DOCSLIB.ORG

Shock Absorbing Effectiveness of Hockey

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Shock Absorbing Effectiveness of Hockey MATERIALD SAN SCIENC SPORTN EI S Editedby: F.H. (Sam) Froes andS.J. Haake Dynamics Shock Absorbing Effectivenesf so Hockey Helmet Liner Foams After Exposure to Repeated Impacts SpyrouE. T.B.and Hoshizaki Pgs. 199-209 TIMS 184 Thorn Hill Road Warrendale 15086-751A P , 4 (724) 776-9000 SHOCK ABSORBING EFFECTIVENES HOCKEF SO Y HELMET LINER FOAMS AFTER EXPOSURE TO REPEATED IMPACTS E. Spyrou and T.B. Hoshizaki Sport Maska Inc. Department of Research and Development 600 Boul. Industriel St-Jean-sur-Richelieu, Quebec 4S7B J3 ,, Canada Abstract hockee ic e yTh helme consideres i t multiplda e impac nature game tth d th devic o f et an e o e edu the prolonged use of helmets by players. The liner foam is one of the many variables that influence impact absorption of a helmet. The purpose of this study was to investigate how inner liner foams, use hocken di y helmets, perfor mtermn i energf so y attenuation, following exposure repeateo t d impacts. Foam samples use thin di s experimen typesto wertw f :eo vinyl nitrile (VN) and expanded polypropylene (EPP) and measured 100 x 100 mm and were 12.5 mm thick. There were two phases to this experiment. In the first phase, which also served as the conditioning phase for the second, twenty impacts were performed repeatedly (1 minute between impacts) on thre level o e(C2J foamtw 0 f impacf energy1 e s)o o eacr th d sfo f d an ho t )an severitO (C J 5 y( liner type. In the second phase, a control set (Co) of foams (3 samples / liner type), not exposed to prior impact, along with the two sets of foams conditioned in phase I were tested once with an impact of 20 J. A monorail drop test was used to evaluate the foams. The type of liner foam and the severity of multiple impacts were both found to substantially affect liner impact absorption properties. Overal bese th l t performanc foamP observes EP e,e wa althoug th mors y db wa e N hV efficien absorbinn i t g impac t lowea t r energies. Such informatio e verb yn e nusefuca th n i l design of helmets and can possibly help prevent injuries. Materials and Science in Sports Edited by F.H. (Sam) Froes (ThS IM e Minerals, Metal Materials& s Society), 2001 200 Introduction With contact sport activities there exists a certain risk of injury - the game of ice hockey is no exception. The environment of play presents many chances for collision with the boards (e.g. wood, meta glass)& l , metal goal posts surfacee ic , , hockey sticks pucke th , , skate othed an s r equipment, as well as with the players of the opposing team. Consequently, ice hockey has a high rate of injury, frequently to the head and face (1,2,3,4,5,6,7). Priority, therefore, has been causee studgivee th th f heayf o no t s o d injurie meand san protectionf so hockee ic e yTh . helmet has improved protection to the head since its use became mandatory. The insurgence though of concussions recently promptes ha , d renewed attentio helmeo t n t designt no t quicA .bu k- necessaril bese y th solutio - t problee th o nt m woul tougheo t e d b performanc e nth e requirements set in certification standards. Certification standards have been a determinant factor of helmet performance and thus have influenced design to a great extent. It has been suggested that helmets be designed specifically for the unique conditions of each sport and all conceivable conditions shoul e consideredb taked dan n into accoun helmen i t t design r (8)feasibilitFo . y purposes, standard limitee sar scopen di , therefore overlooking importane somth f eo t conditions under whic game hth s playedei e sucOn h. conditio helmety nwa usee e woular sy th db e db players and how helmet performance is affected by the frequency and severity of blows that it is subjected to, during its lifespan. majoo Tw r type heaf so d protective devices exist firse Th .t type singla , e impact device uses i , d in very high energy impacts. Such impacts generally occu racn i r e car, motorcycle bicycld an , e accidents wher helmee eth t provides protection agains singla t e considere s i cras d han d unfio t t further protect the wearer following the crash. The second type, a multiple impact device, usually withstands impacts of less energy but is more durable. It is more effective in handling multiple impact situations. The ice hockey helmet falls under the second type of protective devices. This is due to the likelihood of less severe repetitive impact situations in the game of hockey. Initial research and development of ice hockey helmets was based on fundamental studies of human injury tolerance measures (9,10,11,12). In particular, linear acceleration levels have been shown to be a principal variable implicated in skull and cerebral injury. In general, the safety 2 threshol r headfo d impact s considerei s z (wheraroune 9.8= g b z 10 o g dt m/s1 de30 ), with minimal risk of skull fracture below 300 g; however, the relationship between linear acceleration and cerebral damage such as concussioz n in not well understood. As a result, the ultimate goal of helmets has been to reduce the energy transferred to the head. The extent of energy reductio s boti n a hfunctio e magnitudth f o n f deformatioo e e resultinth d an ng force proportiona lineae th o rt l deceleration achievo T . e this, helmets typically consis shela f o tl (outer covering) cushionina , g material (also calle liner)chinstrape a dth d an ,maio Tw n. type f foaso m deformation exist: plastic and elastic. The plastic material will not recover to its original shape following impact whereas elastic material will recover firse th t n casI . kinetie eth c energa f yo striking object is completely absorbed when the material has been fully compressed. Under a plastic deformation materiae th , l sustain deformatioa s n whic s beyonhi e elastidth c limid an t permanent damage is done. When the load is released, the material will not regain its original shap wilt distortee bu lb mechanica s it d dan l properties deformatiowile differene th lb o t e du tf no the materia moleculae th t la r seconlevele th n .I d case importane ,th t featur thas ei t while maximum force develope t affectedno s d i time th pea,o e t k forc doubleds ei . Unde elastin ra c deformatioe nth material can return to its original shape without any permanent damage. The bulk of material display both elastic and plastic properties to a certain degree. Depending on the use of the helmet, the material it is composed of, should possess more or less of the two material properties discussed (elasti . plastic)cvs r exampleFo . hocken i , y wher possibilite eth repeatea f yo d impact scenario 201 exists, material with more elastic properties woul suitable db e since recover materiae th f yo s i l crucial in dealing with subsequent impacts. Bishop indicates that these material consist of medium density resilient foams (13). Predicting impact absorption characteristics of helmets has proven to be difficult given the numerous material, geometric, and environmental factors and their interactions (14). The purpos f thio e so investigat t stud s wa y e effec th ef inne o t r liner typd environmentaan e l conditions (i.e. energy of impact and multiple impacts) on the impact attenuating characteristics of ice hockey helmets. To avoid confounding factors resulting from whole helmet testing, flat sectional samples representing typica hockee lic y helmet materials were evaluated (12,15). Methods Samples Liner samples were constructed possessing common construction characteristic f hockeo s y helmets presentl ymarkete use th squar m n di m sampl A .0 e line10 ex rconsiste 0 tha10 ta f do was 12.thick typem o 5m innef Tw .so r liner material were used: expanded polypropylene (EPP) an d5 kg/m 9 viny d 3an l a densitlinernitrilN 5 6 d V f ha sd eo y an (VN P ) EP foam e Th . respectively. Instrumentation Monorail System. The impact testing apparatus used was a monorail or guided-fall system (Figure 1), which consisted of a cylindrical metal guide supported from a beam anchored to a cement block at the lower end. This arrangement provided stability and uniform movement of the aluminum spherical impactor (calibration ball, diameter = 14.605 mm, mass = 4005 ± 5 grams) used to impact the samples (16). A carriage assembly supported the spherical impactor, universae th f o y lb ybalwa l joint combinee Th . d impacto e masth f so carriagd an r e assembly was 5.15 kg. Rotational movement of the spherical impactor was prohibited during impact. Given that this is the standardized impactor required for system calibrations, it was chosen to permi resulte th t thif so s studappliee industriab e o yth t n di l setting. An adjustable remote release mechanis uses m frecarriago wa e dt eth e assembly wit initiao hn l velocity. This release mechanis adjustee heighb y n an m achievt ca o t ta d desiree eth d impact energy level e surfacTh . e upon whic samplee hth s were positione r impacflaa dfo s t steewa t l anvil with a surface area of 0.09 m2.
Load more

Recommended publications
  • V. K. Enterprises
    +91-9313558510 V. K. Enterprises https://www.indiamart.com/vkenterprises-delhi/ Guaranteeing complete safety through our range of products, we are well renowned manufacturer and exporter of superior quality sports helmets. Our range include: cricket helmet, skating helmet, ice skating helmet, hockey helmet, etc. About Us Established to provide complete customer satisfaction, we are world renowned manufacturer and exporter of a range of sports equipment and sports helmet. We are also renowned vendors of prestigious Hero Group of Industries and bring forth a wide range of sporting equipment. Our products assure us of higher durability, reliability and offer better protection to the players. Our full range includes: cricket helmet, skating helmet, ice skating/ hurley helmet, hockey helmet, horse riding helmet, cycling helmet, cricket leg guard, cricket thigh guard, cricket arm guard, cricket equipments, hockey equipments, skating equipments. Conducting intensive R & D process for two years have enabled us to establish our foothold in the industry. Our team of professionals are engrossed in the constant innovation and product development process. In all our endeavors we are guided by our founder Mr. V.K. Aggarwal, who has more than 30 years of experience in this industry. For more information, please visit https://www.indiamart.com/vkenterprises-delhi/profile.html NEW ITEMS P r o d u c t s & S e r v i c e s Cricket Helmets Cricket Moulded Leg Guards Hurling Helmets Kit Bags P r o OTHER PRODUCTS: d u c t s & S e r v i c e s Cycle & Skating Helmets Club Sporting Gloves Chest Guard Hockey Helmets P r o OTHER PRODUCTS: d u c t s & S e r v i c e s Horse Riding Helmet Sports T-Shirt Knee Pads Horse Riding Helmets F a c t s h e e t Nature of Business :Manufacturer Total Number of Employees :26 to 50 People CONTACT US V.
    [Show full text]
  • Hockey Helmets Miss the Mark on Concussions
    CHICAGOLAWBULLETIN.COM TUESDAY, APRIL 7, 2015 ® Volume 161, No. 67 Hockey helmets miss the mark on concussions recent study on the study is that all 32 helmets were from advertisements and to concussion-protec - previously certified as safe by donate $500,000 worth of hockey tion capacities of the Hockey Equipment LEX SPORTIVA equipment to charity. hockey helmets Certification Council (HECC). Interestingly, the Bauer Re-AKT produced signifi - The NCAA, NHL and USA helmet, which is sold in two Acantly negative results. Hockey all require that players styles that are among the most Researchers at Virginia Tech use helmets that are certified by expensive on the market, tested all 32 helmets that can be the HECC. In addition, the NHL received a single star in the purchased on the market and also mandates that players’ TIMOTHY Virginia Tech study. found that across the board, helmets meet the requirements L. E PSTEIN This result is consistent with a hockey helmets are poor in their of the Canadian Standards larger trend of price indifference ability to protect players from Association (CSA). throughout the hockey helmet the risk of concussions. Part of the discrepancy can be study. The researchers admitted In preparation for the study, explained by the fact that while Timothy L. Epstein is a partner and surprise in finding that their the researchers discovered that both the HECC and the CSA chairman of the sports law practice study produced no correlation male and female hockey players require helmets to withstand G- group at SmithAmundsen LLC. He also between price and level of — bantam level through college force levels that will prevent serves as an adjunct professor at protection that helmets provided — sustain an average of 227 hits skull fractures and other serious Loyola University Chicago School of against concussions.
    [Show full text]
  • Analysis of the Protective Capacity of Ice Hockey Helmets in a Concussion Injury Reconstruction
    IRC-14-17 IRCOBI Conference 2014 Analysis of the protective capacity of ice hockey helmets in a concussion injury reconstruction Andrew Post, Clara Karton, T. Blaine Hoshizaki, Michael D. Gilchrist Abstract Concussion unfortunately is a common and serious injury in ice hockey, involving a large number of youth and pro level athletes. The purpose of this research was to examine the efficacy of ten ice hockey helmet models in protecting players. A head impact during a professional ice hockey game that resulted in a documented concussion was reconstructed in the laboratory. The impact parameters were determined from video analysis of the incident that resulted in a concussion. The event was reconstructed in the laboratory using mechanical impacts and finite element modelling. The performance of the ice hockey helmets was measured using peak linear and rotational acceleration. The acceleration time histories were used as input to the University College Dublin Brain Trauma Model to determine the maximum principal strain. The results demonstrated that the shell and liner design of the helmets influence the motion of the head during an impact. Low responses in peak resultant linear acceleration do not reflect low responses in peak resultant rotational acceleration. When comparing the helmets using maximum principal strain as the metric, there were differences between helmet models not reflected in the kinematic data. This suggests that the magnitude of strain is not fully represented by peak resultant linear and rotational acceleration. In addition, while the differences between the helmets’ protective capacity were statistically significant, those differences would not have appreciably affected the likelihood of concussive injury in this reconstruction.
    [Show full text]
  • Ice Hockey Fitting Guide
    Ice Hockey Equipment Fitting Guide - Fit to Play the Right Way Brought to you by: coachsafely.org www.helmetfitting.com follow us @coachsafely and @Helmetfitting All material copyright: CoachSafely Foundation and Helmetfitting.com YOUTH AGE GROUPS: 8-and-Under (mite), 10-and-Under (squirt), 12-and-Under (peewee), 14-and-Under (bantam) Each player is personally responsible to wear protective equipment for all games, warm-ups and practices. Such equipment should include gloves, shin pads, shoulder pads, elbow pads, hip pads or padded hockey pants, protective cup, tendon pads plus all head protective equipment as required by USA Hockey rules. It is recommended that all protective equipment be designed specifically for ice hockey. HELMETS A hockey helmet’s primary purpose is to prevent a skull fracture, not a concussion. A skull fracture or other blunt impact can be dissipated across the shells and foams of a helmet, but a concussion occurs due to rotational forces. What this means is, if your head moves rapidly, such as in a whiplash situation, a concussion may occur even without any impact to the head. WARNING Ice hockey is a collision sport that is dangerous. Hockey helmets afford no protection from neck or spinal injury. Severe head, brain or spinal injuries including paralysis or death may occur despite using a hockey helmet. Youth athletes should wear youth helmets. All players, including goalkeepers are required to properly wear a Hockey Equipment Certification Council (HECC) approved helmet as designed by the manufacturer and with no alterations and chin strap properly fastened. All youth through college players, including goalkeepers, are required to wear full facial protection—wire cage, full shield or combination mask certified by HECC, plus any chin protection that accompanies the face mask.
    [Show full text]
  • Angular Acceleration Responses of American Football, Lacrosse and Ice Hockey Helmets Subject to Low‐Energy Impacts
    IRC-14-18 IRCOBI Conference 2014 Angular Acceleration Responses of American Football, Lacrosse and Ice Hockey Helmets Subject to Low‐Energy Impacts R. Anna Oeur, Katrina Zanetti, T. Blaine Hoshizaki Abstract Neurological complications associated with sports‐related brain trauma have been a recent concern and focus of research. In turn, sensor technologies have been developed to count head impacts during sports. Low‐level impacts present a low risk for concussion but are implicated in long‐term neurological conditions. The effectiveness of helmets at managing angular acceleration at this energy level is unknown. The objective of this research was to examine the ability of American football, lacrosse and hockey helmets and the bare head to manage angular accelerations for low‐level impacts (20g). A 50th percentile Hybrid III headform was impacted using a pendulum system at nine centric and non‐centric impact sites. Linear and angular accelerations were recorded using nine single‐axis accelerometers arranged in a 3‐2‐2‐2 array. A consistent trend across centric and non‐centric impact sites was observed for peak angular acceleration: football helmets produced the lowest levels, followed by the bare headform, with the lacrosse and hockey helmets producing the highest values. At the crown site, however, the football helmet produced the highest angular acceleration. Peak angular acceleration at low impact energies was influenced by the type of helmet and impact condition. While there is little risk in terms of linear acceleration for low‐level impacts, angular accelerations approach a 25% risk of concussion. Helmets must be tested and designed to manage these impacts.
    [Show full text]
  • Proper Fit and Maintenance of Ice-Hockey Helmets
    INJURY PREVENTION & PERFORMANCE ENHANCEMENT Patrick Sexton, EdD, ATC, CSCS, Column Editor Proper Fit and Maintenance of Ice-Hockey Helmets Tamara C. Valovich McLeod, PhD, ATC, CSCS • Arizona School of Health Sciences NE OF OUR RESPONSIBILITIES as certified Although most ice-hockey helmets are sized based athletic trainers and therapists is to make on hat size (circumference of the head measured 1 in. O the competitive environment as safe as above the eyebrows), it is still necessary for the clini- possible in the hope of reducing the likeli- cian, parent, or coach to make sure the helmet is fitted hood of injury.1 According to the NATA role-delineation properly (see the sidebar).5-7 When one is fitting an study, a subcategory of injury prevention is selecting ice-hockey helmet, the athlete’s hair should be wet to and properly fitting protective equipment.1 In addi- simulate the sweat that he or she would produce during tion, athletic trainers must take steps to ensure that a practice or game. The helmet should be placed on high-quality athletic equipment is being purchased, the athlete with the chin strap fastened and the face constantly worn, maintained, and reconditioned.2 The mask, if mandated, secured. Once the helmet is on, purpose of this column is to describe the proper fit it should sit level on the athlete’s head (Figure 1). The and maintenance of ice-hockey helmets and provide clinician should check that the helmet sits no lower on clinicians educational resources to teach athletes about the forehead than one to two finger widths above the proper care of their equipment.
    [Show full text]
  • Effect of Protective Helmets on Visual and Sensory Performance
    EFFECT OF PROTECTIVE HELMETS ON VISUAL AND SENSORY PERFORMANCE By Michelle Rebecca Kramer Senior Honors Thesis Exercise and Sport Science University of North Carolina at Chapel Hill April 11, 2016 Approved: __________________________________________ Jason Mihalik, PhD, Thesis Advisor Erin Wasserman, PhD, Reader Elizabeth Teel, MS, Reader ABSTRACT MICHELLE REBECCA KRAMER: Effect of Protective Helmets on Visual and Sensory Performance (Under the direction of Jason P. Mihalik) Current helmet testing does not consider implications on ability to see and respond, which is key to reducing injury risk. The purpose was to determine the effect of athletic headgear (i.e., football, lacrosse, and ice hockey helmets) on visual and sensory performance, as measured by scores on the Senaptec Sensory Station. Subjects were assessed on visual clarity, contrast sensitivity, depth perception, near-far quickness, target capture, perception span, multiple object tracking, eye-hand coordination, go/no go, and hand reaction time via the computer based system under helmeted and unhelmeted conditions. Participants performed significantly worse on eye- hand coordination (p=0.01) and go/no go (p<0.01) assessments when wearing a helmet. Hockey helmets significantly affected visual clarity (p=0.01) and hand reaction time (p<0.01), but football and lacrosse helmets did not. Visual training with helmets should be considered to try to combat some of these visual deficits. ii TABLE OF CONTENTS LIST OF TABLES .........................................................................................................................
    [Show full text]
  • Analysis of Current Traumatic Brain Injuries, Concussion Rates, Helmet
    Analysis of current Traumatic Brain Injuries, concussion rates, helmet protection standards, helmet design deficiencies, and suggestions for basic helmet improvement in youth ice hockey and other contact sports David J Millar Jan 2011 DRAFT 8.1 © 2011 David Millar and US Youth Sports US Youth Sports nor any of their employees makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information herein. Table of contents Abstract..................1 Materials reviewed.2 Analysis..................3 Helmets...................9 Facial Protection...19 Chinstraps.............22 Results..................24 Conclusion............24 Footnotes..............26 Abstract Background Ice hockey is a contact sport with an implied risk of injury due to contact with the ice, boards, players, goals, and other equipment. Helmets and facial protection will not eliminate the possibility of all injuries but they have been shown to reduce some injuries. Purpose To evaluate the current helmet standards used in ice hockey as compared to other contact sports. The current research in concussions (TBI). The current design, materials and processes used in the production of helmets. Recommend design and standards changes to reduce the probability of TBI, head, neck and facial injuries in youth ice hockey. These changes have applications in football and lacrosse as well. Methods Current research materials were reviewed and helmets were purchased for testing, measurements, and evaluation of construction. Results Design deficiencies and areas for improvement were noted in all contact sports helmets tested. The probability of TBI AIS4 can be reduced by > 6 percentage points. 1 Conclusion Changing the design, liner materials, construction, manufacturing, and assembly techniques that are currently available and used in helmet manufacturing today along with raising the helmet testing standards can reduce the probability of TBI and mTBI in contact sports.
    [Show full text]
  • Projectile Impact Testing of Ice Hockey Helmets: Headform Kinematics and Dynamic Measurement of Localized Pressure Distribution
    IRC-14-16 IRCOBI Conference 2014 Projectile Impact Testing of Ice Hockey Helmets: Headform Kinematics and Dynamic Measurement of Localized Pressure Distribution. Ryan Ouckama, David J. Pearsall Abstract Ice hockey pucks are rubber projectiles that can carry >180 J of kinetic energy during a slap shot. When striking the temporal region of the skull, pressures capable of fracture can occur. Despite this risk, there is very little research on the topic. In this study, five helmet models, representing various material and shell compositions, were fit to a Hybrid III headform and subjected to puck impact at 24.2 m/s (PI24) and 33 m/s (PI33). The linear and angular kinematics of the headform and dynamic load distribution at the contact site were measured using 9 accelerometers and 25 force sensors. The cumulative strain damage measure (CSDM) was calculated using the SIMon (Simulated Injury Monitor) brain model. Thick‐shelled HDPE helmets using different EPP foams tended to perform similarly, whereas the combination of thin polycarbonate shell and lightweight foam performed poorly, particularly at PI33, for both acceleration‐derived values and CSDM. Helmets with VN liners appeared to exhibit reduced CSDM as compared to models with EPP liners or a plastic cylinder array. The quantification of this impact type provides insight into current helmet effectiveness during this impact modality which may place players at risk of mTBI injury or scalp lacerations. Keywords Ice Hockey, Helmet, Impact, Injury. I. INTRODUCTION Mandatory helmet use and the establishment of national safety standards were introduced to the sport of ice hockey following public outcry due to the high frequency of severe head injuries in the sport during the 1960s and 1970s.
    [Show full text]
  • Helmet Construction Influences Brain Strain Patterns for Events Causing Concussion in Youth Ice Hockey
    IRC-17-33 IRCOBI Conference 2017 Helmet Construction Influences Brain Strain Patterns for Events Causing Concussion in Youth Ice Hockey David A. Koncan, Roger Zemek, MD, Michael D. Gilchrist, Thomas B. Hoshizaki Abstract Two conventional ice hockey helmet liners were tested for head impact events documented to cause concussion in youth ice hockey (falls to the ice and boards). Impact parameters were established using real world cases of concussion in youth ice hockey to inform MADYMO simulations, which established a corridor of response representative of youth ice hockey impact events. Helmets were tested at two velocities on two surfaces (ice and boards), at a high and low velocity determined by the kinematic simulations. Helmets were evaluated based on impact kinematics and finite element metrics of maximum principal strains and cumulative strain damage measures using a scaled finite element model of the brain. The vinyl nitrile liner showed better performance at reducing rotational acceleration and velocity measures, whereas the expanded polypropylene liner performed better for reducing linear acceleration for most cases. The vinyl nitrile liner showed better performance in reducing maximum principal strain for impacts at and below 4 m/s, but showed signs of approaching the upper functional range at 4.5 m/s with increased strain compared to the expanded polypropylene liner. Keywords Concussion, helmets, youth ice hockey, head impact, finite element modelling I. INTRODUCTION Helmets play an important role in ice hockey, protecting participants who sustain impacts to the head resulting from falling onto the ice and boards, from collisions with other players, or from stick and puck impacts.
    [Show full text]
  • Time Series Measurement of Force Distribution in Ice Hockey Helmets
    Time Series Measurement of Force Distribution in Ice Hockey Helmets during Varying Impact Conditions Ryan Andrew Ouckama Department of Kinesiology and Physical Education, Faculty of Education, McGill University Montreal, Quebec, Canada March 2013 A thesis submitted to McGill University in partial fulfillment of the requirements of the degree of Doctor of Philosophy in Kinesiology and Physical Education Ryan Ouckama, 2013. All rights reserved. ii ABSTRACT Modern sport helmets have been effective in reducing catastrophic head injuries such as skull fracture and subdural hematoma; yet, the high prevalence of minor traumatic brain injuries (mTBI) is an unresolved public health concern. Consequently, there is a need for greater scrutiny in a helmet’s ability to mitigate collision forces that may correspond to mTBI risk. Current safety standards primarily assess a helmet’s ability to minimize the whole head’s peak acceleration during blunt impacts. Absent are dynamic measures local to the impact site itself due to the technical challenge to spatial map high impact force magnitudes with high temporal resolution. Inclusion of the latter measures may enhance the functional assessment of helmets. Thus, the aim of this research was to develop a localized impact mapping system (LIMS) for placement between the helmet and head interface and then to utilize the LIMS to evaluate the mechanical behaviour of various padding foams and helmets during controlled headform drop and projectile collision tests. Interposed between the helmet shell/padding and head surface, this LIMS consists of an array of discrete, thin force sensors connected to a compact signal conditioner and high speed data acquisition digital recorder.
    [Show full text]
  • The Avoidability of Head and Neck Injuries in Ice Hockey: an Historical Review N Biasca, S Wirth, Y Tegner
    410 Br J Sports Med: first published as 10.1136/bjsm.36.6.410 on 1 December 2002. Downloaded from REVIEW The avoidability of head and neck injuries in ice hockey: an historical review N Biasca, S Wirth, Y Tegner ............................................................................................................................. Br J Sports Med 2002;36:410–427 The number of minor traumatic brain injury (mTBI), (mTBI), even called cerebral concussion.7–20 cerebral concussions, is increasing and cannot be Parallel to this, in the period 1982–1996, there was world wide a persistent number of 17 major eliminated by any kind of equipment. Prevention spinal injuries a year.21–26 These epidemiological strategies, such as the introduction of “checking from data are very worrying and need to be analysed. behind” rules have become effective in decreasing the The development of protective equipment re- quires a sound understanding of the injury number of severe spinal injuries. A new “head mechanism, location, and type as well as the checking” rule should reduce mTBI in the same way in tissue response to stress, fatigue, and displace- the following years. Mouthguards should be mandatory ment velocity or acceleration. There is also the necessity to continuously analyse the epidemio- as an effective device for the prevention of dental and logical data with respect to the evolution of orofacial injuries, as well as reducing the incidence and protective devices and ice hockey rules. The use of severity of mTBI. A new internet database system, the a uniform computerised www.ISIS (International Sports Injury System) based database is one way International Sports Injury System (ISIS) should improve of detecting changes in the epidemiological epidemiological analysis of head, face, and spinal pattern early on.27 injuries worldwide.
    [Show full text]