shock—there are many more conditions than could be listed in a short article.

How Do Doctors Separate Spinal Shock from Other Conditions?

In many cases, the identification of spinal shock as a separate condition from other potential diagnoses is based on a close examination of the patient and taking into account when the symptoms appeared—such as them only appearing within a day of the patient being in a major auto accident or suffering a slip and fall incident.

How Long Does Spinal Shock Last?

Spinal shock is a short-lived phenomenon, and can be divided into specific, predictable stages. It can start roughly 30 minutes after an injury, and last six weeks (though spinal shock duration can vary from this in some cases).

While spinal shock is typically characterized by being temporary, it can be permanent in a few cases. This may be why some people think that spinal shock is a permanent loss of some of the spinal cord’s functions rather than a temporary condition (permanent loss is usually caused by an SCI or brain injury).

How Do I Know When Spinal Shock is Over?

It can be difficult for some spinal shock patients to know exactly when their condition is “over” and they can be considered as fully recovered as they can be. In some cases, spinal shock signs and symptoms never fully go away.

Generally speaking, a doctor should be the one to provide the official “all clear” to let a patient know that their condition is over. However, different doctors/physicians may use different criteria to judge that the condition has ended.

According to a study featured on the U.S. National Library of Medicine National Institutes of Health, “Some clinicians interpret spinal shock as ending with the appearance of the bulbocavernosus reflex… Others state that spinal shock ends with the recovery of deep tendon reflexes.”

Spinal Shock Treatment

Spinal shock is to spinal cord injuries as fevers are to infections. Spinal shock is merely a symptom of an underlying problem, not a disease itself. Spinal shock is not typically dangerous, and other symptoms of SCI are far more likely to cause serious, lasting physiological issues. Treatments for spinal cord injury-related spinal shock include:

  • Physical and occupational therapies.
  • Exercise therapy to strengthen muscles and maintain a healthy body weight.
  • Medications such as painkillers, antibiotics, and antidepressants.
  • Psychotherapy to aid in coping with and managing the injury.
  • Family education to help your loved ones understand your injuries.
  • Use of supportive or assistive technologies, such as a wheelchair or an artificial respirator.
  • Support groups to help you meet and learn from others’ experiences that can serve as a resource.

All patients of spinal cord injury, and spinal shock, will experience it differently. Although there are general symptoms (such as those listed previously), you cannot predict the kind of reaction an individual’s body will take following a spinal cord injury.

Consequently, treatment for spinal shock tends to focus on treating the spinal cord injury as a whole. In the immediate aftermath of a spinal cord injury, treatment may include:

  • Surgery to remove bone fragments or items lodged in the spinal cord.
  • Spinal fusion surgery.
  • Various brain and spinal cord imaging tests, as well as functional tests such as assessments of reflexes, cognition, and motor skills.
  • Antibiotics to treat or prevent infections.
  • Assisted respiration.
  • Planning for release to a rehabilitation facility.
  • Mental health counseling.

Spinal cord injuries vary greatly from person to person, and can change in response to physical therapy. Moreover, it’s difficult to predict the prognosis until swelling diminishes. Thus the early days of treatment center around stabilization, future planning, and adjustment to the shock of a SCI.

Spinal Shock Complications

The complications of spinal shock can be similar to SCI complications since SCIs are a common cause of spinal shock – spinal shock itself is listed as a complication of SCI. Some complications that can arise from spinal shock include:

  • Loss of muscle control and inability to balance because of the loss of sensation below the injury site;
  • Hyperreflexia as synapse growth ensues;
  • Spasticity (again because of synapse growth or abnormalities in connections of the nervous system to affected muscle groups);
  • Depression caused by various neurological and environmental factors; and
  • Urinary tract infections from irregularities in bowel and bladder function.

Prognosis of Spinal Shock

Spinal shock tends to follow predictable patterns — though no specific treatment is deemed necessary above others. The presence of spinal shock, however, suggests a serious spinal cord injury. Yet, it should be noted that the severity of the spinal shock is not a good gauge for either the severity or the prognosis of the spinal cord injury.

Spinal cord injuries tend to change over time. The more severely compressed the spinal cord is, the less likely full recovery will be. If the spinal cord is severed, full recovery is extremely unlikely. The location of the injury is also a good indicator of prognosis. The lower the injury is, the less severe the mobility and other impairments will be.

Neurogenic Shock: A Related Condition

In people who suffer spinal cord injuries above their thoracic nerves (specifically above the T6 nerve), neurogenic shock can occur. Neurogenic shock can also be caused by disruptions in the autonomic system. Because the autonomic nervous system regulates automatic functions such as heart rate, low blood pressure and slowed heart rate can occur.

Left untreated, neurogenic shock can cause organ failure, proving fatal. A variety of drugs, including vasopressin and dopamine, may reduce the effects of neurogenic shock. Assistive respiration devices, heart monitoring, and other tools may also be necessary until neurogenic shock is well-controlled.

Spinal shock and neurogenic shock often co-occur. While spinal shock resolves on its own, neurogenic shock is a medical emergency.

Living with a spinal cord injury is something that you don’t have to do alone. There are hundreds of thousands of people in the U.S. living with spinal cord injuries. We have an online community of SCI injury survivors and family members you can connect with to discuss your injuries, share experiences, and share helpful coping tips or information.