Sports Medicine Research: In the Lab & In the Field: DWC- Driving While Concussed (Sports Med Res)


Monday, March 13, 2017

DWC- Driving While Concussed

Driving after Concussion: Is it Safe To Drive after Symptoms Resolve?

Schmidt JD, Hoffman NL, Ranchet M, Miller LS, Tomporowski PD, Akinwuntan AE, Devos H. Neurotruama. 2017; 34:1-8.
Take Home Message: Asymptomatic concussed patients exhibited poor vehicle control, which suggests that driving impairments persists after signs and symptoms resolve.

Concussion consensus statements address return to sport and return to school, but few address return to daily activities such as driving. Often patients are unaware that deficits, such as those with reaction time and executive function, persist even after concussive symptoms resolve. These impairments create an unsafe condition if a patient gets behind the wheel prior to full recovery. Unfortunately, there is little research examining when is it safe for a patient to drive after a concussion. Therefore, the authors compared the neuropsychological tests and driving performance using a desktop simulator between 14 participants with a concussion (~48 hours following symptoms resolution) and 14 matched (age, sex, years driving experience) healthy participants. The authors also explored the relationships between neuropsychological and driving performance. All participants were of driving age (~20 years old) and reported no more than 3 previous concussions. All participants completed a 20.5km driving simulation task involving daily-life traffic in urban, suburban, and rural areas and the authors calculated total number of crashes, tickets, and lane excursions. During the neuropsychological assessment participants completed the Trail Making Test, symbol digit modalities test, Rey Osterrieth Complex Figure, Mental Rotation Task, and CNS Vital Signs. Concussed participants committed more frequent lane excursions, and exhibited greater side-to-side deviation during the first and final curve compared with controls. There were no differences in the neuropsychological assessment between groups. Poorer performance on symbol digit modalities, Rey Osterrieth Complex Figure verbal memory, and motor speed were related with more frequent lane excursions in the concussed group, but not in the control group.

The authors of this study found that despite the participants reporting that they were asymptomatic the concussed participants exhibited poorer driving performance compared to their matched counterparts. Hence, impairments persisted beyond when the participant feels they are ready to fasten a seatbelt and drive. Specifically, the concussed participants had trouble staying centered in a lane. Though, the participants seemed to cross over to the shoulder instead of the center lane there is still an increased risk for vehicle accidents. Additionally, the authors reported that performing poorly on neuropsychological tests was related with poor driving performance. These results provide preliminary data that may guide future developments of a comprehensive driving evaluation following a concussion. This is an important study as it brings to light some of the activities of daily life that medical professionals often fail to specifically address in the return to play of an athlete. Return to driving needs to be considered since it is a complicated task, and we need to start addressing this in our concussion education and return to play plans.

Question for Discussion: Do you feel driving should be restricted following a concussion? If so, when should readiness to return to driving be determined?

Written by: Jane McDevitt, PhD
Reviewed by: Jeff Driban

Related Posts:
Inter-association Guidelines: Independent Medical Care for College Student-Athletes, Diagnosis and Management of Sport-Related Concussion, and Year-Round Football Practice Contact

Schmidt JD, Hoffman NL, Ranchet M, Miller LS, Tomporowski PD, Akinwuntan AE, & Devos H (2017). Driving after Concussion: Is It Safe To Drive after Symptoms Resolve? Journal of neurotrauma PMID: 27959745


Nicholas Erdman said...

This is a great article highlighting a difficult task for the health care provider following diagnosis of a concussion. Many high school and collegiate student-athletes, as well as non-athletes, rely on driving as their mode of transportation to and from school, work, and home. Restriction of driving may place an additional burden on the individual, if unfounded.

While driving is currently restricted already following a concussion, literature was scarce in providing evidence to support the restriction. The connection that this article makes from the status of self-reporting as asymptomatic to poor driving performance is crucial in the decision-making process while managing a patient with a concussion. Increased lane excursion and side-to-side deviation would indicate a lack of motor control and a more dangerous driving environment for everyone on the road.

This article supports touches on a topic of concern following a concussion, however, a cutoff timeline needs to be developed. How long should the driving restriction last? 1 week post-asymptomatic? 2 weeks post-asymptomatic? The literature should answer this question with future research supporting this article’s findings and determining an appropriate time for safe return to driving activity. Return to safe driving may not be time-dependent, but also based on the results of reliable and valid tests following a concussion.

Brooke Daniell said...

The concept of this article is interesting, and extremely important. Often times, I think that myself, as an athletic trainer, can subconsciously overlook the "whole person" effects of injuries. It is easy to neglect thinking about other aspects of life that an injury might affect, beyond their sport. This brings to light a serious issue. When a person gets behind the wheel of a vehicle, they put more than just their own life at risk. If there is a possibility that concussed individuals may not be able to drive when recovering from a concussion, maybe we should be changing our suggestions to patients/parents of our patients, and explaining the seriousness of this issue to them. The article mentions that even after asymptomatic, the participants still scored below the controls. If we think about it, this really is not surprising. This is becoming present in other concussion literature as well; revealing that symptom resolution may not necessarily mean that the individual is completely healed, or that normal physiology has been completely restored.

Jane McDevitt said...

Nicholas and Brooke both bring up salient points that this is an alarming part of everyday life that we may have been neglecting. What is more alarming is that we cannot just rely on s/s or length of s/s to determine safe return to driving. We obviously cannot all perform driving simulations to test whether or not athletes are ready to get behind the wheel. So, we need to discuss which tests we can conduct to ensure safe return to safe driving. The authors of the study found that though there were no differences between the neuropsych tests there were correlations in poor performance on symbol digit modalities, Rey Osterrieth Complex Figure verbal memory, and motor speed were related with more frequent lane excursions in the concussed group, but not in the control group. However, these are not commonly used concussion assessment tools so we may need to consider implementing these to determine driving readiness.

Aleah Kirsch said...

The concept of driving while concussed is a very interesting one to ponder. I can admit that driving is a task that I do not particularly address once an athlete is diagnosed with a concussion. I address driving to the athlete during the immediate care but other than that I don’t really give guidelines of when one can return to driving. It does make complete sense to control for this and also not allow one to drive while experiencing symptoms. Some describe the symptoms of concussion similar to intoxication and individuals are not able to drive while intoxicated, why would they be able to drive while concussed? I do think there should be restrictions placed upon driving while concussed and these should most likely align with resolution of symptoms and SCAT results. It was interesting to see that this study found deviations in ability to maintain proper lane positioning and reaction time. It is a complicated question to answer when it comes to how the readiness to drive should be addressed. Driving is cognitively a difficult task even though it most of the time comes effortlessly therefore it could be difficult to determine readiness to return to driving. I think for the safety of the concussed individual and others, this should be a reintegration that is not rushed.

Jane McDevitt said...


I agree this is a concerns that cannot be rushed. I think you bring up a good point about when to lift the driving restrictions. You stated the possibility after S/S and SCAT3 results. In this study, all of the patients were s/s free, but I think you are right, I would like to see how the typically concussion tests such as SCAT3 correlate with driving readiness.

Landon Lempke, ATC said...

I believe that this article highlights a very important aspect of activities of daily living that we sometimes neglect in the sports medicine setting. As already mentioned by Nick, Brooke and Aleah, this was a very insightful study and highlights some key points to consider when treating individuals who are recovering from a concussion. My reaction to this article was thinking about individuals who drive semi-trucks who have suffered a concussion. These large vehicles require more focus and precision to drive compared to an average vehicle while also having a capability of causing far more damage if involved in an accident.
This is definitely a foundational study and further research will need to be conducted in order to potentially determine when it is safe to return to driving.
Some additional thoughts this study provoked were:
- what other tasks of daily living do we allow concussed individuals to do that may be dangerous? Activities such as riding a bike on a street or performing household chores might be more hazardous than we think.
- If someone is impaired after driving even once asymptomatic, are they impaired performing occupational tasks as well? I think specifically of occupations such as construction workers, machinists, and other manual labor jobs where an increased change of injury is already present. Are we placing individuals at an increased risk for injury?
The need for future studies examining other activities of daily living are warranted and I believe this article is a strong primer for future research.
To answer the proposed question, yes I believe driving should be restricted following concussion. For how long after impact and until what point I do not have a strong answer. I believe if normative data can be determined that shows at a certain time point following concussion that individuals return to a normal driving level then we can better answer these questions.
My question for the author is: If normative data is found, how do you forsee that data playing a role in the management of return to driving, especially in cases where individuals may fall outside the normative timeline or have post-concussion syndrome? Do you think it is reasonable to have individuals to undergo a driving assessment to ensure they are safe to return to driving?

Jane McDevitt said...

You bring up some really great points. The average age of the participants was 20 years old, and 2 of them did hold a Class B commercial driver's license (one concussion and one control). The concussed participants were not just recruited from athletics so some of the participants suffering with concussions may hold a manual labor based job (construction, contracting, bus driving). And, as you said, we should be looking at and considering other activities of daily life that may involve more cognitive and neuromuscular control (stair climbing, cooking, reaching on your toes to grab an object).

To answer the posted question I can really only post my opinion. Because I do not foresee everyone obtaining a driving simulator for their concussion assessment protocol I think we will probably have to rely on some sort of normative data set out from an array of cognitive/neuromsuscular control/reaction time based assessments. I think education will still be the key and ensure the patient understand the risk they pose to themselves and other when they get behind the wheel while they are still in the healing process. As far as having concussed patients undergo a driving assessment I am not sure that is feasible. There would need to be a lot more questions answer such as who would conduct these driving tests? Nobody likes to visit the DMV, and do medical professionals have the time to do the clinical eval and driving test. What skills would the test need to cover? What would the score card look like? Because driving is state regulated would we need to get that type of regulation passed by the state?

This certainly opens the door to a broad list of discussion points.

Tyler Keith said...

Driving post concussion is always something I'm asked about by my athletes, and always a question I've struggled with. Although I've never read any definitive evidence suggesting if an athlete should not be able to drive post concussion, and if so for how long, I've always used caution and recommend the athlete not drive until asymptomatic. This article provides reason for my guideline, although I do not believe it is an adequate assessment of a person's ability to drive following a concussion. Even with the most accurate driving simulator, it is still not completely the same as driving in real life. Also, following concussion, athletes tend to have sensitivity to screens such as a TV, phone, or computer, and it could be possible that the screen reignites some symptomology, explaining the worsened performance.

Either way, this article asks important questions going forward. I think going forward it will continue to be difficult to assess an individual's driving ability post concussion, due to the randomness that can occur with day to day driving. This cements my idea though that an athlete should remain away from the driver's seat until they are cleared to return to play. As athletic trainers, if we clear an athlete for full participation to play sports with all of the inherent risks, shouldn't that mean the athlete is cleared for all activities of daily living, including driving?

Jeffrey Driban said...

Tyler: Great point about an athlete's sensitivity to screens. I wonder though if that would also translate to a sensitivity to traffic lights at night. Hence, their sensitivity to screens could be an issue in this case.
I think you raise a good question about being cleared to sport vs cleared for activities of daily living. My sense is that not all activities of daily living should be treated the same and perhaps things like driving may need to be delayed - but that's just my opinion.

Catherine Hess said...

The title of this post caught my attention immediately. I sustained a concussion my senior year in high school and never once was anything mentioned about restricting my ability to drive. The very day that I sustained the concussion, I drove home almost in a time warp – not remembering how I got home. All other restrictions were strictly laid out on the forms provided – time at school, class work, splitting tests in to sections, phone and computer and television use, among other things – but driving was never mentioned. Looking back at it, it would have made sense to be restricted from driving and I have always wondered why that was not done. This article touches on a really important need for research around the concept of concussions because driving following a concussion is often times unaddressed. It makes complete sense that concussed drivers would show more errors when driving due to the deficits associated with concussions. The really important part of this study was that despite being asymptomatic, these errors still occurred with the concussed drivers. A time frame needs to be established that goes beyond symptom resolution for a safe return to driving, however the challenge comes with just how individualized each concussion is.
I do think that driving should be restricted following concussion – however, who would monitor this or assist with determining when they are cleared to return to driving? If someone is impaired on the road, it is not only their life at risk, but also the lives of others. The concept is one that must be thought out because ultimately this is something that should be part of concussion protocols. Neurocognitive tests could be the key to determining when reaction and processing speeds return to normal and the person could return to driving. This article is a huge step in the right direction because it brings light to certain activities of daily living that are impacted and overlooked. The only complication I see with this is whether this would be the responsibility of a sports medicine staff member because it seems to be outside of the realm of us assisting to return an athlete to play. We outsource for assistance with academic accommodations following a concussion, so would there be somewhere to outsource for this issue as well?

Jane McDevitt said...

Thank you for sharing your story. I agree driving restrictions following a concussion and determining other ADLs that may be overlooked is necessary for future research. However, I think you point out a major problem who has both the medical and driving knowledge to oversee this aspect of concussion care?

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