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An increase in plantar pressure and skin temperature is commonly associated with an increased risk of diabetic foot ulcers. However, the effect of insoles in reducing plantar temperature has not been commonly studied. The aim was to assess the effect of walking in insoles with different features on plantar temperature. Twenty-six (F/M:18/8) participants-13 with diabetes and 13 healthy, aged 55.67 ± 9.58 years-participated in this study. Skin temperature at seven plantar regions was measured using a thermal camera and reported as the difference between the temperature after walking with an insole for 20 m versus the baseline temperature. The mixed analyses of variance indicated substantial main effects for the Insole Condition, for both the right [Wilks' Lambda = 0.790, F(14, 492) = 4.393, p < 0.01, partial eta squared = 0.111] and left feet [Wilks' Lambda = 0.890, F(14, 492) = 2.103, p < 0.011, partial eta squared = 0.056]. The 2.5 mm-tall dimple insole was shown to be significantly more effective at reducing the temperature in the hallux and third met head regions compared to the 4 mm-tall dimple insole. The insoles showed to be significantly more effective in the diabetes group versus the healthy group, with large effect size for the right [Wilks' Lambda = 0.662, F(14, 492) = 8.037, p < 0.000, Partial eta-squared = 0.186] and left feet [Wilks' Lambda = 0.739, F(14, 492) = 5.727, p < 0.000, Partial eta-squared = 0.140]. This can have important practical implications for designing insoles with a view to decrease foot complications in people with diabetes.

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AIMS/INTRODUCTION: This study aimed to assess if patients can be divided into different strata, and to explore if these correspond to the risk of diabetic foot complications. MATERIALS AND METHODS: A set of 28 demographic, vascular, neurological and biomechanical measures from 2,284 (1,310 men, 974 women) patients were included in this study. A two-step cluster analysis technique  was utilised to divide the patients into groups, each with similar characteristics. RESULTS: Only two distinct groups: group 1 (n = 1,199; 669 men, 530 women) and group 2 (n = 1,072; 636 men, 436 women) were identified. From continuous variables, the most important predictors of grouping were: ankle vibration perception threshold (16.9 ± 4.1 V vs 31.9 ± 7.4 V); hallux vibration perception threshold (16.1 ± 4.7 V vs 33.1 ± 7.9 V); knee vibration perception threshold (18.2 ± 5.1 V vs 30.1 ± 6.5 V); average temperature sensation threshold to cold (29.2 ± 1.1°C vs 26.7 ± 0.7°C) and hot (35.4 ± 1.8°C vs 39.5 ± 1.0°C) stimuli, and average temperature tolerance threshold to hot stimuli at the foot (43.4 ± 0.9°C vs 46.6 ± 1.3°C). From categorical variables, only impaired sensation to touch was found to have importance at the highest levels: 87.4% of those with normal sensation were in group 1; whereas group 2 comprised 95.1%, 99.3% and 90.5% of those with decreased, highly-decreased and absent sensation to touch, respectively. In addition, neuropathy (monofilament) was a moderately important predictor (importance level 0.52) of grouping with 26.2% of participants with neuropathy in group 1 versus 73.5% of participants with neuropathy in group 2. Ulceration during follow up was almost fivefold higher in group 2 versus group 1. CONCLUSIONS: Impaired sensations to temperature, vibration and touch were shown to be the strongest factors in stratifying patients into two groups with one group having almost 5-fold risk of future foot ulceration compared to the other.

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This systematic review aimed to synthesize and summarize the use of simulation of radiotherapy pathways. The objective was to establish the suitability of those simulations in modeling the potential introduction of processes and technologies to speed up radiotherapy pathways. A systematic literature search was carried out using PubMed and Scopus databases to evaluate the use of simulation in radiotherapy pathways. Full journal articles and conference proceedings were considered, and the search was limited to the English language only. To be eligible for inclusion, articles had to model multiple sequential processes in the radiotherapy pathway concurrently to demonstrate the suitability of simulation modeling in typical pathways. Papers solely modeling scheduling, capacity, or queuing strategies were excluded. In total, 151 potential studies were identified and screened to find 18 relevant studies in October 2022. Studies showed that various pathways could be modeled, including the entire pathway from referral to end of treatment or the constituent phases such as pre-treatment, treatment, or other subcomponents. The data required to generate models varied from study to study, but at least 3 months of data were needed. This review demonstrates that modeling and simulation of radiotherapy pathways are feasible and that model output matches real-world systems. Validated models give researchers confidence to modify models with potential workflow enhancements to assess their potential effect on real-world systems. It is recommended that researchers follow best practice guidelines when building models to ensure that they are fit for purpose and to enable decision makers to have confidence in their results.

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This study aimed to investigate the efficacy of using routinely collected clinical data in predicting the risk of diabetic foot ulcer (DFU). The first objective was to develop a prognostic model based on the most important risk factors objectively selected from a set of 39 clinical measures. The second objective was to compare the prediction accuracy of the developed model against that of a model based on only the 3 risk factors that were suggested in the systematic review and meta-analyses study (PODUS). In a cohort study, a set of 12 continuous and 27 categorical data from patients (n = 203 M/F:99/104) who attended a specialised diabetic foot clinic were collected at baseline. These patients were then followed-up for 24 months during which 24 (M/F:17/7) patients had DFU. Multivariate logistic regression was used to develop a prognostic model using the identified risk factors that achieved p < 0.2 based on univariate logistic regression. The final prognostic model included 4 risk factors (Adjusted-OR [95% CI]; p) in total. Impaired sensation (116.082 [12.06-1117.287]; p = 0.000) and presence of callus (6.257 [1.312-29.836]; p = 0.021) were significant (p < 0.05), while having dry skin (5.497 [0.866-34.89]; p = 0.071) and Onychomycosis (6.386 [0.856-47.670]; p = 0.071) that stayed in the model were not significant. The accuracy of the model with these 4 risk factors was 92.3%, where sensitivity and specificity were 78.9%, and 94.0% respectively. The 78.9% sensitivity of our prognostic 4-risk factor model was superior to the 50% sensitivity that was achieved when the three risk factors proposed by PODUS were used. Also our proposed model based on the above 4 risk factors showed to predict the DFU with higher overall prognostic accuracy. These findings have implications for developing prognostic models and clinical prediction rules in specific patient populations to more accurately predict DFU.

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Free-swimming performance depends strongly on the ability to develop propulsive force and minimise resistive drag. Therefore, estimating resistive drag (passive or active) may be important to understand how free-swimming performance can be improved. The purpose of this narrative overview was to describe and discuss experimental methods of measuring or estimating active and passive drag relevant to competitive swimming. Studies were identified using a mixed-model approach comprising a search of SCOPUS and Web of Science data bases, follow-up of relevant studies cited in manuscripts from the primary search, and additional studies identified by the co-authors based on their specific areas of fluid dynamics expertise. The utility and limitations of active and passive drag methods were critically discussed with reference to primary research domains in this field, 'swimmer morphology' and 'technique analysis'. This overview and the subsequent discussions provide implications for researchers when selecting an appropriate method to measure resistive forces (active or passive) relevant to improving performance in free-swimming.

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Objective. The mechanical behaviour of soft tissue is influenced by its elastic and viscous characteristics. Therefore, the aim of this study was to develop a validated method to characterise the viscoelastic properties of soft tissues based on ultrasound elastography data.Approach. Plantar soft tissue was chosen as the tissue of interest, and gelatine-phantoms replicating its mechanical properties were manufactured for validation of the protocol. Both plantar soft tissue and the phantom were scanned using Reverberant shear wave ultrasound (US) elastography at 400-600 Hz. Shear wave speed was estimated using the US particle velocity data. The viscoelastic parameters were extracted by fitting the Young's modulus as a function of frequency derived from the constitutive equations of the eight rheological models (four classic and their fractional-derivative versions) to the shear wave dispersion data. Furthermore, stress-time functions derived from the eight rheological models were fitted to the phantom stress-relaxation data.Main results. The viscoelastic parameters estimated using elastography data based on the fractional-derivative (FD) models, compared to the classic models, were closer to those quantified using the mechanical test. In addition, the FD-Maxwell and FD-Kelvin-Voigt models showed to more effectively replicate the viscoelastic behaviour of the plantar soft tissue with minimum number of model parameters (R2= 0.72 for both models) . Hence the FD-KV and FD-Maxwell models can more effectively quantify the viscoelastic characteristics of the soft tissue compared to other models.Significance. In this study, a method for mechanical characterisation of the viscoelastic properties of soft tissue in ultrasound elastography was developed and fully validated. An investigation into the most valid rheological model and its applications in plantar soft tissue assessment were also presented. This proposed approach for the characterisation of viscous and elastic mechanical properties of soft tissue has implications in assessing the soft tissue function where those can be used as markers for diagnosis or prognosis of tissue status.

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BACKGROUND: Extracorporeal Membrane Oxygenation (ECMO) therapy for respiratory failure is an increasingly popular modality of support. Patient selection is an important aspect of outcome success. This review assesses the efficacy of the popular prognostic tools Respiratory ECMO Survival Prediction Score (RESP) and Predicting Death for Severe ARDS on VV-ECMO score (PRESERVE) for ECMO patient selection. METHODS: A literature search was performed. Six publications were found to match the specified selection criteria. These publications were assessed and compared using the area under the receiver operating characteristic (AUROC) curve statistical method to ascertain the discriminatory ability of the models to predict treatment outcome. RESULTS: Six articles were included in this review from 306 screened, of which all were retrospective cohort studies. Data was generated over a period of 3-9 years from 13 referring hospitals. Studies consisted of 467 male and 221 female (30 unknown) participants in total with a high heterogeneity. The PRESERVE prognostic model was found to have a higher AUROC score than the RESP model, however both models were found to be sub-optimal in their discriminatory ability. A high chance of bias was seen across all included studies. CONCLUSION: It was the findings of this review, indicated by analysis using the AUROC measures, that the prognostic model PRESERVE performed better than RESP for predicting post ECMO therapy outcomes, for patients presenting with Acute Respiratory Distress Syndrome within their respective validated time frames, i.e., RESP at Intensive care unit (ICU) discharge and PRESERVE at 6 months post ICU discharge. However, It was recognized that comparator groups were small thereby introducing bias into the study. Further prospective, randomized studies would be necessary to effectively assess the utility of these predictive survival scores.

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The knowledge of the biomechanical properties of tissues is useful for different applications such as disease diagnosis and treatment monitoring. Reverberant Shear Wave Elastography (RSWE) is an approach that has reduced the restrictions on wave generation to characterize the shear wave velocity over a range of frequencies. This approach is based on the generation of a reverberant field that is generated by the reflections of waves from inhomogeneities and tissue boundaries that exist in the tissue. The Kelvin-Voigt Fractional Derivative model is commonly used to characterize elasticity and viscosity of soft tissue when using shear wave ultrasound elatography. These viscoelastic characteristics can be then validated using mechanical measurements (MM) such as stress relaxation. During RSWE acquisition, the effect of interface pressure, induced by pushing the probe on the skin through the gel pad, on the viscous and elastic characteristics of tissue can be investigated. However, the effect of interface pressure on the validity of the extracted viscous and elastic characteristics was not investigated before. Therefore, the purpose of this study was to compare the estimation of the viscoelastic parameters at different thickness of gel pad against the viscoelastic characteristics obtained from MM. The experiments were conducted in a tissue-mimicking phantom. The results confirm that the relaxed elastic constant (µ0) can be depreciated. In addition, a higher congruence was found in the viscous parameter (ηα) estimated at 6 and 7 mm. On the other hand, a difference in the order of fractional derivative (α) was found.

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To support the effective use of Shore hardness (SH) in research and clinical practice this study investigates whether SH should be interpreted as a measurement of skin or of bulk tissue biomechanics. A 3D finite element model of the heel and a validated model of a Shore-00 durometer were used to simulate testing for different combinations of stiffness and thickness in the skin and subcutaneous tissue. The results of this numerical analysis showed that SH is significantly more sensitive to changes in skin thickness, relatively to subcutaneous tissue, but equally sensitive to changes in the stiffness of either tissue. Indicatively, 25% reduction in skin thickness (0.3 mm thickness change) or in subcutaneous tissue thickness (5.9 mm thickness change), reduced SH by 7% or increased SH by 2% respectively. At the same time, 25% reduction in skin stiffness (10.1 MPa change in initial shear modulus) or of subcutaneous tissue (4.1 MPa change in initial shear modulus) led to 11% or 8% reduction in SH respectively. In the literature, SH is commonly used to study skin biomechanics. However, this analysis indicates that SH quantifies the deformability of bulk tissue, not of skin. Measurements of skin thickness are also necessary for the correct interpretation of SH.

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INTRODUCTION: This prospective cohort study aimed to identify the characteristics of patients with diabetic foot ulcer who are at higher risk of amputation and at increased risk of death. METHODS: About 103(M/F:60/43) participants, with active foot ulcer at baseline, participated in this study and followed for 22 years till death or lost to follow-up. Ten clinical measures were collected at baseline. During the follow-up of 4.2 ± 5.4 years, 22(M/F:14/8) participants had an amputation and 50(M/F:32/18) participants passed away during 5.5 ± 5.8 years follow-up period. RESULTS: Cox Proportional Hazard regression (HR[95%CI]) indicated neuropathy (6.415[1.119-36.778]); peripheral arterial disease (PAD) (9.741[1.932- 49.109]); current smoking (16.148[1.658-157.308]); diabetes type- 1 (3.228[1.151-9.048]) and longer delay attending appointment after ulcer (1.013[1.003-1.023]) were significantly (p < .05) associated with increased risk of amputation. In addition, death was significantly associated with the risk of amputation (3.458[1.243-9.621]). Three parameters (HR[95%CI]) including neuropathy (3.058[1.297-7.210]); PAD (5.069[2.113-12.160]); amputation history (3.689[1.306-10.423]) and retinopathy (2.389[1.227-4.653]) were all significantly associated with increased risk of death. Kaplan-Meier survival analyses indicates that the time to amputation in years for participants who eventually died was significantly shorter (11.122 ± 1.507) vs those who stayed alive (15.427 ± 1.370). CONCLUSION: Neuropathy and PAD were the only two characteristics that increased both the risk of amputation and death. Amputation showed to contribute to an increased risk of death and those participants who eventually died had a higher risk of amputation. Delay in attending appointments after ulceration is shown to increase the risk of amputation. In addition, the participants with PAD showed a significantly shorter time to both amputation and death while neuropathy was only associated with decreased time to death. Amputation history and death during follow-up decrease the time to death and amputation respectively.

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The primary objective of this study was to develop a method that allows accurate quantification of plantar soft tissue stiffness distribution and homogeneity. The secondary aim of this study was to investigate if the differences in soft tissue stiffness distribution and homogeneity can be detected between ulcerated and non-ulcerated foot. Novel measures of individual pixel stiffness, named as quantitative strainability (QS) and relative strainability (RS) were developed. Strain Elastography data obtained from 39 (nine with active diabetic foot ulcers) patients with diabetic neuropathy. The patients with active diabetic foot ulcer had wound in parts of the foot other than the first metatarsal head and the heel where the elastography measures were conducted. RS was used to measure changes and gradients in the stiffness distribution of plantar soft tissues in participants with and without active diabetic foot ulcer. The plantar soft tissue homogeneity in superior-inferior direction in the left forefoot was found to be significantly (p < 0.05) higher in ulcerated group compared to non-ulcerated group. The assessment of homogeneity showed potentials to further explain the nature of the change in tissue that can increase internal stress. This can have implications in assessing the vulnerability to plantar soft tissue damage and ulceration in diabetes.

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Different antioxidants including coenzyme Q10 (CoQ10) have been tried to treat idiopathic male infertility (IMI) with variable results. Therefore, this study aimed to determine the clinical and biochemical predictors of pregnancy outcome and time to pregnancy (TTP) in infertile men with idiopathic oligoasthenospermia (OA) pre- and post-CoQ10 therapy. This prospective controlled clinical study included 178 male patients with idiopathic OA and 84 fertile men (controls). Patients received 200 mg of oral CoQ10 once daily for 6 months. Demographics, semen parameters, seminal CoQ10 levels, reactive oxygen species (ROS) levels, total antioxidant capacity (TAC), catalase (CAT), glutathione peroxidase (GPx), sperm DNA fragmentation (SDF) and body mass index were measured and compared at baseline and after 6 months. All participants were followed up for another 18 months for pregnancy outcome and TTP. CoQ10 therapy for 6 months significantly improved semen parameters, antioxidant measures and reduced SDF. The pregnancy rate was 24.2% and TTP was 20.52 ± 6.72 months in patients as compared to 95.2% and 5.73 ± 6.65 months in fertile controls. After CoQ10 therapy, CoQ10 level, sperm concentration, motility and ROS were independent predictors of pregnancy outcome and CoQ10 level, male age, sperm concentration, motility, ROS and GPx were independent predictors of TTP in patients. In conclusion, CoQ10 therapy of 6 months is a potential treatment for men with idiopathic OA. CoQ10 level, male age, semen parameters, ROS and GPx could potentially be used as diagnostic biomarkers for male fertility and predictors for pregnancy outcome and TTP in these patients.

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INTRODUCTION: The purpose of this study was to investigate the association between the mechanical properties of plantar soft tissue and diabetes status. METHOD: 51 (M/F: 21/30) participants with prediabetes onset (fasting blood sugar [FBS] level > 100 mg/dL), age >18 years, and no lower limb amputation were recruited after ethical approval was granted from Pontificia Universidad Catolica del Peru ethical review board. Ultrasound reverberant shear wave elastography was used to assess the soft tissue stiffness at the 1st metatarsal head (MTH), 3rd MTH, and the heel at both feet. RESULTS: Spearman's rank-order correlation (rho) test indicated a significant (P < .05) positive correlations between FBS level and the plantar soft tissue shear wave speed at the 1st MTH: rho = 0.402 (@400 Hz), rho = 0.373 (@450 Hz), rho = 0.474 (@500 Hz), rho= 0.395 (@550 Hz), and rho = 0.326 (@600 Hz) in the left foot and rho = 0.364 (@450 Hz) in the right foot. Mann-Whitney U test indicated a significantly (P < .05) higher shear wave speed in the plantar soft tissue with the following effect sizes (r) at the 1st MTH of the left foot at all tested frequencies: r = 0.297 (@450 Hz), r = 0.345 (@500 Hz), r = 0.322 (@550 Hz), and r = 0.275 (@600 Hz), and at the 1st MTH of right foot r = 0.286 (@400 Hz) in diabetes as compared with the age and body mass index matched prediabetes group. CONCLUSION: An association between fasting blood sugar level and the stiffness of the plantar soft tissue with higher values of shear wave speed in diabetes versus prediabetes group was observed. This indicated that the proposed approach can improve the assessment of the severity of diabetic foot complications with potential implications in patient stratification.

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Plantar soft tissue stiffness provides relevant information on biomechanical characteristics of the foot. Therefore, appropriate monitoring of foot elasticity could be useful for diagnosis, treatment or health care of people with complex pathologies such as a diabetic foot. In this work, the reliability of reverberant shear wave elastography (RSWE) applied to plantar soft tissue was investigated. Shear wave speed (SWS) measurements were estimated at the plantar soft tissue at the first metatarsal head, the third metatarsal head and the heel from both feet in five healthy volunteers. Experiments were repeated for a test-retest analysis with and without the use of gel pad using a mechanical excitation frequency range between 400 and 600 Hz. Statistical analysis was performed to evaluate the reliability of the SWS estimations. In addition, the results were compared against those obtained with a commercially available shear wave-based elastography technique, supersonic imaging (SSI). The results indicate a low coefficient of variation for test-retest experiments with gel pad (median: 5.59%) and without gel pad (median: 5.83%). Additionally, the values of the SWS measurements increase at higher frequencies (median values: 2.11 m/s at 400 Hz, 2.16 m/s at 450 Hz, 2.24 m/s at 500 Hz, 2.21 m/s at 550 Hz and 2.31 m/s at 600 Hz), consistent with previous reports at lower frequencies. The SWSs at the plantar soft tissue at the first metatarsal head, third metatarsal head and heel were found be significantly (p<0.05) different, with median values of 2.42, 2.16 and 2.03 m/s, respectively which indicates the ability of the method to differentiate between shear wave speeds at different anatomical locations. The results indicated better elastographic signal-to-noise ratios with RSWE compared to SSI because of the artifacts presented in the SWS generation. These preliminary results indicate that the RSWE approach can be used to estimate the plantar soft tissue elasticity, which may have great potential to better evaluate changes in biomechanical characteristics of the foot.

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Diabetic foot syndrome is one of the most costly complications of diabetes. Damage to the soft tissue structure is one of the primary causes of diabetic foot ulcers and most of the current literature focuses on factors such as neuropathy and excessive load. Although the role of blood supply has been reported in the context of macro-circulation, soft tissue damage and its healing in the context of skin microcirculation have not been adequately investigated. Previous research suggested that certain microcirculatory responses protect the skin and their impairment may contribute to increased risk for occlusive and ischemic injuries to the foot. The purpose of this narrative review was to explore and establish the possible link between impairment in skin perfusion and the chain of events that leads to ulceration, considering the interaction with other more established ulceration factors. This review highlights some of the key skin microcirculatory functions in response to various stimuli. The microcirculatory responses observed in the form of altered skin blood flow are divided into three categories based on the type of stimuli including occlusion, pressure and temperature. Studies on the three categories were reviewed including: the microcirculatory response to occlusive ischemia or Post-Occlusive Reactive Hyperaemia (PORH); the microcirculatory response to locally applied pressure such as Pressure-Induced Vasodilation (PIV); and the interplay between microcirculation and skin temperature and the microcirculatory responses to thermal stimuli such as reduced/increased blood flow due to cooling/heating. This review highlights how microcirculatory responses protect the skin and the plantar soft tissues and their plausible dysfunction in people with diabetes. Whilst discussing the link between impairment in skin perfusion as a result of altered microcirculatory response, the review describes the chain of events that leads to ulceration. A thorough understanding of the microcirculatory function and its impaired reactive mechanisms is provided, which allows an understanding of the interaction between functional disturbances of microcirculation and other more established factors for foot ulceration.

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Foot temperature during activities of daily living affects the human performance and well-being. Footwear thermal characteristics affect the foot temperature inside the shoe during activities of daily living. The temperate at the sole of the foot (plantar temperature) is influenced by different thermal properties such as heat capacity, heat diffusivity, and thermal conductivity of the shoe sole in addition to its mechanical properties. Hence the purpose of this study was to propose a method to allow investigating the effect of footwear thermal characteristics on the foot temperature during activities of daily living, like walking or jogging. The transient heat transfer between the foot and the ground was studied to drive the governing equation for heat transfer modelling in footwear and to predict foot sole temperature during walking, and jogging. Different thermo-mechanical properties of shoe sole, as well as geometrical parameters, were investigated. The proposed model showed to be able to adequately predict the plantar temperature at the ball of the foot when compared to the results from experimental measurements. Finally, using the proposed method, the thermal behaviour of two different shoes with two different sole materials EVA08 and EVA12 were compared. It was shown that heat capacity as compared to the thermal conductivity of the shoe sole is more effective in reducing the plantar temperature increase in short term. The proposed method proved to be able to accurately predict the thermal behaviour of shoes and can provide a tool to predict footwear thermal comfort.

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Curvatures of the body can disrupt fluid flow and affect hydrodynamic resistance. The purpose of this study was to evaluate the effect of a feedback intervention on glide performance and torso morphology. Eleven male and female national swimmers performed glides before and after augmented feedback. Feedback consisted of self-modelling visual feedback and verbal cuing, to manipulate body curvatures that affect hydrodynamic resistance. Two-dimensional landmark position data (knee, hip and shoulder) were used to enable computation of glide factor and glide coefficient as indicators of glide efficiency; posture (trunk incline and hip angle); and performance (horizontal velocity). Underwater images of the swimmers were manually traced to derive transverse and sagittal diameters, cross-sectional areas, and continuous form outlines (anterior and posterior) of the torso. Maximum rate of change in cross-sectional area and form gradient progressing caudally, were calculated for torso segments: shoulder-chest, chest-waist, waist-hip. Mean velocity, glide factor and glide coefficient values significantly (p< 0.001) improved due to the intervention, with large effect size (d) changes 0.880 (p= 0.015), 2.297 and 1.605, respectively. Significant changes to form gradients were related to reductions in lumbar lordosis and chest convexity. The study provides practical cuing phrases for coaches and swimmers to improve glide efficiency and performance.

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The aim of this study was to compare the spine-pelvis coordination and coordination variability (CV) during rowing in elite rowers with and without chronic low back pain (CLBP). Fourteen professional rowers (6 healthy and 8 with CLBP) participated in this study. 3D kinematic of upper trunk (UT), lower trunk (LT), lower back (LB), and pelvis segments during ergometer rowing at 70% and 100% of peak power were captured. The adjacent segments' coordination and CV were calculated using modified vector coding method. The results showed that segments' range of motion increased in both groups with increasing intensity, especially in CLBP rowers. CLBP rowers showed significantly lower: LT dominancy in LT/LB coordination at both intensities; anti-phase pattern in LB/Pelvis coordination at 100% intensity; UT/LT CV in early recovery, and significantly higher LB/Pelvis CV in final recovery and catch position (p < 0.05). Moreover, both groups showed significantly lower UT dominancy for UT/LT coordination in sagittal plane; higher anti-phase pattern in frontal plane; lower UT/LT CV in sagittal plane, lower LT/LB CV in sagittal and transverse plane, lower LB/Pelvis CV in frontal plane in trunk preparation phase, and a lower UT/LT CV in frontal plane for acceleration phase at 100% versus 70% intensity. In conclusion rowers with CLBP cannot adapt their coordination pattern and its variability with increase in intensity, and the movement in the kinematic chain from pelvis to UT stops in spine-pelvic junction. These findings have practical implications in designing coaching and rehabilitation strategies to facilitate performance and prevent injuries.

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Assessing skin perfusion is an established and reliable method to study impaired lower limb blood flow. Laser Speckle Contrast Analysis (LASCA) has been identified as the current gold standard to measure skin perfusion. Imaging photoplethysmography (iPPG) is a new low-cost imaging technique to assess perfusion. However, it is unclear how results obtained from this technique compare against that of LASCA at plantar skin. Therefore, the aim of this study was to investigate the association between the skin perfusion at the plantar surface of the foot using iPPG and LASCA. Perfusion at six plantar locations (Hallux, 1st 3rd 5th metatarsal heads, midfoot, heel) was simultaneously measured using LASCA and iPPG in 20 healthy participants. Skin thickness and skin temperature were also collected at the same plantar locations. Spearman's rank tests showed significant associations with medium strength between the perfusion values measured with LASCA and iPPG for most tested sites. No improvement in the relationship between iPPG and LASCA data was observed when controlling for either skin thickness or skin temperature. Skin perfusion values obtained using iPPG were found to be significantly associated with the corresponding values obtained using the gold standard LASCA device. Additionally, the measurement of perfusion using iPPG is shown to be robust.

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OBJECTIVES: Cutaneous microcirculatory impairments are associated with skin injury to the foot. Post-Occlusive reactive hyperemia (PORH) is one of the quick and easy methods to assess microcirculatory function. However, there are variations in the protocols currently used. Hence, this study aimed to systematically investigate the reproducibility of PORH protocols with minimal occlusion time in the foot. METHODS: Post-Occlusive reactive hyperemia was measured using 12 different protocols (three occlusion times, two occlusion sites and with or without temperature control) in 25 healthy adults. Each of the 12 different protocols was repeated three times, and the intraclass correlation coefficient (ICC) was calculated. RESULTS: Intraclass correlation coefficient showed that that ankle level occlusion produced moderate to excellent reproducibility for most PORH measures. In the right foot, 30- and 60-s ankle level occlusion without temperature control showed ICC of >0.40 for all parameters except the area of hyperemia (ICC = -0.36) and biological zero to peak flow percent change (ICC = -0.46). In the left foot, 30-s ankle level occlusion without temperature control showed ICC of >0.40 for all parameters except time to latency (ICC = 0.29), after hyperemia (ICC = 0.37), and max (ICC = -0.01), and area of hyperemia (ICC = -0.36). But the 60-s protocol showed ICC > 0.40 for all except time to max (ICC = 0.38). In the hallux protocols, all three 10-, 30-, and 60-s protocols without temperature control showed moderate to excellent reproducibility (ICC > 0.40). In most cases, the temporal and area under the perfusion-time curve parameters showed poor reproducibility. CONCLUSION: Post-Occlusive reactive hyperemia can be tested efficiently with a minimal occlusion time of 10 s with hallux occlusion and 30 s with ankle occlusion in the foot. This can suggest that microcirculatory assessment is feasible in routine practice and can potentially be included for routine assessment of foot in people with diabetes.

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