The results of these two case studies highlight the effects of sports-related concussion in girls compared to pre-injury baseline functioning and suggest that neurocognitive changes are seen following even a single injury. Furthermore, these changes may persist following the resolution of post-concussion symptoms suggesting a need for thorough neuropsychological evaluation and follow-up in youths who have sustained a concussion or mTBI. For example, case study 1 experienced a resolution of symptoms by 5 days post-concussion, but still demonstrated significantly reduced visual motor reaction time at 11 days post-concussion. Case study 2’s data also illustrates that recovery does not necessarily follow a linear model, as she experienced fluctuation in performance on attention measures across testing sessions, where she initially demonstrated an absence of symptoms, followed by fluctuating improved and decreased performance. This variability in performance may have been the result of her activity level during the day of each testing session as too much activity following mTBI can result in a delayed onset of symptoms—one reason why a gradual return to activity is recommended postconcusssion.8
A resolution of symptoms is interpreted as a return to baseline levels. This does not necessarily reflect a complete absence of these symptoms. A rating of 4 or 5 during baseline testing may reflect endorsement of some of the symptoms, which can occur unrelated to a concussion. For example, perhaps the patient had a headache that day or was tired from a vigorous hockey practice. In addition, there may be individual differences in the extent to which people endorse and report such symptoms, which is why a baseline rating is obtained for each individual. Cut-offs for classification of concussion severity are as follows: 0–21/126 = absence of (or minimal) symptoms; 22–41 = mild; 42–84 = moderate and 105–126 = severe.11
The results of this case series provide support for previous research suggesting that attention may be particularly vulnerable to the effects of mTBI in youths,8
as both girls demonstrated difficulties with attention that did not resolve by mid-season testing 39 days later for case study 1 and 34 days later for case study 2. Case study 1 demonstrated significantly higher inattention at the mid-season testing session, while case study 2’s performance on the ANT revealed poorer executive function of attention. The results also highlight the variability of effects of mTBI on neurocognitive function. For example, case study 1 demonstrated difficulty with verbal memory, while case study 2 showed preserved verbal memory function but demonstrated significantly poorer visual memory ability post-injury. On the ANT, the pattern of results for alerting and orienting also varied according to the individual. While both case study 1 and case study 2 showed altered executive function post-concussion, the recovery was variable and may have been influenced by previous injury for case study 2 who still demonstrated poorer performance compared to pre-injury baseline function at the mid-season testing session. These findings further support the need for thorough neuropsychological examination following mTBI in youths in order to fully capture the effects of the injury on brain function.
We previously described a case study of a boy (14 years of age)12
who sustained two concussions within a 24 h period. The data from the current case studies is similar to those findings with elevated post-concussion and neurocognitive symptoms in the boy following injury and a protracted recovery curve, possibly related to the occurrence of multiple injuries and a premature return-to-activity prior to full symptom resolution. Similar to the boy, both girls in the current study exhibited variability in attention that did not return to pre-injury baseline functioning even at a mid=season baseline testing session.
Neither case study 1 nor case study 2 received any neuroimaging follow-up as a result of their concussion (ie, CT scan or MRI). As indicated in the recent Consensus Statement on Concussion in Sport,8
conventional structural neuroimaging is typically normal in concussive injury. As such, the consensus statements make the following suggestions: ‘Brain CT (or, where available, MR brain scan) contributes little to concussion evaluation but should be employed whenever suspicion of an intracerebral structural lesion exists. Examples of such situations may include prolonged disturbance of conscious state, focal neurological deficit or worsening symptoms’.8
These case studies represent an important first step towards examining recovery from mTBI in youth. There is little data available regarding recovery from mTBI specific to children and youths with an even greater gap pertaining to gender influences during this critical stage of development. The results suggest that children and youths require greater caution when returning to play following injury, especially if there has been more than one injury, and that thorough and ongoing neurocognitive assessments may be required in order to fully uncover the effects of injury as well as determine recovery, given that some neurocognitive effects are still observed once post-concussion symptoms have resolved even after a single injury.
- Results suggest that children and youths require greater caution when returning to play post-injury.
- Thorough and ongoing neurocognitive evaluation is required in order to fully illustrate the effects of the injury and determine recovery.
- Neurocognitive effects of the injury may be observed even once post-concussion symptoms have resolved.
- More large-scale research is needed to better understand recovery from mTBI in children and youths and to provide evidence-based guidelines for clinical management and return-to-activity.