A mass that has no (EBUS) echo.

We report findings for a patient that underwent endobronchial ultrasound (EBUS) guided transbronchial needle aspiration (TBNA) for diagnostic purposes after an abnormal chest CT. The patient initially presented with cough and shortness of breath. Chest CT revealed a 6 cm soft tissue mass with mildly enlarged right hilar lymph nodes (LNs) and a small right sided pleural effusion. Based on these radiologic findings, the patient underwent an EBUS guided FNA of the mass. To our surprise, the mass was hypoechoic by EBUS and on aspiration, the syringe filled with yellow fluid. This finding in combination with a re-review of the CT scans with a special focus on the Hounsfield Units of the lesion confirmed the diagnosis of a mediastinal bronchogenic cyst. This case demonstrates the role of Hounsfield units in analyzing mediastinal masses and highlights the effectiveness of EBUS guided TBNA in diagnosis and treatment of bronchogenic cysts

An Investigation of Lower-extremity Functional Asymmetry For Non-preferred Able-bodied Walking Speeds

Functional asymmetry is an idea that is often used to explain documented bilateral asymmetries during able-bodied gait. Within this context, this idea suggests that the non-dominant and dominant legs, considered as whole entities, contribute asymmetrically to support and propulsion during walking. The degree of functional asymmetry may depend upon walking speed. The purpose of this study was to better understand a potential relationship between functional asymmetry and walking speed. We measured bilateral ground reaction forces (GRF) for 20 healthy subjects who walked at nine different speeds: preferred, +10%, +20%, +30%, +40%, -10%, -20%, -30%, and -40%. Contribution to support was determined to be the support impulse: the time integral of vertical GRF during stance. Contribution to propulsion was determined to be the propulsion impulse: the time integral of the anterior-posterior GRF, while this force was directed forward. Repeated measures ANOVA (α = 0.05) revealed leg × speed interactions for normalized support (p = 0.001) and propulsion (p = 0.001) impulses, indicating that speed does affect the degree of functional asymmetry during gait. Post hoc comparisons (α = 0.05) showed that support impulse was approximately 2% greater for the dominant leg, relative to the non-dominant leg, for the -10%, -20%, and -40% speeds. Propulsion impulse was 12% greater for the dominant leg than for the non-dominant leg at the +20% speed. Speed does appear to affect the magnitude of bilateral asymmetry during walking, however, only the bilateral difference for propulsion impulse at one fast speed (+20%) supported the functional asymmetry idea

Variations in running technique between female sprinters, middle, and distance runners

International Journal of Exercise Science 6(1) : 43-51, 2013. In the sport of track and field, runners excel not only due to physiological characteristics but also aspects in running technique. Optimal technique allows runners the perfect the balance between running speed and economy. The ideal movement pattern may vary between events as the goal goes from economy of movement in the long-distance events to speed and power in the sprints. Understanding how each type of runner moves differently will help coaches more effectively train their athletes for each specific running event. This study was conducted to determine if sprinters, middle-distance, and long-distance runners would exhibit differences in form while running at the same speeds. Thirty female Division I collegiate runners participated in this study. Runners were separated into categories based on the events for which they were currently training in: 10 sprinters, 10 middle-distance, and 10 long-distance runners. Participants were asked to run twenty-two steps at five selected speeds. Knee angles, ground contact time, center of mass separation, and stride length were measured using a Vicon Nexus motion analysis system. Data was processed using analysis of variance and a Tukey post hoc analysis. Significant differences (p \u3c .05) occurred between long-distance runners and the other two groups (middle-distance and sprinters) for knee range, ground contact time, center of mass separation, and stride length at all five speeds. While running at the same speeds, there are specific characteristics of technique that distinguish long-distance runners from middle-distance and sprinters

Ground Reaction Forces Generated by Twenty-eight Hatha Yoga Postures

Int J Exerc Sci 5(2) : 114-126, 2012. Adherents claim many benefits from the practice of yoga, including promotion of bone health and prevention of osteoporosis. However, no known studies have investigated whether yoga enhances bone mineral density. Furthermore, none have estimated reaction forces applied by yoga practitioners. The purpose of this study was to collect ground reaction force (GRF) data on a variety of hatha yoga postures that would commonly be practiced in fitness centers or private studios. Twelve female and eight male volunteers performed a sequence of 28 hatha yoga postures while GRF data were collected with an AMTI strain-gauge force platform. The sequence was repeated six times by each study subject. Four dependent variables were studied: peak vertical GRF, mean vertical GRF, peak resultant GRF, and mean resultant GRF. Univariate analysis was used to identify mean values and standard deviations for the dependent variables. Peak vertical and resultant values of each posture were similar for all subjects, and standard deviations were small. Similarly, mean vertical and resultant values were similar for all subjects. This 28 posture yoga sequence produced low impact GRF applied to upper and lower extremities. Further research is warranted to determine whether these forces are sufficient to promote osteogenesis or maintain current bone health in yoga practitioners

Does Experimental Anterior Knee Pain Alter Effects of Running on Femoral Articular Cartilage Thickness and Volume? A Pilot Study

Anterior knee pain is a common problem for runners that often alters running biomechanics. It is unclear how/if changes in running biomechanics due to anterior knee pain affect knee articular cartilage health. PURPOSE: To determine if experimental anterior knee pain during running acutely alters deformation in femoral articular cartilage due to running. METHODS: 10 runners completed three sessions that each in- volved a 60-min treadmill run: a control, sham, and pain session. Experimental anterior knee pain was in- duced during the pain session via a continuous infusion of hypertonic saline into the infrapatellar fat pad. The sham and control sessions involved a continuous infusion of physiological saline and no infusion, re- spectively. Before and after running, magnetic resonance imaging was used to quantify femoral articular cartilage thickness and volume. A repeated measures ANOVA was used to evaluate effects of running with experimental anterior knee pain on perceived knee pain and femoral articular cartilage deformation (α = 0.05). RESULTS: Perceived anterior knee pain was significantly greater during the pain session relative to the control and sham sessions (p p = 0.05), and more due to the pain session run (-57.7 ± 157.4 mm3) than the control session run (p = 0.09). No significant effects of session were observed for medial or lateral thickness or lateral volume. CONCLUSION: Articular cartilage response to running (medial femoral volume) was different for the pain and sham sessions relative to the control session. The physiological and hypertonic saline infusions appeared to alter medial knee articular cartilage response to running. These changes might be due to altered biomechanics due to the infusions. Additional research is needed to clarify the cause of the altered response to running

Biomechanics Differ for Individuals With Similar Self-Reported Characteristics of Patellofemoral Pain During a High-Demand Multiplanar Movement Task

Context: Patellofemoral pain (PFP) is often categorized by researchers and clinicians using subjective self-reported PFP characteristics; however, this practice might mask important differences in movement biomechanics between PFP patients. Objective: To determine whether biomechanical differences exist during a high-demand multiplanar movement task for PFP patients with similar self-reported PFP characteristics but different quadriceps activation levels. Design: Cross-sectional design. Setting: Biomechanics laboratory. Participants: A total of 15 quadriceps deficient and 15 quadriceps functional (QF) PFP patients with similar self-reported PFP characteristics. Intervention: In total, 5 trials of a high-demand multiplanar land, cut, and jump movement task were performed. Main Outcome Measures: Biomechanics were compared at each percentile of the ground contact phase of the movement task (alpha =.05) between the quadriceps deficient and QF groups. Biomechanical variables included (1) whole-body center of mass, trunk, hip, knee, and ankle kinematics; (2) hip, knee, and ankle kinetics; and (3) ground reaction forces. Results: The QF patients exhibited increased ground reaction force, joint torque, and movement, relative to the quadriceps deficient patients. The QF patients exhibited: (1) up to 90, 60, and 35Nmore vertical, posterior, and medial ground reaction force at various times of the ground contact phase; (2) up to 4 degrees more knee flexion during ground contact and up to 4 degrees more plantarflexion and hip extension during the latter parts of ground contact; and (3) up to 26, 21, and 48 N.m more plantarflexion, knee extension, and hip extension torque, respectively, at various times of ground contact. Conclusions: PFP patients with similar self-reported PFP characteristics exhibit different movement biomechanics, and these differences depend upon quadriceps activation levels. These differences are important because movement biomechanics affect injury risk and athletic performance. In addition, these biomechanical differences indicate that different therapeutic interventions may be needed for PFP patients with similar self-reported PFP characteristics

A Review of Biophysical Differences between Aquatic and Land-Based Exercise

Four of the most popular modes of aquatic exercise are deep-water (DW) exercise, shallow water (SW) exercise, water calisthenics (WC), and underwater treadmill (UT) exercise. The mechanical requirements of each aquatic exercise mode may elicit different physiological and biomechanical responses. The purpose of this descriptive literature review was to evaluate some biophysical differences between aquatic and land-based exercises. The biophysical variables included oxygen consumption (VO2), heart rate (HR), rating of perceived exertion (RPE), stride length, stride frequency, pain, and measures of functional gain. Based on the studies reviewed, when compared to similar land-based exercises, VO2 and HR maximum values were lower during DW and SW exercise, but, depending on water depth and exercise performed, may be greater during WC and UT exercise. RPE during DW exercise was generally similar to land exercise during max effort. Stride frequency tended to be lower for all four aquatic exercises, relative to on-land counterparts. Pain levels tended to be similar between WC and land exercise, yet may decrease after UT exercise

Running Biomechanics and Knee Cartilage Health in ACLR Patients

Anterior cruciate ligament reconstruction (ACLR) patients are more likely to subsequently suffer from knee osteoarthritis than non-ACLR counterparts. Exercise is thought to influence articular cartilage, however, it is unclear how running biomechanics are associated with femoral cartilage thickness and composition in ACLR patients. PURPOSE: The purpose of this study was to investigate relationships between running biomechanics and measures of femoral articular cartilage condition (thickness and composition) in ACLR patients and control subjects. METHODS: We used ultrasound and MRI (T2 mapping sequence) to measure articular cartilage thickness and composition, respectively, for 20 ACLR patients (age: 23 ± 3 yrs; mass: 70 ± 10 kg; time post-ACLR: 14.6 ± 6.1 months) and 20 matched controls (age: 22 ± 2 yrs; mass: 67 ± 11 kg). After these measures, all participants completed a 30-minute run on a force-instrumented treadmill. Correlational analyses were used to explore relationships between running biomechanics (vertical ground reaction force (vGRF)) and femoral cartilage thickness and composition (T2 relaxation time). The present procedures were approved by the appropriate institutional board and all subjects provided informed consent before data collection was performed. RESULTS: Significant positive correlations existed for the control subjects only between peak vGRF and overall (r = 0.34; p \u3c 0.01), medial (r = 0.23; p \u3c 0.01), lateral (r = 0.39; p = 0.02), and intercondylar (r = 0.31; p \u3c 0.01) femoral thickness. The ACLR patients showed significant negative correlations between T2 relaxation time for the central-medial region of the femoral condyle, and peak vGRF (r = −0.53; p = 0.01) and vertical impulse due to the vGRF (r = −0.46; p = 0.04). CONCLUSION: These findings offer some limited support for the idea that femoral articular cartilage benefits from increase vGRF during running. This is evidenced by the increased thickness for the control subjects and decreased T2 relaxation time (indicative of increased free-flowing water in the cartilage) for the ACLR patients, as running vGRF increased

Effects of Running on Femoral Articular Cartilage Thickness for Anterior Cruciate Ligament Reconstruction Patients and Non-ACLR Control Subjects

Anterior cruciate ligament reconstruction (ACLR) patients are more likely to develop posttraumatic knee osteoarthritis than non-ACLR counterparts. The effect of running on femoral articular cartilage thickness is unclear. PURPOSE: The purpose of this study was to compare how 30 minutes of running influences femoral articular cartilage thickness for ACLR patients and non-ACLR control subjects. We hypothesized that running would deform the femoral articular cartilage more for the ACLR patients than for the control subjects. METHODS: We recruited 20 individuals with primary unilateral ACLR and 20 matched non-ACLR controls. ACLR patients and control subjects were matched based upon age, gender, BMI, and weekly running mileage. The present procedures were approved by the appropriate institutional board and all subjects provided informed consent before data collection. We used ultrasound imaging to measure femoral articular cartilage thickness before and after 30 minutes of running. The ultrasound images were manually analyzed using ImageJ software by the same investigator. Total femoral articular cartilage cross-sectional area of each image was segmented into three regions: medial, lateral, and intercondylar. Deformation due to the run was compared between the ACLR patients and control subjects for each region using independent t tests (P \u3c 0.05, adjusted for multiple comparisons). RESULTS: The 30-minute run resulted in more deformation for the ACLR patients (0.03 ± 0.01 cm) than the matched controls (0.01 ± 0.01 cm) for the medial region (p \u3c 0.01) of the femoral articular cartilage. Identically, the 30-minute run resulted in more deformation for the ACLR patients (0.03 ± 0.01 cm) than the matched controls (0.01 ± 0.01 cm; p \u3c 0.01) for an average of the entire articular cartilage area (medial, lateral, and intercondylar). No significant differences existed between groups for the lateral or intercondylar regions. CONCLUSION: Thirty minutes of running deformed medial and overall femoral articular cartilage more for ACLR patients than non-ACLR control subjects

Femoral Articular Cartilage Quality, but Not Thickness, Is Decreased for Anterior Cruciate Ligament Reconstruction Patients Relative to Control

Anterior cruciate ligament reconstruction (ACLR) patients are at risk of developing posttraumatic knee osteoarthritis (OA). The etiology of posttraumatic knee OA is complex, potentially involving biomechanical and biochemical factors. Changes in femoral cartilage thickness and composition are associated with knee OA, while current research is ambiguous on cartilage in ACLR patients. PURPOSE: This study aimed to compare femoral cartilage thickness and T2 relaxation time (a compositional measure) between ACLR patients and healthy controls in a resting state. We hypothesized that ACLR patients would exhibit thinner femoral cartilage and increased T2 relaxation times. METHODS: Twenty ACLR patients (6-24 months post-surgery) and 20 matched healthy controls were recruited following institutional board approval. Ultrasound and magnetic resonance imaging data were collected on two separate days, allowing cartilage thickness and composition measurements to be made, respectively. Statistical analyses, including independent t-tests and Holm-Bonferroni corrections, were performed on selected regions of interest. RESULTS: The ACLR group showed increased T2 relaxation times in four of eight femoral regions compared to controls. No significant differences in femoral cartilage thickness were observed between the groups. The primary finding from this study is that ACLR patients did not show differences in femoral cartilage thickness (a morphological measure), but displayed prolonged T2 relaxation times (a compositional measure) compared to controls, at rest. This finding suggests that compositional changes precede morphological shifts in femoral cartilage in early post-ACLR periods (6-24 months). CONCLUSION: These early compositional changes may indicate articular cartilage that is more compressible and subject to increased strain on the solid components of the joint. While ultrasound is a more accessible imaging method, magnetic resonance imaging may provide a more accurate and early evaluation of cartilage quality. Further research is needed to develop practical tools for early detection and monitoring of cartilage degradation in ACLR patients before progression into knee osteoarthritis