MATERIAL and METHODS: Studies were searched in various electronic databases (MEDLINE/PubMed, EMBASE, CINAHL, Scopus and Cochrane databases) from their commencement to May 2021. Studies were included if athletes aged 12 years and older were diagnosed with a concussion injury and evaluated using serum biomarkers. Studies including athletes with injuries other than concussion injuries were excluded. Articles with fewer than 20 concussed athletes were excluded. There were 1782 articles identified.

RESULTS: After exclusion a total of 17 articles qualified for systematic review. S100 calcium binding protein ? (S-100?) and ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) showed promising results in distinguishing concussed athletes from contact sports and non-athlete controls. Most of the serum biomarkers increased within 6 hours of SRC. Serum neurofilament light protein (NFL) positively correlated with the severity of post-concussion symptoms. NFL, tau and Interleukins (IL-1 Ra and IL-6) have the potential to determine return to play.

CONCLUSION: Serum biomarker measurement is an objective tool that aids in early diagnosis and predicts the severity and prognosis of injury. Keywords : Serum biomarkers, Sports-related concussion injury, Mild traumatic brain injury, Concussed athletes, Return to play