It should come as no surprise to anyone in sports medicine that the understanding of mild traumatic brain injury (hence forth referred to as MTBI) is exponentially greater today than even 12 months ago. What is surprising is how long it took to get the attention of those of us in the field caring for individuals with sport-related MTBI. Surely, you would think that chronic and repeated head trauma to high profile athletes, be they boxers, football players, or hockey participants, should have peaked our interest. Yet, it has taken a relatively long period of time for many clinicians to make sense out of the often confounding variables and recommendations that surround both diagnosis and management of sport-related concussion and MTBI. What initially amounted to a simple extrapolation from the experience of caring for individuals with traumatic brain injury secondary to motor vehicle accidents and emergency room trauma has now blossomed into a full-scale rigorous research endeavor and a recognition of the subtleties of sport-related head trauma. A variety of tools (neuropsychological testing, postural stability testing, etc.) as well as the refinement of traditional neurologic orientation testing has enabled us to better describe with some degree of accuracy the “all too subtle” natural history of MTBI for the concussed athlete. This, in turn, has allowed clinicians the opportunity to question their personal return-to-play protocols originally based on experience, anecdotes, and published guidelines “de jour” to integrating new evidence into the care of concussed athletes. To be sure, we have yet to discover the elusive “One True Return-to-Play Guideline,” but the MTBI paradigm is definitely changing.
This special issue of the Clinical Journal of Sport Medicine features 10 articles on sports-related concussive head injury or MTBI in athletes. Grindel and colleagues provide a comprehensive and thorough review of our current understanding of neuropsychological (NP) testing as well as its potential use in the management of MTBI. While we must be careful of how we use any new tool, it is becoming more apparent that NP testing will play a significant role in how we think about and manage concussions in the future. Dr. Michael McCrea provides an overview of the current thinking on the potential use of a standardized mental status sideline evaluation. Postural stability assessment provides additional information that appears sensitive enough to detect “hard” neurologic signs and impairment up to 3 days postinjury. The “puzzle” as Dr. Guskiewicz describes it still doesn't fit together, however, and we are now aware that some concussions result in predominantly vestibular and postural symptoms that may not be detected with traditional on-the-sideline evaluations. Although symptom severity, neurocognitive function, and postural stability can be affected initially following concussion, they are not necessarily related or even affected to the same degree. Recent technologic advances invite the possibility that diagnostic imaging will play a greater role in the evaluation of concussions. Karen Johnston and colleagues outline some of the recent developments in functional brain imaging that may be useful in identifying underlying pathology following concussion. Perhaps the most important task ahead of us is the development of guidelines that aid management of MTBI and concussion in athletes through evidence-based medicine. McCrory, Johnson, and colleagues bring us up to date from both the basic science and clinical science standpoint with two evidence-based reviews. Dr. McCrory also discusses the existence of second impact syndrome and calls into question those current guidelines based on second impact syndrome dictating the management of concussion. In yet another article, McCrory reviews some of the newer pharmacologic treatments being proposed for MTBI. It would appear from his discussion that no evidence-based pharmacologic treatment exists at the current time to offer the concussed athlete. Another important question facing clinicians in the counseling of athletes and families of athletes is the risk for long-term neurological consequences from repeated MTBI. We still don't know how many concussions should result in termination of an athlete's career. Meheroz Rabadi and Barry Jordan review the current literature and conjectures, based on their experience with professional boxers and soccer players, to shed some light on this important public health concern and the risks for chronic traumatic brain injury with repeated MTBI. Finally, Professor Mitten brings the reader up-to-date with current legal standards summarizing nicely the recent cases and judgments that have come down concerning MTBI.
Please understand that the road to universal agreement of return-to-play guidelines following sports-related MTBI is long and arduous. These papers do not represent a uniform recommendation, but rather an explanation and review of where we are currently, and perhaps more importantly, what we don't know about sports-related concussion and MTBI. Uniformity in diagnosis and treatment continues to elude us. There is no gold standard test for diagnosis of MTBI, which makes our newer diagnostic tests somewhat difficult to interpret at this point in time. It is not the intent of this special issue to espouse any existing or yet-to-be-defined set of rules for MTBI management. We simply are not there yet. Rather, it is hoped that the reader will be enlightened by the evidence-based work presented here and the potential for new diagnostic tests and procedures.
For decades, team physicians have done an excellent job applying their own personal paradigms to the management of head-injured athletes. As you read these articles, it may occur to many of you that what was at one time intuitive is now becoming evidence-and outcome-based. Still others may have more questions than answers. We are indebted to both the authors and reviewers of the manuscripts in this special issue who have devoted their time and critical honesty to bring to the forefront our current thoughts on diagnosis and management of MTBI and concussion in athletes. Remember, as physicians caring for injured athletes, we must apply what we know to each situation on a case-by-case basis when arriving at the best possible care of the head-injured athlete. Grade school children should benefit from our new understandings just as much as high profile professional athletes. Perhaps, we will come to the revelation that there will never be “One True Return-to-Play Guideline.” Perhaps, we will come to realize that MTBI should be described, not categorized, then treated and managed based on the entire clinical picture. The simple axiom that no two concussions are alike is becoming more apparent as we learn more. Indeed, a change is definitely in the air.
We welcome your comments as you read this special thematics issue of the Journal.