Concussive convulsions: A YouTube video analysis

Abstract

SUMMARYObjective: To analyze seizure-like motor phenomena immediately occurring after concussion (concussive convulsions). Methods: Twenty-five videos of concussive convulsions were obtained from YouTube as a result of numerous sports-related search terms. The videos were analyzed by four independent observers, documenting observations of the casualty, the head injury, motor symptoms of the concussive convulsions, the postictal period, and the outcome. Results: Immediate responses included the fencing response, bear hug position, and bilateral leg extension. Fencing response was the most common. The side of the hit (p = 0.039) and the head turning (p = 0.0002) was ipsilateral to the extended arm. There was a tendency that if the blow had only a vertical component, the bear hug position appeared more frequently (p = 0.12). The motor symptom that appeared with latency of 6 AE 3 s was clonus, sometimes superimposed with tonic motor phenomena. Clonus was focal, focally evolving bilateral or bilateral, with a duration of 27 AE 19 s (5-72 s). Where lateralization of clonus could be determined, the side of clonus and the side of hit were contralateral (p = 0.039). Significance: Concussive convulsions consist of two phases. The short-latency first phase encompasses motor phenomena resembling neonatal reflexes and may be of brainstem origin. The long-latency second phase consists of clonus. We hypothesize that the motor symptoms of the long-latency phase are attributed to cortical structures; however, they are probably not epileptic in origin but rather a result of a transient cortical neuronal disturbance induced by mechanical forces.

The pentagram of concussion: an observational analysis that describes five overt indicators of head trauma

“…and McCrory et al . have independently observed the Fencing Response in 16 and 25 cases respectively [ 10 , 11 ]. In our initial characterization, we provide histopathological evidence that the Fencing Response coincides with non-focal BBB disruption and neuronal injury in the LVN acutely after moderate, but not mild TBI in the rat [ 9 ].…”

“…Directionality of forces may correlate with laterality of the Fencing Response as Tényi el al. describes a significant relationship between the patient’s head turning towards the extended arm and directionality of forces [ 10 ]. The absence of this finding here and in our 2009 publication may be due to variations in aggregate force vectors of brain injury or limited sample populations.…”

Medical retirement from sport after concussions

“…Aside from LOC, various acute neurologic signs may be observed immediately following SRC, and deserve specific consideration in retirement discussions given their obvious and arguably worrisome features. These include (1) “immediate epilepsy” or “impact seizures,” which can manifest as generalized tonic-clonic seizures, 33 (2) “concussive convulsions” (including fencing and other tonic postures), 34 , 35 and (3) other signs suggesting disturbance in neurologic function due to sudden and substantial mechanical forces affecting cortical or subcortical structures. Mild TBI is associated with incident posttraumatic epilepsy but is uncommon even following LOC or impact seizures.…”

“… 36 Like seizures, concussive convulsions (case 6) are thought to have a benign prognosis, but data on long-term outcomes are limited to small case series. 34 , 35 Behavioral changes following SRC are well-recognized 37 and although rare, our group has also cared for patients with brief episodes of uncontrollable laughter and crying with preservation of consciousness immediately following SRC impact. It is uncertain if these specific events should be considered in a spectrum of adult nonhamartomatous gelastic or dacrystic seizures.…”

A review of seizures and epilepsy following traumatic brain injury

“…They are convulsive and occur within seconds of impact. Their semiology differs from tonic-clonic seizures and is postulated to contain elements of primitive reflexes [12]. They are believed to carry no risk of later epilepsy.…”