Assessment of Head Impacts and Muscle Activity in Soccer Using a T3 Inertial Sensor and a Portable Electromyography (EMG) System: A Preliminary Study

Heading the ball is an important skill in soccer. Head impacts are of concern because of the potential adverse health effects. Many elite players now wear GPS (that include inertial monitoring units) on the upper spine for location tracking and workload measurement. By measuring the maximum acceleration of the head and the upper spine, we calculated the acceleration ratio as an attenuation index for participants (n = 8) of different skill levels during a front heading activity. This would allow for in-field estimates of head impacts to be made and concussive events detected. For novice participants, the ratio was as high as 8.3 (mean value 5.0 ± 1.8), whereas, for experienced players, the mean ratio was 3.2 ± 1.5. Elite players stiffen the neck muscles to increase the ball velocity and so the torso acts as a support structure. Electromyography (EMG) signals that were recorded from the neck and shoulder before and after a training intervention showed a major increase in mean average muscle activity (146%, p = 3.39 × 10−6). This was accompanied by a major decrease in acceleration ratio (34.41%, p = 0.008). The average head-ball impact velocity was 1.95 ± 0.53 m/s determined while using optical motion capture. For this low velocity, the impact force was 102 ± 19 N, 13% of the published concussive force. The voluntary action of neck muscles decreases isolated head movements during heading. Coaches and trainers may use this evidence in their development of junior players.

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Pontomedullary lacerations and concomitant injuries: A review of possible underlying mechanisms

Srpski arhiv za celokupno lekarstvo ◽

10.2298/sarh1308542z ◽

2013 ◽

Vol 141 (7-8) ◽

pp. 542-547 ◽

Cited By ~ 1

Author(s):

Vladimir Zivkovic ◽

Slobodan Nikolic

Keyword(s):

Impact Force ◽

Spinal Column ◽

Force Transmission ◽

Concomitant Injuries ◽

Head Impacts ◽

Shock Absorbers ◽

Exact Position ◽

Underlying Mechanisms ◽

The Impact ◽

Upper Spine

Anatomically, brainstem is constituted of medulla oblongata, pons and mesencephalon. Traumatic lesions of brainstem most commonly occur on pontomedullary junction. There are several possible mechanisms of pontomedullary lacerations. The first mechanism includes impact to the chin, with or without a skull base fracture, and most often leads to this fatal injury, due to impact force transmission through the jawbone and temporomandibular joint. The second mechanism includes lateral and posterior head impacts with subsequent hinge fractures, where occurrence of pontomedullary lacerations in these cases may depend on the energy of impact, as well as on the exact position of the fracture line, but less so on the head?s movement. The third mechanism includes frontoposterior hyperextension of the head, due to frontal impact, concomitant with fractures or dislocations of upper spine. In the fourth mechanism, there is an absence of direct impact to the head, due to the indirect force of action after feet or buttocks?first impact. Most of these cases are accompanied by ring fractures as well. In situations such as these, the impact force is transmitted up the spinal column and upper vertebrae, and telescopically intruded into the skull, causing brainstem laceration. The jawbone and other facial bones can act as shock absorbers, and their fracture could diminish the energy transfer towards the skull and protect the brain and brainstem from injury. In all the cases with pontomedullary laceration posterior neck dissection should be performed during the autopsy, since upper spine injuries are often associated with this type of injury.

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Role of Occupational Footwear and Prolonged Walking on Lower Extremity Muscle Activation during Maximal Exertions and Postural Stability Tasks

Biomechanics ◽

10.3390/biomechanics1020017 ◽

2021 ◽

Vol 1 (2) ◽

pp. 202-213

Author(s):

Harish Chander ◽

Sachini N. K. Kodithuwakku Arachchige ◽

Alana J. Turner ◽

Reuben F. Burch V ◽

Adam C. Knight ◽

...

Keyword(s):

Lower Extremity ◽

Muscle Activity ◽

Repeated Measures ◽

Postural Stability ◽

Muscle Activation ◽

Medial Gastrocnemius ◽

Lower Extremity Muscle ◽

Prolonged Duration ◽

The Mean ◽

The Impact

Background: Occupational footwear and a prolonged duration of walking have been previously reported to play a role in maintaining postural stability. The purpose of this paper was to analyze the impact of three types of occupational footwear: the steel-toed work boot (ST), the tactical work boot (TB), and the low-top work shoe (LT) on previously unreported lower extremity muscle activity during postural stability tasks. Methods: Electromyography (EMG) muscle activity was measured from four lower extremity muscles (vastus medialis (VM), medial hamstrings (MH), tibialis anterior (TA), and medial gastrocnemius (MG) during maximal voluntary isometric contractions (MVIC) and during a sensory organization test (SOT) every 30 min over a 4 h simulated workload while wearing ST, TB, and LT footwear. The mean MVIC and the mean and percentage MVIC during each SOT condition from each muscle was analyzed individually using a repeated measures ANOVA at an alpha level of 0.05. Results: Significant differences (p < 0.05) were found for maximal exertions, but this was limited to only the time main effect. No significant differences existed for EMG measures during the SOT. Conclusion: The findings suggest that occupational footwear type does not influence lower extremity muscle activity during both MVIC and SOT. Significantly lower muscle activity during maximal exertions over the course of the 4 h workload was evident, which can be attributed to localized muscular fatigue, but this was not sufficient to impact muscle activity during postural stability tasks.

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Neck Muscle Responses to Stimulation of Monkey Superior Colliculus. II. Gaze Shift Initiation and Volitional Head Movements

Journal of Neurophysiology ◽

10.1152/jn.2002.88.4.2000 ◽

2002 ◽

Vol 88 (4) ◽

pp. 2000-2018 ◽

Cited By ~ 64

Author(s):

Brian D. Corneil ◽

Etienne Olivier ◽

Douglas P. Munoz

Keyword(s):

Superior Colliculus ◽

Neck Muscles ◽

Head Movements ◽

Emg Activity ◽

Neck Muscle ◽

Gaze Shift ◽

Antagonist Muscles ◽

Agonist And Antagonist ◽

Agonist And Antagonist Muscles ◽

Stimulation Of

We report neck muscle activity and head movements evoked by electrical stimulation of the superior colliculus (SC) in head-unrestrained monkeys. Recording neck electromyography (EMG) circumvents complications arising from the head's inertia and the kinetics of muscle force generation and allows precise assessment of the neuromuscular drive to the head plant. This study served two main purposes. First, we sought to test the predictions made in the companion paper of a parallel drive from the SC onto neck muscles. Low-current, long-duration stimulation evoked both neck EMG responses and head movements either without or prior to gaze shifts, testifying to a SC drive to neck muscles that is independent of gaze-shift initiation. However, gaze-shift initiation was linked to a transient additional EMG response and head acceleration, confirming the presence of a SC drive to neck muscles that is dependent on gaze-shift initiation. We forward a conceptual neural architecture and suggest that this parallel drive provides the oculomotor system with the flexibility to orient the eyes and head independently or together, depending on the behavioral context. Second, we compared the EMG responses evoked by SC stimulation to those that accompanied volitional head movements. We found characteristic features in the underlying pattern of evoked neck EMG that were not observed during volitional head movements in spite of the seemingly natural kinematics of evoked head movements. These features included reciprocal patterning of EMG activity on the agonist and antagonist muscles during stimulation, a poststimulation increase in the activity of antagonist muscles, and synchronously evoked responses on agonist and antagonist muscles regardless of initial horizontal head position. These results demonstrate that the electrically evoked SC drive to the head cannot be considered as a neural replicate of the SC drive during volitional head movements and place important new constraints on the interpretation of electrically evoked head movements.

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Head Movements in Flies (Calliphora) Produced by Deflexion of the Halteres

Journal of Experimental Biology ◽

10.1242/jeb.85.1.43 ◽

1980 ◽

Vol 85 (1) ◽

pp. 43-60 ◽

Cited By ~ 2

Author(s):

DAVID C. SANDEMAN ◽

H. MARKL

Keyword(s):

Cerebral Ganglion ◽

Neck Muscles ◽

Head Movements ◽

Central Projections ◽

Sensory Axons ◽

One To One

1. The heads of resting flies will twitch to the side if the haltere is deflected rapidly forwards. Head movements are always away from the stimulated haltere and do not occur if the haltere is deflected up, down or backwards. 2. The anatomy and action of the neck muscles is described. 3. Cobalt fills of the whole haltere nerve show that the sensory axons project to the neuropiles of the ipsi- and contralateral pro- and mesothoracic neuropiles, to the ipsilateral metathoracic neuropiles and to the cerebral ganglion. 4. Cobalt fills of the nerves to the neck muscles and from the prosternal organs show that the central projections of these nerves end in the ipsilateral prothoracic neuropile. 5. Recordings from the motoneurones to the neck muscles show that they are phasically activated by forward deflexion of the halteres after a latency of 2.5–3 ms. Spikes in the motoneurones follow the vibration of the haltere, one to one, up to 200 Hz. 6. Recordings from the ipsilateral mesothoracic wing nerve (N. alae) show two large units which respond after a 2.5–3 ms latency to forward deflexion of the halteres. 7. Behavioural observations of walking flies show that the presence or absence of halteres has a small but nevertheless significant effect on the animals' ability to detect angular accelerations during walking or to orient with respect to gravity.

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Dual Mode Gait Sonification for Rehabilitation After Unilateral Hip Arthroplasty

Brain Sciences ◽

10.3390/brainsci9030066 ◽

2019 ◽

Vol 9 (3) ◽

pp. 66 ◽

Cited By ~ 3

Author(s):

Julia Reh ◽

Tong-Hun Hwang ◽

Gerd Schmitz ◽

Alfred Effenberg

Keyword(s):

Hip Arthroplasty ◽

Inertial Sensor ◽

Gait Training ◽

Control Group ◽

Walking Ability ◽

Dual Mode ◽

Gait Symmetry ◽

Home Based ◽

Mode Method ◽

The Impact

The pattern of gait after hip arthroplasty strongly affects regeneration and quality of life. Acoustic feedback could be a supportive method for patients to improve their walking ability and to regain a symmetric and steady gait. In this study, a new gait sonification method with two different modes—real-time feedback (RTF) and instructive model sequences (IMS)—is presented. The impact of the method on gait symmetry and steadiness of 20 hip arthroplasty patients was investigated. Patients were either assigned to a sonification group (SG) (n = 10) or a control group (CG) (n = 10). All of them performed 10 gait training sessions (TS) lasting 20 min, in which kinematic data were measured using an inertial sensor system. Results demonstrate converging step lengths of the affected and unaffected leg over time in SG compared with a nearly parallel development of both legs in CG. Within the SG, a higher variability of stride length and stride time was found during the RTF training mode in comparison to the IMS mode. Therefore, the presented dual mode method provides the potential to support gait rehabilitation as well as home-based gait training of orthopedic patients with various restrictions.

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Game-Related Impacts in High School Boys’ Lacrosse

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967119835587 ◽

2019 ◽

Vol 7 (4) ◽

pp. 232596711983558 ◽

Cited By ~ 2

Author(s):

Shane V. Caswell ◽

Patricia Kelshaw ◽

Andrew E. Lincoln ◽

Lisa Hepburn ◽

Reginald Dunn ◽

...

Keyword(s):

High School ◽

Rotational Velocity ◽

Linear Acceleration ◽

The United States ◽

Head Impact ◽

Level Of Evidence ◽

Cross Sectional ◽

Head Impacts ◽

Direct Head ◽

The Impact

Background: The rate of concussions in boys’ lacrosse is reported to be the third highest among high school sports in the United States, but no studies have described game-related impacts among boys’ lacrosse players. Purpose: To characterize verified game-related impacts, both overall and those directly to the head, in boys’ varsity high school lacrosse. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 77 male participants (mean age, 16.6 ± 1.2 years; mean height, 1.77 ± 0.05 m; mean weight, 73.4 ± 12.2 kg) were instrumented with sensors and were videotaped during 39 games. All verified game-related impacts ≥20 g were summarized in terms of frequency, peak linear acceleration (PLA), and peak rotational velocity (PRV). Descriptive statistics and impact rates per player-game (PG) with corresponding 95% CIs were calculated. Results: Overall, 1100 verified game-related impacts were recorded (PLA: median, 33.5 g [interquartile range (IQR), 25.7-51.2]; PRV: median, 1135.5 deg/s [IQR, 790.0-1613.8]) during 795 PGs. The rate for all verified game-related impacts was 1.38 impacts per PG (95% CI, 1.30-1.47). Of these, 680 (61.8%) impacts (PLA: median, 35.9 g [IQR, 26.7-55.5]; PRV: 1170.5 deg/s [IQR, 803.2-1672.8]) were directly to the head (impact rate, 0.86 impacts/PG [95% CI, 0.79-0.92]). Overall, midfielders (n = 514; 46.7%) sustained the most impacts, followed by attackers (n = 332; 30.2%), defenders (n = 233; 21.2%), and goalies (n = 21; 1.9%). The most common mechanisms for overall impacts and direct head impacts were contact with player (overall: n = 706 [64.2%]; head: n = 397 [58.4%]) and stick (overall: n = 303 [27.5%]; head: n = 239 [35.1%]), followed by ground (overall: n = 73 [6.6%]; head: n = 26 [3.8%]) and ball (overall: n = 15 [1.4%]; head: n = 15 [2.2%]). Direct head impacts were associated with a helmet-to-helmet collision 31.2% of the time, and they were frequently (53.7%) sustained by the players delivering the impact. Nearly half (48.8%) of players delivering contact used their helmets to initiate contact that resulted in a helmet-to-helmet impact. Players receiving a head impact from player contact were most often unprepared (75.9%) for the collision. Conclusion: The helmet is commonly used to initiate contact in boys’ high school lacrosse, often targeting defenseless opponents. Interventions to reduce head impacts should address rules and coaching messages to discourage intentional use of the helmet and encourage protection of defenseless opponents.

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Validation of an Inertial Sensor Algorithm to Quantify Head and Trunk Movement in Healthy Young Adults and Individuals with Mild Traumatic Brain Injury

Sensors ◽

10.3390/s18124501 ◽

2018 ◽

Vol 18 (12) ◽

pp. 4501 ◽

Cited By ~ 3

Author(s):

Lucy Parrington ◽

Deborah Jehu ◽

Peter Fino ◽

Sean Pearson ◽

Mahmoud El-Gohary ◽

...

Keyword(s):

Inertial Sensor ◽

Rotational Velocity ◽

Correlation Coefficients ◽

Head Movements ◽

Home Exercise ◽

Trunk Movement ◽

Percent Error ◽

Criterion Data ◽

Measurement Units ◽

Promising Solution

Wearable inertial measurement units (IMUs) may provide useful, objective information to clinicians interested in quantifying head movements as patients’ progress through vestibular rehabilitation. The purpose of this study was to validate an IMU-based algorithm against criterion data (motion capture) to estimate average head and trunk range of motion (ROM) and average peak velocity. Ten participants completed two trials of standing and walking tasks while moving the head with and without moving the trunk. Validity was assessed using a combination of Intra-class Correlation Coefficients (ICC), root mean square error (RMSE), and percent error. Bland-Altman plots were used to assess bias. Excellent agreement was found between the IMU and criterion data for head ROM and peak rotational velocity (average ICC > 0.9). The trunk showed good agreement for most conditions (average ICC > 0.8). Average RMSE for both ROM (head = 2.64°; trunk = 2.48°) and peak rotational velocity (head = 11.76 °/s; trunk = 7.37 °/s) was low. The average percent error was below 5% for head and trunk ROM and peak rotational velocity. No clear pattern of bias was found for any measure across conditions. Findings suggest IMUs may provide a promising solution for estimating head and trunk movement, and a practical solution for tracking progression throughout rehabilitation or home exercise monitoring.

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Scratch responses in normal cats: hindlimb kinematics and muscle synergies

Journal of Neurophysiology ◽

10.1152/jn.1990.64.6.1653 ◽

1990 ◽

Vol 64 (6) ◽

pp. 1653-1667 ◽

Cited By ~ 33

Author(s):

P. C. Kuhta ◽

J. L. Smith

Keyword(s):

Muscle Activity ◽

Knee Flexion ◽

Knee Extensor ◽

Head Movements ◽

Medial Gastrocnemius ◽

Emg Activity ◽

Circular Path ◽

Contact Phase ◽

Ankle Joints ◽

Flexor Muscles

1. Scratch responses evoked by a tactile stimulus applied to the outer ear canal were characterized in nine adult cats. Chronic electromyographic (EMG) electrodes were surgically implanted in selected flexor and extensor muscles of the hip, knee, and ankle joints to determine patterns of muscle activity during scratching. In some trials EMG records were synchronized with kinematic data obtained by digitizing high-speed cine film, and in one cat, medial gastrocnemius (MG) tendon forces were recorded along with EMG. For analysis the response was divided into three components: the approach, cyclic, and return periods. Usually scratch responses were initiated with the cat in a sitting position, but in some trials the animal initiated the response from a standing or lying posture. 2. During the approach period the hindlimb ipsilateral to the stimulated ear was lifted diagonally toward the head by a combination of hip and ankle flexion with knee extension. Hindlimb motions during the approach period were associated with sustained EMG activity in hip-flexor, knee-extensor (occasionally), and ankle-flexor muscles. Initial hindlimb motions were typically preceded by head movements toward the hindpaw, and at the end of the approach period, the head was tilted downward with the stimulated pinna lower than the contralateral ear. During the return period movements were basically the reverse of the approach period, with the hindpaw returning to the ground and the head moving away from the hindlimb. 3. During the cyclic period the number of cycles per response varied widely from 1 to 60 cycles with an average of 13 cycles, and cycle frequency ranged from 4 to 8 cycles/s, with a mean of 5.6 cycles/s. During each cycle the paw trajectory followed a fairly circular path, and the cycle was defined by three phases: precontact, contact, and postcontact. On average the contact phase occupied approximately 50% of the cycle and was characterized by extensor muscle activity and extension at the hip, knee, and ankle joints. The hindpaw contacted the pinna or neck at the base of the pinna throughout the contact phase, and paw contact typically resulted in a rostral motion of the head as the hindlimb extended. 4. The postcontact phase constituted approximately 24% of scratch cycle and was usually initiated by the onset of knee flexion. Ankle and then hip flexion followed knee flexion, and flexor muscles were active during the postcontact phase as the paw was withdrawn from the head. The precontact phase constituted approximately 26% of scratch cycle and was initiated by knee joint extension and knee-extensor activity.(ABSTRACT TRUNCATED AT 400 WORDS)

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Head Movements and Neck Muscle Activity During Air Combat Maneuvering

Aerospace Medicine and Human Performance ◽

10.3357/amhp.5425.2020 ◽

2020 ◽

Vol 91 (1) ◽

pp. 26-31 ◽

Cited By ~ 1

Author(s):

Roope Sovelius ◽

Maunu Mäntylä ◽

Heini Huhtala ◽

Juha Oksa ◽

Rasmus Valtonen ◽

...

Keyword(s):

Muscle Activity ◽

Muscular Activity ◽

Head Movements ◽

Neck Muscle ◽

Activity Levels ◽

Sitting Posture ◽

Field Of Vision ◽

Air Combat ◽

The Difference ◽

Neutral Posture

BACKGROUND: The aim of the study was to determine the characteristics of cervical muscle activity in different head movements when using helmet mounted display in air combat maneuvering.METHODS: Cervical EMG was measured with eight F/A-18 pilots using the Joint Helmet Mounted Cueing System (JHMCS) during air combat maneuvering. In-flight Gz acceleration and continuous head position were recorded. Muscular activity was compared between head movements in isolation and combined with torso movement. In addition, the effect of the direction of head movements and the use of head support of the ejection seat on muscle activity was determined.RESULTS: Muscular loading increased in the cervical flexors and extensors when using the torso during targeting beyond the field of vision in the neutral sitting posture; the difference was significant in the flexors, but activity levels were higher in the extensors. Cervical muscles are loaded to a lesser extent if the head is kept in a stable position during Gz loading. Muscular activity in the neck muscles was higher when the pilot was moving the head out of neutral posture rather than toward neutral posture. The use of the headrest as a support decreased muscle activity in the extensors, but resulted in higher activity in the flexor muscles.DISCUSSION: All analyzed conditions were significantly affected by an increase in Gz. An increase of muscle activity with torso movements is considered as a positive factor as it reflects maintained muscular support for the cervical spine. Presented results may be helpful when specific conditioning programs and cockpit ergonomics are developed for fighter pilots.Sovelius R, Mäntylä M, Huhtala H, Oksa J, Valtonen R, Tiitola L, Leino T. Head movements and neck muscle activity during air combat maneuvering. Aerosp Med Hum Perform. 2020; 91(1):26–31.

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Rewards and Impacts of Participation in a Gerontology Extension Program

Journal of Voluntary Action Research ◽

10.1177/0899764088017003-403 ◽

1988 ◽

Vol 17 (3-4) ◽

pp. 19-35

Author(s):

James G. Hougland ◽

Howard B. Turner ◽

Jon Hendricks

Keyword(s):

Public Service ◽

Social Participation ◽

General Pattern ◽

Self Esteem ◽

Voluntary Action ◽

Volunteer Work ◽

Public Service Agencies ◽

The Impact ◽

Service Agencies ◽

Extension Program

Because involvement in specific organizations typically is part of a general pattern of social participation, understanding the effects of activity in a particular realm is difficult. A 1985 program designed to make the skills of retired professionals available to public service agencies provided an opportunity to follow volunteers during various stages of their participation. It also permitted an assessment of the impact of their volunteer work in this program on changes in their morale, self-esteem, and alienation as well as the extent of their participation in other voluntary activities. It was predicted that the effects of voluntary action would vary according to the participants' reasons for volunteering, their perceptions of their success in serving the agencies, and the number of opportunities they had for demonstrating their competencies. Analysis suggested that participants responded positively but not dramatically to opportunities for meaningful social participation.

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