Sports Medicine Update: Concussion

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Key points

  • A concussion is a form of traumatic brain injury with both functional and structural disturbances, both of which occur at a level that precludes detection with standard imaging modalities available in the emergency department.

  • A systematic approach is necessary when assessing a patient in whom a concussion is suspected. Although standardized tools help in the assessment of patients with concussion, the diagnosis of concussion remains a clinical one.

  • Patients diagnosed with a concussion should be

Pathophysiology

The basic pathophysiology of concussion is still being investigated, and although much work has been done, there is no unifying theory. It is often simplistically stated that a concussion is the result of a functional abnormality and not a structural one, but it is more likely that it is both functional and structural. However, despite this, the structural changes are often not visible on standard imaging techniques such as computed tomography (CT) and magnetic resonance imagery (MRI).

A

Clinical features

The most commonly cited definition states that a concussion is a TBI induced by biomechanical forces.15 Common features that help to define concussions clinically include:

  • Concussions can be caused by a direct blow to the head, face, or neck, or elsewhere on the body with the impulsive force transmitted to the head.

  • Concussions typically result in a rapid onset of short-lived neurologic impairment that resolves spontaneously but may evolve over several minutes to hours.

  • The symptoms of concussion

Assessment

Head-injured patients should first be evaluated to rule out more severe injuries. The Canadian CT Head rules can help to reduce the number of unnecessary CTs performed while identifying disorder that requires intervention.16 In addition, the use of the Canadian C-spine Rule or National Emergency X-Radiography Utilization Study (NEXUS) criteria can help to identify patients who require cervical spine imaging.17 After a more serious disorder, such as an intracranial or spinal cord injury, is

Management

Recommendations regarding concussion management are often based on low-quality evidence and expert opinion. It is increasingly understood that patients’ recovery from concussion is highly variable, requiring individualized recommendations, and there will likely never be a one-size-fits-all management strategy. Although most patients benefit from an initial period of rest, others benefit from an early, more active rehabilitation strategy. Although recommendations as to best practice can be

Persistent Postconcussion Symptoms

Persistent postconcussion symptoms (PPCSs) refers to symptoms that persist beyond what would be considered the normal recovery period. There is debate as to when recovery is considered prolonged, ranging from 2 weeks to 3 months.15, 19, 38 Given the likely benefit of earlier identification and intervention for patients at risk of prolonged recovery, it is reasonable to consider a diagnosis of PPCS when symptoms persist for more than one month. The cause of prolonged symptoms is debated and

Prevention

Concussion prevention can be grouped into education initiatives, rule changes, and legislative changes, as well as the use of protective equipment.

Changing the rules in sports has been found to achieve the desired effect of reducing the incidence of head injuries. For example, eliminating body checking in youth hockey in Canada, or eliminating drills involving full-speed and head-on blocking or tackling as well as limiting full-contact practice time in high school and youth football, have

Summary

Patients commonly present to the ED with head injuries. A systematic approach is required for patients with suspected concussion, and although standardized tools can aid in assessment, the diagnosis of concussion remains a clinical one. At the time of diagnosis, patients should be given both a verbal and written review of the common symptoms of concussion as well as symptom-management strategies. Most patients benefit from a brief (24–48 hours) period of rest, followed by a gradual

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  • Cited by (10)

    • Pediatric and adolescent sports concussions

      2023, Encyclopedia of Child and Adolescent Health, First Edition
    • Mechanical threshold for concussion based on computation of axonal strain using a finite element rat brain model

      2021, Brain Multiphysics
      Citation Excerpt :

      Worldwide sixty-nine million people are estimated to suffer from a TBI each year [4], among which 80-90% belong to mild injury category [4,5]. Though mortality rate in the case of mTBI is below 1%, the long term consequences are serious and adversely affect the lives of individuals, their families and the wider society [5], especially when the occurrence is repeated as in the contact sports [6–8]. Since, diffuse axonal injury (DAI) due to sudden axonal stretch is known to be one of the most frequent pathological features of TBI [9–13], knowledge of the mechanical threshold for concussion in terms of axonal strain [14–17] can help in developing better brain injury prediction tools to be applied in optimizing head protection systems or in managing sport related concussions.

    View all citing articles on Scopus

    Disclosures: None.

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