A self-inflicted wound (SIW), is the act of harming oneself where there are no underlying psychological problems related to the self-injury, but where the injurer wanted to take advantage of being injured.

A gunshot wound (GSW) is a form of physical trauma sustained from the discharge of arms or munitions. The most common forms of ballistic trauma stem from firearms used in armed conflicts, civilian sporting, recreational pursuits and criminal activity. Ballistic trauma can be fatal or cause long-term consequences.

The degree of tissue disruption caused by a projectile is related to the size of the temporary versus permanent cavity it creates as it passes through tissue. The extent of cavitation, in turn, is related to the following characteristics of the projectile:

- Kinetic energy: KE = 1/2"mv" (where "m" is mass and "v" is velocity). This helps to explain why wounds produced by missiles of higher mass and/or higher velocity produce greater tissue disruption than missiles of lower mass and velocity.

- Impulse: IMP = "mv". The impulse is working in a couple with kinetic energy, featuring the same characteristics

- Yaw

- Deformation

- Fragmentation

The immediate damaging effect of a gunshot wound is typically severe bleeding, and with it the potential for hypovolemic shock, a condition characterized by inadequate delivery of oxygen to vital organs. In the case of traumatic hypovolemic shock, this failure of adequate oxygen delivery is due to blood loss, as blood is the means of delivering oxygen to the body's constituent parts. Devastating effects can result when a bullet strikes a vital organ such as the heart or lungs, or damages a component of the central nervous system such as the spine or brain.

Common causes of death following gunshot injury include exsanguination, hypoxia caused by pneumothorax, catastrophic injury to the heart and larger blood vessels, and damage to the brain or central nervous system. Additionally, gunshot wounds typically involve a large degree of nearby tissue disruption and destruction due to the physical effects of the projectile. Non-fatal gunshot wounds frequently have severe and long-lasting effects, typically some form of major disfigurement and/or permanent disability.

Gunshot injuries can vary widely from case to case since the location of the injury can be in any part of the body, with wide variations in entry point. Also, the path and possible fragmentation of the bullet within the body is unpredictable. The study of the dynamics of bullets in gunshot injuries is called terminal ballistics.

As a rule, all gunshot wounds are considered medical emergencies that require immediate treatment. Hospitals are generally required to report all gunshot wounds to police.

Psychological trauma is a type of damage to the mind that occurs as a result of a severely distressing event. Trauma is often the result of an overwhelming amount of stress that exceeds one's ability to cope, or integrate the emotions involved with that experience. A traumatic event involves one's experience, or repeating events of being overwhelmed that can be precipitated in weeks, years, or even decades as the person struggles to cope with the immediate circumstances, eventually leading to serious, long-term negative consequences.

However, trauma differs between individuals, according to their subjective experiences. People will react to similar events differently. In other words, not all people who experience a potentially traumatic event will actually become psychologically traumatized. However, it is possible to develop posttraumatic stress disorder (PTSD) after being exposed to a potentially traumatic event.

This discrepancy in risk rate can be attributed to protective factors some individuals may have that enable them to cope with trauma; they are related to temperamental and environmental factors. Some examples are mild exposure to stress early in life, resilience characteristics, and active seeking of help.

Eighty percent of self-harm involves stabbing or cutting the skin with a sharp object. However, the number of self-harm methods are only limited by an individual's inventiveness and their determination to harm themselves; this includes burning, self-poisoning, alcohol abuse, self-embedding of objects, hair pulling, bruising/hitting one's self, scratching to hurt one's self, knowingly abusing over the counter or prescription drugs, and forms of self-harm related to anorexia and bulimia. The locations of self-harm are often areas of the body that are easily hidden and concealed from the detection of others. As well as defining self-harm in terms of the act of damaging the body, it may be more accurate to define self-harm in terms of the intent, and the emotional distress that the person is attempting to deal with. Neither the DSM-IV-TR nor the ICD-10 provide diagnostic criteria for self-harm. It is often seen as only a symptom of an underlying disorder, though many people who self-harm would like this to be addressed.

Common signs that a person may be engaging in self harm include the following: they ensure that are always harmful objects close by, they are experiencing difficulties in their personal relationships, their behaviour becomes unpredictable, they question their worth and identity, they make statements that display helplessness and hopelessness.

Self-harm (SH), also referred to as "self-injury" (SI), "self-inflicted violence" (SIV), "nonsuicidal self injury" (NSSI) or "self-injurious behaviour" (SIB), refers to a spectrum of behaviours where demonstrable injury is self-inflicted. The behaviour involves deliberate tissue damage that is usually performed without suicidal intent. The most common form of self-harm involves cutting of the skin using a sharp object, e. g. a knife or razor blade. The term "self-mutilation" is also sometimes used, although this phrase evokes connotations that some find worrisome, inaccurate, or offensive. "Self-inflicted wounds" is a specific term associated with soldiers to describe non-lethal injuries inflicted in order to obtain early dismissal from combat. This differs from the common definition of self-harm, as damage is inflicted for a specific secondary purpose. A broader definition of self-harm might also include those who inflict harm on their bodies by means of disordered eating.

Nonsuicidal self injury has been listed as a new disorder in the DSM-5 under the category "Conditions for Further Study". This disorder occurs when a person is deliberately harming themselves in a physical way without the intent of committing suicide. Self-harm without suicidal intent can be seen on a spectrum, just like many other disorders (substance abuse, gambling addiction). Just like these other disorders, once the self harming behaviours cross a certain threshold, it then becomes classified as a mental health disorder. Criteria for NSSI include five or more days of self-inflicted harm over the course of one year without suicidal intent, and the individual must have been motivated by seeking relief from a negative state, resolving an interpersonal difficulty, or achieving a positive state.

A common belief regarding self-harm is that it is an attention-seeking behaviour; however, in many cases, this is inaccurate. Many self-harmers are very self-conscious of their wounds and scars and feel guilty about their behaviour, leading them to go to great lengths to conceal their behaviour from others. They may offer alternative explanations for their injuries, or conceal their scars with clothing. Self-harm in such individuals may not be associated with suicidal or para-suicidal behaviour. People who self-harm are not usually seeking to end their own life; it has been suggested instead that they are using self-harm as a coping mechanism to relieve emotional pain or discomfort or as an attempt to communicate distress. Alternatively, interpretations based on the supposed lethality of a self-harm may not give clear indications as to its intent: life risking behaviour may have no suicidal intent, whilst seemingly superficial cuts may have been a suicide attempt.

Studies of individuals with developmental disabilities (such as intellectual disability) have shown self-harm being dependent on environmental factors such as obtaining attention or escape from demands. Some individuals may have dissociation harboring a desire to feel real or to fit into society's rules.

People who go through these types of extremely traumatic experiences often have certain symptoms and problems afterward. The severity of these symptoms depends on the person, the type of trauma involved, and the emotional support they receive from others. Reactions to and symptoms of trauma can be wide and varied, and differ in severity from person to person. A traumatized individual may experience one or several of them.

After a traumatic experience, a person may re-experience the trauma mentally and physically, hence trauma reminders, also called triggers, can be uncomfortable and even painful. It can damage people’s sense of safety, self, self-efficacy, as well as the ability to regulate emotions and navigate relationships. They may turn to psychoactive substances including alcohol to try to escape or dampen the feelings. These triggers cause flashbacks, which are dissociative experiences where the person feels as though the events is reoccurring. They can range from distracting to complete dissociation or loss of awareness of the current context. Re-experiencing symptoms are a sign that the body and mind are actively struggling to cope with the traumatic experience.

Triggers and cues act as reminders of the trauma, and can cause anxiety and other associated emotions. Often the person can be completely unaware of what these triggers are. In many cases this may lead a person suffering from traumatic disorders to engage in disruptive or self-destructive coping mechanisms, often without being fully aware of the nature or causes of their own actions. Panic attacks are an example of a psychosomatic response to such emotional triggers.

Consequently, intense feelings of anger may frequently surface, sometimes in inappropriate or unexpected situations, as danger may always seem to be present, as much as it is actually present and experienced from past events. Upsetting memories such as images, thoughts, or flashbacks may haunt the person, and nightmares may be frequent. Insomnia may occur as lurking fears and insecurity keep the person vigilant and on the lookout for danger, both day and night. Trauma doesn't only cause changes in one's daily functions but could also lead to morphological changes. Such epigenetic changes can be passed on to the next generations, thus making genetics as one of the components of the causes of psychological trauma. However, some people are born with or later develop protective factors such as genetics and sex that help lower their risk of psychological trauma.

The person may not remember what actually happened, while emotions experienced during the trauma may be re-experienced without the person understanding why (see Repressed memory). This can lead to the traumatic events being constantly experienced as if they were happening in the present, preventing the subject from gaining perspective on the experience. This can produce a pattern of prolonged periods of acute arousal punctuated by periods of physical and mental exhaustion. This can lead to mental health disorders like acute stress and anxiety disorder, traumatic grief, undifferentiated somatoform disorder, conversion disorders, brief psychotic disorder, borderline personality disorder, adjustment disorder...etc.

In time, emotional exhaustion may set in, leading to distraction, and clear thinking may be difficult or impossible. Emotional detachment, as well as dissociation or "numbing out", can frequently occur. Dissociating from the painful emotion includes numbing all emotion, and the person may seem emotionally flat, preoccupied, distant, or cold. Dissociation includes depersonalisation disorder, dissociative amnesia, dissociative fugue, dissociative identity disorder, etc. Exposure to and re-experiencing trauma can cause neurophysiological changes like slowed myelination, abnormalities in synaptic pruning, shrinking of the hippocampus, cognitive and affective impairment. This is significant in brain scan studies done regarding higher order function assessment with children and youth who were in vulnerable environments.

Some traumatized people may feel permanently damaged when trauma symptoms do not go away and they do not believe their situation will improve. This can lead to feelings of despair, transient paranoid ideation, loss of self-esteem, profound emptiness, suicidality, and frequently depression. If important aspects of the person's self and world understanding have been violated, the person may call their own identity into question. Often despite their best efforts, traumatized parents may have difficulty assisting their child with emotion regulation, attribution of meaning, and containment of post-traumatic fear in the wake of the child's traumatization, leading to adverse consequences for the child. In such instances, it is in the interest of the parent(s) and child for the parent(s) to seek consultation as well as to have their child receive appropriate mental health services.

Strangling is compression of the neck that may lead to unconsciousness or death by causing an increasingly hypoxic state in the brain. Fatal strangling typically occurs in cases of violence, accidents, and is one of two main ways that hanging may cause death (alongside breaking the victim's neck).

Strangling does not have to be fatal; limited or interrupted strangling is practised in erotic asphyxia, in the choking game, and is an important technique in many combat sports and self-defence systems.

Strangling can be divided into three general types according to the mechanism used:

- Hanging—Suspension from a cord wound around the neck

- Ligature strangulation—Strangulation without suspension using some form of cord-like object called a garrote

- Manual strangulation—Strangulation using the fingers or other extremity

The characteristics of a burn depend upon its depth. Superficial burns cause pain lasting two or three days, followed by peeling of the skin over the next few days. Individuals suffering from more severe burns may indicate discomfort or complain of feeling pressure rather than pain. Full-thickness burns may be entirely insensitive to light touch or puncture. While superficial burns are typically red in color, severe burns may be pink, white or black. Burns around the mouth or singed hair inside the nose may indicate that burns to the airways have occurred, but these findings are not definitive. More worrisome signs include: shortness of breath, hoarseness, and stridor or wheezing. Itchiness is common during the healing process, occurring in up to 90% of adults and nearly all children. Numbness or tingling may persist for a prolonged period of time after an electrical injury. Burns may also produce emotional and psychological distress.

Strangling involves one or several mechanisms that interfere with the normal flow of oxygen into the brain:

- Compression of the carotid arteries or jugular veins—causing cerebral ischemia.

- Compression of the laryngopharynx, larynx, or trachea—causing asphyxia.

- Stimulation of the carotid sinus reflex—causing bradycardia, hypotension, or both.

Depending on the particular method of strangulation, one or several of these typically occur in combination; vascular obstruction is usually the main mechanism. Complete obstruction of blood flow to the brain is associated with irreversible neurological damage and death, but during strangulation there is still unimpeded blood flow in the vertebral arteries. Estimates have been made that significant occlusion of the carotid arteries and jugular veins occurs with a pressure of around , while the trachea demands six times more at approximately .

As in all cases of strangulation, the rapidity of death can be affected by the susceptibility to carotid sinus stimulation. Carotid sinus reflex death is sometimes considered a mechanism of death in cases of strangulation, but it remains highly disputed. The reported time from application to unconsciousness varies from 7–14 seconds if effectively applied to one minute in other cases, with death occurring minutes after unconsciousness.

A number of complications may occur, with infections being the most common. In order of frequency, potential complications include: pneumonia, cellulitis, urinary tract infections and respiratory failure. Risk factors for infection include: burns of more than 30% TBSA, full-thickness burns, extremes of age (young or old), or burns involving the legs or perineum. Pneumonia occurs particularly commonly in those with inhalation injuries.

Anemia secondary to full thickness burns of greater than 10% TBSA is common. Electrical burns may lead to compartment syndrome or rhabdomyolysis due to muscle breakdown. Blood clotting in the veins of the legs is estimated to occur in 6 to 25% of people. The hypermetabolic state that may persist for years after a major burn can result in a decrease in bone density and a loss of muscle mass. Keloids may form subsequent to a burn, particularly in those who are young and dark skinned. Following a burn, children may have significant psychological trauma and experience post-traumatic stress disorder. Scarring may also result in a disturbance in body image. In the developing world, significant burns may result in social isolation, extreme poverty and child abandonment.

Most self-inflicted wounds occur during wartime, for various possible reasons.

Potential draftees may self-injure in order to avoid being drafted for health reasons. This was practiced as Abstinence (conscription) by some Jewish conscripts in the Russian Empire.

The most common reason enlisted soldiers self-wound is to render themselves unable to continue serving in combat, thus resulting in their removal from the combat line to a hospital. Thus, self-injury can be used to avoid a more serious combat injury or a combat death.

In prisons and forced labour camps people sometimes self-injure so that they will not be forced to work and could spend some time in the more comfortable conditions of the barracks.

On 22 July 2016, a shooting occurred in the vicinity of the Olympia shopping mall in the Moosach district of Munich, Germany. Ten people, including the perpetrator, were killed and 36 others were injured. The shooting took place at a McDonald's restaurant near the shopping mall, in front of a Saturn electronics store nearby, and in the mall itself. The gunman, later identified as 18-year-old David Sonboly, died nearby from a self-inflicted gunshot wound to the head. His motive for the shooting is under investigation.

An aerosol burn is an injury to the skin caused by the pressurized gas within an aerosol spray cooling quickly, with the sudden drop in temperature sufficient to cause frostbite to the applied area. Medical studies have noted an increase of this practice, known as "frosting", in pediatric and teenage patients.

Adiabatic expansion causes the gas (with a low boiling temperature) to rapidly cool on exit from the aerosol applier. According to controlled laboratory experiments, the gas from a typical deodorant spray can reduce skin temperature by up to sixty degrees Celsius.

The form of injury is freezing of the skin, a type of frostbite. It is highly advised for those who suffer from frostbite to seek medical attention.

In rare cases aerosol-induced burns can be severe enough to necessitate skin grafting.

The history of a centipede bite is fairly straightforward; the victim typically sees and identifies the characteristic centipede before, or soon after being bitten.

Symptoms which are most likely to develop include:

- severe pain, which is usually in proportion to the size of the centipede

- swelling and redness. Possible 'bullseye'

- skin necrosis

- swollen, painful lymph nodes in the regions of the bitten limb

- headache

- palpitations or a racing pulse

- nausea and vomiting

- anxiety

- local itching and burning sensations

The wound left by the bite may be accompanied by swelling, redness, and small puncture wounds which may form a circular pattern. This wound may be susceptible to local ulcerations and necrosis.

A severe bite from a large centipede on a child, senior or person with a weakened heart can cause heart attack if untreated. This is exceptionally rare.

A contusion, commonly known as a bruise, is a type of hematoma of tissue in which capillaries and sometimes venules are damaged by trauma, allowing blood to seep, hemorrhage, or extravasate into the surrounding interstitial tissues. The bruise then remains visible until the blood is either absorbed by tissues or cleared by immune system action. Bruises, which do not blanch under pressure, can involve capillaries at the level of skin, subcutaneous tissue, muscle, or bone. Bruises are not to be confused with other similar-looking lesions primarily distinguished by their diameter or causation. These lesions include petechia (1 cm caused by blood dissecting through tissue planes and settled in an area remote from the site of trauma or pathology such as periorbital ecchymosis, e.g.,"raccoon eyes", arising from a basilar skull fracture or from a neuroblastoma).

As a type of hematoma, a bruise is always caused by internal bleeding into the interstitial tissues which does not break through the skin, usually initiated by blunt trauma, which causes damage through physical compression and deceleration forces. Trauma sufficient to cause bruising can occur from a wide variety of situations including accidents, falls, and surgeries. Disease states such as insufficient or malfunctioning platelets, other coagulation deficiencies, or vascular disorders, such as venous blockage associated with severe allergies can lead to the formation of purpura which is not to be confused with trauma-related bruising/contusion. If the trauma is sufficient to break the skin and allow blood to escape the interstitial tissues, the injury is not a bruise but instead a different variety of hemorrhage called bleeding. However, such injuries may be accompanied by bruising elsewhere.

Bruises often induce pain, but small bruises are not normally dangerous alone. Sometimes bruises can be serious, leading to other more life-threatening forms of hematoma, such as when associated with serious injuries, including fractures and more severe internal bleeding. The likelihood and severity of bruising depends on many factors, including type and healthiness of affected tissues. Minor bruises may be easily recognized in people with light skin color by characteristic blue or purple appearance (idiomatically described as "black and blue") in the days following the injury.

The presence of bruises may be seen in patients with platelet or coagulation disorders, or those who are being treated with an anticoagulant. Unexplained bruising may be a warning sign of child abuse, domestic abuse, or serious medical problems such as leukemia or meningoccocal infection. Unexplained bruising can also indicate internal bleeding or certain types of cancer. Long-term glucocorticoid therapy can cause easy bruising. Bruising present around the navel (belly button) with severe abdominal pain suggests acute pancreatitis. Connective tissue disorders such as Ehlers-Danlos syndrome may cause relatively easy or spontaneous bruising depending on the severity.

During an autopsy, bruises accompanying abrasions indicate the abrasions occurred while the individual was alive, as opposed to damage incurred post mortem.

The diagnosis of PTSD was originally developed for adults who had suffered from a single event trauma, such as rape, or a traumatic experience during a war. However, the situation for many children is quite different. Children can suffer chronic trauma such as maltreatment, family violence, and a disruption in attachment to their primary caregiver. In many cases, it is the child's caregiver who caused the trauma. The diagnosis of PTSD does not take into account how the developmental stages of children may affect their symptoms and how trauma can affect a child’s development.

The term developmental trauma disorder (DTD) has also been suggested. This developmental form of trauma places children at risk for developing psychiatric and medical disorders. Bessel van der Kolk explains DTD as numerous encounters with interpersonal trauma such as physical assault, sexual assault, violence or death. It can also be characterized by subjective events like betrayal, defeat or shame.

Repeated traumatization during childhood leads to symptoms that differ from those described for PTSD. Cook and others describe symptoms and behavioural characteristics in seven domains:

- "Attachment" – "problems with relationship boundaries, lack of trust, social isolation, difficulty perceiving and responding to others' emotional states"

- "Biology" – "sensory-motor developmental dysfunction, sensory-integration difficulties, somatization, and increased medical problems"

- "Affect or emotional regulation" – "poor affect regulation, difficulty identifying and expressing emotions and internal states, and difficulties communicating needs, wants, and wishes"

- "Dissociation" – "amnesia, depersonalization, discrete states of consciousness with discrete memories, affect, and functioning, and impaired memory for state-based events"

- "Behavioural control" – "problems with impulse control, aggression, pathological self-soothing, and sleep problems"

- "Cognition" – "difficulty regulating attention, problems with a variety of 'executive functions' such as planning, judgement, initiation, use of materials, and self-monitoring, difficulty processing new information, difficulty focusing and completing tasks, poor object constancy, problems with 'cause-effect' thinking, and language developmental problems such as a gap between receptive and expressive communication abilities."

- "Self-concept" – "fragmented and disconnected autobiographical narrative, disturbed body image, low self-esteem, excessive shame, and negative internal working models of self".

Complex post-traumatic stress disorder (C-PTSD; also known as complex trauma disorder) is a psychological disorder thought to occur as a result of repetitive, prolonged trauma involving harm or abandonment by a caregiver or other interpersonal relationships with an uneven power dynamic. C-PTSD is associated with sexual, emotional or physical abuse or neglect in childhood, intimate partner violence, victims of kidnapping and hostage situations, indentured servants, victims of slavery, sweatshop workers, prisoners of war, victims of bullying, concentration camp survivors, and defectors of cults or cult-like organizations. Situations involving captivity/entrapment (a situation lacking a viable escape route for the victim or a perception of such) can lead to C-PTSD-like symptoms, which include prolonged feelings of terror, worthlessness, helplessness, and deformation of one's identity and sense of self.

Some researchers argue that C-PTSD is distinct from, but similar to PTSD, somatization disorder, dissociative identity disorder, and borderline personality disorder, with the main distinction being that it distorts a person's core identity, especially when prolonged trauma occurs during childhood development . It was first described in 1992 by Judith Herman in her book "Trauma & Recovery" and an accompanying article. Though peer-reviewed journals have published papers on C-PTSD, the category is not yet adopted by either the American Psychiatric Association's (APA) "Diagnostic and Statistical Manual of Mental Disorders", 5th Edition (DSM-5), or in the World Health Organization's (WHO) "International Statistical Classification of Diseases and Related Health Problems", 10th Edition (ICD-10). However, it is proposed for the ICD-11, to be finalized in 2018.

A centipede bite is an injury resulting from the action of a centipede's forcipules, pincer-like appendages that pierce the skin and inject venom into the wound. Such a wound is not technically a bite, as the forcipules are modified first pair of legs rather than true mouthparts. Clinically, the wound is viewed as a cutaneous condition characterized by paired hemorrhagic marks that form a chevron shape caused by the large paired forcipules of the centipede.

The centipede's venom causes pain and swelling in the area of the bite, and may cause other reactions throughout the body. The majority of bites are not life-threatening to humans and present the greatest risk to children and those who develop allergic reactions.

Degloving and avulsion injuries involve the removal of the penis skin, which is a serious medical emergency. Treatment of these injuries involves either closure of the torn skin, or a skin graft to replace the skin lost in the injury. Skin grafts are constructed to attempt to preserve erectile function and sensation.

Depending on the duration of exposure aerosol-induced frostbite can vary in depth. Most injuries of this type only affect the epidermis, the outermost layer of skin. However, if contact with the aerosol is prolonged the skin will freeze further and deeper layers of tissue will be affected, causing a more serious burn that reaches the dermis, destroys nerves, and increases the risk of infection and scarring . When the skin thaws, pain and severe discomfort can occur in the affected area. There may be a smell of aerosol products such as deodorant around the affected area, the injury may itch or be painful, the skin may freeze and become hardened, blisters may form on the area, and the flesh can become red and swollen.

Penile fractures are the result of rupture of the tunica albuginea. They are fairly rare and can co-occur with partial or complete urethral rupture, though this is rare. Urethral damage occurs in 10–38% of cases. Fractures are treated with emergency surgery, and can be diagnosed with ultrasound, especially in pediatric cases. Penile fractures are caused by trauma to the erect penis, typically by suddenly bending it laterally during penetrative intercourse with the receptive partner on top of the penetrating partner, or during masturbation. They can be diagnosed by the "eggplant sign" and are characterized by a loud popping sound at the time of the injury, the result of the tunica albuginea rupturing. Other symptoms include severe pain, loss of erection, and swelling. Symptoms of urethral injury include hematuria, blood at the meatus, and dysuria. If left untreated, complications result in 28–53% of cases; these include permanent curvature of the penis, fistula, urethral diverticulum, priapism, and erectile dysfunction.

A pancreatic injury is some form of trauma sustained by the pancreas. The injury can be sustained through either blunt forces, such as a motor vehicle accident, or penetrative forces, such as that of a gunshot wound. The pancreas is one of the least commonly injured organs in abdominal trauma.

Pilon fractures are categorized by the Ruedi-Allgower classification system.