The objective of the study is to confirm the clinical relevance of the novel biomarker for traumatic brain injury (TBI) detection. Samples of blood, urine and saliva will be collected from a) patients with suspected TBI (isolated), b) patients with orthopedic injury, and c) healthy controls. The sponsor will do biochemical investigations for the samples to evaluate the presence, level and structure of the targeted biomarker.

The study will analyze and compare the levels of certain biomolecules and cellular degradation products which are released upon a brain injury and which become detectable in the body fluids. Patients with a traumatic brain injury are supposed to express these biomarkers in their body fluids while orthopedic trauma patients and healthy controls are supposed to be undetectable with respect to these biomolecules. The study is a case-control study where the study subjects with a property (injured) are compared to subjects without the property (healthy). The brain injury patient group will consist of subjects who entered the Emergency Department of the hospital with a suspected TBI. The orthopedic patient group will consists of patients who were admitted with a bone fracture in the limbs, but without a suspected TBI. The control group will consist of healthy subjects who will be recruited to the study by the activities of the study personnel.

The entire study is split into two successive parts. In the first Part I, 18 - 24 subjects will be recruited in each group. In the second part, the number of the patients with suspected TBI will be added to up to 100 in order to receive an adequate number of samples and to gain sufficient statistical significance between the brain injury severities and in successive sampling time points.

The collected samples and relevant clinical data of each subject will be supplied to the sponsor who will perform to the samples 1) Biochemical analysis for the presence and level of the biomarker, and 2) Biomarker profiling and structure analysis by LC/MS.

Inclusion Criteria:

• Signed written informed consent form (Finnish or Swedish)
• Age 18 - 75 years (Male or Female)
• For patients with a suspected TBI: Presenting to the ED within 4 hours after the injury, and no orthopedic trauma (fractures of long bones) present.
• For patients with a suspected TBI: Deemed to have a computed tomography (CT) scan as a part of their intended medical diagnosis and treatment.
• For patients with orthopedic injuries: Presentation with a bone fracture, but without any suspicion of any TBI.

Exclusion Criteria:

• Unknown time of trauma (uncertainty more than 1 hour).
• More than 4 hours from the injury.
• Known or suspected pre-existing neurological condition that can cause the observed symptoms
• For women of child-bearing age: known to be or suspected to be pregnant.
• History of seizures within the last three months.
• History of infection with HIV or hepatitis B, or diagnosed to be positive in the concomitant screening.
• Patients where the presence of TBI cannot be assessed reliably because of alcohol or drugs, especially current use of anti-psychotic or anxiolytic medication.
• History of stroke within three months.
• The subject has a chronic neurodegenerative, metabolic (e.g. diabetes), or an autoimmune disease.

Data will not be shared with other researchers.

Analytical evaluation and testing laboratories will get the samples blinded (coded).