Can a Boxer Engine Reduce Leg Injuries Among Motorcyclists? Analysis of Injury Distributions in Crashes Involving Different Motorcycles Fitted with Antilock Brakes (ABS)

Ankle injuries are common among young ballet dancers. These injuries may be attributed to ankle instability, insufficient lower extremity strength, and poor balance control. The purpose of this study was to explore whether these dancers exhibit functional ankle instability and if their single-leg balance control and lower extremity muscle strength correlate with functional ankle instability and leg injuries. Twenty-one ballet dancers (aged 10 to 17 years) participated in the study. The Cumberland Ankle Instability Tool (CAIT) questionnaire was used to examine functional ankle stability. Isometric muscle strength of the major lower extremity muscles was measured with a digital hand-held dynamometer. Single-leg balance was evaluated with the Y-Balance Test (YBT) and three Athletic Single-leg Stability Test (ASLST) protocols. Lower extremity injuries (self-reported) within 6 months after testing were recorded for correlation analyses. Both dominant and non-dominant ankles of the subjects exhibited functional ankle instability (26.71 and 25.71, respectively). Raising the center of mass (passé and first arm position) during the ASLST did not significantly affect balance performance (p = 0.104). However, removing extrinsic visual feedback significantly decreased single-leg balance (p < 0.001). In general, there was low correlation (r ≤ 0.49) between muscle strength, CAIT, YBT, and ASLST scores with lower extremity injuries. It is concluded that for young ballet dancers lower extremity muscle strength and single-leg balance control may not be strong contributing factors to leg injuries. This study also suggests that functional ankle stability may not have a direct impact on single-leg balance, and ballet dancers rely heavily on extrinsic visual feedback for single-leg balance control. Teachers might consider minimizing extrinsic feedback to challenge ballet dancers when implementing training protocols for single-leg balance control.

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COMMITTEE ON ACCIDENT PREVENTION

PEDIATRICS ◽

10.1542/peds.20.3.565 ◽

1957 ◽

Vol 20 (3) ◽

pp. 565-566

Author(s):

Keyword(s):

Emergency Care ◽

Surgical Care ◽

Electrical Energy ◽

Civil Defense ◽

Accident Prevention ◽

Skeletal Trauma ◽

Leg Injuries ◽

Arm Injuries ◽

Cervical Injuries ◽

Open Injuries

The Committee on Accident Prevention of the American Academy of Pediatrics, in co-operation with the Surgical Section of the same organization, has prepared the following statements to cover the emergency management of childhood skeletal trauma and burns. Both of these statements are endorsed by the Committee on Trauma of the American College of Surgeons and have been approved by the Federal Civil Defense Administration. EMERGENCY CARE OF CHILDHOOD SKELETAL TRAUMA 1. Evaluate and splint where they lie before moving. Do not attempt reduction. 2. Move cervical injuries face up on a rigid support with manual traction applied gently by cupping chin at the time of moving. Sand bags on either side of neck to prevent turning, if possible. 3. Spine injuries should not be flexed in transportation. 4. Lower leg injuries, transport in pillow strapped with belt. 5. Upper leg injuries, transport with both legs and trunk bound to board without circulatory interference. 6. Lower arm injuries, transport with splint such as rolled newspaper, gentle compression wrapping and sling. 7. Upper arm can be bound to chest with lower arm supporting in sling. 8. Open injuries or open wounds, cover with sterile dressing, do not dust with antibiotic, but systemic antibiotic is useful. Do not attempt to retract bone back under skin. Get to surgical care promptly. 9. Do not cover distal tips of extremities if it can be avoided thus allowing a circulation check to be made from time to time. EMERGENCY CARE OF BURNS 1. Burns are due to thermal agents (scalds or fire); chemical agents (battery acid or lye); radiation (sunburn or nuclear); and electrical energy.

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Analysis of Foot-Ankle-Leg Injuries in Various Under-Foot Impact Loading Environments with a Human Active Lower Limb (HALL) Model

Journal of Biomechanical Engineering ◽

10.1115/1.4052111 ◽

2021 ◽

Author(s):

Jing Huang ◽

Can Huang ◽

Fuhao Mo

Keyword(s):

Impact Loading ◽

Lower Limb ◽

Loading Rate ◽

External Rotation ◽

Loading Conditions ◽

Leg Injuries ◽

Limb Injuries ◽

Foot Loading ◽

Definition Of ◽

Neutral Posture

Abstract Lower limb injuries caused by under-foot impacts often appear in sport landing, automobile collision, and anti-vehicular landmine blasts. The purpose of the present study was to evaluate a foot-ankle-leg model of the Human Active Lower Limb (HALL) model, and used it to investigate lower leg injury responses in different under-foot loading environments to provide a theoretical basis for the design of physical dummies adapted to multiple loading conditions. The model was first validated in allowable rotation loading conditions, like dorsiflexion, inversion/eversion, and external rotation. Then, its sensitivity to loading rates and initial postures was further verified through experimental data concerning both biomechanical stiffness and injury locations. Finally, the model was used to investigate the biomechanical responses of the foot-ankle-leg region in different under-foot loading conditions covering the loading rate from sport landing to blast impact. The results showed that from -15° plantarflexion to 30° dorsiflexion, the neutral posture always showed the largest tolerance, and more than 1.5 times tolerance gap was achieved between neutral posture and dorsiflexion 30°. Under-foot impacts from 2 m/s to 14 m/s, the peak tibia force increased at least 1.9 times in all postures. Thus, we consider that it is necessary to include initial posture and loading rate factors in the definition of the foot-ankle-leg injury tolerance for under-foot impact loading.

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