Risk Factors for Lower Extremity Overuse Injuries in Female Youth Soccer Players.

Background: Youth soccer injuries are common and of increasing concern, with sport specialization occurring at younger ages. Limited research is available regarding overuse injuries and risk factors in young female athletes.

Purpose: To identify the number and rate of overuse injuries in female soccer players (ages 12-15 years), describe the anatomic location and type of injury, and evaluate contributing risk factors.

Is Knee Separation During a Drop Jump Associated With Lower Extremity Injury in Adolescent Female Soccer Players?

Background: Knee injuries are common in older adolescent and adult female soccer players, and abnormal valgus knee appearance characterized by low normalized knee separation (NKS) is a proposed injury risk factor. What constitutes normal NKS in younger adolescents and whether low NKS is an injury risk factor are unknown.

Purpose: To determine the normal range of NKS using a drop-jump test in female perimenarchal youth soccer players and whether low NKS contributes to lower extremity injuries or knee injuries.

Shoe and Field Surface Risk Factors for Acute Lower Extremity Injuries Among Female Youth Soccer Players.

Objective: To describe acute lower extremity injuries and evaluate extrinsic risk factors in female youth soccer.

Design: Nested case-control study.

Setting: Youth soccer clubs in Seattle, WA.

Distal radius malunion and forearm rotation: a cadaveric study.

Background Malunions following distal radius fractures are common, with shortening, translation, and rotation occurring. The patients frequently lose forearm rotation, but there is no data to indicate whether this is due to mechanical misalignment between the radius and the ulna or to contracture of the soft tissues. Material and Methods Seven fresh cadaveric specimens were used to determine the loss of forearm rotation with varying simulated distal radius fracture malalignment patterns.

Strength and jump biomechanics of elite and recreational female youth soccer players.

Context: Most researchers investigating soccer injuries have studied elite athletes because they have greater athletic-exposure hours than other athletes, but most youth participate at the recreational level. If risk factors for injury vary by soccer level, then recommendations generated using research with elite youth soccer players might not generalize to recreational players.

Objective: To examine injury risk factors of strength and jump biomechanics by soccer level in female youth athletes and to determine whether research recommendations based on elite youth athletes could be generalized to recreational players.

Risk factors for pelvic fractures in lateral impact motor vehicle crashes.

Lateral impact motor vehicle crashes account for over 10% of all crashes and are more likely to result in pelvic fractures than frontal crashes. We performed a case control study of lateral impact motor vehicle crashes using the 1995-2004 National Accident Sampling System Crashworthiness Data System to determine occupant and vehicle risk factors for pelvic fractures. Cases (N=728) were occupants involved in a near-side lateral impact crash who experienced a pelvic fracture and controls were occupants (N=5710) who did not experience a pelvic fracture.

Biomechanic analysis of trapeziectomy, ligament reconstruction with tendon interposition, and tie-in trapezium implant arthroplasty for thumb carpometacarpal arthritis: a cadaver study.

Purpose: Thumb carpometacarpal joint arthritis has been commonly treated with some combination of resection of the trapezium and interposition of a spacer using either a biologic or artificial material plus tenodesis to reconstruct the volar oblique ligament. The purpose of this study was to evaluate the biomechanic stability of the classic ligament reconstruction with tendon interposition (LRTI) or without tendon interposition compared with a newly developed 1-piece silicone trapezium implant.

Methods: Twelve cadaver arm specimens had the following procedures: resection of the trapezium, tendon interposition, ligament reconstruction, LRTI, and the silicone implant.

Reducing primary and secondary impact loads on the pelvis during side impact.

Objective: The objective of the study was to determine which vehicle factors are significantly related to pelvic injury in side impact collisions. Identification of relevant parameters could aid in the reduction of these injuries.

Method: Side impact crashes from the CIREN database were separated into those in which the occupant sustained a pelvic fracture and those in which no pelvic fracture occurred, although all occupants had serious injuries.

Reproductive hormone effects on strength of the rat anterior cruciate ligament.

The material properties of the anterior cruciate ligament (ACL) in female rats with normal estrous cycles were compared to those regulated by oral contraceptive steroids. Forty female Sprague-Dawley rats were divided into two groups: an experimental group received daily ethinylestradiol and levonorgestrel in a dosing model designed to simulate a typical oral contraception regime in humans, while a control group received daily oral placebo. After eight cycles, six rats from each group underwent daily phlebotomy to measure serum estradiol and progesterone levels over the course of a single 5-day estrous cycle.

The role of door orientation on occupant injury in a nearside impact: a CIREN, MADYMO modeling and experimental study.

Objective: This study addressed the effects of vehicle height mismatch in side impact crashes. A light truck or SUV tends to strike the door of a passenger car higher causing the upper border to lead into the occupant space. Conversely, an impact centered lower on the door, from a passenger car, causes the lower border to lead.

Parametric analysis of vehicle design influence on the four phases of whiplash motion.

Objective: The objective is to establish a basis for motor vehicle test requirements that measure component contributions to Whiplash Associated Disorders (WAD).

Methods: Selected vehicle design features are evaluated with regard to their relative contributions to WAD measures. The motion of the occupant cervical spine associated with WAD is divided into four phases: retraction, extension, rebound, and protraction.

Factors affecting pelvic and thoracic forces in near-side impact crashes: a study of US-NCAP, NASS, and CIREN data.

The goal of this study was to identify variables related to vehicle design which are associated with pelvic and thoracic accelerations as measured by the driver's (near side) crash dummy during new car assessment program (NCAP) testing of motor vehicles. Vehicle specific parameters were analyzed using NCAP side impact test results. Data from national automotive sampling system, crashworthiness data system (NASS-CDS) and crash injury research and engineering network (CIREN) (both National Highway Traffic Safety Administration (NHTSA) injury databases) were assessed to confirm NCAP test observations.

Biomechanical properties of shoes and risk of falls in older adults.

Objectives: To determine the relationships between the biomechanical properties of shoes worn in a cohort of healthy older adults and the risk of falling.

Design: Nested case-control study, comparing biomechanical measurements of shoes worn by those who reported a fall with measurements of shoes worn by age- and sex-matched nonfallers engaged in broadly similar activities.

Setting: On-site measurements where falls occurred.

Footwear style and risk of falls in older adults.

Objectives: To determine how the risk of a fall in an older adult varies in relation to style of footwear worn.

Design: Nested case-control study.

Setting: Group Health Cooperative, a large health maintenance organization in Washington state.

A comparison of injury criteria used in evaluating seats for whiplash protection.

A protocol has been proposed for testing seats for whiplash protection, however injury criteria have not yet been chosen. Assuming that whiplash symptoms arise from non-physiological motions of vertebral segments, we determined the ability of proposed criteria to predict peak individual vertebral displacements. Twenty-eight volunteers were subjected to rear impacts while seated in a car seat with head restraint, mounted onto a sled.

Effect of loading rate on endplate and vertebral body strength in human lumbar vertebrae.

Previous studies have implied that increases in loading rate resulted in changes in vertebral mechanical properties and these changes were causative factors in the different fracture types seen with high-speed events. Thus many researchers have explored the vertebral body response under various loading rate conditions. No other study has investigated the role of the endplate in high-speed vertebral injuries.

Traumatic brain injury and automotive design: making motor vehicles safer.

Background: Traumatic brain injury (TBI) remains a major public health problem in the United States. Identifying and modifying vehicle designs associated with TBI will have a significant impact on the frequency and severity of TBI in motor vehicle crashes (MVCs). Our objective, therefore, was to identify interior vehicle contact points associated with severe TBI (head Abbreviated Injury Scale score > 3) among drivers and determine the extent to which modifications of these contact points impact the likelihood of severe TBI.

Biomechanical function of the distal radioulnar and ulnocarpal wrist ligaments.

Purpose: This study was designed to provide quantitative information concerning the functions of the ligaments that stabilize the distal radioulnar joint (DRUJ). This joint permits the radius to rotate around a nearly fixed ulna allowing supination and pronation of the hand. Understanding their function is important in developing procedures for reconstruction.

Triangular osteosynthesis and iliosacral screw fixation for unstable sacral fractures: a cadaveric and biomechanical evaluation under cyclic loads.

Objective: To conduct a biomechanical comparison of a new triangular osteosynthesis and the standard iliosacral screw osteosynthesis for unstable transforaminal sacral fractures in the immediate postoperative situation as well as in the early postoperative weight-bearing period.

Design: Twelve preserved human cadaveric lumbopelvic specimens were cyclicly tested in a single-limb-stance model. A transforaminal sacral fracture combined with ipsilateral superior and inferior pubic rami fractures were created and stabilized.

Internal loads in the cervical spine during motor vehicle rear-end impacts: the effect of acceleration and head-to-head restraint proximity.

Study Design: This study used rigid-body and finite-element models of forces in the cervical spine resulting from a rear-end motor vehicle impact based on data from 26 volunteer experiments.

Objectives: To define the magnitudes and directions of internal forces acting on the cervical spine during rear-end impact, and to determine the effects of increasing the impact acceleration and the initial position of the occupant's head with respect to the head restraint.

Summary Of Background Data: In a number of studies using volunteers or cadavers, the kinematics of the occupant during a rear-end impact related to "whiplash" of the cervical spine have been reported.

Femur fractures in relatively low speed frontal crashes: the possible role of muscle forces.

In a sample of relatively low speed frontal collisions (mean collision speed change of 40.7 kph) the only major injury suffered by the partly or fully restrained occupant was a femur fracture. However, femur load measurements from standardized barrier crash tests for similar vehicles at a greater speed change (mean of 56.