updates to the amsterdam concussion consensus statement

concussion consensus statement updates

case presentation

A healthy, 16-year-old female presents to your office with a 6 week history of persistent dizziness, mental fogginess and difficulty with concentration.  Upon further history, her symptoms seemed to begin after an incident in her woodshop class after being struck by a wooden board during an accident.  She thought her symptoms would improve on their own, but many symptoms have lingered.  Which of the following is the most accepted time frame for persistent post concussive symptoms? 

A. 10 days
B. more than 4 weeks
C. more than 8 weeks
D. more than 3 months

introduction

The newest consensus concussion statement dated October 2022 was recently released and should be reviewed by any sports medicine providers.  The first consensus meeting was in 2001(made available in 2002) and there have been six in total at this point.  The goal of this week’s post is to highlight the newest changes released in comparison to the fifth statement.

The goals of the most current statement are “updating current recommendations for sport-related concussion (SRC) through an evidence-informed consensus methodology.” It is also “to provide a summary of the evidence and practice recommendations based on science and expert panel consensus recommendations at the time of the conference [1].”

The definition has been evolving since the first consensus meeting.  The conceptual definition, accepted as a majority decision (78.6%) but not reaching an 80% consensus, is:

“Sport-related concussion is a traumatic brain injury caused by a direct blow to the head, neck or body resulting in an impulsive force being transmitted to the brain that occurs in sports and exercise-related activities. This initiates a neurotransmitter and metabolic cascade, with possible axonal injury, blood flow change and inflammation affecting the brain. Symptoms and signs may present immediately, or evolve over minutes or hours, and commonly resolve within days, but may be prolonged.

No abnormality is seen on standard structural neuroimaging studies (computed tomography or magnetic resonance imaging T1- and T2-weighted images), but in the research setting, abnormalities may be present on functional, blood flow or metabolic imaging studies. Sport-related concussion results in a range of clinical symptoms and signs that may or may not involve loss of consciousness. The clinical symptoms and signs of concussion cannot be explained solely by (but may occur concomitantly with) drug, alcohol, or medication use, other injuries (such as cervical injuries, peripheral vestibular dysfunction) or other comorbidities (such as psychological factors or coexisting medical conditions).”

Efforts and evidence to reduce collisions during practices has been increasing.  Another recent post reported an increase in SRCs during the most recent NFL season. The policy disallowing body checking in child or adolescent ice hockey reduced the rate of concussion in games by 58%. Evidence supports that policies disallowing body checking in youth ice hockey prevent concussions, and these policies should be applied for all levels of children’s ice hockey and most levels of adolescent ice hockey [2].  

Policy and rules limiting the number and duration of contact practices, intensity of contact in practices and strategies restricting collision time in practices in American football across all age groups have led to an overall 64% reduction in practice-related concussions and to reduced head impact rates [2]. 

Another important update involves updated screening tests.  There are updated tests available with the Concussion recognition tool (CRT6), Sports Concussion Assessment Tool-6 (SCAT6) and Child SCAT6 tests.  Updated versions for in-office assessment called the SCOAT6 and child SCOAT6 are now available and are intentionally made to allow for continuity of care and to parallel the care after a sideline evaluation and possible removal.  These acute sport-related concussion (SRC) tools are best used in the first 72 hours (and up to 1 week) after injury.   It appears the efficacy reduces after 72 hours [1].

Image 1: Voting process for SCAT6 recommendations [21].

The Child SCAT6 should be used in patients aged 8–12 years. The final determinations of content included in the SCAT6 and Child SCAT6 were based on findings from the systematic review as well as expert panel discussions highlighting the importance of the scientific evidence while balancing pragmatic considerations for the development and utility of the tools.

Each proposed change, except for the Vestibular-Ocular Motor Screen (VOMS), had >80% agreement to include as either recommended or optional. As a result, the VOMS was not included in the SCAT6.  There was a table on the process used on what to include in the new SCAT6 (Figure 2).  Ceiling effects were apparent on the 5-word list learning and concentration subtests. The use of more challenging tests, including the 10-word list, was recommended.

Figure 2.  SCAT6 recommendations summary.  Adopted from [1].

Some updates were made to the sideline management.  Signs were more concise: actual or suspected loss of consciousness, seizure, tonic posturing, ataxia, poor balance, confusion, behavioral changes and amnesia. Players exhibiting these signs should not return to a match or training that day, unless evaluated acutely by an experienced HCP with a multimodal assessment who determines that the sign was not related to a concussion [1].

Figure 3.  Concussion prevention recommendations .  Adopted from [1].

The process of conducting a multimodal screen to evaluate a potential concussion was given an estimated time of at least 10–15 min. Sport organizations are strongly advised to allow for at least that amount of time for an adequate evaluation and to accommodate such an assessment off-field, preferably in a quiet area away from the pressures and scrutiny of match play.

Figure 4.  Persistent symptoms recommendations. Adopted from [1].

Individuals can return to light-intensity physical activity, such as walking that does not more than mildly exacerbate symptoms, during the initial 24–48 hours following a concussion. This is a slight change from prior recommendations.  “HCPs with access to exercise testing can safely prescribe subsymptom threshold aerobic exercise treatment within 2–10 days after SRC, based on the individual’s heart rate threshold (HRt) that does not elicit more than mild symptom exacerbation during the exercise test,” which is more defined in this updated statement [3].

Figure 5.  SCOAT6 or office SCAT6 recommendations.  Adopted from [1].

Another addition and specification was a timeframe and recommendation specifically for specialized rehabilitation, which many physical therapists are being trained in and becoming more comfortable.  “If dizziness, neck pain and/or headaches persist for more than 10 days, cervicovestibular rehabilitation is recommended. If symptoms persist beyond 4 weeks in children and adolescents, active rehabilitation and collaborative care may be of benefit. For children, adolescents and adults with dizziness/balance problems, either vestibular rehabilitation or cervicovestibular rehabilitation may be of benefit [1].”

Another great addition to the statement is a specific mention of a return to learn (RTL) and more definite statements in regards to this.  One systematic review revealed that the vast majority of athletes (93%) of all ages have a full RTL with no additional academic support by 10 days [4]. The RTL process can be more challenging for those who have specific considerations (eg, high acute symptom severity, a prior learning disability) that may affect recovery.  Early return to activities of daily living should be encouraged provided that symptoms are no more than mildly and briefly increased (ie, an increase of no more than 2 points on a 0–10 point scale for less than an hour) [1].

There will likely need to be some communication between the HCPs and the academic supports of the school or schools.  The recovery in the classroom may be less structured than the return to sports protocols.

Figure 6: Return to learn table and recommendations.  Adopted from [1].

In recent years, CTE has been described as a neuropathological entity [5-6].To avoid conceptual confusion between the pathology and a possible clinical condition, the postmortem neuropathology is referred to as CTE neuropathologic change (CTE-NC). The literature suggests that CTE-NC is very uncommon in community samples and brain banks, using strict criteria for case identification, and more common in brain bank samples of former professional athletes with high exposure to repetitive head impacts.”

Changes in the descriptions of possible long term signs of repetitive head impacts and possible symptoms are occurring.  CTE-NC is a post mortem diagnosis like Alzheimer’s disease and not a clinical diagnosis. The first consensus criteria for traumatic encephalopathy syndrome (TES), a new clinical diagnosis, were published in 2021 [7].  These diagnostic criteria can be used to determine the extent to which CTE-NC identified after death was associated with this new clinical diagnosis during life.

Figure 7.  Updated recommendations for return to sport.  Adopted from [1].

There is a concussion in para sport group that helps guide management of concussion in para athletes.  Para athletes may experience a concussion in widely played sports like ice hockey and soccer, as well as in para athlete-specific sports such as wheelchair racing and para swimming.  Commonly used SRC tools (eg, SCAT) are not validated in the para athlete population and require a more individualized approach [8].

Summary

In conclusion, the summary and recommendations have encapsulated the most recent updates over the past five years.  We feel it did a great job in adding important tools are healthcare providers and the new screening tools should start to be implemented and providers should start becoming familiar with them.  It is clear that concussions require a team-based approach to safely return the athlete or patient to sports and learning, particularly if there are persistent symptoms beyond 4 weeks.  The evidence is changing constantly and there remains strong concern from the public in regards to potential long term deficits related to repetitive head impacts.

CASE CONCLUSION

The concussion consensus statement in Berlin tried to establish a time frame of greater than 14 days in adults and greater than 4 weeks in children, did not use the term “post-concussion syndrome,” but used the terminology “persistent post-concussive symptoms.”  Most recently, persistent symptoms with a recommendation of referral were those lasting more than 4 weeks.  The AMSSM position statement has aligned with the Berlin consensus statement and tried to define “persistent post-concussive symptoms,” or PPCS, with a time frame of >14 days in adults and >4 weeks in children . The statement has also made clear that persistent symptoms do not necessarily indicate there is ongoing injury to the brain and states it is critical to consider comorbidities and how they may affect recovery.

References

  1. Patricios JS, Schneider KJ, Dvorak J, Ahmed OH, Blauwet C, Cantu RC, Davis GA, Echemendia RJ, Makdissi M, McNamee M, Broglio S, Emery CA, Feddermann-Demont N, Fuller GW, Giza CC, Guskiewicz KM, Hainline B, Iverson GL, Kutcher JS, Leddy JJ, Maddocks D, Manley G, McCrea M, Purcell LK, Putukian M, Sato H, Tuominen MP, Turner M, Yeates KO, Herring SA, Meeuwisse W. Consensus statement on concussion in sport: the 6th International Conference on Concussion in Sport-Amsterdam, October 2022. Br J Sports Med. 2023 Jun;57(11):695-711. doi: 10.1136/bjsports-2023-106898. PMID: 37316210.
  2. Eliason P , Galarneau J-M , Kolstad AT , et al. Prevention strategies and Modifiable risk factors for sport-related Concussions and head impacts: a systematic review and meta-analysis. Br J Sports Med 2023:bjsports-2022-106656.
  3. Leddy JJ , Master CL , Mannix R , et al. Early targeted heart rate aerobic exercise versus placebo stretching for sport-related concussion in adolescents: a randomised controlled trial. Lancet Child Adolesc Health 2021;5:792–9
  4. Putukian M , Purcell L , Schneider K , et al. Clinical recovery from concussion: return to school and sport: a systematic review and meta-analysis. Br J Sports Med 2023
  5. the TBI/CTE group, McKee AC , Cairns NJ , et al. The first NINDS/NIBIB consensus meeting to define neuropathological criteria for the diagnosis of chronic traumatic encephalopathy. Acta Neuropathol 2016;131:75–86
  6. McKee AC , Stern RA , Nowinski CJ , et al.  The spectrum of disease in chronic traumatic encephalopathy. Brain 2013;136:43–64
  7. Katz DI , Bernick C , Dodick DW , et al. National Institute of neurological disorders and stroke consensus diagnostic criteria for traumatic encephalopathy syndrome. Neurology 2021;96:848–63. 

Derman W , Badenhorst M , Blauwet C , et al.  Para sport translation of the IOC consensus on recording and reporting of data for injury and illness in sport. Br J Sports Med 2021;55:1068–76