Concussion in Professional Football: Comparison with Boxing Head Impacts—Part 10

Mild Traumatic Brain Injury Committee, National Football League, New York, New York, USA.
Neurosurgery (Impact Factor: 3.62). 01/2006; 57(6):1154-72; discussion 1154-72. DOI: 10.1227/01.NEU.0000187541.87937.D9
Source: PubMed


This study addresses impact biomechanics from boxing punches causing translational and rotational head acceleration. Olympic boxers threw four different punches at an instrumented Hybrid III dummy and responses were compared with laboratory-reconstructed NFL concussions.
Eleven Olympic boxers weighing 51 to 130 kg (112-285 lb) delivered 78 blows to the head of the Hybrid III dummy, including hooks, uppercuts and straight punches to the forehead and jaw. Instrumentation included translational and rotational head acceleration and neck loads in the dummy. Biaxial acceleration was measured in the boxer's hand to determine punch force. High-speed video recorded each blow. Hybrid III head responses and finite element (FE) brain modeling were compared to similarly determined responses from reconstructed NFL concussions.
The hook produced the highest change in hand velocity (11.0 +/- 3.4 m/s) and greatest punch force (4405 +/- 2318 N) with average neck load of 855 +/- 537 N. It caused head translational and rotational accelerations of 71.2 +/- 32.2 g and 9306 +/- 4485 r/s. These levels are consistent with those causing concussion in NFL impacts. However, the head injury criterion (HIC) for boxing punches was lower than for NFL concussions because of shorter duration acceleration. Boxers deliver punches with proportionately more rotational than translational acceleration than in football concussion. Boxing punches have a 65 mm effective radius from the head cg, which is almost double the 34 mm in football. A smaller radius in football prevents the helmets from sliding off each other in a tackle.
Olympic boxers deliver punches with high impact velocity but lower HIC and translational acceleration than in football impacts because of a lower effective punch mass. They cause proportionately more rotational acceleration than in football. Modeling shows that the greatest strain is in the midbrain late in the exposure, after the primary impact acceleration in boxing and football.

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Available from: Liying Zhang, Mar 12, 2015
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    • "There is therefore a critical need for research to elucidate the relationship between the neuropathological underpinnings of TBI and neurobehavioral outcome, particularly in our vulnerable combat-exposed Veterans who have been exposed to both blast and blunt force TBI. Although possible brainstem dysfunction has been at the forefront of the TBI literature for several decades, (Adams et al. 1977; Cernak et al. 2001; Foltz et al. 1953; Garman et al. 2011; Moruzzi and Magoun 1949; Plum and Posner 1980; Strich 1961; Verhaal and van 'T Hooft 1975; Viano et al. 2005; Ward 1958) few human studies exist, imaging studies have been very limited, and, to our knowledge , no study has examined associations between white matter integrity of the brainstem, injury severity, and PCS symptoms in the context of military TBI. Clearly, linkages of LOC and PCS symptoms—typically associated with vegetative signs of psychiatric origin—to a neuroanatomic substrate would have very important implications for this relatively new field. "
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    ABSTRACT: We investigated associations between DTI indices of three brainstem white matter tracts, traumatic brain injury (TBI) injury characteristics, and postconcussive symptomatology (PCS) in a well-characterized sample of veterans with history of mild to moderate TBI (mTBI). 58 military veterans (mTBI: n = 38, mean age = 33.2, mean time since injury = 90.9 months; military controls [MC]; n = 20; mean age = 29.4) were administered 3T DTI scans as well as a comprehensive neuropsychiatric evaluation including evaluation of TBI injury characteristics and PCS symptoms (e.g., negative mood, dizziness, balance and coordination difficulties). Tractography was employed by seeding ROIs along 3 brainstem white matter tracts (i.e., medial lemniscus-central tegmentum tract [ML-CTT]; corticospinal tracts [CST], and pontine tegmentum [PT]), and mean DTI values were derived from fractional anisotropic (FA) maps. Results showed that there were no significant difference in FA between the MC and TBI groups across the 3 regions of interest; however, among the TBI group, CST FA was significantly negatively associated with LOC duration. Additionally, lower FA of certain tracts-most especially the PT-was significantly associated with increased PCS symptoms (i.e., more severe vestibular symptoms, poorer physical functioning, and greater levels of fatigue), even after adjusting for PTSD symptoms. Our findings show that, in our sample of veterans with mTBI, tractography-based DTI indices of brainstem white matter tracts of interest are related to the presence and severity of PCS symptoms. Findings are promising as they show linkages between brainstem white matter integrity and injury severity (LOC), and they raise the possibility that the pontine tegmentum in particular may be a useful marker of PCS symptoms. Collectively, these data point to important neurobiological substrates of the chronic and complex constellation of symptoms following the 'signature injury' of our combat-exposed veterans.
    Brain Imaging and Behavior 08/2015; 9(3). DOI:10.1007/s11682-015-9432-2 · 4.60 Impact Factor
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    • "The reference impactor mass of 1.7 kg is in accordance with the previous work of Viano et al. [10], who used a mass of 1.67 kg. Fig. 1. 3D head model (sagittal section). "
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    ABSTRACT: Forensic investigations have been reported regarding the loss of consciousness and cardiac arrests resulting from direct mandible impact. However, the mechanisms by which the forces are transferred to the skull through direct mandible impact remain unclear. We conducted a study regarding direct mandible impact on the level of energy required to create a mandible fracture and on the energy dispersion phenomenon to the skull and to the brain. This study combines an experimental and numerical approach. Mandible strike was studied using experimental trials performed on post-mortem human subjects. A finite element model of the head and face of a male was also developed based on tomodensitometry scans. The model was validated with literature data and experimental trials. A parametric study was then performed to study the effect of diverse variables such as the dentition integrity, cortical bone thickness, etc. The forces measured on our reference model were 3000N on the chin, 1800N at the condyles, and 970N in the occiput. Of all the results, we observed a decrease of approximately one-third of the efforts from the chin to the base of the skull and a lower half of the still forces at the occiput, except in the edentulous and for the lateral and frontal impact where the force is transmitted directly to the skull base area. This study allowed us to create a 3D model of the mandible and face bones to better understand the force transfer mechanisms into and from the mandible. The parameters of the model may be modified to suit the individual characteristics for forensic investigations and legal matters. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
    Forensic science international 04/2015; 252. DOI:10.1016/j.forsciint.2015.04.017 · 2.14 Impact Factor
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    • "AND BOXING [14] METHODS BOXING TAEKWONDO (Viano et al. 2005) (Fife et al. "
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    ABSTRACT: The purpose was to examine differences between taekwondo kicks and boxing punches in resultant linear head acceleration (RLA), head injury criterion (HIC15), peak head velocity, and peak foot and fist velocities. Data from two existing publications on boxing punches and taekwondo kicks were compared. For taekwondo head impacts a Hybrid II Crash Dummy (Hybrid II) head was instrumented with a tri-axial accelerometer mounted inside the Hybrid II head. The Hybrid II was fixed to a height-adjustable frame and fitted with a protective taekwondo helmet. For boxing testing, a Hybrid III Crash Dummy head was instrumented with an array of tri-axial accelerometers mounted at the head centre of gravity. Differences in RLA between the roundhouse kick (130.11±51.67 g) and hook punch (71.23±32.19 g, d = 1.39) and in HIC15 (clench axe kick: 162.63±104.10; uppercut: 24.10±12.54, d = 2.29) were observed. Taekwondo kicks demonstrated significantly larger magnitudes than boxing punches for both RLA and HIC.
    Biology of Sport 12/2013; 30(4):263-8. DOI:10.5604/20831862.1077551 · 0.79 Impact Factor
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