A spinal cord injury (SCI) is damage to the

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spin ...

that causes temporary or permanent changes in its function. Symptoms may include loss of muscle function,

sensation Sensation (psychology) refers to the processing of the senses by the sensory system. Sensation or sensations may also refer to: In arts and entertainment In literature *Sensation (fiction), a fiction writing mode * Sensation novel, a Britis ...

, or autonomic function in the parts of the body served by the spinal cord below the level of the injury. Injury can occur at any level of the spinal cord and can be ''complete'', with a total loss of sensation and muscle function at lower sacral segments, or ''incomplete'', meaning some nervous signals are able to travel past the injured area of the cord up to the Sacral S4-5 spinal cord segments. Depending on the location and severity of damage, the symptoms vary, from

numbness Hypoesthesia or numbness is a common side effect of various medical conditions that manifests as a reduced sense of touch or sensation, or a partial loss of sensitivity to sensory stimuli. In everyday speech this is generally referred to as nu ...

paralysis Paralysis (also known as plegia) is a loss of motor function in one or more muscles. Paralysis can also be accompanied by a loss of feeling (sensory loss) in the affected area if there is sensory damage. In the United States, roughly 1 in 5 ...

, including bowel or bladder

incontinence Incontinence or Incontinent may refer to: * Fecal incontinence, the involuntary excretion of bowel contents * Urinary incontinence, the involuntary excretion of urine * Lack of moderation or self-control, especially related to sexual desire - see ...

. Long term outcomes also range widely, from full recovery to permanent

tetraplegia Tetraplegia, also known as quadriplegia, is defined as the dysfunction or loss of motor and/or sensory function in the cervical area of the spinal cord. A loss of motor function can present as either weakness or paralysis leading to partial or ...

(also called quadriplegia) or

paraplegia Paraplegia, or paraparesis, is an impairment in motor or sensory function of the lower extremities. The word comes from Ionic Greek () "half-stricken". It is usually caused by spinal cord injury or a congenital condition that affects the neu ...

. Complications can include

muscle atrophy Muscle atrophy is the loss of skeletal muscle mass. It can be caused by immobility, aging, malnutrition, medications, or a wide range of injuries or diseases that impact the musculoskeletal or nervous system. Muscle atrophy leads to muscle weakness ...

, loss of voluntary motor control,

spasticity Spasticity () is a feature of altered skeletal muscle performance with a combination of paralysis, increased tendon reflex activity, and hypertonia. It is also colloquially referred to as an unusual "tightness", stiffness, or "pull" of muscles ...

pressure sore Pressure ulcers, also known as pressure sores, bed sores or pressure injuries, are localised damage to the skin and/or underlying tissue that usually occur over a bony prominence as a result of usually long-term pressure, or pressure in combi ...

infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable d ...

s, and

breathing problem Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing dis ...

s. In the majority of cases the damage results from physical trauma such as car accidents,

gunshot wound A gunshot wound (GSW) is a penetrating injury caused by a projectile (e.g. a bullet) from a gun (typically firearm or air gun). Damages may include bleeding, bone fractures, organ damage, wound infection, loss of the ability to move pa ...

fall Autumn, also known as fall in American English and Canadian English, is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, in September ( Northern Hemisphere) or March ( Sout ...

s, or

sports injuries Sports injuries are injuries that occur during sport, athletic activities, or exercising. In the United States, there are approximately 30 million teenagers and children who participate in some form of organized sport. Of those, about three mi ...

, but it can also result from nontraumatic causes such as

, insufficient blood flow, and

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

s. Just over half of injuries affect the

cervical spine In tetrapods, cervical vertebrae (singular: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In sa ...

, while 15% occur in each of the

thoracic spine In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebrae and they are intermediate in size between the cervi ...

, border between the thoracic and

lumbar spine The lumbar vertebrae are, in human anatomy, the five vertebrae between the rib cage and the pelvis. They are the largest segments of the vertebral column and are characterized by the absence of the foramen transversarium within the transverse p ...

, and lumbar spine alone. Diagnosis is typically based on symptoms and medical imaging. Efforts to prevent SCI include individual measures such as using safety equipment, societal measures such as safety regulations in sports and traffic, and improvements to equipment. Treatment starts with restricting further motion of the spine and maintaining adequate

blood pressure Blood pressure (BP) is the pressure of circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term "blood pressur ...

Corticosteroids Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are in ...

have not been found to be useful. Other interventions vary depending on the location and extent of the injury, from bed rest to surgery. In many cases, spinal cord injuries require long-term

physical Physical may refer to: *Physical examination In a physical examination, medical examination, or clinical examination, a medical practitioner examines a patient for any possible medical signs or symptoms of a medical condition. It generally cons ...

and

occupational therapy Occupational therapy (OT) is a global healthcare profession. It involves the use of assessment and intervention to develop, recover, or maintain the meaningful activities, or ''occupations'', of individuals, groups, or communities. The field o ...

, especially if it interferes with

activities of daily living Activity may refer to: * Action (philosophy), in general * Human activity: human behavior, in sociology behavior may refer to all basic human actions, economics may study human economic activities and along with cybernetics and psychology may st ...

. In the United States, about 12,000 people a year survive a spinal cord injury. The most commonly affected group are

young adult A young adult is generally a person in the years following adolescence. Definitions and opinions on what qualifies as a young adult vary, with works such as Erik Erikson's stages of human development significantly influencing the definition of ...

males. SCI has seen great improvements in its care since the middle of the 20th century. Research into potential treatments includes

stem cell In multicellular organisms, stem cells are undifferentiated or partially differentiated cells that can differentiate into various types of cells and proliferate indefinitely to produce more of the same stem cell. They are the earliest type of ...

implantation, hypothermia, engineered materials for tissue support,

epidural Epidural administration (from Ancient Greek ἐπί, , upon" + ''dura mater'') is a method of medication administration in which a medicine is injected into the epidural space around the spinal cord. The epidural route is used by physicians an ...

spinal stimulation Neurostimulation is the purposeful modulation of the nervous system's activity using invasive (e.g. microelectrodes) or non-invasive means (e.g. transcranial magnetic stimulation or transcranial electric stimulation, tES, such as tDCS or transcr ...

, and wearable

robotic exoskeleton A powered exoskeleton, also known as power armor, powered armor, powered suit, cybernetic suit, cybernetic armor, exosuit, hardsuit, exoframe or augmented mobility, is a mobile machine that is wearable over all or part of the human body, provi ...

Classification

Spinal cord injury can be traumatic or nontraumatic, and can be classified into three types based on cause: mechanical forces, toxic, and

ischemic Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems ...

(from lack of blood flow). The damage can also be divided into

primary and secondary injury Primary and secondary brain injury are ways to classify the injury processes that occur in brain injury. In traumatic brain injury (TBI), primary brain injury occurs during the initial insult, and results from displacement of the physical structu ...

: the cell death that occurs immediately in the original injury, and

biochemical cascade A biochemical cascade, also known as a signaling cascade or signaling pathway, is a series of chemical reactions that occur within a biological cell when initiated by a stimulus. This stimulus, known as a first messenger, acts on a receptor that ...

s that are initiated by the original insult and cause further tissue damage. These secondary injury pathways include the

ischemic cascade The ischemic (ischaemic) cascade is a series of biochemical reactions that are initiated in the brain and other aerobic tissues after seconds to minutes of ischemia (inadequate blood supply). This is typically secondary to stroke, injury, or card ...

inflammation Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...

swelling Swelling may refer to: *Edema, a transient abnormal enlargement of a body part or area not caused by a tumor *Die swell, the increase in cross-sectional area of a polymer after it exits an extrusion die *Swelling capacity, the amount of liquid that ...

, cell suicide, and

neurotransmitter A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell. Neur ...

imbalances. They can take place for minutes or weeks following the injury. At each level of the spinal column, spinal nerves branch off from either side of the spinal cord and exit between a pair of

vertebra The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characterist ...

e, to inner