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Background: Minimalistic footwear has garnered widespread interest in the running community, based largely on the premise that the footwear may reduce certain running-related injury risk factors through adaptations in running mechanics and foot strike pattern., Objective: To examine short-term adaptations in running mechanics among runners who typically run in conventional cushioned heel running shoes as they transition to minimalistic footwear., Design: A 2-week, prospective, observational study., Setting: A movement science laboratory., Participants: Nineteen female runners with a rear foot strike (RFS) pattern who usually train in conventional running shoes., Methods: The participants trained for 20 minutes, 3 times per week for 2 weeks by using minimalistic footwear. Three-dimensional lower extremity running mechanics were analyzed before and after this 2-week period., Main Outcome Measurements: Hip, knee, and ankle joint kinematics at initial contact; step length; stance time; peak ankle joint moment and joint work; impact peak; vertical ground reaction force loading rate; and foot strike pattern preference were evaluated before and after the intervention., Results: The knee flexion angle at initial contact increased 3.8° (P < .01), but the ankle and hip flexion angles at initial contact did not change after training. No changes in ankle joint kinetics or running temporospatial parameters were observed. The majority of participants (71%), before the intervention, demonstrated an RFS pattern while running in minimalistic footwear. The proportion of runners with an RFS pattern did not decrease after 2 weeks (P = .25). Those runners who chose an RFS pattern in minimalistic shoes experienced a vertical loading rate that was 3 times greater than those who chose to run with a non-RFS pattern., Conclusion: Few systematic changes in running mechanics were observed among participants after 2 weeks of training in minimalistic footwear. The majority of the participants continued to use an RFS pattern after training in minimalistic footwear, and these participants experienced higher vertical loading rates. Continued exposure to these greater loading rates may have detrimental effects over time., (Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.)

Summer dance intensive programs are an integral part of many serious dancers' training. The risk and rate of injury in this setting have not been well studied. The goal of this data analysis is to detail the epidemiology of dance injuries reported during a summer dance intensive over a consecutive 3 year period. Data collection included information regarding the number of evaluation and treatment sessions conducted at the program's walk-in clinic, body regions injured, whether the injuries were recurrences of pre-existing conditions or newly sustained during the intensive, and at what point in the program they were recorded. Overall, more of the clinic's clientele presented with multiple injuries than with single discrete injuries. The anatomic distribution of injuries appears to be consistent with previously reported data, with the four most commonly injured body regions being ankle, pelvis and hip, knee, and lumbar spine. Injuries sustained during the intensive (IR) occurred at a 2:1 ratio to pre-intensive injuries (PR). Relative to those with PR injuries, dancers with IR injuries were far more likely to present during the first half of the program. This study is a first step toward filling a gap in the literature by describing injury incidence in a specific population within the dance community.

Purpose/background: Dynamic balance is an important component of motor skill development. Poor dynamic balance has previously been associated with sport related injury. However, the vast majority of dynamic balance studies as they relate to sport injury have occurred in developed North American or European countries. Thus, the purpose of this study was to compare dynamic balance in adolescent male soccer players from Rwanda to a matched group from the United States., Methods: Twenty-six adolescent male soccer players from Rwanda and 26 age- and gender-matched control subjects from the United States were screened using the Lower Quarter Y Balance Test during their pre-participation physical. Reach asymmetry (cm) between limbs was examined for all reach directions. In addition, reach distance in each direction (normalized to limb length, %LL) and the composite reach score (also normalized to %LL) were examined. Dependent samples t-tests were performed with significant differences identified at p<0.05., Results: Twenty-six male soccer players from Rwanda (R) were matched to twenty-six male soccer players from the United States (US). The Rwandan soccer players performed better in the anterior (R: 83.9 ± 3.2 %LL; US: 76.5 ± 6.6 %LL, p<0.01), posterolateral (R: 114.4 ± 8.3 %LL ; US: 106.5 ± 8.2 %LL, p<0.01) and composite (R: 105.6 ± 1.3 %LL; US: 97.8 ± 6.2 %LL, p<0.01) reach scores. No significant differences between groups were observed for reach asymmetry., Conclusions: Adolescent soccer players from Rwanda exhibit superior performance on a standardized dynamic balance test as comparison to similar athletes from the United States. The examination of movement abilities of athletes from countries of various origins may allow for a greater understanding of the range of true normative values for dynamic balance., Levels of Evidence: 3b.

Multiple surgical approaches exist for total hip arthroplasty (THA). Each approach has risks and benefits in regard to complications and changes in postoperative gait. This study examined the effect of three surgical approaches on postoperative gait mechanics. Thirty patients completed a self-selected speed level walking gait assessment preoperatively, 6 weeks, and 1 year after surgery. We found no difference between approaches 1 year following surgery for any study variable. Several differences existed between time points independent of surgical approach. Significant improvement was found in sagittal and frontal plane hip ROM, peak hip extension and adduction angle and moment, the functional measures, walking speed, and the Harris Hip Score. This study suggests that postoperative gait changes are similar for the three analyzed surgical approaches., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Archosauria and their closest relatives, the non-archosaurian archosauriforms, diversified in the Early and Middle Triassic, soon after the end-Permian extinction. This diversification is poorly documented in most Lower and Middle Triassic rock sequences because fossils of early groups of archosauriforms are relatively rare compared to those of other amniotes. The early Middle Triassic (? late Anisian) Manda beds of southwestern Tanzania form an exception, with early archosaur skeletons being relatively common and preserved as articulated or associated specimens. The Manda archosaur assemblage is exceptionally diverse for the Middle Triassic. However, to date, no non-archosaurian archosauriforms have been reported from these rocks., Methodology/principal Findings: Here, we name a new taxon, Asperoris mnyama gen. et sp. nov., from the Manda beds and thoroughly describe the only known specimen. The specimen consists of a well-preserved partial skull including tooth-bearing elements (premaxilla, maxilla), the nasal, partial skull roof, and several incomplete elements. All skull elements are covered in an autapomorphic highly rugose sculpturing. A unique combination of character states indicates that A. mnyama lies just outside Archosauria as a stem archosaur within Archosauriformes, but more precise relationships of A. mnyama relative to other early archosauriform clades (e.g., Erythrosuchidae) cannot be determined currently., Conclusions/significance: Asperoris mnyama is the first confirmed non-archosaurian archosauriform from the Manda beds and increases the morphological and taxonomic diversity of early archosauriforms known from the Middle Triassic. The direct association of A. mnyama with species referable to Archosauria demonstrates that non-archosaurian archosauriforms were present during the rise and early diversification of Archosauria. Non-archosaurian archosauriforms and archosaurs co-occur in fossil reptile assemblages across Pangaea from the late Early Triassic to the end of the Late Triassic.

Weight shift during the golf swing has been a topic of discussion among golf professionals; however, it is still unclear how weight shift varies in golfers of different performance levels. The main purpose of this study was to examine the following: (a) the changes in the peak ground reaction forces (GRF) and the timing of these events between high (HHCP) and low handicap (LHCP) golfers and (b) the differences between the leading and trailing legs. Twenty-eight male golfers were recruited and divided based on having an LHCP < 9 or HHCP > 9. Three-dimensional GRF peaks and the timing of the peaks were recorded bilaterally during a golf swing. The golf swing was divided into different phases: (a) address to the top of the backswing, (b) top of the backswing to ball contact, and (c) ball contact to the end of follow through. Repeated measures analyses of variance (α = 0.05) were completed for each study variable: the magnitude and the timing of peak vertical GRF, peak lateral GRF, and peak medial GRF (α = 0.05). The LHCP group had a greater transfer of vertical force from the trailing foot to the leading foot in phase 2 than the HHCP group. The LHCP group also demonstrated earlier timing of peak vertical force throughout the golf swing than the HHCP group. The LHCP and HHCP groups demonstrated different magnitudes of peak lateral force. The LHCP group had an earlier timing of peak lateral GRF in phase 2 and earlier timing of peak medial GRF in phases 1 and 2 than the HHCP group. In general, LHCP golfers demonstrated greater and earlier force generation than HHCP golfers. It may be relevant to consider both the magnitude of the forces and the timing of these events during golf-specific training to improve performance. These data reveal weight shifting differences that can be addressed by teaching professionals to help their students better understand weight transfer during the golf swing to optimize performance.

Background: Field expedient screening tools that can identify individuals at an elevated risk for injury are needed to minimize time loss in American football players. Previous research has suggested that poor dynamic balance may be associated with an elevated risk for injury in athletes; however, this has yet to be examined in college football players., Hypothesis: To determine if dynamic balance deficits are associated with an elevated risk of injury in collegiate football players. It was hypothesized that football players with lower performance and increased asymmetry in dynamic balance would be at an elevated risk for sustaining a noncontact lower extremity injury., Study Design: Prospective cohort study., Methods: Fifty-nine collegiate American football players volunteered for this study. Demographic information, injury history, and dynamic balance testing performance were collected, and noncontact lower extremity injuries were recorded over the course of the season. Receiver operator characteristic curves were calculated based on performance on the Star Excursion Balance Test (SEBT), including composite score and asymmetry, to determine the population-specific risk cut-off point. Relative risk was then calculated based on these variables, as well as previous injury., Results: A cut-off point of 89.6% composite score on the SEBT optimized the sensitivity (100%) and specificity (71.7%). A college football player who scored below 89.6% was 3.5 times more likely to get injured., Conclusion: Poor performance on the SEBT may be related to an increased risk for sustaining a noncontact lower extremity injury over the course of a competitive American football season., Clinical Relevance: College football players should be screened preseason using the SEBT to identify those at an elevated risk for injury based upon dynamic balance performance to implement injury mitigation strategies to this specific subgroup of athletes.

Context: Metatarsal stress fractures are common in cleated-sport athletes. Previous authors have shown that plantar loading varies with footwear, sex, and the athletic task., Objective: To examine the effects of shoe type and sex on plantar loading in the medial midfoot (MMF), lateral midfoot (LMF), medial forefoot (MFF), middle forefoot (MidFF), and lateral forefoot (LFF) during a jump-landing task., Design: Crossover study., Setting: Laboratory., Patients or Other Participants: Twenty-seven recreational athletes (14 men, 13 women) with no history of lower extremity injury in the last 6 months and no history of foot or ankle surgery., Main Outcome Measure(s): The athletes completed 7 jumping trials while wearing bladed-cleat, turf-cleat, and running shoes. Maximum force, contact area, contact time, and the force-time integral were analyzed in each foot region. We calculated 2 × 3 analyses of variance (α = .05) to identify shoe-condition and sex differences., Results: We found no shoe × sex interactions, but the MMF, LMF, MFF, and LFF force-time integrals were greater in men (P < .03). The MMF maximum force was less with the bladed-cleat shoes (P = .02). Total foot and MidFF maximum force was less with the running shoes (P < .01). The MFF and LFF maximum forces were different among all shoe conditions (P < .01). Total foot contact area was less in the bladed-cleat shoes (P = .01). The MMF contact area was greatest in the running shoes (P < .01). The LFF contact area was less in the running shoes (P = .03). The MFF and LFF force-time integrals were greater with the bladed-cleat shoes (P < .01). The MidFF force-time integral was less in the running shoes (P < .01)., Conclusions: Independent of shoe, men and women loaded the foot differently during a jump landing. The bladed cleat increased forefoot loading, which may increase the risk for forefoot injury. The type of shoe should be considered when choosing footwear for athletes returning to activity after metatarsal stress fractures.

In athletics, efficient screening tools are sought to curb the rising number of noncontact injuries and associated health care costs. The authors hypothesized that an injury prediction algorithm that incorporates movement screening performance, demographic information, and injury history can accurately categorize risk of noncontact lower extremity (LE) injury. One hundred eighty-three collegiate athletes were screened during the preseason. The test scores and demographic information were entered into an injury prediction algorithm that weighted the evidence-based risk factors. Athletes were then prospectively followed for noncontact LE injury. Subsequent analysis collapsed the groupings into two risk categories: Low (normal and slight) and High (moderate and substantial). Using these groups and noncontact LE injuries, relative risk (RR), sensitivity, specificity, and likelihood ratios were calculated. Forty-two subjects sustained a noncontact LE injury over the course of the study. Athletes identified as High Risk (n = 63) were at a greater risk of noncontact LE injury (27/63) during the season [RR: 3.4 95% confidence interval 2.0 to 6.0]. These results suggest that an injury prediction algorithm composed of performance on efficient, low-cost, field-ready tests can help identify individuals at elevated risk of noncontact LE injury., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The use of lateral foot wedging in the management of medial knee osteoarthritis is under scrutiny. Interestingly, there have been minimal efforts to evaluate biomechanical effectiveness with long-term use. Therefore, we aimed to evaluate dynamic knee loading (assessed using the knee adduction moment) and other secondary gait parameters in patients with medial knee osteoarthritis wearing lateral foot wedging at a baseline visit and after 1 year of wear. Three-dimensional gait data were captured in an intervention group of 19 patients with symptomatic medial knee osteoarthritis wearing their prescribed laterally wedged foot orthoses at 0 and 12 months. Wedge amounts were prescribed based on symptom response to a step-down test. A control group of 19 patients wearing prescribed neutral orthoses were also captured at 0 and 12 months. The gait of the intervention group wearing neutral orthoses was additionally captured. Walking speed and shoes were controlled. Analyses of variance were conducted to examine for group-by-time (between the groups in their prescribed orthoses) and condition-by-time (within the intervention group) interactions, main effects, and simple effects. We observed increased knee adduction moments and frontal plane motion over time in the control group but not the intervention group. Further, within the intervention group, the mechanical effectiveness of the lateral wedging did not decrease. In patients with medial knee osteoarthritis, the effects of lateral foot wedging on pathomechanics associated with medial knee osteoarthritis were favorable and sustained over time., (Copyright © 2012 Orthopaedic Research Society.)

Unlabelled: PURPOSEBACKGROUND: Quadriceps function is an important outcome following lower extremity injury and surgery. Measurements of quadriceps function are particularly helpful initially post surgery, however traditional quadriceps strength measures like isokinetic testing are contraindicated during this time period. Inclusion of dynamic musculoskeletal ultrasound imaging in the clinical setting has been beneficial in understanding quadriceps activation specifically rectus femoris (RF) contraction; however, there is a paucity of literature in this area. The purpose of the current study was to describe the cross-sectional area (CSA) of the RF across varying knee flexion angles., Methods: Forty-five adult recreational athletes were recruited for the study (21 males, 24 females). All subjects underwent tests of maximal volitional isometric contractions of the knee extensors at 0, 30, 60 and 90 degrees of knee flexion. During the trials, musculoskeletal ultrasound images of the RF at 15 cm from the superior pole of the patella were taken at rest and during contraction for each of the angular positions. Mixed model ANOVAs (angle x sex) were utilized to examine the differences between males and females for different angular positions. These analyses were conducted for the resting CSA, active CSA, and the contractile index (resting - active)., Results: RF cross-sectional area increased with increasing angles of knee flexion for both the resting and active conditions. The contractile index consistently decreased as knee flexion angle increased. No statistically significant interactions or main effects for sex were observed, although differences were observed in the trajectories of the data sets for males and females., Conclusions: RF CSA is dependent on knee flexion angle in both males and females. As a result, the assessment of RF CSA should be conducted in a standardized position if this variable is to be utilized as a meaningful measure of muscle size during rehabilitation. Additional research should seek out which factors are associated with clinically relevant factors that effect RF CSA across the range of knee flexion., Level of Evidence: 3b.

Pseudosuchia, one of the two main clades of Archosauria (Reptilia: Diapsida), suffered a major decline in lineage diversity during the Triassic-Jurassic (TJ) mass extinction (approx. 201 Ma). Crocodylomorpha, including living crocodilians and their extinct relatives, is the only group of pseudosuchians that survived into the Jurassic. We reassess changes in pseudosuchian morphological diversity (disparity) across this time interval, using considerably larger sample sizes than in previous analyses. Our results show that metrics of pseudosuchian disparity did not change significantly across the TJ boundary, contrasting with previous work suggesting low pseudosuchian disparity in the Early Jurassic following the TJ mass extinction. However, a significant shift in morphospace occupation between Late Triassic and Early Jurassic taxa is recognized, suggesting that the TJ extinction of many pseudosuchian lineages was followed by a major and geologically rapid adaptive radiation of crocodylomorphs. This marks the onset of the spectacularly successful evolutionary history of crocodylomorphs in Jurassic and Cretaceous ecosystems.

Background: Malalignment and dysfunction of the foot have been associated with an increased propensity for overuse and traumatic injury in athletes. Several multisegment foot models have been developed to investigate motions in the foot. However, it remains unknown whether the kinematics measured by different multisegment foot models are equivocal. The purpose of the present study is to examine the efficacy of two multisegment foot models in tracking aberrant foot function., Methods: Ten high-arched and ten low-arched female athletes walked and ran while ground reaction forces and three-dimensional kinematics were tracked using the Leardini and Oxford multisegment foot models. Ground reaction forces and joint angles were calculated with Visual 3D (C-Motion Inc, Germantown, MD). Repeated-measures analyses of variance were used to analyze peak eversion, time to peak eversion, and eversion excursions., Results: The Leardini model was more sensitive to differences in peak eversion angles than the Oxford model. However, the Oxford model detected differences in eversion excursion values that the Leardini model did not detect., Conclusions: Although both models found differences in frontal plane motion between high- and low-arched athletes, the Leardini multisegment foot model is suggested to be more appropriate as it directly tracks frontal plane midfoot motion during dynamic motion.

Infection with human rhinovirus (HRV) is thought to result in acute respiratory exacerbations of chronic obstructive pulmonary disorder (COPD). Consequently, prevention of HRV infection may provide therapeutic benefit to these patients. As all major group HRV serotypes infect cells via an interaction between viral coat proteins and intercellular adhesion molecule-1 (ICAM-1), it is likely that inhibitors of this interaction would prevent or reduce infections. Our objective was to use phage display technology in conjunction with naive human antibody libraries to identify anti-ICAM-1 antibodies capable of functional blockade of HRV infection. Key to success was the development of a robust, functionally relevant high-throughput screen (HTS) compatible with the specific challenges of antibody screening. In this article, we describe the development of a novel homogeneous time-resolved fluorescence (HTRF) assay based on the inhibition of soluble ICAM-1 binding to live HRV16. We describe the implementation of the method in an antibody screening campaign and demonstrate the biological relevance of the assay by confirming the activity of resultant antibodies in a cell-based in vitro HRV infection assay.

Objective: To examine whether measures of physiologic function and fundamental movement are predictive of injury in firefighters during a training academy., Participants: 108 firefighter trainees enrolled in the training academy., Methods: Baseline measures of physical performance and fundamental movement patterns were obtained in firefighters entering a training academy to determine predictors of injury. The physical performance measures were standardized tests of individual maximum performance on a set of four different total body tests and one firefighter specific performance test, the tower test. Measurements of fundamental movement patterns consisted of the seven tests of the Functional Movement Screen (FMS) along with the composite score.Performance on each of the individual tests was examined to determine if any of the variables were predictive of injury., Results: ROC curve analysis established that a FMS cut score of ≤ 14 was able to discriminate between those at a greater risk for injury. In addition, the deep squat and push up component of the FMS were statistically significant predictors of injury status along with the sit and reach test., Conclusions: Injury in firefighters during academy can be predicted by baseline measures of musculoskeletal movement and physiology.

Objective: Men and women exhibit different movement patterns, which are thought to contribute to the increased incidence of anterior cruciate ligament injuries in females. Although gender differences have been observed in movement, few studies have examined gender differences during different types of landings., Design: Prospective gender comparison study., Setting: Controlled laboratory study., Patients: Fourteen male and 14 female recreational soccer players were recruited for the study. All subjects performed a soccer-specific jump heading activity to examine differences in landing mechanics before and after heading the soccer ball. Subjects began the task by performing a forward jump onto 2 force platforms (landing 1) and conducting a countermovement before jumping up to head a soccer ball that was hanging above the force platform before, then landing back on the force platforms (landing 2)., Main Outcome Measures: A 2-way analysis of variance (gender × landing) was performed to examine the interaction between gender and different types of landings on sagittal plane joint mechanics., Results: Significant interactions existed for the peak hip extension moment and vertical ground reaction force where the male players exhibited increased values during the second landing compared with the female players. Males exhibited greater peak plantarflexion and knee extension moments, but decreased peak hip flexion. Main effects for landing exhibited lower kinematic and larger kinetic values except for the peak plantarflexion moment., Conclusions: Female and male players appear to land differently depending on the type of landing. Therefore, specificity of landing type may be important to consider when screening for injury risk factors., Clinical Relevance: This study examines the differences between genders during 2 different landing tasks and demonstrates the importance of considering the jumping task when screening individuals for injury risk factors.

Background: Patellofemoral pain is one of the most common lower extremity overuse injuries in runners and is significantly more common in females. This study evaluated differences in the timing and magnitude of gluteal muscle activity as well as hip and knee joint frontal and transverse plane kinematics between male and female runners in the context of this gender bias., Methods: Twenty healthy male and 20 healthy female runners were participants. Three-dimensional lower extremity kinematics, and gluteus medius and gluteus maximus muscle activation were recorded using motion analysis and electromyography as subjects ran at 3.7 m/s (+/-5%). Comparisons of hip and knee joint kinematic and gluteus muscle activation data were made using independent t-tests (α=0.05)., Findings: Females ran with 40% greater peak gluteus maximus activation level (P=0.028, effect size=0.79) and 53% greater average activation level (P=0.013, effect size=0.93) than males. Female runners also displayed greater hip adduction (P=.001, effect size=1.20) and knee abduction (P=0.011, effect size=0.87) angles at initial contact, greater hip adduction at peak vertical ground reaction force (P<0.001, effect size=1.31), and less knee internal rotation excursion than males (P=0.035, effect size=0.71)., Interpretation: Greater gluteus maximus activation levels during running may predispose females to earlier gluteus maximus fatigue, promoting altered lower extremity running kinematics thought to be associated with the etiology of patellofemoral pain. Gender differences in transverse and frontal plane hip and knee kinematics observed in this study may also contribute to the gender bias for patellofemoral pain among females., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: Anterior cruciate ligament (ACL) reinjury rates are high in adolescent patients. Knee braces are commonly used after ACL reconstruction to prevent reinjury during return to sports., Hypothesis: Adolescent patients following ACL injury would demonstrate a decreased vertical ground-reaction force, knee extension moment, knee flexion angle, and knee flexion velocity on the surgical limb when compared with the nonsurgical limb during a side-cutting task. A functional knee extension-resistant brace would decrease the limb asymmetries., Study Design: Controlled laboratory study., Methods: Twenty-three adolescent patients 6 months after ACL reconstruction were recruited for this study. Three-dimensional kinematic and kinetic data were collected bilaterally (surgical, nonsurgical) during a 35° side-cutting task while the patient was wearing and not wearing a functional knee extension-resistant brace (nonbraced, braced) on the surgical limb., Results: The surgical limb demonstrated a significant decrease in peak impact vertical ground-reaction force (2.55 body weight [BW] vs 2.8 BW; P < .01), peak propulsion vertical ground-reaction force (2.15 BW vs 2.3 BW; P < .01), peak knee extension moment (0.13 BW × body height [BH] vs 0.17 BW × BH; P < .01), knee flexion angle at peak knee flexion velocity (27.8° vs 30.0°; P = .01), peak knee flexion angle (44.1° vs 48.5°; P < .01), and peak knee flexion velocity (571.3 deg/sec vs 640.1 deg/sec; P < .01) when compared with the nonsurgical limb during both nonbraced and braced conditions. Bracing increased the initial knee flexion velocity (42.4 deg/sec vs -40.2 deg/sec; P = .01) and decreased the initial knee flexion angle on the surgical limb (13.1° vs 15.7°; P < .01). Bracing also affected kinematics of the nonsurgical limb. Bracing did not decrease the asymmetry between surgical and nonsurgical limbs., Conclusion: Adolescent patients 6 months after ACL reconstruction demonstrated significant kinematic and kinetic asymmetries between the surgical and nonsurgical limbs. The limb asymmetries persisted when the patients were wearing a functional knee brace. There were changes in the surgical knee kinematics with and without bracing, especially near initial ground contact., Clinical Relevance: The limb asymmetries are of concern with regard to injuring the graft or the contralateral limb when the patients return to sport.

The inclusion of movement tests before performance training and sport participation is gaining popularity as part of musculoskeletal screening for injury. The identification of an athlete's asymmetries and poor performance in the preseason allows coaches and sports medicine clinicians the opportunity to proactively address these deficits to reduce the potential for injury. Currently, there are no tests reported in the literature that simultaneously require shoulder and core stability while taking the subjects through a large range of motion at the end range of their stability. Thus, the purpose of this article was to describe the Upper Quarter Y Balance Test and report the gender differences in the performance of the test. Upper extremity reach distances were measured in 95 active adults using a standardized upper extremity balance-and-reach protocol. Intraclass correlation coefficients were used to assess reliability, and gender differences were analyzed using an independent samples t-test, whereas bilateral differences were analyzed using a dependent samples t-test for the normalized composite reach scores. Intraclass correlation coefficient (3.1) for test-retest reliability ranged from 0.80 to 0.99. Intraclass correlation coefficient (3.1) for interrater reliability was 1.00. Average composite scores (right/left) reported as a percentage of limb length were 81.7/82.3% for men and 80.7/80.7% for women. The results of the study suggest that the Upper Quarter Y Balance Test is a reliable test for measuring upper extremity reach distance while in a closed-chain position. It was further determined that there was no significant difference in performance between genders or between sides on the test when normalized to limb length. Coaches and sports medicine professionals may consider incorporating the Upper Quarter Y Balance Test as part of their preprogram testing to identify movement limitations and asymmetries in athletes and thereby may reduce injury.

Background: Ankle osteoarthritis has been associated with trauma, instability, and inflammatory arthritis. Limited literature exists examining the effect of body weight on ankle joint loading. The purpose of this study was to examine the relationship between increased weight and gender on ankle kinematics and kinetics., Methods: Fifty-three (28 male, 25 female) subjects were recruited for the study. All subjects underwent a standard level walking gait analysis in four different weight conditions (normal, 10%, 15%, and 20% increased body weight). Testing order was randomized. A series of mixed-factor, repeated-measures analyses of variance (weight by gender) were used to determine statistical differences between the groups (p < .05)., Results: Walking speed was not significantly different between gender or weight conditions. No significant differences existed for step length, step time, stride length, swing time, or sagittal plane ankle kinematics and kinetics. A significant increase in plantarflexion moment existed for the males (p < .05). The peak plantarflexion moment increased as weight increased. Single support time (p = .042) was significantly different between the no weight and the 15% and 20% increased weight conditions. In addition, double support time was significantly longer in the males compared with females (p < .001) and significantly increased for each weight condition (p < .001)., Conclusion: Increasing weight alters spatial temporal mechanics and sagittal plane ankle kinetics in a healthy control population. The effect of increasing weight appears to be similar between genders., Clinical Relevance: The findings of the present study may be relevant for future studies to assess the role of weight as a potential covariate on postoperative outcomes and gait mechanics.

Context: Balance ability has been associated with performance and injury prevention in athletes. Few published reports have investigated the differences in dynamic balance abilities among male high school, collegiate, and professional soccer players., Objective: To examine the differences on the Lower Quarter Y-Balance Test in male high school, collegiate, and professional soccer players., Design: Descriptive laboratory study., Setting: Field testing. Patients or Other Participants: Dynamic balance data were collected for male high school (HS; n = 38), collegiate (n = 37), and professional (n = 44) soccer players during preparticipation physical examinations using the Lower Quarter Y Balance Test standardized protocol. Main Outcome Measure(s): For the Lower Quarter Y Balance Test, the participant reaches with 1 foot in the anterior, posteromedial, and posterolateral directions while standing on a centralized stance platform with the other foot. The test is performed for both left and right limbs. Differences in reach distances between competition levels were analyzed using a 1-way analysis of variance with significance set at P < .05. The HS group had a greater anterior reach distance than the other 2 groups. In contrast, the HS group had less reach distance in the posteromedial and posterolateral directions than the other groups. Also, HS players tended to exhibit a lower composite reach score than the other groups, but this difference was not significant (P = .08). No differences were observed among groups for bilateral symmetry in any of the reach directions., Conclusions: Dynamic balance performance varied with competition level. This may indicate that athletes' movement strategies may be different depending on the competition level and that normative values may need to be established for each competition level.

Abiotic and biological factors have been hypothesized as controlling maximum body size of tetrapods and other animals through geological time. We analyse the effects of three abiotic factors--oxygen, temperature and land area--on maximum size of Permian-Jurassic archosauromorphs and therapsids, and Cenozoic mammals, using time series generalized least-squares regression models. We also examine maximum size growth curves for the Permian-Jurassic data by comparing fits of Gompertz and logistic models. When serial correlation is removed, we find no robust correlations, indicating that these environmental factors did not consistently control tetrapod maximum size. Gompertz models--i.e. exponentially decreasing rate of size increase at larger sizes--fit maximum size curves far better than logistic models. This suggests that biological limits such as reduced fecundity and niche space availability become increasingly limiting as larger sizes are reached. Environmental factors analysed may still have imposed an upper limit on tetrapod body size, but any environmentally imposed limit did not vary substantially during the intervals examined despite variation in these environmental factors.

Background: Total ankle replacement (TAR) continues to grow as an alternative to arthrodesis for patients who suffer from end-stage ankle arthritis. The purpose of this study was to examine changes in gait mechanics from before surgery to 1 and 2 years after surgery in patients who received a fixed-bearing TAR., Methods: Fifty-one patients with a primary fixed-bearing TAR and no complications requiring further surgery were identified from a database and enrolled in this non-randomized study. Subjects were examined preoperatively, and at 1 and 2 years postoperatively. Three-dimensional joint mechanics and ground reaction forces (GRF) were collected during level walking. The Four Square Step Test, Timed Up and Go (TUG), VAS, and the AOFAS-Hindfoot score were assessed for each subject at each time point., Results: TUG, VAS and AOFAS-Hindfoot score along with all measured kinetic parameters demonstrated significant improvements across all of the time points (p < 0.05). Four Square Step Test time was significantly improved between the preoperative and 2-year postoperative time point (p < 0.05). Measured ankle dorsiflexion angles did not demonstrate significant change between any time points., Conclusions: All of the observed changes suggest improved or maintained functioning in patients who received a TAR with the greatest improvement occurring within the first year. Sagittal plane ankle range of motion and dorsiflexion angle at heel strike were unchanged across all of the time points. The results of this study indicate that patients with end-stage osteoarthritis demonstrate improvements in pain and gait up to 2 years following surgery while maintaining ankle range of motion.

Musculoskeletal injuries are a primary source of disability in the U.S. Military. Physical training and sports-related activities account for up to 90% of all injuries, and 80% of these injuries are considered overuse in nature. As a result, there is a need to develop an evidence-based musculoskeletal screen that can assist with injury prevention. The purpose of this study was to assess the capability of an automated system to improve the efficiency of field expedient tests that may help predict injury risk and provide corrective strategies for deficits identified. The field expedient tests include survey questions and measures of movement quality, balance, trunk stability, power, mobility, and foot structure and mobility. Data entry for these tests was automated using handheld computers, barcode scanning, and netbook computers. An automated algorithm for injury risk stratification and mitigation techniques was run on a server computer. Without automation support, subjects were assessed in 84.5 ± 9.1 minutes per subject compared with 66.8 ± 6.1 minutes per subject with automation and 47.1 ± 5.2 minutes per subject with automation and process improvement measures (p < 0.001). The average time to manually enter the data was 22.2 ± 7.4 minutes per subject. An additional 11.5 ± 2.5 minutes per subject was required to manually assign an intervention strategy. Automation of this injury prevention screening protocol using handheld devices and netbook computers allowed for real-time data entry and enhanced the efficiency of injury screening, risk stratification, and prescription of a risk mitigation strategy.

A major macroevolutionary question concerns how long-term patterns of body-size evolution are underpinned by smaller scale processes along lineages. One outstanding long-term transition is the replacement of basal therapsids (stem-group mammals) by archosauromorphs, including dinosaurs, as the dominant large-bodied terrestrial fauna during the Triassic (approx. 252-201 million years ago). This landmark event preceded more than 150 million years of archosauromorph dominance. We analyse a new body-size dataset of more than 400 therapsid and archosauromorph species spanning the Late Permian-Middle Jurassic. Maximum-likelihood analyses indicate that Cope's rule (an active within-lineage trend of body-size increase) is extremely rare, despite conspicuous patterns of body-size turnover, and contrary to proposals that Cope's rule is central to vertebrate evolution. Instead, passive processes predominate in taxonomically and ecomorphologically more inclusive clades, with stasis common in less inclusive clades. Body-size limits are clade-dependent, suggesting intrinsic, biological factors are more important than the external environment. This clade-dependence is exemplified by maximum size of Middle-early Late Triassic archosauromorph predators exceeding that of contemporary herbivores, breaking a widely-accepted 'rule' that herbivore maximum size greatly exceeds carnivore maximum size. Archosauromorph and dinosaur dominance occurred via opportunistic replacement of therapsids following extinction, but were facilitated by higher archosauromorph growth rates.

Lumbar musculature plays an important role in stabilization during functional movements such as walking, bending and overhead activities. Current research has focused on the lumbar multifidus (LM) muscle to determine if altered activity of the LM may contribute to low back pain (LBP). Therefore, the purpose of this study was to determine whether experimentally induced LBP affects deep LM muscle activity during functionally oriented tasks, weight shifting and upper extremity lifting. Intramuscular electromyography (EMG) activity of the LM at L4 was measured in 17 healthy adults during a dominant side shoulder flexion and extension task and during a staggered-stance weight shift task. Data were collected at baseline, after pain was induced with hypertonic saline and after the pain had subsided. Comparisons of within-subjects effects were performed with the use of a two-way repeated-measure ANOVA. A significantly higher magnitude of activity was found in the induced pain condition as compared to the baseline condition for the shoulder extension phase of the upper extremity task (p = 0.04). During forward weight shifting, lower values in both the induced pain (p = 0.02) and the recovery conditions (p = 0.01) were measured. During backward weight shifting, lower values were measured during the recovery condition as compared to baseline (p = 0.03). Across trials and subjects the EMG amplitudes were increased during the extension phase of the upper extremity task and decreased during the weight shifting task. These results suggest that the LM does not respond to induced pain in the same manner during different phases of functionally oriented tasks., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Disparity, or morphological diversity, is often quantified by evolutionary biologists investigating the macroevolutionary history of clades over geological timescales. Disparity is typically quantified using proxies for morphology, such as measurements, discrete anatomical characters, or geometric morphometrics. If different proxies produce differing results, then the accurate quantification of disparity in deep time may be problematic. However, despite this, few studies have attempted to examine disparity of a single clade using multiple morphological proxies. Here, as a case study for this question, we examine the disparity of the volant Mesozoic fossil reptile clade Pterosauria, an intensively studied group that achieved substantial morphological, ecological and taxonomic diversity during their 145+ million-year evolutionary history. We characterize broadscale patterns of cranial morphological disparity for pterosaurs for the first time using landmark-based geometric morphometrics and make comparisons to calculations of pterosaur disparity based on alternative metrics. Landmark-based disparity calculations suggest that monofenestratan pterosaurs were more diverse cranially than basal non-monofenestratan pterosaurs (at least when the aberrant anurognathids are excluded), and that peak cranial disparity may have occurred in the Early Cretaceous, relatively late in pterosaur evolution. Significantly, our cranial disparity results are broadly congruent with those based on whole skeleton discrete character and limb proportion data sets, indicating that these divergent approaches document a consistent pattern of pterosaur morphological evolution. Therefore, pterosaurs provide an exemplar case demonstrating that different proxies for morphological form can converge on the same disparity signal, which is encouraging because often only one such proxy is available for extinct clades represented by fossils. Furthermore, mapping phylogeny into cranial morphospace demonstrates that pterosaur cranial morphology is significantly correlated with, and potentially constrained by, phylogenetic relationships., (© 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.)

The extinction of non-avian dinosaurs 65 million years ago is a perpetual topic of fascination, and lasting debate has focused on whether dinosaur biodiversity was in decline before end-Cretaceous volcanism and bolide impact. Here we calculate the morphological disparity (anatomical variability) exhibited by seven major dinosaur subgroups during the latest Cretaceous, at both global and regional scales. Our results demonstrate both geographic and clade-specific heterogeneity. Large-bodied bulk-feeding herbivores (ceratopsids and hadrosauroids) and some North American taxa declined in disparity during the final two stages of the Cretaceous, whereas carnivorous dinosaurs, mid-sized herbivores, and some Asian taxa did not. Late Cretaceous dinosaur evolution, therefore, was complex: there was no universal biodiversity trend and the intensively studied North American record may reveal primarily local patterns. At least some dinosaur groups, however, did endure long-term declines in morphological variability before their extinction.

Purpose/background: Researchers have previously reported on the importance of dynamic balance in assessing an individual's risk for injury during sport. However, to date there is no research on whether multiple sport participation affects dynamic balance ability. Therefore, the purpose of this study was to determine if there was a difference in dynamic balance scores in high school athletes that competed in one sport only as compared athletes who competed in multiple sports, as tested by the Lower Quarter Y Balance Test (YBT-LQ)., Methods: Ninety-two high school athletes who participated in one sport were matched, by age, gender and sport played, to athletes who participated in the same sport as well as additional sports. All individuals were assessed using the YBT-LQ to examine differences in composite reach score and reach direction asymmetry between single sport and multiple sport athletes. The greatest reach distance of three trials in each reach direction for right and left lower-extremities was normalized by limb length and used for analysis. A two-way ANOVA (gender x number of sports played) was used to statistically analyze the variables in the study., Results: No significant interactions or main effects related to number of sports played were observed for any YBT-LQ score (p>0.05). Male athletes exhibited significantly greater normalized reach values for the posteromedial, posterolateral, and composite reach while also exhibiting a larger anterior reach difference when compared to the females. Athletes who participated in multiple sports had similar performances on the YBT-LQ when compared to athletes who participated in a single sport., Conclusions: The findings of this study suggest that the number of sports played by a high school athlete does not need to be controlled for when evaluating dynamic balance with the YBT-LQ.

Pneumatic (air-filled) postcranial bones are unique to birds among extant tetrapods. Unambiguous skeletal correlates of postcranial pneumaticity first appeared in the Late Triassic (approximately 210 million years ago), when they evolved independently in several groups of bird-line archosaurs (ornithodirans). These include the theropod dinosaurs (of which birds are extant representatives), the pterosaurs, and sauropodomorph dinosaurs. Postulated functions of skeletal pneumatisation include weight reduction in large-bodied or flying taxa, and density reduction resulting in energetic savings during foraging and locomotion. However, the influence of these hypotheses on the early evolution of pneumaticity has not been studied in detail previously. We review recent work on the significance of pneumaticity for understanding the biology of extinct ornithodirans, and present detailed new data on the proportion of the skeleton that was pneumatised in 131 non-avian theropods and Archaeopteryx. This includes all taxa known from significant postcranial remains. Pneumaticity of the cervical and anterior dorsal vertebrae occurred early in theropod evolution. This 'common pattern' was conserved on the line leading to birds, and is likely present in Archaeopteryx. Increases in skeletal pneumaticity occurred independently in as many as 12 lineages, highlighting a remarkably high number of parallel acquisitions of a bird-like feature among non-avian theropods. Using a quantitative comparative framework, we show that evolutionary increases in skeletal pneumaticity are significantly concentrated in lineages with large body size, suggesting that mass reduction in response to gravitational constraints at large body sizes influenced the early evolution of pneumaticity. However, the body size threshold for extensive pneumatisation is lower in theropod lineages more closely related to birds (maniraptorans). Thus, relaxation of the relationship between body size and pneumatisation preceded the origin of birds and cannot be explained as an adaptation for flight. We hypothesise that skeletal density modulation in small, non-volant, maniraptorans resulted in energetic savings as part of a multi-system response to increased metabolic demands. Acquisition of extensive postcranial pneumaticity in small-bodied maniraptorans may indicate avian-like high-performance endothermy., (© 2011 The Authors. Biological Reviews © 2011 Cambridge Philosophical Society.)

We describe how a modified Gini index serves as an improved method of estimating health care disparities. The method, although general, is applied to an example of birth weight disparities and to their effect on subsequent mortality. The method provides the between-group results obtainable from current methods (i.e. how Hispanics generally fare relative to non-Hispanic Whites) but adds measures of within-group disparities (i.e. which specific Hispanics experience the greatest disparate treatment). Our application to birth weights and receipt of prenatal care, which may provide an upper bound because of omitted variables, shows that the time-of-birth disparities are associated with increased infant mortality within the first year of life., (Copyright © 2010 John Wiley & Sons, Ltd.)

Background: Heterodontosaurids are an important but enigmatic and poorly understood early radiation of ornithischian dinosaurs. The late-surviving heterodontosaurid Fruitadens haagarorum from the Late Jurassic (early Tithonian) Morrison Formation of the western USA is represented by remains of several small (<1 metre total body length, <1 kg body mass) individuals that include well-preserved but incomplete cranial and postcranial material. Fruitadens is hypothesized to represent one of the smallest known ornithischian dinosaurs., Methodology/principal Findings: We describe the cranial and postcranial anatomy of Fruitadens in detail, providing comparisons to all other known heterodontosaurid taxa. High resolution micro-CT data provides new insights into tooth replacement and the internal anatomy of the tooth-bearing bones. Moreover, we provide a preliminary functional analysis of the skull of late-surviving heterodontosaurids, discuss the implications of Fruitadens for current understanding of heterodontosaurid monophyly, and briefly review the evolution and biogeography of heterodontosaurids., Conclusions/significance: The validity of Fruitadens is supported by multiple unique characters of the dentition and hindlimb as well as a distinct character combination. Fruitadens shares highly distinctive appendicular characters with other heterodontosaurids, strengthening monophyly of the clade on the basis of the postcranium. Mandibular morphology and muscle moment arms suggest that the jaws of late-surviving heterodontosaurids, including Fruitadens, were adapted for rapid biting at large gape angles, contrasting with the jaws of the stratigraphically older Heterodontosaurus, which were better suited for strong jaw adduction at small gapes. The lack of wear facets and plesiomorphic dentition suggest that Fruitadens used orthal jaw movements and employed simple puncture-crushing to process food. In combination with its small body size, these results suggest that Fruitadens was an ecological generalist, consuming select plant material and possibly insects or other invertebrates.

Uniquely among extant vertebrates, birds possess complex respiratory systems characterised by the combination of small, rigid lungs, extensive pulmonary air sacs that possess diverticula that invade (pneumatise) the postcranial skeleton, unidirectional ventilation of the lungs, and efficient crosscurrent gas exchange. Crocodilians, the only other living archosaurs, also possess unidirectional lung ventilation, but lack true air sacs and postcranial skeletal pneumaticity (PSP). PSP can be used to infer the presence of avian-like pulmonary air sacs in several extinct archosaur clades (non-avian theropod dinosaurs, sauropod dinosaurs and pterosaurs). However, the evolution of respiratory systems in other archosaurs, especially in the lineage leading to crocodilians, is poorly documented. Here, we use µCT-scanning to investigate the vertebral anatomy of Triassic archosaur taxa, from both the avian and crocodilian lineages as well as non-archosaurian diapsid outgroups. Our results confirm previous suggestions that unambiguous evidence of PSP (presence of internal pneumatic cavities linked to the exterior by foramina) is found only in bird-line (ornithodiran) archosaurs. We propose that pulmonary air sacs were present in the common ancestor of Ornithodira and may have been subsequently lost or reduced in some members of the clade (notably in ornithischian dinosaurs). The development of these avian-like respiratory features might have been linked to inferred increases in activity levels among ornithodirans. By contrast, no crocodile-line archosaur (pseudosuchian) exhibits evidence for unambiguous PSP, but many of these taxa possess the complex array of vertebral laminae and fossae that always accompany the presence of air sacs in ornithodirans. These laminae and fossae are likely homologous with those in ornithodirans, which suggests the need for further investigation of the hypothesis that a reduced, or non-invasive, system of pulmonary air sacs may be have been present in these taxa (and secondarily lost in extant crocodilians) and was potentially primitive for Archosauria as a whole.

A fundamental contribution of paleobiology to macroevolutionary theory has been the illumination of deep time patterns of diversification. However, recent work has suggested that taxonomic diversity counts taken from the fossil record may be strongly biased by uneven spatiotemporal sampling. Although morphological diversity (disparity) is also frequently used to examine evolutionary radiations, no empirical work has yet addressed how disparity might be affected by uneven fossil record sampling. Here, we use pterosaurs (Mesozoic flying reptiles) as an exemplar group to address this problem. We calculate multiple disparity metrics based upon a comprehensive anatomical dataset including a novel phylogenetic correction for missing data, statistically compare these metrics to four geological sampling proxies, and use multiple regression modeling to assess the importance of uneven sampling and exceptional fossil deposits (Lagerstätten). We find that range-based disparity metrics are strongly affected by uneven fossil record sampling, and should therefore be interpreted cautiously. The robustness of variance-based metrics to sample size and geological sampling suggests that they can be more confidently interpreted as reflecting true biological signals. In addition, our results highlight the problem of high levels of missing data for disparity analyses, indicating a pressing need for more theoretical and empirical work., (© 2011 The Author(s). Evolution © 2011 The Society for the Study of Evolution.)

Background: The majority of research on gait mechanics in knee osteoarthritis has focused on people with medial compartment involvement. As a result, little is known about the gait mechanics of people with the less common, lateral compartment disease., Objective: The objective of this study was to compare walking mechanics--specifically, differences in frontal-plane lower-extremity kinematics and kinetics--in people with medial knee osteoarthritis, people with lateral knee osteoarthritis, and people who were healthy., Design: A cross-sectional design was used., Methods: Fifteen people with medial knee osteoarthritis, 15 people with lateral knee osteoarthritis, and 15 people who were healthy (control group) were recruited for the study. All participants underwent a gait analysis at an intentional walking speed. The variables of interest for the study were peak frontal-plane moments and angles and angular excursions of the lower extremity during the stance phase of gait. Data were statistically analyzed with a one-way analysis of variance., Results: Participants with lateral knee osteoarthritis exhibited significantly less knee adduction excursion, lower peak knee abduction moment, and lower peak rear-foot eversion compared with the control group and the medial knee osteoarthritis group., Limitations: Participants in the control group were approximately 10 years younger than participants with knee osteoarthritis. Despite this difference, neither body mass index nor gait speed, each of which is a factor with a stronger influence on gait mechanics, differed among the groups., Conclusions: Participants with lateral knee osteoarthritis exhibited frontal-plane gait mechanics at the knee and rear foot that were different from those of participants with medial knee osteoarthritis. The results of this study may guide the development of interventions specific to treating people with lateral knee osteoarthritis.

Studies detailing the neurophysiological effects of spinal manual therapy have fueled a paradigm shift away from a strict biomechanical model. However, a recent systematic review of the temporal nature of a single session of spinal thrust manipulation found that the neurophysiological effects were only temporary. The objective of this review was to examine the temporal nature of neurophysiological effects after one session of spinal mobilization. Studies eligible for this review had to report on the temporal component of the neurophysiological effects of a single session of joint mobilization of the spine in human subjects. In order to be sure that the temporal nature of these effects was captured, the studies had to monitor neurophysiological effects for a time beyond the immediate post-treatment period. This systematic review followed the methodology for preferred reporting items for systematic reviews and meta-analyses. In order to assess the quality, strength, and importance of the included studies, the grading of recommendations assessment, development and evaluation system was used. Results of this review showed that the neurophysiological effects of a single session of spinal mobilization are mostly 5 minutes or less. An exception to these findings is hypoalgesia which may last up to 24 hours, based on one study. Continued research on small samples of healthy subjects with irrelevant immediate outcomes like salivary rate, skin conductance, and skin temperature should give way to randomized controlled trials on subjects with pain and decreased function.

The fossil record is our primary window onto the diversification of ancient life, but there are widespread concerns that sampling biases may distort observed palaeodiversity counts. Such concerns have been reinforced by numerous studies that found correlations between measures of sampling intensity and observed diversity. However, correlation does not necessarily mean that sampling controls observed diversity: an alternative view is that both sampling and diversity may be driven by some common factor (e.g. variation in continental flooding driven by sea level). The latter is known as the 'common cause' hypothesis. Here, we present quantitative analyses of the relationships between dinosaur diversity, sampling of the dinosaur fossil record, and changes in continental flooding and sea level, providing new insights into terrestrial common cause. Although raw data show significant correlations between continental flooding/sea level and both observed diversity and sampling, these correlations do not survive detrending or removal of short-term autocorrelation. By contrast, the strong correlation between diversity and sampling is robust to various data transformations. Correlations between continental flooding/sea level and taxic diversity/sampling result from a shared upward trend in all data series, and short-term changes in continental flooding/sea level and diversity/sampling do not correlate. The hypothesis that global dinosaur diversity is tied to sea-level fluctuations is poorly supported, and terrestrial common cause is unsubstantiated as currently conceived. Instead, we consider variation in sampling to be the preferred null hypothesis for short-term diversity variation in the Mesozoic terrestrial realm.

The ascent of dinosaurs in the Triassic is an exemplary evolutionary radiation, but the earliest phase of dinosaur history remains poorly understood. Body fossils of close dinosaur relatives are rare, but indicate that the dinosaur stem lineage (Dinosauromorpha) originated by the latest Anisian (ca 242-244 Ma). Here, we report footprints from the Early-Middle Triassic of Poland, stratigraphically well constrained and identified using a conservative synapomorphy-based approach, which shifts the origin of the dinosaur stem lineage back to the Early Olenekian (ca 249-251 Ma), approximately 5-9 Myr earlier than indicated by body fossils, earlier than demonstrated by previous footprint records, and just a few million years after the Permian/Triassic mass extinction (252.3 Ma). Dinosauromorph tracks are rare in all Polish assemblages, suggesting that these animals were minor faunal components. The oldest tracks are quadrupedal, a morphology uncommon among the earliest dinosauromorph body fossils, but bipedality and moderately large body size had arisen by the Early Anisian (ca 246 Ma). Integrating trace fossils and body fossils demonstrates that the rise of dinosaurs was a drawn-out affair, perhaps initiated during recovery from the Permo-Triassic extinction.

Objective: To determine the association between prescription nonadherence and the health of older adults with 1 or more of 5 chronic conditions., Study Design: Analysis of the correlation between prescription nonadherence and the health of older adults., Methods: Data were from a 7-year panel with information on healthcare encounters and prescriptions. We used fixed-effects Cox duration regression models and fixed-effects Poisson count regression models to control for time-invariant factors specific to each subject when examining the impact of nonadherence on time to an emergency department (ED) visit (Cox regression) or number of ED visits (Poisson count regression)., Results: Nonadherence was associated with subsequent ED visits for hypertension, chronic heart disease, diabetes, and hypercholesterolemia. No significant short-term effects of nonadherence on chronic obstructive pulmonary disease (COPD) were detected. However, long-term effects of nonadherence (using the count regression model with lagged counts) were detected for COPD, as well as for hypertension, diabetes, and hypercholesterolemia., Conclusions: Medicinal adherence was important for all 5 conditions analyzed here. A year of nonadherence had the same correlation with ED use as making an older adult 1 year older.

Background: Archosaurs (birds, crocodilians and their extinct relatives including dinosaurs) dominated Mesozoic continental ecosystems from the Late Triassic onwards, and still form a major component of modern ecosystems (>10,000 species). The earliest diverse archosaur faunal assemblages are known from the Middle Triassic (c. 244 Ma), implying that the archosaur radiation began in the Early Triassic (252.3-247.2 Ma). Understanding of this radiation is currently limited by the poor early fossil record of the group in terms of skeletal remains., Methodology/principal Findings: We redescribe the anatomy and stratigraphic position of the type specimen of Ctenosauriscus koeneni (Huene), a sail-backed reptile from the Early Triassic (late Olenekian) Solling Formation of northern Germany that potentially represents the oldest known archosaur. We critically discuss previous biomechanical work on the 'sail' of Ctenosauriscus, which is formed by a series of elongated neural spines. In addition, we describe Ctenosauriscus-like postcranial material from the earliest Middle Triassic (early Anisian) Röt Formation of Waldhaus, southwestern Germany. Finally, we review the spatial and temporal distribution of the earliest archosaur fossils and their implications for understanding the dynamics of the archosaur radiation., Conclusions/significance: Comprehensive numerical phylogenetic analyses demonstrate that both Ctenosauriscus and the Waldhaus taxon are members of a monophyletic grouping of poposauroid archosaurs, Ctenosauriscidae, characterised by greatly elongated neural spines in the posterior cervical to anterior caudal vertebrae. The earliest archosaurs, including Ctenosauriscus, appear in the body fossil record just prior to the Olenekian/Anisian boundary (c. 248 Ma), less than 5 million years after the Permian-Triassic mass extinction. These earliest archosaur assemblages are dominated by ctenosauriscids, which were broadly distributed across northern Pangea and which appear to have been the first global radiation of archosaurs.

The purpose of this study is to examine the peak sagittal plane joint angles and joint moments of the lower extremity during the deep squat (DS) movement of the Functional Movement Screen (FMS) to assess differences between the classifications (1,2,3). Twenty-eight participants volunteered for the study and were screened to assess their FMS score on the DS task. All participants underwent a quantitative movement analysis performing the FMS DS movement at a self-selected speed. The participants in Group 3 exhibited greater dorsiflexion excursion compared to those in Group 1. Participants in Group 3 had greater peak knee flexion and knee flexion excursion than those in Group 2 who exhibited more than the participants in Group 1. Group 3 also exhibited a greater peak knee extension moment compared to Group 1. At the hip, Groups 3 and 2 exhibited greater peak hip flexion, hip flexion excursion and peak hip extension moment compared to Group 1. Thus, it appears that individuals who score differently on the deep squat as determined by the FMS exhibit differences in mechanics that may be beneficial in assessing strategies for interventions. Future research should assess how fundamental changes in mobility and stability independently affect DS performance.

Background: Numerous study results vary when analyzing the relationship between labor induction and the likelihood of cesarean delivery; and few have accounted for the multiple influences of maternal sociodemographic characteristics combined with the provider and hospital in subsequent birth outcomes such as cesarean section., Objective: This study evaluated the likelihood of cesarean birth following labor induction while accounting for maternal, hospital, and provider characteristics., Methods: A cross-sectional retrospective descriptive design using secondary data was employed to determine what variation in cesarean births was due to differences of hospitals, providers, and patients using the Quality Health Outcomes Model (QHOM). Data were partitioned by primiparous and multiparous women. The individual demographic, system, and provider outcomes in all hospitals and single birth center for Maricopa County in 2005 (N=62,816) were analyzed, using both random effects and fixed effects models., Results: For primiparous women, an increased likelihood of cesarean births was associated with medical inductions, maternal age, being Black, and the number of prenatal visits; and less likely in teaching hospitals and women with higher educational attainment. In multiparous women, cesarean births were associated with increased maternal age and medical inductions; and less likely in for-profit hospitals and following elective induction., Discussion: Labor inductions were associated with an increased likelihood of cesarean sections based on parity, age, race, number of prenatal visits, education, and hospital teaching status and ownership. Because the QHOM emphasizes multiple contextual variables that influence the delivery and outcomes of care, it can prove ideal for the study of birth outcomes following interventions such as the induction of labor., Clinical Relevance: Nurses should be well educated about the risks of elective labor induction prior to term gestation and "elective" cesarean birth.

Ceratopsians (horned dinosaurs) represent a highly diverse and abundant radiation of non-avian dinosaurs known primarily from the Cretaceous period (65-145 million years ago). This radiation has been considered to be geographically limited to Asia and western North America, with only controversial remains reported from other continents. Here we describe new ceratopsian cranial material from the Late Cretaceous of Iharkút, Hungary, from a coronosaurian ceratopsian, Ajkaceratops kozmai. Ajkaceratops is most similar to 'bagaceratopsids' such as Bagaceratops and Magnirostris, previously known only from Late Cretaceous east Asia. The new material unambiguously demonstrates that ceratopsians occupied Late Cretaceous Europe and, when considered with the recent discovery of possible leptoceratopsid teeth from Sweden, indicates that the clade may have reached Europe on at least two independent occasions. European Late Cretaceous dinosaur faunas have been characterized as consisting of a mix of endemic 'relictual' taxa and 'Gondwanan' taxa, with typical Asian and North American groups largely absent. Ajkaceratops demonstrates that this prevailing biogeographical hypothesis is overly simplified and requires reassessment. Iharkút was part of the western Tethyan archipelago, a tectonically complex series of island chains between Africa and Europe, and the occurrence of a coronosaurian ceratopsian in this locality may represent an early Late Cretaceous 'island-hopping' dispersal across the Tethys Ocean.

The fossil record is our only direct means for evaluating shifts in biodiversity through Earth's history. However, analyses of fossil marine invertebrates have demonstrated that geological megabiases profoundly influence fossil preservation and discovery, obscuring true diversity signals. Comparable studies of vertebrate palaeodiversity patterns remain in their infancy. A new species-level dataset of Mesozoic marine tetrapod occurrences was compared with a proxy for temporal variation in the volume and facies diversity of fossiliferous rock (number of marine fossiliferous formations: FMF). A strong correlation between taxic diversity and FMF is present during the Cretaceous. Weak or no correlation of Jurassic data suggests a qualitatively different sampling regime resulting from five apparent peaks in Triassic-Jurassic diversity. These correspond to a small number of European formations that have been the subject of intensive collecting, and represent 'Lagerstätten effects'. Consideration of sampling biases allows re-evaluation of proposed mass extinction events. Marine tetrapod diversity declined during the Carnian or Norian. However, the proposed end-Triassic extinction event cannot be recognized with confidence. Some evidence supports an extinction event near the Jurassic/Cretaceous boundary, but the proposed end-Cenomanian extinction is probably an artefact of poor sampling. Marine tetrapod diversity underwent a long-term decline prior to the Cretaceous-Palaeogene extinction.

Introduction: Case-mix adjustments for treatment/rehabilitation costs and benefits of non-traumatic injuries, such as occupational back pain, are much more difficult than adjustments for traumatic injuries. We present a new method for adjusting for severity differences in the costs and benefits of treating occupational low back injuries., Methods: Using initial post-injury differences in the health capital of prospective sample of 1,831 occupational related back pain patients, we combine survey data with workers' compensation claim files and medical billing information to adjust the costs and benefits of treatment using multivariate techniques., Results: We find that large differences in the net benefits of treatment between the three lowest cost provider groups virtually disappear once adjustments are made for worker's health capital (injury severity) at entry into treatment., Conclusions: Once adjustments are made for initial health capital immediately after injury, the net benefits of treating occupational low back pain are virtually identical for physician only care, physician plus physical therapy care, and chiropractic care. Net benefits of care are lower for combined physician/chiropractic care, and lowest for all other forms of care (principally, treatment by orthopedic surgeons). Our method is readily adapted for comparisons among individual health care/occupational rehabilitation professionals or among group practices and other health care organizations.

The extremes of dinosaur body size have long fascinated scientists. The smallest (<1 m length) known dinosaurs are carnivorous saurischian theropods, and similarly diminutive herbivorous or omnivorous ornithischians (the other major group of dinosaurs) are unknown. We report a new ornithischian dinosaur, Fruitadens haagarorum, from the Late Jurassic of western North America that rivals the smallest theropods in size. The largest specimens of Fruitadens represent young adults in their fifth year of development and are estimated at just 65-75 cm in total body length and 0.5-0.75 kg body mass. They are thus the smallest known ornithischians. Fruitadens is a late-surviving member of the basal dinosaur clade Heterodontosauridae, and is the first member of this clade to be described from North America. The craniodental anatomy and diminutive body size of Fruitadens suggest that this taxon was an ecological generalist with an omnivorous diet, thus providing new insights into morphological and palaeoecological diversity within Dinosauria. Late-surviving (Late Jurassic and Early Cretaceous) heterodontosaurids are smaller and less ecologically specialized than Early (Late Triassic and Early Jurassic) heterodontosaurids, and this ecological generalization may account in part for the remarkable 100-million-year-long longevity of the clade.

The Functional Movement Screen (FMS) is a series of 7 tests that categorize fundamental movement. Each test is scored on an ordinal scale with 4 categories. The purpose of this study was to determine the interrater reliability of the FMS. Forty healthy subjects were videotaped while performing the FMS. The videos were independently scored by 4 raters, including 2 experts who instruct FMS training courses and 2 novices who completed a standardized training course on the FMS. Interrater reliability was analyzed using the weighted kappa statistic. The novice raters demonstrated excellent or substantial agreement on 14 of the 17 tests, whereas the expert raters did the same on 13 of the 17 tests. When the novice raters were paired with the expert raters, all 17 components demonstrated excellent or substantial agreement. These data indicate that the FMS can confidently be applied by trained individuals. This would suggest that the FMS can be confidently used to assess the movement patterns of athletes and to make decisions related to interventions for performance enhancement, and the FMS may assist in identifying athletes at risk for injury.

Patterns of postcranial skeletal pneumatization (PSP) indicate that pterosaurs possessed components of a bird-like respiratory system, including a series of ventilatory air-sacs. However, the presence of PSP in the oldest known pterosaurs has not been unambiguously demonstrated by previous studies. Here we provide the first unequivocal documentation of PSP in Late Triassic and earliest Jurassic pterosaurs. This demonstrates that PSP and, by inference, air-sacs were probably present in the common ancestor of almost all known pterosaurs, and has broader implications for the evolution of respiratory systems in bird-line archosaurs, including dinosaurs.

Background: Individuals who sustain a rupture of the anterior cruciate ligament (ACL) are at an increased risk for developing early-onset knee osteoarthritis (OA). The mechanism behind the early onset of the disease is still unknown. Knee OA progression has been previously examined by calculating the internal knee-abduction moment during gait. However, knee-joint moments have not been examined in individuals after ACL reconstruction as a potential mechanism for disease progression in early knee OA., Objective: To determine if individuals who have undergone ACL reconstruction exhibit altered gait mechanics that may be associated with knee OA progression., Methods: In total, 17 people who had previously undergone ACL reconstruction were enrolled in the study. A matched control group was recruited for comparison. All participants underwent gait analysis at an intentional walking speed to examine variables previously associated with knee OA progression, primarily the internal peak knee-abduction moment, during gait. One way ANOVAs were performed to examine differences in gait mechanics between the two groups. All joint moments were calculated as internal moments., Results: The peak knee-abduction moment was increased by 21% in the ACL compared with the control group (p = 0.04). No other differences were seen in frontal plane knee or hip mechanics., Conclusion: It seems that individuals who have undergone ACL reconstruction exhibit an increased peak knee-abduction moment that may establish a potential mechanism of the earlier onset of knee OA in this population.

This study compared cardio-respiratory responses during running wearing a motion control shoe (MC) or a cushioning shoe (CU) in a cross-over single blinded design. Fourteen runners (10F/4M, age=27.3+/-5.1 years, body mass=64.1+/-12.2 kg, height=167.8+/-7.5 cm, VO (2)max=52.3+/-8.8 ml/kg/min) completed a 40-min run at approximately 65% VO (2) max under both shoe conditions. Oxygen uptake (mL/kg/min; L/min), minute ventilation (L/min), respiratory exchange ratio, and heart rate were measured at minutes 8-10, 18-20, 28-30 and 38-40 of exercise. Rating of perceived exertion was obtained at minutes 10, 20, 30 and 40. Two (footwear) by four (time) repeated measures ANOVAs showed no differences between footwear conditions in overall oxygen consumption (MC=36.8+/-1.5 vs. CU=35.3+/-1.4 mL/kg/min, p=0.143), minute ventilation (MC=50.4+/-4 vs. CU=48.5+/-3.8, p=0.147), respiratory exchange ratio (MC=0.90+/-0.01 vs. CU=0.89+/-0.01, p=0.331), heart rate (MC=159+/-3 vs. CU=160+/-3, p=0.926), or rate of perceived exertion. The design of motion control footwear does not appear to affect cardio-respiratory or perceived exertion responses during submaximal running. The findings are specific to the shoes tested. Nonetheless, the outcomes suggest that footwear selection to reduce certain overuse injuries does not increase the work of running.