Limb Flexion Research Articles

Kinetic and kinematic strategies integrating the trunk and lower limbs for a powerful soccer kick in amateur players

ABSTRACT This study investigated the kinematic (KmS) and kinetic (KnS) strategies integrating the trunk and lower limbs to achieve maximal kicking performance. Although strategies consisting of individual joint movements or moments are known, strategies combining joint movements or moments of the trunk and lower limbs have been less studied. Fifty adult amateur soccer players were assessed. Peak joint angles and moments of the trunk, the hip of the supporting limb, the hip and knee of the kicking limb, and the velocities of the foot and ball were recorded. Canonical Correlation Analysis evaluated relationships between sets of variables. A combination of greater hip extension and knee flexion of the kicking limb, as a KmS, correlated with better kick performance (Rc = 0.60, p = 0.004). Furthermore, a combination of larger moments of trunk flexion and rotation, internal rotation of the supporting hip, hip flexion, and knee extension of the kicking limb, as a KnS, were associated with better performance (Rc = 0.74, p < 0.001). The explained variance was 43% for the KmS and 59% for the KnS. In amateur players, the KmS for better kick performance involved greater hip and knee movement of the kicking limb, while the KnS involved greater moments at the trunk and both lower limbs.

Machine Learning for Upper Limb Flexion Movement Classification

Introduction: This paper introduces the development and validation of a Machine Learning (ML) program aimed at discerning smooth and jittery arm movements during flexion/extension exercises. Objective: The study compares the efficacy of three classification algorithms—K-Nearest Neighbors (KNN), Support Vector Machine (SVM), and Logistic Regression—in differentiating flexion/extension movements with and without added weight. Method: Using a quasi-experimental design, participants voluntarily performed the exercise under two conditions: with and without a 5-kilogram dumbbell. Meticulous frame-by-frame extraction of movement parameters informed the data collection process. Results: Biomechanical analysis identified key features (minAngle, coefTrajectory, maxJerk, avgAcceleration, and frames) relevant for algorithm training. Post-normalization, KNN, Logistic Regression, and SVM demonstrated robust validation performance through metrics and confusion matrices. Detection of a userdependent data leak prompted a user-specific validation approach. Conclusion: This research amalgamates biomechanics and ML, yielding insights into algorithmic performance for detecting weighted exercises. Robust validation is crucial for ensuring the generalizability of classification models in real-world scenarios.

The Impact of Knee Bending on the Superficial Femoral Artery and Popliteal Artery Morphology Before and After Endovascular Repair of Popliteal Aneurysm.

The aim of this study is to evaluate the deformations of the femoropopliteal (FP) arterial segment due to knee flexion in patients suffering from popliteal aneurysm before and after endovascular treatment (ET). Nine patients were prospectively evaluated. Pre-operative and post-operative computed tomography angiography (CTA) scans were performed on the leg of each patient in both a flexed and extended knee position. The images were employed to reconstruct the FP segment through segmentation and the resulting models were subsequently used to calculate the average diameter, length, and tortuosity of both the superficial femoral artery (SFA) and popliteal artery (PA). Furthermore, the overall PA tortuosity was decomposed into 2 components, ie, antero-posterior and lateral direction. Following knee flexion, both arterial segments experienced shortening in the pre-operative and post-operative phases. Specifically, the SFA was shortened by 3.5% in pre (p<0.001) and 1.21% in post-stenting (p<0.001), while the PA was shortened by 4.8% (p<0.001) and 5.63% (p<0.001), respectively. Tortuosity significantly increased in all considered segments; in particular, in SFA there was a pre-intervention increase of 85.2% (p=0.002) and an increase of 100% post-intervention (p=0.004), whereas in the PA, there was an increase of 128.9% (p<0.001) and 254.8% (p<0.001), respectively. The only diameter variation occurred in the SFA pre-operatively with an increase of 11.9% (p=0.007). Tortuosity decomposition revealed significant differences between the 2 planes during the pre-operative and post-operative phases in both extended and flexed configurations, confirming a change in artery position and geometry due to treatment. Knee flexion induces arterial shortening and increased tortuosity in both the pre- and post-operative configuration. Stent placement does not induce significant geometric differences between pre-treatment and post-treatment. These results seem to indicate that the geometry of the covered stent is not affected by the flexion of the knee joint. Despite this, a more detailed analysis of arterial tortuosity showed a change in artery deformation following treatment. This study aimed to evaluate femoropopliteal arterial deformations in nine patients with popliteal aneurysm before and after endovascular treatment (ET) during knee flexion, using a standardized protocol for CTA acquisition and analysis. The result can be useful in procedure planning and have shown that the Viabahn stent used can adapt to the morphological variations induced by limb flexion. Consequently, device failure does not be attributed to stent compression but rather to other factors, such as alterations in hemodynamic and biomechanical forces on the implant due to the significant changes in tortuosity observed, or biological causes.

Testing the form-function paradigm: body shape correlates with kinematics but not energetics in selectively-bred birds

A central concept of evolutionary biology, supported by broad scale allometric analyses, asserts that changing morphology should induce downstream changes in locomotor kinematics and energetics, and by inference selective fitness. However, if these mechanistic relationships exist at local intraspecific scales, where they could provide substrate for fundamental microevolutionary processes, is unknown. Here, analyses of selectively-bred duck breeds demonstrate that distinct body shapes incur kinematic shifts during walking, but these do not translate into differences in energetics. A combination of modular relationships between anatomical regions, and a trade-off between limb flexion and trunk pitching, are shown to homogenise potential functional differences between the breeds, accounting for this discrepancy between form and function. This complex interplay between morphology, motion and physiology indicates that understanding evolutionary links between the avian body plan and locomotor diversity requires studying locomotion as an integrated whole and not key anatomical innovations in isolation.

Trial of Brain–Computer Interface for Continuous Motion Using Electroencephalography and Electromyography

Most BCI systems used in neurorehabilitation detect EEG features indicating motor intent based on machine learning, focusing on repetitive movements, such as limb flexion and extension. These machine learning methods require large datasets and are time consuming, making them unsuitable for same-day rehabilitation training following EEG measurements. Therefore, we propose a BMI system based on fuzzy inference that bypasses the need for specific EEG features, introducing an algorithm that allows patients to progress from measurement to training within a few hours. Additionally, we explored the integration of electromyography (EMG) with conventional EEG-based motor intention estimation to capture continuous movements, which is essential for advanced motor function training, such as skill improvement. In this study, we developed an algorithm that detects the initial movement via EEG and switches to EMG for subsequent movements. This approach ensures real-time responsiveness and effective handling of continuous movements. Herein, we report the results of this study.

Evaluation of the Effectiveness of In-Hospital Exercise Rehabilitation in Middle-Aged and Elderly Patients with Type 2 Diabetes Mellitus Combined with Sarcopenia Effect of Lifestyle Management on Disease Status in Patients with Type 2 Diabetes Mellitus

ABSTRACT Objective The aim of this study was to explore the effects of in-hospital exercise rehabilitation on glucose and lipid metabolism and healthy physical fitness in middle-aged and elderly patients with type 2 diabetes mellitus (T2DM) combined with sarcopenia, and to provide a reference for the effective implementation of exercise rehabilitation for middle-aged and elderly patients with T2DM combined with sarcopenia in healthcare institutions. Methods This study retrospectively included 122 patients with T2DM combined with sarcopenia treated at the General Hospital of Ningxia Medical University from August 2017 to August 2020 and randomly divided into a control group and an experimental group. The control group was given conventional treatment and the experimental group was given exercise rehabilitation in the hospital for 12 weeks to compare the indexes related to glucose and lipid metabolism and healthy fitness in the two groups. Results After the intervention, the experimental group showed significant decreases in fasting blood glucose (FBG), glycated hemoglobin (HbA1c), insulin resistance index (HOMA-IR), triglycerides (TG), total cholesterol (TC), low-density cholesterol (LDL-C) and body fat percentage (p < 0.05), while high-density cholesterol (HDL-C), grip strength, lower limb extension, lower limb flexion, peak oxygen uptake were significantly higher (p < 0.05) and were more significant at 12 weeks compared to the 6-week intervention (p < 0.05). However, there were no significant changes in any of the glucose metabolism indicators in the control group before and after the intervention. A two-way repeated measures ANOVA showed that at control baseline levels, HbA1c decreased significantly in the experimental group after both 6 and 12 weeks of intervention compared to the control group (p < 0.05). After 6 weeks of intervention, the experimental group showed a significant decrease in body fat percentage and a significant increase in grip strength. After 12 weeks of intervention, the experimental group showed an increase in glycemic control from 33.3% to 73.3%, a significant decrease in body fat percentage and a significant increase in grip strength, lower limb extension and lower limb flexion strength and peak oxygen uptake. Conclusion In-hospital exercise rehabilitation can effectively improve the glycemic and lipid profiles of patients with T2DM combined with sarcopenia and enhance their health fitness, with good clinical rehabilitation effects.

Abstract 2039: Limb Flexion Compresses The Anterior Tibial Artery And Changes Its Take-off Angle In A Sex-Dependent Manner

Introduction: Peripheral Arterial Disease (PAD) operations and reconstructions continue to fail at high rates, particularly below the knee. During limb flexion, distal superficial femoral and popliteal arteries experience significant deformations that are thought to contribute to disease development, but the biomechanics of the tibial arteries below the knee have not been characterized. Methods: Perfused human cadavers (n=15, 81±9 years old, range 60-93 years, 9F/6M) were imaged with their limbs in standing (180°), walking (110°), sitting (90°), and fetal/gardening (60°) positions using Computerized Tomography (CT). Three-dimensional geometries of the below-knee arteries were reconstructed in Mimics software and used to assess the take-off angle of the anterior tibial artery (AT) and the distance from the AT take-off to the nearest AT side branch. Results: The AT take-off angle relative to the tibioperoneal trunk increased with more acute limb flexion, from 70±19° in standing to 81±24° in walking, 83±24° in sitting, and 89±27° in fetal/gardening postures (p&lt;0.01 for all postures). The AT take-off angle was larger in females than in males (24% in standing and 35% in walking, sitting, and gardening postures, p &lt;0.01), but there were no differences between left and right limbs of either sex (p=0.66-0.99). The distance from the AT take-off to the nearest AT side branch decreased with more acute limb flexion (p&lt; 0.01 for all postures). Conclusions: Limb flexion increases the AT take-off angle in a sex-dependent manner and compresses the AT, potentially contributing to the differences in hemodynamics and arterial mechanics and affecting the development and progression of tibial artery pathology. A better understanding of the below-knee artery biomechanics can provide valuable insights for surgical planning and may lead to improvements in the success rate and durability of PAD repairs.

456 Arm Flexion to Overcome Gaps for Primary Radial Nerve Repair: An Anatomic Study

INTRODUCTION: It is now well known that direct nerve repairs fare better than grafted nerve repairs. There is currently renewed interest in direct repair of nerves achieved by limb flexion followed by serial distraction as it is the least morbid and most easily implemented surgical technique to provide extra nerve excursion. This is especially simple in the upper extremity, which can be easily immobilized post-operatively in a sling. METHODS: Four fresh and 11 fixed cadaver arms with shoulder intact were dissected to determine the relationship between degrees of EF (ranged from 0-90 degrees EF) and nerve gap length overcome with proximal excursion of the distal nerve. Additional excursion from brachialis branch neurectomy was also assessed. RESULTS: We found an approximately linear relationship between EF and RN excursion. Compliance of fresh cadaveric nerves more closely approximated that of surgical tissue. In fresh cadavers, there was 3mm of RN excursion per 10 degrees EF in the proximal half of the arm, and 4 mm excursion per 10 degrees EF with neurectomy. CONCLUSIONS: Elbow flexion can significantly augment the ability to achieve an end-to-end repair of the RN. To simplify our findings, 90-degree EF should readily overcome a RN gap of 3.5 cm, and additional brachialis neurectomy allows for total RN excursion of 4.7 cm on average in the proximal arm with 90-degrees EF. Given nerve regeneration rates of 1-2 mm/day, we recommend 14-27 days prior to full elbow extension from a RN repair performed with 90-degree EF without neurectomy, and 18-36 days for repair at 90-degree EF with neurectomy.

Structural and Mechanical Properties of Human Superficial Femoral and Popliteal Arteries.

The femoropopliteal artery (FPA) is the main artery in the lower limb. It supplies blood to the leg muscles and undergoes complex deformations during limb flexion. Atherosclerotic disease of the FPA (peripheral arterial disease, PAD) is a major public health burden, and despite advances in surgical and interventional therapies, the clinical outcomes of PAD repairs continue to be suboptimal, particularly in challenging calcified lesions and biomechanically active locations. A better understanding of human FPA mechanical and structural characteristics in relation to age, risk factors, and the severity of vascular disease can help develop more effective and longer-lasting treatments through computational modeling and device optimization. This review aims to summarize recent research on the main biomechanical and structural properties of human superficial femoral and popliteal arteries that comprise the FPA and describe their anatomy, composition, and mechanical behavior under different conditions.

Administration of sodium hyaluronate to adult horses prior to and immediately after exercise does not alter the range of motion in either the tarsus or metacarpophalangeal joints

Abstract Hyaluronic acid (HA), a glycosaminoglycan found in joint synovial fluid, is administered to horses as an anti-inflammatory with lubrication properties. This experiment examined the effects of HA administered before and shortly after an exercise test on metacarpophalangeal (MCP; fetlock) and tibiotarsal (hock) joint range of motion (ROM). Horses were injected intravenously (IV) with placebo (4 mL, saline) or HA (4 mL, 40 mg) 24 h before performing a standardized exercise test (SET) on a high-speed treadmill and again at 6-h post-SET. Passive fetlock flexion was measured at 4 and 24 h post-SET. Hock flexion and extension were measured at 24 h post-SET by videography and kinematic evaluation at the trot. Parameters of the SET were sufficient to cause peak lactate values of 6.6 ± 0.15 mM and a maximum heart rate of 203.6 ± 4.8 bpm. A minor gain (P = 0.08) in fetlock flexion prior to SET was observed in HA horses that were not retained at either 4 or 24 h post-SET. Hock flexion in both limbs was greater (P &amp;lt; 0.05) at 24 h post-SET, independent of treatment. Horses receiving HA exhibited reduced (P = 0.04) right hock extension. No differences in either right or left hock ROM were observed between control and HA-treated horses. From these results, it is concluded that IV HA injections surrounding an exercise stressor offer no substantive gains in either fetlock or hock ROM.

Risk assessment of SWEN21 a suggested new dive table for the Swedish armed forces: bubble grades by ultrasonography.

To develop the diving capacity in the Swedish armed forces the current air decompression tables are under revision. A new decompression table named SWEN21 has been created to have a projected risk level of 1% for decompression sickness (DCS) at the no stop limits. The aim of this study was to evaluate the safety of SWEN21 through the measurement of venous gas emboli (VGE) in a dive series. A total 154 dives were conducted by 47 divers in a hyperbaric wet chamber. As a proxy for DCS risk serial VGE measurements by echocardiography were conducted and graded according to the Eftedal-Brubakk scale. Measurements were done every 15 minutes for approximately 2 hours after each dive. Peak VGE grades for the different dive profiles were used in a Bayesian approach correlating VGE grade and risk of DCS. Symptoms of DCS were continually monitored. The median (interquartile range) peak VGE grade after limb flexion for a majority of the time-depth combinations, and of SWEN21 as a whole, was 3 (3-4) with the exception of two decompression profiles which resulted in a grade of 3.5 (3-4) and 4 (4-4) respectively. The estimated risk of DCS in the Bayesian model varied between 4.7-11.1%. Three dives (2%) resulted in DCS. All symptoms resolved with hyperbaric oxygen treatment. This evaluation of the SWEN21 decompression table, using bubble formation measured with echocardiography, suggests that the risk of DCS may be higher than the projected 1%.

Polioencephalopathy in Eurasier dogs.

Polioencephalopathies secondary to inborn errors of metabolism have been described in dogs, but few genetically characterized. Clinically and genetically characterize polioencephalopathy in a family of Eurasier dogs. Three Eurasier dogs (littermates) presented with early onset movement disorders (9 weeks in 2, 4-6 months in 1). Progressive gait abnormalities were detected in 2 of the dogs, persistent divergent strabismus in 1, whereas consciousness and behavior remained intact in all dogs. One dog was euthanized at 25 months. Video footage was assessed in all dogs, and Dogs 1 and 2 had examinations and investigations performed. Whole genome sequencing of Dog 1 and further genetic analyses in the family were performed. A cohort of 115 Eurasier controls was genotyped for specific variants. Episodes were characterized by generalized ataxia, as well as a hypermetric thoracic limb gait, dystonia, and irregular flexion and extension movements of the thoracic limbs. Magnetic resonance imaging of the brain in Dogs 1 and 2 identified symmetrical, bilateral T2 and fluid attenuated inversion recovery hyperintense, T1 hypo to isointense, nonenhancing lesions of the caudate nucleus, lateral and medial geniculate nuclei, thalamus, hippocampus, rostral colliculus and mild generalized brain atrophy. Genetic analyses identified a homozygous mitochondrial trans-2-enoyl-CoA reductase (MECR) missense variant in all 3 dogs, and a homozygous autophagy-related gene 4D (ATG4D) missense variant in Dogs 1 and 2. We describe a presumed hereditary and progressive polioencephalopathy in a family of Eurasier dogs. Further research is needed to establish the role of the MECR gene in dogs and the pathogenic effects of the detected variants.

Limb-specific isometric and isokinetic strength in adults: The potential role of regional bioelectrical impedance analysis-derived phase angle

Background & AimsIt is not yet known whether regional bioelectrical impedance (BIA) phase angle (PhA) may be informative of different types of strength performed by the lower and upper limbs, independently of lean soft tissue mass (LSTM). Using a sample of healthy adults, we aimed to examine the association and relevance of regional PhA relative to isometric and isokinetic strength of each limb. MethodsA total of 57 participants (32.7±12.9 years; 24.7±3.5 kg/m2) were included in the present investigation. Regional raw BIA variables were determined using a phase-sensitive BIA device. Dual-energy X-ray absorptiometry was used to evaluate LSTM. Absolute isometric and isokinetic (i.e., 60º/s and 180º/s) strength of each limb (extension and flexion) was assessed using an isokinetic dynamometer and used to calculate relative strength. ResultsIn absolute strength, only dominant leg PhA was associated with isometric extension strength (β=0.283) and isokinetic 180º/s flexion strength (β=0.354), regardless of LSTM (p<0.05). In relative strength, a significant association of regional PhA was found for dominant arm flexion isometric strength (β=0.336), and non-dominant arm and dominant leg extension isometric strength (β=0.377, β=0.565, respectively; p<0.05), independently of LSTM. Similarly, for isokinetic 180º/s strength, regional PhA significantly explained the variance in the relative strength of both arms and dominant leg (β=0.350 to 0.506), regardless of LSTM (p<0.05). Relative isokinetic 60º/s strength was not consistently associated with regional PhA (p≥0.05). ConclusionsRegional PhA significantly explained relative (isometric and 180º/s isokinetic strength of both arms and dominant leg), but not absolute muscle strength, independently of regional LSTM. Thus, after accounting for body size, regional PhA seems to have its own characteristics that explain relative strength independently of LSTM.

Children with Duchenne muscular dystrophy display specific kinematic strategies during obstacle-crossing

Duchenne muscular dystrophy (DMD) is a genetic disease characterized by progressive muscle weakness with increased neuromechanical challenge and fall risks, especially during obstructed locomotion. This study aimed to identify the kinematic strategies for obstacle-crossing in DMD via synthesizing the changes in the joint kinematics and associated end-point control. Fourteen boys with DMD (age: 9.0 ± 2.5 years) and fourteen typically developed controls (age: 9.0 ± 2.8 years) each crossed obstacles of three different heights (10%, 20% and 30% of leg length) while the angular motions of the trunk-pelvis-leg apparatus and foot-obstacle clearances were measured. Two-way analyses of variance were used to analyze group and obstacle height effects. Compared to the controls, the DMD group crossed obstacles with significantly increased step width, but decreased crossing speed, crossing step length, trailing toe-obstacle clearance and leading heel-obstacle horizontal distance (p < 0.05). When the leading toe was above the obstacle, the patients showed significantly increased pelvic hiking, pelvic and trunk anterior tilt and ankle plantarflexion, but decreased hip flexion in both limbs (p < 0.05). Similar kinematic changes were found during trailing-limb crossing, except for an additional increase in swing-hip abduction and decrease in contralateral trunk side-bending and stance-knee flexion. Patients with DMD crossed obstacles via a specific kinematic strategy with altered end-point control, predisposing them to a greater risk of tripping during trailing-limb crossing. These results suggest that crossing kinematics in DMD should be monitored—especially in the proximal segments of the pelvis-leg apparatus—that may lead to an increased risk of falling.

Electromyographic characterization of limb flexion, extension and their special exercise movements in high level distance runners

Abstract The study of EMG characteristics of high-level distance runners in limb flexion, extension, and their special exercise movements is beneficial to developing competitive distance running sports. In this study, high-level distance runners were used as the research object, and the sEMG test in EMG analysis was used to compare the general distance runners, and the changes of MPF, FC, and IEMG were obtained during the limb flexion, extension, and special exercise movements of high-level distance runners. When the FC was 100Hz, the MPF values of high-level distance runners were 64MV2/Hz, while the MPF values of average-distance runners were 45 MV2/Hz. When the muscle strength reached 50%, the IEMG values of rectus abdominis, biceps femoris, and gastrocnemius were 52%, 45 and 56%, respectively, in high-level distance runners, while the IEMG values of average distance runners were 47%, 42%, and 50%, respectively and 50%, respectively. Through the data analysis, the high-level long-distance runners could maintain a higher exercise state and perform at a stable level despite the gradual muscle fatigue, their muscle strength and contraction ability were stronger, and their explosive muscle power and potential were greater than the average long-distance runners.

No Deficits in Functional Outcomes of the Contralateral Limb Are Seen When the Hamstring Is Harvested for Augmentation of Small Diameter Ipsilateral Hamstring Autograft

To evaluate clinical outcomes of the contralateral, nonoperative limb in patients undergoing contralateral hamstring (HS) autograft harvest compared with patients undergoing ipsilateral HS autograft harvest alone. This study included 96 patients who underwent isolated anterior cruciate ligament reconstruction (ACLR) using 4-stranded HS autograft (n= 85) or 4-stranded HS autograft augmented with contralateral HS (n= 13) due to inclusion of ipsilateral graft diameter <8 mm. Isokinetic flexion and extension strength and dynamic performance of the ipsilateral and contralateral limbs and limb symmetry index (LSI) were evaluated at 6 months' postoperatively. Rates of contralateral native ACL tear at minimum 2 years also were compared. For all comparisons, P < .05 was considered statistically significant. Normalized isokinetic knee flexion and extension strength of the contralateral limb did not differ between cohorts (P= .34; P= .21, respectively). LSI for knee extension peak torque and knee flexion peak torque did not differ between cohorts (P= .44; P= .67, respectively). No difference in LSI was seen for any dynamic performance testing (single leg hop, P= .97; triple leg hop, P= .14; 6-m timed hop, P= .99). No difference was observed in International Knee Documentation Committee (P= .99) or Knee Injury and Osteoarthritis Outcome Score subscale measures (P= .39-.86). No difference in rates of contralateral knee native ACL tears were seen between cohorts (HS autograft+ contralateral HS augmentation, n= 2, 15.4%; HS autograft, n= 7, 8.4%; P= .26). In this study, at the time of return to sport, we found no differences in contralateral limb functional performance or limb symmetry measurements between patients undergoing contralateral HS autograft harvest for augmentation of smaller (<8 mm) diameter HS autografts harvested from the injured extremity. Level III, retrospective cohort study.

A comparative study of robusticity indices of long bones among hunter-gatherers and early agro-pastoral groups of India.

Diaphyseal robusticity and cross-sectional shapes of the bone tissues are influenced by mechanical loading history. It changes according to work demand on the body. It is the objective of this study to identify the shifts in the modes of subsistence, activities and mobility patterns through the comparison of the shape and strength of bone diaphyses among the Mesolithic, Chalcolithic and Harappan populations of India. For the analysis, 7 sites including 2 from Mesolithic (8000-4000 bc), 2 from Chalcolithic (2000-700 bc) and 3 from Harappan (3500-1800 bc) contexts are considered. The ratio obtained from the maximum length of the bones to their girth (at 50% or 35% from the distal end) and that from anterior-posterior and medio-lateral diameters were calculated (following Martin and Saller codes, 1957) to understand certain functional adaptations and stress markers on preserved long bones. Independent-sample T-tests and ANOVA were applied to detect mean differences of statistical significance within and between cultures. The robusticity indices obtained from the humeri increase from the hunting-gathering phase (M/F; 19.39/18.45) to the Chalcolithic phase (M/F; 21.99/19.39) showing a slight drop in the Harappan phase (M/F; 18.58/18.37). The right humeri of Mesolithic females show a directional asymmetry of length (4.08%-5.13%) while that in males reach up to 26.09% indicating right-dominant lateralization. In the Harappan phase, females show a greater value for the right ranging from 0.31% to 3.07%. The femoral robusticity of females increases from 11.42 in hunting-gathering societies to 13.28 in Harappan times while mid-shaft of the Mesolithic population clearly shows greater loading along the anterior-posterior (A-P) plane as the index in most cases exceeds 100. There are significant differences among males and females within each group in terms of the indices but significant differences could be discerned between the Mesolithic, Chalcolithic and Harappan populations in case of tibiae, radii and ulnae only. The occupation patterns certainly changed as humans became a food-producer from a hunter-gatherer. Occupations involving the extensive flexion and extension of upper limbs in the Chalcolithic period increase particularly in the Harappan phase. Sedentism gave rise to roundness of the femur and reduced the magnitude of lateralization. While equal level of mobility can be traced in case of both the sexes before the advent of agriculture, this distinction increases between the males and females in the agro-pastoral phases.

Initial strategy of an assistive technology for rehabilitation and monitoring of elderly patients

This article presents an initial assistive technology strategy for the rehabilitation and monitoring of elderly patients, focused on lower limb muscle recovery, from a condition of low gait stability to recovery without the use of crutches. The project is in progress, and its first module, the recovery one, measures the flexion and extension of the lower limbs in degrees and sends the data to a database for analysis by the physiotherapist. The second module consists of the design of support for a telephone integrated to the crutch, to facilitate the integration with existing applications, also containing an embedded system for integration with the first module. When the patient is already on crutches, the cell phone and an embedded system coupled to the patient are used, which send signals in case the patient falls. The results are still partial and from isolated parts of the project, so that, after the completion of the modules, it will be possible to integrate and quantitatively analyze the results. The voltage source showed a current output that was maintained despite the load and without a voltage drop. The movement monitoring system through the camera recognized the knee flexion movement. The initial architecture of the system managed to include a system involving computer graphics, and screens that concern the human-computer interface. The crutch and the telephone support underwent usability tests that proved basic mechanical resistance to not present elementary difficulties in sustaining a person and a cellular device.

Active and passive mechanics for rugose terrain traversal in centipedes.

Centipedes coordinate body and limb flexion to generate propulsion. On flat, solid surfaces, the limb-stepping patterns can be characterized according to the direction in which limb-aggregates propagate, opposite to (retrograde) or with the direction of motion (direct). It is unknown how limb and body dynamics are modified in terrain with terradynamic complexity more representative of these animal's natural heterogeneous environments. Here, we investigated how centipedes that use retrograde and direct limb-stepping patterns, Scolopendra polymorpha and Scolopocryptops sexspinosus, respectively, coordinate their body and limbs to navigate laboratory environments which present footstep challenges and terrain rugosity. We recorded the kinematics and measured the locomotive performance of these animals traversing two rugose terrains with randomly distributed step heights and compared the kinematics with those on a flat frictional surface. Scolopendra polymorpha exhibited similar body and limb dynamics across all terrains and a decrease in speed with increased terrain rugosity. Unexpectedly, when placed in a rugose terrain, S. sexspinosus changed the direction of the limb-stepping pattern from direct to retrograde. Further, for both species, traversal of these rugose terrains was facilitated by hypothesized passive mechanics: upon horizontal collision of a limb with a block, the limb bent and later continued the stepping pattern. Although centipedes have many degrees of freedom, our results suggest these animals negotiate limb-substrate interactions and navigate complex terrains leveraging the innate flexibility of their limbs to simplify control.

Surgical correction of polymelia in the perineal region of a 2-day-old indigenous bovine calf: a case report from Bangladesh

BackgroundPolymelia is an occasional and congenital malformation in bovine calves, characterized by the presence of single or multiple accessory limb(s) at various body regions, which are often called the supernumerary limb(s). One of these defects is known as pygomelia, where the additional limb is attached to the pelvis within the perineal region. This study describes such a case along with surgical management.Case presentationA 2-day-old indigenous bovine female calf of 22.7 kg BW was presented with an additional and non-functional fifth limb at the perineal region. The ectopic fifth limb was smaller in size than the other four normal limbs and was in a flexible hanging position. Other than this, the animal was apparently normal with a short and contracted tail. Clinical examinations involving the extension and flexion of the abnormal limb revealed no deep bony attachment/articulation with the pelvic girdle or the caudal spine. The curled tail having an S-shaped base indicated the skeletal defects in the caudal spine. Electrosurgery was performed under deep sedation with regional as well as local anesthesia, which exposed that the limb was internally seated into deep gluteal muscle layers with the attachments of fibrous connective tissues and cartilage to its proximal bony head and located partially to the left lateroventral extremity of the perineum without any direct involvement in the bony pelvis. Surgical excision was done to remove the supernumerary limb, and the wound was closed routinely. Postoperatively, the animal was provided with supportive medications for early healing and recovery. After 2 weeks of surgery, the calf completely recovered without any complications. The contracted tail and spine were left unaffected as no initial surgical maneuver was done due to the early age of the calf and would be considered for further long-term treatment options upon the growth and development with age.ConclusionsPygomelia of bovine calves is one of the rare congenital defects that can be found along with other developmental anomalies. However, this defect can be successfully corrected by surgical approaches following intensive postoperative care and management.