Biomedical subjects

Robin M Queen

Publications and source records attributed to Robin M Queen.

4 recordsLinked to original sources

PubMed2007

Forefoot loading during 3 athletic tasks.

BACKGROUND: Due to the popularity of soccer and the high incidence of injury among soccer players, it is valuable to know the effects of tasks like side cuts, crossover cuts, and forward acceleration on the foot. PURPOSE: To determine the differences in forefoot loading during three different athletic tasks. STUDY DESIGN: Descriptive laboratory study. METHODS: Thirty-six subjects (17 women and 19 men) were tested. Subjects ran a slalom-style agility course 5 times while plantar pressure data was collected at 100 Hz. Plantar pressure was recorded under both feet; however, a right-foot contact was used in the analysis of the side-cut task, a left-foot plant was used in the analysis of the crossover cut, and an average of the 3 steps of acceleration were used in the analysis. The peak pressure, contact area, and contact time for the entire foot were compared between the 3 tasks. The force and the force-time integral were obtained during 5 trials for each of the 3 tasks. The foot was divided into 8 masked regions, which were used to determine the loading patterns specifically in the forefoot. Each variable was analyzed using a 1 x 3 analysis of variance to determine differences between the three movement tasks in the forefoot region (a = .05). RESULTS: Significant differences in peak pressure, contact area, and contact time existed between the movement tasks when examining the entire foot. In addition, significant differences in the force-time integral and peak pressure in the forefoot existed between the movement tasks. The force-time integral was highest during the side cut in the medial forefoot, hallux, and the lesser toes, while the force-time integral was highest during the crossover cut in the middle forefoot and the lateral forefoot. Similarly, the peak pressure was highest during the side cut in the medial forefoot, hallux, and the lesser toes, while peak pressure was highest in the middle forefoot during the acceleration task and highest in the lateral forefoot during the crossover-cutting task. CONCLUSIONS: The results of this study demonstrated that the crossover cut places an increased load on the lateral portion of the forefoot, while the side-cut task places an increased load on the medial portion of the forefoot and the acceleration task places increased load on the middle forefoot. CLINICAL RELEVANCE: The differences in loading patterns based on athletic task are important for understanding potential injury mechanisms. In addition, this information could be important for defining a return to play protocol for athletes who have had specific injuries.

Adult↗

PubMed2006

The reliability and reproducibility of foot type measurements using a mirrored foot photo box and digital photography compared to caliper measurements.

UNLABELLED: The height of the medial longitudinal arch (MLA) is thought to be a predisposing factor to various lower extremity injuries. Discrepancy exists as to whether MLA height plays a role in injury prevention. The purpose of this study was to determine the intertester and intratester reliability, and the validity of the mirrored foot photo box (MFPB) and caliper measurements to radiographic measurements. METHODS: Thirty subjects with equal numbers of men and women were recruited. Both feet were tested (n=60) in a 90% weight bearing stance. A set of anatomic landmarks were palpated, marked, and measured using a caliper, MFPB, and radiographs. The protocol was completed by two testers on 2 days approximately 1 week apart. Intertester and intratester reliability were determined using the intraclass correlation coefficient (ICC)(2,k) and the ICC(2,1), respectively. Validity of both measurement techniques to radiographic measurements was determined using the ICC(2,k). RESULTS: The intertester reliability ranged from 0.991 to 0.577, while the intratester reliability ranged from 0.994 to 0.527, with first metatarsal angle being the only variable with poor reliability. Most variables demonstrated acceptable validity between the MFPB and the caliper measurements, and acceptable validity between the MFPB and calipers compared to radiographic measurements. The MFPB took 51.3+/-19.6s per foot while the caliper measurements averaged 227.4+/-68.9s to complete the measurements. DISCUSSION: The MFPB is as reliable as the caliper measurements, and offers better intertester reliability. Both the caliper and MFPB measurements demonstrated acceptable validity to radiographic measurements and testing time was reduced when using the MFPB compared to calipers.

Adolescent↗

PubMed2005

Repeatability of lower extremity kinetics and kinematics for standardized and self-selected running speeds.

INTRODUCTION: The purpose of this study was to determine the effects of self-selected versus standardized running speeds on within-day and between-day repeatability of lower extremity kinematics and kinetics for running gait. METHODS: Subjects (six female, six male, age 18-35) were recreational athletes with no lower extremity injuries. The following study variables were analyzed using the coefficient of variation (CV): the peak angles for knee internal rotation, external rotation, varus, valgus, flexion, and extension; peak angles for ankle dorsiflexion and plantar flexion; peak impact force and propulsive force; and peak anterior, posterior, medial, and lateral ground reaction forces (GRFs). Data for the entire stance phase were analyzed using the coefficient of multiple correlation (CMC) for the following variables: anterior-posterior, medial-lateral, and vertical GRF; the angles and angular velocities for knee internal-external rotation, valgus-varus, flexion-extension, and ankle dorsiflexion-plantar flexion. Each variable was analyzed using a 2 x 2 (speed x day) repeated measures ANOVA (alpha = 0.05). RESULTS: The within-day repeatability for all of the significantly different variables was greater than the between-day repeatability. For variables with a significant difference based on speed, the standardized running speed had greater repeatability. CONCLUSIONS: Within-day repeatability is generally greater than between-day repeatability. Running speed had little effect on the repeatability of any study variable. Having subjects run at a standardized speed may not be as important as previously thought.

Adolescent↗

PubMed2003

Theoretical study of the effect of ball properties on impact force in soccer heading.

PURPOSE: The objective of this study was to theoretically model, based on the Hertz contact theory, the impact force and contact time, as well as the linear and angular head accelerations during heading in children using two neck stiffness conditions (infinite and negligible stiffness). METHODS: The following mathematical model inputs were obtained: elastic modulus and mass of size three, four, and five balls at inflation pressures of 10, 12, and 14 psi, head modulus, head mass, head length, head and trunk moment of inertia, and the precontact ball velocity. The model outputs consisted of linear and angular head acceleration, impact force, contact time between the ball and head, and head impact criteria (HIC) all at the point of impact. Head mass and length were obtained as a percentage of body weight and height, respectively, based on age. RESULTS: With an increase in head mass, there is a decrease in the linear and angular head acceleration. With an increase in ball size, for the same head mass, there is an increase in the contact time between the head and the ball. Changing ball inflation pressure has little effect on the impact characteristics. Infinite neck stiffness decreased linear and angular head acceleration and HIC. CONCLUSION: Head mass and ball size have an effect on linear and angular head acceleration and contact time, respectively, whereas ball inflation pressure has a minimal effect on the impact characteristics. These results indicate that children should be restricted to using the appropriate ball for their age. Smaller head size within an age group is an underemphasized though important identifier of a player's injury risk.

Acceleration↗