Concussion classification
Introduction[edit | edit source]
Concussions, otherwise known as mild traumatic brain injuries (TBI), have several methods of classification, breaking them down into either subtypes or classification by severity.
Subtype classification[edit | edit source]
A 2019 systematic review suggested the classification of 5 concussion subtypes: cognitive, ocular-motor, headache/migraine, vestibular, and anxiety/mood, the first 2 being the most prevalent[1]. This would allow for more specific treatments delivered according to one’s subtype. It is important to note that subtypes are fluid and can shift between each other. A 2020 systematic review supported the subtype classification system, finding existence of symptom clusters relating to migraine, cognitive, and emotional symptom clusters[2]. The review further found associations between symptom clusters - cognitive symptoms clustered with emotional symptoms (i.e. cognitive–emotional symptom cluster), sleep symptoms with emotional symptoms (i.e. sleep–emotional symptom cluster), and ocular symptoms with vestibular and cervical symptoms (i.e. neurological symptom cluster)[2].
Cognitive-emotional[edit | edit source]
Symptoms included: difficulty concentrating or remembering , brain fog, feeling more emotional or slowed down, irritability or sadness or nervousness[2]
Clinical significance: Associated cognitive and balance deficits, prolonged symptom duration and recovery, more severe symptoms and complex recovery[2]
Migraine[edit | edit source]
Symptoms included: headache, light or noise sensitivity, nausea[2]
Clinical significance: prolonged symptom duration and recovery, more severe symptoms, impaired visual and verbal memory, slower reaction time, balance deficits[2]
Sleep-emotional[edit | edit source]
Symptoms included: trouble falling asleep, sleeping more or sleeping less, feeling more emotional or irritable or sad, nervousness[2]
Clinical significance: prolonged symptom duration and recovery, more severe symptoms, lower sleep quantity, memory impairment, balance deficits[2]
Neurological[edit | edit source]
Symptoms included: double vision or blurred vision or other visual problems, vomiting, neck pain, pressure in head[2]
Clinical significance: more symptoms during smooth pursuit, horizontal & vertical saccades, vertical saccades, horizontal and vertical VOR, VMS, and NPC[2]
Severity classification[edit | edit source]
TBIs have traditionally been classified based on clinical severity scores; most commonly being the Glasgow Coma Scale (GCS). GCS: 13-15: mild injury, 9-12: moderate injury, and 8 or less severe injury[3]. A lower GCS, abnormal brain imaging findings, unconsciousness lasting > 30 minutes, or amnesia > 24 hours indicates a more severe form of TBI[4].
Concussion classification systems have been suggested before - the CSG consensus statement and the AAN Revised Position Statement on Concussion in Sport used to use a numerical grading scale to grade the severity of concussion[3]. However, these are no longer used for 2 reasons - because evidence indicates that a brief loss of consciousness in association with concussion does not predict clinical course of long-term cognitive impairment, and second, because the lack of loss of consciousness with concussion should not be used to justify more rapid return to play[5][6].
Instead, it has been proposed to adopt more individualised approaches to concussion management[3].
References[edit | edit source]
- ↑ Langdon S, Königs M, Adang EAMC, Goedhart E, Oosterlaan J. Subtypes of Sport-Related Concussion: a Systematic Review and Meta-cluster Analysis. Sports Med. 2020 Oct;50(10):1829-1842. doi: 10.1007/s40279-020-01321-9. PMID: 32720230; PMCID: PMC7497426.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 Langdon S, Königs M, Adang EAMC, Goedhart E, Oosterlaan J. Subtypes of Sport-Related Concussion: a Systematic Review and Meta-cluster Analysis. Sports Med. 2020 Oct;50(10):1829-1842. doi: 10.1007/s40279-020-01321-9. PMID: 32720230; PMCID: PMC7497426.
- ↑ 3.0 3.1 3.2 Kazl C, Torres A. Definition, Classification, and Epidemiology of Concussion. Seminars in pediatric neurology. 2019;30:9–13.
- ↑ LaFleur N. Concussion Care Manual: A Practical Guide.
- ↑ McCrory P, Meeuwisse W, Dvorak J, Aubry M, Bailes J, Broglio S, Cantu RC, Cassidy D, Echemendia RJ, Castellani RJ, Davis GA. Consensus statement on concussion in sport—the 5th international conference on concussion in sport held in Berlin, October 2016. British journal of sports medicine. 2017 Jun 1;51(11):838-47.
- ↑ Giza CC, Kutcher JS, Ashwal S, Barth J, Getchius TS, Gioia GA, Gronseth GS, Guskiewicz K, Mandel S, Manley G, McKeag DB. Summary of evidence-based guideline update: evaluation and management of concussion in sports: report of the Guideline Development Subcommittee of the American Academy of Neurology. Neurology. 2013 Jun 11;80(24):2250-7.
