Leg Position Research Articles

Variation in Neonate Swaddling Techniques.

It is common practice for healthcare practitioners to swaddle infants in newborn nursery and neonatal intensive care unit settings. Despite the widespread use of this practice, the American Academy of Pediatrics neither bans nor recommends swaddling. To date, there has been no standard protocol developed for either healthcare professionals or parents to establish optimal swaddling techniques in terms of infant arm positioning, infant leg positioning, and tightness of wrap. To evaluate the variability in swaddling techniques used for infants in the newborn nursery and neonatal intensive care unit. Across 2 pediatric hospitals, the swaddling positioning of each open-crib infant in the newborn nursery and neonatal intensive care unit was examined. For each infant, the following data were collected: gender, left and right arm position, left and right leg position, and tightness of wrap. In total, 132 swaddle observations were recorded. There was significant variability in swaddling positioning of arms and legs. The most common combination of arm/leg positioning was "mixed arm positioning" and "both legs flexed" (25.0% of all observations). In 9.1% of cases, tightness of wrap around chest was "tight," and in 30.3% of cases, tightness of wrap around legs was "tight." There was a large variability in swaddling positioning of both arms and legs. For such a widespread practice, the lack of medical guidelines results in inconsistent, and potentially harmful, positioning. Parents and healthcare professionals would benefit from specific, research-driven guidelines regarding proper swaddling techniques. Different variations on swaddling should be evaluated for consideration of best practice swaddling.

Optimizing Energy Harvesting for Foot Based Wearable Sensors.

Wearable devices have the potential to improve healthcare, but suffer from significant barriers to adoption, including the need for constant recharging. Harvesting energy from the ambient environment to top-up batteries can overcome this, but the actual energy available is very small, and hence it is critical that the whole system is highly optimized. This paper presents an investigation into the optimization of inertial energy harvesters for placement at the human foot. Lower body locations have previously been shown to be very energy dense, however previous energy harvester modeling has focused on the lower leg rather than the foot itself for ease of device placement. We show that the typical energy density can be almost double at the foot compared with lower leg positions, with substantially more energy concentrated in a smaller bandwidth. There is thus a dual benefit of placing a harvester at the foot: there is more energy due to the larger movement of the foot, and more efficient (higher Q) harvesters can be used to increase the collected energy. We place these results in context by analyzing the power demands of a typical wearable, and identify that with appropriate harvester tuning the peak current requirements of the electronics can be fitted into the energy peaks generated from each footstep.

The mechanical leg response to vibration stimuli in cave crickets and implications for vibrosensory organ functions.

We investigate the influence of leg mechanics on the vibration input and function of vibrosensitive organs in the legs of the cave cricket Troglophilus neglectus, using laser Doppler vibrometry. By varying leg attachment, leg flexion, and body posture, we identify important influences on the amplitude and frequency parameters of transmitted vibrations. The legs respond best to relatively high-frequency vibration (200-2000Hz), but in strong dependence on the leg position; the response peak shifts progressively over 500-1400Hz towards higher frequencies following leg flexion. The response is amplified most strongly on the tibia, where specialised vibrosensory organs occur, and the response amplitude increases with the increasing frequency. Leg responses peaking at 800 and 1400Hz closely resemble the tuning of the intermediate organ receptors in the proximal tibia of T. neglectus, which may be highly sensitive to positional change. The legs of free-standing animals with the abdomen touching the vibrating substrate show a secondary response peak below 150Hz, induced by body vibration. Such responses may significantly increase the sensitivity of low-frequency receptors in the tibial accessory organ and the femoral chordotonal organ. The cave cricket legs appear suitable especially for detection of high-frequency vibration.

Balance and Lower Limb Muscle Activation between In-Line and Traditional Lunge Exercises.

In-line and traditional lunge exercises present differences in technique as lower limb positioning (anterioposterior), and medio-lateral (ML) balance may differentially affect primary and stabilizer muscles. The purposes of this study were to examine ML balance and muscle activation in anterior and posterior leg positions between in-line and traditional lunge exercises. Fifteen young, healthy, resistance-trained men (25 ± 5 years) performed 2 different lunge exercises (in-line and traditional) at their 10 repetition maximum in a randomized, counterbalanced fashion. Surface electromyography measured muscle activation of the vastus lateralis, biceps femoris, gluteus maximus, and gluteus medius. ML balance was measured with a Wii Fit Balance Board. The vastus lateralis activity was not significantly different between exercises or leg positions. The biceps femoris activity was not significantly different between exercises, however, it was significantly greater in the anterior compared to the posterior position for the in-line (p = 0.003), and traditional lunge (p < 0.001). The gluteus maximus activity was not significantly different between exercises, however, it was significantly greater in the anterior compared to posterior position for the in-line (p < 0.001) and traditional lunge (p < 0.001). ML balance was significantly greater in the in-line exercise in the anterior limb (p = 0.001). Thus, both in-line and traditional lunge exercises presented similar overall levels of muscle activation, yet the anterior limb generated the highest biceps femoral and gluteus maximus muscle activation when compared to the posterior limb. The in-line lunge presents greater ML balance when compared to the traditional lunge exercise.

The Effect of Different Intensity and Duration of Running on Balance in Male Football Player

The aim of study was to investigate the static and dynamic balance performance after different intensity and duration of running. Fifteen male football player (a=21.6 p 0.9 y, h=172.4 p 6.1 cm, w=68.4 p 6.7 kg) participated. Conconi test on treadmill and variables of different exercises (Aerobic, Anaerobic, Mixed, Prolonged Intermittent and Super Maximal Intermittent) were measured. Then before and after each exercise participants did Y balance test (YBT), balance error scoring system (BESS), and rating of perceived exertion (RPE). Repeated measure ANOVA was used to data analysis. Results showed no significant difference in double leg position on firm surface after various exercises (p<0.05). However, static balance on firm and foam surfaces in single leg and tandem positions decreased after all exercises (p<0.05). Although, balance impairment was more noticeable after anaerobic, mixed and super maximal intermittent exercises (p<0.05). Dynamic balance declined in three direction after all exercises and the most outstanding decrease occurred after anaerobic exercise in anterior direction (p<0.05). Thus, during balance assessment, intensity and duration of exercise and balance positions should considered evaluating sport performance and clinical application.

Experimental FSI study of adaptive shock control bumps

The shock stabilisation and wave drag reduction potential of a two-dimensional adaptive shock control bump has been studied in the Imperial College supersonic wind tunnel. The bump was modelled as a flexible aluminium alloy plate deformed through spanwise actuation, and several bump heights were tested beneath a Mach 1.4 transonic shock wave. Schlieren images and static pressure readings along the flexible plate allowed the study of the λ-shock structure generated by the bifurcation of the normal shock for a range of shock positions. All bumps tested were found to increase shock stability, but wave drag reduction was only observed for shocks close to the leading edge of the flexible plate. Positive deformations of the flexible plate for downstream shocks are believed to reduce supersonic flow reacceleration, and hence the strength of the rear leg of the λ-shock and wave drag, in comparison to a solid bump with the same shape. The position of the rear leg of the λ-shock was found to exhibit a bistable behaviour, and this is hypothesised to be caused by a complex coupling of aerodynamic and structural instabilities.

Novel body positioning maximizes femoral venous size in adults: An ultrasonographic evaluation

Introduction: Increased femoral vein size may lead to a higher first pass success rate during central venous cannulation. The aim of this study was to evaluate the effects of body position on femoral vein anatomy for cannulation. Methods: This prospective study examined the femoral vein of healthy volunteers by ultrasound scanner. The changes in cross-sectional area and diameter of the femoral vein were evaluated. Right-sided measurements were taken at four different leg positions: neutral, frog leg, back-up, and back-up/frog leg position. Results: A total of 50 subjects were enrolled in the study. The mean femoral vein cross-sectional area were 0.57 ± 0.29 cm2, 0.90 ± 0.26 cm2, 1.05 ± 0.33 cm2, and 1.47 ± 0.34 cm2, and the mean femoral vein diameter were 0.75 ± 0.20 cm, 1.05 ± 0.28 cm, 1.25 ± 0.21 cm, and 1.46 ± 0.25 cm in order of neutral, back-up, frog leg, and back-up/frog leg position (p &lt; 0.001). Conclusion: Performing the right femoral vein catheterization in back-up and frog leg position is associated with a greater cross-sectional area of the femoral vein.

The walking robots critical position of the kinematics or dynamic systems applied on the environment model

The exposure is dedicated in the first to mathematical modeling of the environment where the aspects on the walking robots evolution models are described. The environment’s mathematical model is defined through the models of kinematics or dynamic systems in the general case of systems that depend on parameters. The important property of the dynamic system evolution models that approach the phenomenon from the environment is property of separation between stable and unstable regions from the free parameters domain of the system. Some mathematical conditions that imply the separation of stable regions from the free parameters domain of the system are formulated. In the second part is described our idea on walking robot kinematics and dynamic models with aspects exemplified on walking robot leg. An inverse method for identification of possible critical positions of the walking robot leg is established.

Ureteroscopic holmium laser-assisted retrograde nephrostomy access: a novel approach to percutaneous stone removal.

Percutaneous nephrolithotomy remains a challenging procedure primarily due to difficulties obtaining access. Indeed, few urologists obtain their own access due to difficulties using a fluoroscopic or ultrasonic based antegrade puncture technique. Herein we report the first experience using holmium laser energy to obtain access in a retrograde fashion. After a pretreatment week of tamsulosin 0.4mg/day (one center only) and following a documented sterile urine, a total of ten patients underwent retrograde holmium laser-assisted endoscopic-guided nephrostomy access in a prone split leg position. In nine of ten patients, ureteroscopic guided, holmium laser access via an upper pole posterior calyx was achieved. In one patient, the laser tract could not be safely dilated and antegrade endoscopic and fluoroscopic guided access was performed. The mean operative time was 202min; the mean fluoroscopy time was 32s (6/9 cases). The mean pre-operative stone volume was 14,420mm3. CT imaging on post-operative day 1 revealed 6/6 patients had residual stone fragments with total mean volume of 250mm3 (96% reduction); there were no residual fragments in three patients who were evaluated with non-CT radiographic imaging (KUB). There was a single complication requiring angioembolization due to a subcapsular hematoma with associated secondary tearing of an inter-polar vessel remote from the nephrostomy site. Holmium laser-assisted endoscopic-guided retrograde access in a prone split-leg position was successfully performed at two institutions. The accuracy of nephrostomy placement and lessening of fluoroscopy time are two potential benefits of this approach.

Incidence of deformations of the extremities of Simmental cows in different types of stalls

Problems with legs and various forms of lameness of cows, in intensive milk production, are the third significant problem occuring in this production, after mastitis and reproductive disorders, both globally and in our country. The paper analyzes the incidence of the deformation of legs of 145 cows of the Simmental breed in the Kolubara region, and the influence of paragenetic factors (housing/holding and type of stall/bedding and lactation) on the incidence of deformations. The obtained results show that, of the total number of cows assessed, 3.45% had "X" position of the front legs, 14.8% had a "X" position of the hind legs. The convergent position of the front legs was recorded in 35.86%, and divergent in 8.28% of animals. The convergent position of the hind legs was observed in 16.55% of cows, and divergent in 2.76%. The outward position of the front legs was observed in 4.14% of cows, inward position in 11.03%, and broad position in 4.14% of studied cows. Also, 17.24% of the cows had a so called sable like position of hind legs, and 7.59% showed steap angle of hind legs. The pronounced soft front leg pasterns were observed in 7.59% of the cows, and the soft pasterns of the hind legs in 33.79% of the total number of observed cows. The observed changes in the ankles in the shape of swelling were recorded in 1.38% of cattle on the carpal joint and 2.76% on the tarsal ankle. The damaged shoulder and body joint (scabbed shoulder) was observed in 43.45% of the total number of cows evaluated. Scores for the front and hind legs front, back and side views, varied at different levels of significance under the influence of the type of stall/bedding, while the scores for the condition of the hind leg pasterns varied highly significantly (p&lt;0.001) under the influence of the type of stall/bedding. The scores for the front leg pasterns and scores for shoulder and body joint were not significant (p&gt; 0.05) depending on the type of stall/bedding and the method of housing/holding of cows.

The influence of leg positioning on the appearance and quantification of 1H magnetic resonance muscle spectra obtained from calf muscle.

PurposeTo study proton magnetic resonance spectra (1H-MRS) of the muscle metabolite of a leg muscle in neutral (NEU), internal rotation (INT), and external rotation (EXT) leg positioning.Material and methodsThe volunteers were selected for this study. The tibialis anterior (TA), soleus (SOL), and gastrocnemius (GAS) muscles of a non-dominate leg were determined by using single-voxel spectroscopy 8 × 8 × 20 mm3 in size. 1H-MRS measurements were performed on a 1.5-Tesla magnetic resonance imaging (MRI) scanner.ResultsThe results showed that metabolite spectrum of muscle in each NEU, INT, and EXT of leg positioning were not similar. Additionally, the quantification of IMCL (CH3) and EMCL (CH3) is significantly different in SOL.ConclusionsOur study showed that leg positioning influences the appearance and quantification of 1H-MRS in the calf muscle. Hence, it is necessary to pay close attention to positioning because it interferes with spectral fitting and quantification.

ALMIS anterolateral hip approach using a different table and legs position during femoral exposure; New surgical technique

ALMIS anterolateral hip approach using a different table and legs position during femoral exposure; New surgical technique

Variability of fundament traits in primiparous simmental heifers

Visual evaluation and recognition of dairy traits of cows are preliminary indicators of milk yield, longevity, and reproductive ability of the individual animal, which is very important from the aspect of the economics of milk production. The deficiencies in the fundament traits lead to poor production, poor health and premature culling of cows from the herd. The paper examines the frequency of preferred scores of a certain trait in the first calving heifers according to the housing method (animals reared by individual agricultural producers and farm animals) and their origin (domestic and imported animals), as well as the impact of these two factors on the observed properties. Four fundament traits were analysed: the position of the hind legs, the development of the hocks/joints, the pastern joints and the height of the feet on a total of 954 first-calving Simmental heifers. Observed by the housing method, the higher frequency of the preferred scores for all of the fundament traits, was achieved by the farm cows, while according to the origin of the cows, the higher frequency of the preferred scores for all of the fundament traits was realized by imported animals in relation to domestic cows. The influence of the factors of the housing method and origin of animals examined by ?2 test on all the tested linear scores (frequency of scores) of the fundament traits was statistically very significant (p?0.001), while the analysis of the variance (F test) determined high significance (p?0.001) of the interaction between the origin and housing method on the height of the feet, as well as significant effect (p?0.05) on the position of the hind legs, while on other linear scores of the fundament traits it did not exhibit statistical significance (p&gt;0.05).

A Study on contact positions of hind legs for a simple quadruped walking powered exoskeleton

A Study on contact positions of hind legs for a simple quadruped walking powered exoskeleton

Three-Dimensional Feature-Enhanced Network for Automatic Femur Segmentation.

Automatic femur segmentation from computed tomography volume is a crucial but challenging task for computer-aided diagnosis in orthopedic surgeries. The main obstacles are weak bone boundaries, narrowness of joint space, variations in femur density and shape, as well as diverse leg postures. In this paper, we presented a novel 3-D feature-enhanced network to address these challenges. The novelty of our approach lies in two feature enhancement modules, including the edge detection task and the multi-scale features fusion. First, the edge detection task was embedded into femur segmentation from computed tomography volume to solve the problems of narrow joint space and weak femur boundary. Crucially, a task-specific edge detector was used to optimize the performance of femur segmentation in an end-to-end trainable system. Second, the multi-scale features fusion provided both local and global contexts to handle the problems of large variations in leg postures as well as femur shape and density. The results demonstrated that accurate 3-D femur segmentation with a high Dice similarity coefficient of 96.88% was achieved using the developed method, and the segmentation of computed tomography volume took 0.93 s on an average.

Profiling Single-Leg Balance by Leg Preference and Position in Rugby Union Athletes.

Our aims were to assess single-leg balance in rugby union athletes and compare the stability indices between legs and between positions. Thirty athletes, forwards and backs (n = 15/15), performed single-leg balance measured at two difficulty levels (Level 8: more stableand Level 2: less stable) using the Biodex Balance SD System. The backs' nonpreferred leg had worse scores in medial-lateral and overall indices (effect size = 1.05 and 0.63) compared with the preferred leg on Level 8 stability. Backs had better scores in all indices in the preferred (effect size = -1.20 to -1.82) and nonpreferred (effect size = -0.66 to -1.36) legs compared with the forwards at both stability difficulties. Asymmetry between the two legs is also present between forwards and backs when examined on an individual basis. This study illuminates the importance of single-leg balance screening among rugby athletes to detect individuals with asymmetries in balance that may increase the risk of lower-extremity injury.

Effect of Bottom Leg Position on Hip Abductor Muscles Activity During Side-lying Hip Abduction

Effect of Bottom Leg Position on Hip Abductor Muscles Activity During Side-lying Hip Abduction

The wasp larva's last supper: 100 million years of evolutionary stasis in the larval development of rhopalosomatid wasps (Hymenoptera: Rhopalosomatidae)

Abstract. Rhopalosomatidae are an unusual family of wasps (Hymenoptera: Aculeata) comprising less than 100 species found in the tropics and subtropics of all continents except Europe and Antarctica. Whereas some species resemble nocturnal Ichneumonidae, others might be mistaken for spider wasps or different groups of brachypterous Hymenoptera. Despite their varied morphology, all members of the family supposedly develop as larval ectoparasitoids of crickets (Orthoptera: Grylloidea). Here, we report on the first record of a fossil rhopalosomatid larva which was discovered in mid-Cretaceous amber from northern Myanmar (Burma). The larva is attached to the lateral side of a cricket between the metafemur and the abdomen, impacting the natural position of the hind leg, exactly as documented for modern species. Additionally, the larval gestalt is strikingly similar to those of extant forms. These observations imply that this behavioral specialization, e.g., host association and positioning on host, likely evolved in the stem of the family at least 100 million years ago.

Southwick angle measurements and SCFE slip severity classifications are affected by frog-lateral positioning.

Slipped capital femoral epiphysis (SCFE) is a hip disorder where the femoral head slips relative to the neck at the physis. Appropriate treatment of SCFE depends on the severity of the slip, commonly categorised using the Southwick (SW) angle. The SW angle is measured in the frog-lateral leg position, which can be painful and potentially unattainable for patients. The purpose of this study is to determine how errors in frog-lateral radiograph positioning affect measured SW angles and slip classifications. Models of SCFE hips were produced from one CT scan of a normal hip; 360 deformities were created. SW angles were measured from a simulated frog-lateral position. Femoral lateral head-neck angles (LHNA; equivalent to SW in incorrect frog-lateral plane) were measured over a range of 837 incorrect frog-lateral leg positions with positioning errors in flexion and/or internal/external rotation. Seventy-six per cent of all imaging position-deformity combinations had error in the reported angle (>1° difference between LHNA and SW). Of those, 70% had <5°, 24% had 5° to 10°, and 6% had >10° of error from the actual SW angle. Three per cent of LHNAs that had >10° error resulted from <10° of positioning error. If the patient is limited in flexion or external rotation, more diagnostic testing should be considered if error in the reported slip measurement would affect treatment decisions or if accurate severity classification is needed for research. Small positioning errors in moderate and severe slips can cause a>10° LHNA error; additional three-dimensional imaging should be considered.

Cross-sectional area of the femoral vein varies with leg position and distance from the inguinal ligament.

PurposeThe risk of complications associated with femoral venous catheterization could be potentially reduced if the procedure was performed at the location where the cross-sectional area (CSA) of the vessel is the largest. The diameter of the femoral vein depends on leg position as well as the distance from the inguinal ligament. We determined the CSA of the right femoral vein in three different leg positions at two distances from the inguinal ligament.Subjects and methodsInformed consent was given by 205 healthy volunteers aged 19–39 years, mean: 23±3 years (108 women, 97 men). Ultrasonographic examinations were performed using a linear 14-MHz transducer with CSA measurements in three leg positions: abduction, abduction+external rotation, abduction+external rotation+90° knee flexion/frog-leg position; at levels 20 mm caudally to the inguinal ligament, and 20 mm caudally to the inguinal crease.ResultsWe found significant differences in mean values of CSA in three leg positions regardless of the measurement level. The largest mean CSA (114 mm2±35 mm2) was found at the proximal level in the frog-leg position. There was a significant association of the CSA with sex and height. The CSA in males was greater than in females in all leg positions at the level of 20 mm caudally to the inguinal crease, while 20 mm caudally to the inguinal ligament the CSA was larger in females. The CSA of 25% of the femoral vein was smaller than 45.0 mm2 at the proximal level, and 31.5 mm2 at the distal level, which refers to diameters of 5.3 mm, and 4.5 mm, respectively.ConclusionsThe cross-sectional area of the femoral vein is the largest in the frog-leg position, and depends on gender.