What is an OSI?

An Operational Stress Injury (OSI) is a psychological condition resulting from duties during police or military operations. It can include conditions ranging from  depression, anxiety, post-traumatic stress disorder (PTSD), substance use issues or stress related medical issues. Operational stress is generated by single or multiple exposures to situations involving trauma to others or to oneself. These can lead to problems in personal, family or work functioning. 

Symptoms of Post Traumatic Stress Disorder and Depression

The recently revised DSM-5 sets out a number of areas of symptoms that need to be met for the diagnosis of PTSD to be provided. They are:

Intrusive Experiences

These include dreaming of the traumatic incident(s), daytime flashbacks of the incidents, and highly stressful responses to reminders of the incident, all of which can be quite distressing. These experiences can intrude on social, family, and occupational function.


Avoidance or a phobic response to the site of the incident(s) can develop.  For example, those injured in a vehicle might have a strong fear reaction to being in or around vehicles. As in any phobia, the fear can be amplified by avoidance of the stimuli. For example, the person who responds by  avoiding vehicles often experiences increased fear of driving.

Negative alterations in cognitions and mood

These include negative beliefs about oneself, others, or the world, related to the incident such as inapropriate self blame, or concluding that the world is unsafe. Negative mood states include emotional distance or detachment from those who are close to you, which can cause significant interpersonal and relationship issues, or lack of interest in things that used to motivate you. 


Arousal experiences include phenomena such as an exaggerated startle response to any stimuli that may or may not be related to the incident, including movement or sounds. Insomnia, irritability, and anger are also common. Arousal also can cause cognitive deficits such as problems with concentration/attention, short term memory, decision making, multitasking, and thinking speed. These symptoms can mimic ADHD or concussion, but are temporary. 


Depression can be present with or without PTSD. Depression can be caused by accumulated stress over time, compassion fatigue, losses such as the death of a colleague, or sustaining a physical injury. It can also be secondary to losses associated with PTSD such as decreased vocational, personal, and social functioning. Symptoms of depression can overlap with PTSD, but generally include sadness and tearfulness, loss of interest, low motivation, insomnia, excessive sleeping and may include cognitive problems.