Anteroposterior Direction Research Articles

Planning target volume margin in head and neck cancer patients undergoing radiation therapy: Estimations derived from own data and literature

Planning target volume (PTV) to deliver the desired dose to the clinical target volume (CTV) accounts for systematic (∑) and random (σ) errors during the planning and execution of intensity modulated radiation therapy (IMRT). As these errors vary at different departments, this study was conducted to determine the 3-dimensional PTV (PTV3D) margins for head and neck cancer (HNC) at our center. The same was also estimated from reported studies for a comparative assessment. A total of 77 patients with HNCs undergoing IMRT were included. Of these, 39 patients received radical RT and 38 received postoperative IMRT. An extended no action level protocol was implemented using on-board imaging. Shifts in the mediolateral (ML), anteroposterior (AP), and superoinferior (SI) directions of each patient were recorded for every fraction. PTV margins in each direction (ML, AP, SI) and PTV3D were calculated using van Herk's equation. Weighted PTV3D was also computed from the ∑ and σ errors in each direction published in the literature for HNC. Our patients were staged T2-4 (66/77) and N0 (39/77). In all, 2280 on-board images were acquired, and daily shifts in each direction were recorded. The PTV margins in the ML, AP, and SI directions were computed as 3.2 mm, 2.9 mm, and 2.6 mm, respectively. The PTV3D margin was estimated to be 6.5 mm. This compared well with the weighted median PTV3D of 7.2 mm (range: 3.2 to 9.9) computed from the 16 studies reported in the literature. To ensure ≥95% CTV dose coverage in 90% of HNC patients, PTV3D margin for our department was estimated as 6.5 mm. This agrees with the weighted median PTV3D margin of 7.2 mm computed from the 16 published studies in HNCs. Site-specific PTV3D margin estimations should be an integral component of the quality assurance protocol of each department to ensure adequate coverage of dose to CTV during IMRT.

Efficacy of drainage implants in combined cataract and glaucoma surgery

This study evaluates the hypotensive effect and visual function outcomes of combined surgery for complicated cataract and glaucoma using the mesh drain made of digeland the xenocollagen drain. Patients in Group 1 (n=43; 48.3%) underwent combined cataract and glaucoma surgery with implantation of the digel drainage implant, while patients in Group 2 (n=46; 51.7%) underwent an identical operation with the xenocollagen implant. Preoperative tonometric pressure was 27.2±1.7 and 27.3±1.9 mm Hg; best corrected visual acuity was 0.35±0.21 and 0.33±0.18, respectively. The following surgical technique was employed. At 3.0-4.0 mm from the limbus, an intrascleral tunnel was created using a 2.2 mm sclerotome through the conjunctiva in the anteroposterior direction, exiting into the anterior chamber. Capsulorhexis and phacoaspiration were performed. The scleral tunnel was widened to 3 mm, and the intraocular lens was implanted. Penetrating basal coloboma of the iris was formed. The deep flap of the scleral tunnel was dissected from the flat part of the ciliary body and removed. The digel implant was shaped into a T-configuration, while the xenocollagen implant was used without modification. Each drainage was implanted into the intrascleral tunnel (one end directed into the anterior chamber, the other exiting the scleral tunnel). The conjunctiva was sutured with 10/0 stitches, and the paracenteses were hydrated. Over a 24-month follow-up period, the tonometric intraocular pressure in Groups 1 and 2 was 18.8 and 18.5 mm Hg, respectively, and the best corrected visual acuity was 0.51 and 0.58. The use of both drainages in the proposed combined surgery for complicated cataract and glaucoma results in similarly stable hypotensive outcomes and high visual function.

The effect of using walking poles on the spatiotemporal gait parameters in patients who underwent surgery for hip fractures

Purpose This study aimed to investigate the differences in spatiotemporal gait parameters in patients who underwent surgery for hip fractures when using walking poles and T-canes. Methods This cross-sectional study enrolled eight patients who underwent surgery for a unilateral hip fracture (mean age, 79.0 ± 7.9 years) and 34 healthy individuals who had no symptoms (mean age, 32.1 ± 6.2 years). The outcome measures were the walking speed, trunk acceleration, and lateral lean angles of the trunk, shoulder, and pelvis during walking. The results were compared among the three types of walking aids, namely, a T-cane, double T-canes, and walking poles. Results Acceleration indices step symmetry in the vertical and anteroposterior directions in walking with walking poles were significantly larger than that in walking with a T-cane. These results were common in patients with fractures and healthy individuals. Conclusions Walking with walking poles might be a more symmetrical gait style than walking with a T-cane in patients who underwent surgery for hip fractures.

Pain alleviation improves balance control and muscular coordination of lower limbs in patients with chronic ankle instability during sinusoidal perturbations

BackgroundIt is well established that individuals with chronic ankle instability manifest deficits in balance control and muscle activation. Given the prevalence of pain as a prominent symptom in this population, there is a need for in-depth investigation of its role in contributing to these impairments. MethodsA Stewart platform was used to generate translational sinusoidal perturbations in the antero-posterior direction. Eighteen individuals with chronic ankle instability and concurrent ankle pain were recruited. They were instructed to assume a central stance on the support surface with open eyes both before and 30 min after local analgesia. Data of center of pressure and electromyography of the tibialis anterior and medial gastrocnemius were recorded. Statistical analysis was performed to make comparisons pre- and post-analgesia using two-tailed paired t-test for the continuous variables. FindingsPain intensity was significantly decreased after local anesthetic injections. Antero-posterior center of pressure parameters significantly decreased following the injection. Also, there was an increase in the regularity of the center of pressure pattern. The electromyographic pattern of the tibialis anterior and medial gastrocnemius exhibited various activation patterns. After pain alleviation, the characteristic electromyographic response of the tibialis anterior and medial gastrocnemius was reciprocal contraction and relaxation that corresponded with the sinusoidal pattern of the perturbations. InterpretationIndividuals who had chronic ankle instability and ankle pain demonstrated impaired balance control during sinusoidal perturbations. Mitigating pain improved their balance performance, evident in the center of pressure pattern and the coordination of lower limb muscles.

Influence of contrast administration side and communication with patient on motion artefact size on breast MRI

Magnetic resonance imaging is recognized as a useful modality in breast imaging. Motion is considered the most relevant cause of artefacts in breast MRI leading to degraded image quality or rendering studies non-diagnostic. The important reason for patient motion is contrast administration. Contrast administration may lead to discomfort, feeling of tingling and warmth, and pain in the arm contrast was administered to. The aim of our study was to determine the influence of contrast agent injection side and improve communication with patients on motion artifacts on subtraction reconstructions in order to prove that unexpected events may cause non-physiological movement resulting in motion artifacts, and that well-timed warning may decrease such artifacts. 146 patients with breast MRI from July 2019 to May 2020 were included. 71 of them were warned before the dynamic sequence started, and 75 of them didn't receive any warning for contrast application. The pectoral shift, in millimeters in the anteroposterior and lateral-lateral directions, was measured. Pectoral shift showed to be larger in unwarned patients when compared to warned ones with high significance (p=0.001) -no artifacts were observed in 361 warned, and 267 in unwarned women. Furthermore, artifacts were significantly larger on the side contralateral to contrast administration (median value of 2mm for the same side, and 1mm on the opposite side). In conclusion, our study showed that if patients knew the exact time of contrast application, the motion artifacts would be less pronounced; and that we should apply the contrast agent on the side opposite to the breast pathology is expected in.

Dynamic gait stability in children with and without Down syndrome during overground walking

BackgroundChallenging children with Down syndrome to walk fast and with external ankle load has demonstrated acute adjustments, such as increased step length and decreased step width, and improved joint stability. However, it is unknown to what extent these task constraints affect gait stability. Assessing dynamic gait stability through margin-of-stability not only quantifies adjustments related to balance control, but also informs safety considerations. MethodsTwenty-four children with and without Down syndrome participated in this study. Subjects walked overground at two speed conditions: self-selected (normal) and as fast as possible (fast); and two ankle load conditions: no load and ankle load of 2% body mass. We assessed margin-of-stability in the anteroposterior and mediolateral directions, separately, at three gait events of toe-off, mid-swing, and heel strike. FindingsChildren with Down syndrome walked with greater mediolateral margin-of-stability than typically developing children. Children with Down syndrome demonstrated less anteroposterior margin-of-stability than typically developing children only before heel-strike at normal speed but increased anteroposterior margin-of-stability at fast speed. The ankle load increased the mediolateral margin-of-stability in both groups but did not impact the anteroposterior margin-of-stability. In addition, children with Down syndrome took shorter and wider steps for more lateral placement of mediolateral margin-of-stability. InterpretationChildren with Down syndrome were capable of adjusting their margin-of-stability for fast walking and ankle-load conditions. However, children with Down syndrome walked with less mediolateral stability and anteroposterior mobility than typically developing children. Children with Down syndrome overcompensate the mediolateral foot placement to recapture their margin-of-stability and maintain gait stability.

Characterizing cardiac contractile motion for noninvasive radioablation of ventricular tachycardia

BackgroundRespiratory motion management strategies are used to minimize the effects of breathing on the precision of stereotactic ablative radiotherapy for ventricular tachycardia, but the extent of cardiac contractile motion of the human heart has not been systematically explored. ObjectiveWe aim to assess the magnitude of cardiac contractile motion between different directions and locations in the heart. MethodsPatients with intracardiac leads or valves who underwent 4D cardiac computed tomography (4DCT) prior to a catheter ablation procedure for atrial or ventricular arrhythmias at 2 medical centers were studied retrospectively. The displacement of transvenous right atrial appendage (RA), right ventricle (RV) ICD, coronary sinus (CS) lead tips and prosthetic cardiac devices across the cardiac cycle were measured in orthogonal 3D views on a maximal-intensity projection CT reconstruction. ResultsA total of 31 pre-ablation cardiac 4DCTs were analyzed. The LV lead tip had significantly greater motion compared to the RV lead in the anterior-posterior direction (6.0±2.2mm vs 3.8±1.7mm; p=0.01) and superior-inferior direction (4.4±2.9mm vs 3.5±2.0mm; p=0.049). The prosthetic aortic valves had the least movement of all fiducials, specifically compared to the RV lead tip in the left-right direction (3.2±1.2mm vs 6.1±3.8mm, p=0.04) and the LV lead tip in the antero-posterior direction (3.8±1.7mm vs 6.0±2.2mm, p=0.03). ConclusionThe degree of cardiac contractile motion varies significantly (1mm to 15.2 mm) across different locations in the heart. The effect of contractile motion on the precision of radiotherapy should be assessed on a patient-specific basis.

Immediate effects of local muscle vibration on static and dynamic balance control in individuals with chronic ankle instability

ObjectivesTo investigate the immediate effects of local muscle vibration (LMV) on static and dynamic balance control in individuals with and without chronic ankle instability (CAI). DesignQuasi-experimental study. SettingResearch laboratory. ParticipantsTwenty-six individuals with CAI and 26 healthy controls. Main outcome measuresCenter of pressure variables (mean total velocity and displacement in anteroposterior (AP) and mediolateral (ML) directions) during single-leg standing with eyes open and eyes closed and also reach distances in anterior (ANT), posteromedial (PM), and posterolateral (PL) directions of the modified star excursion balance test (MSEBT) were assessed before and after LMV. ResultsStatistical analyses showed a significant decrease in mean total velocity and displacement in AP direction from before to after LMV in eyes open condition for both individuals with CAI (p = 0.025, p = 0.041, respectively) and healthy controls (p = 0.001, p = 0.003, respectively). Similar results were observed in eyes closed condition for both individuals with CAI (p < 0.001, p < 0.001, respectively) and healthy controls (p = 0.040, p = 0.014, respectively). The results also showed increased reach distances in ANT (p < 0.001), PM (p < 0.001), and PL directions (p < 0.001) in all participants after LMV. ConclusionOur results suggest that LMV may be a useful tool in rehabilitation of static and dynamic balance deficits in individuals with CAI.

Morphological and Topographical Features of the Radial Recurrent Artery and Its Possible Clinical Significance

Objective: The anatomy of the radial recurrent artery (RRA) is very important for interventional procedures. The aim of this study was to investigate the morphological and topographic anatomy of the RRA. Methods: The study was conducted on 20 human cadavers (14 male and 6 female, 40 upper limbs). The RRA was classified into 4 groups as follows according to the observed origin: RRA originated from the radial artery (RA) (Type A), the root of the RA (Type B), the brachial artery (BA) (Type C), and the ulnar artery (UA). The relative positioning of the RRA in relation to the biceps brachii muscle tendon (TBB), in terms of the antero-posterior direction was determined. The vertical distance of the origin point of the RRA to the intercondylar line and the diameters of this artery were determined. Morphometric evaluation was performed with a digital caliper. The obtained data were analyzed using SPSS version 21.00 software. Results: The artery most commonly originated from the RA (Type A 47.5%, 19 extremities). This was followed by RA root (Type B 32.5%, 13 extremities), BA (Type C 17.5%, 7 extremities), and UA (Type D 2.5%, 1 extremity). The RRAs coursed anteriorly to the TBB in 38 extremities (95%) and passed behind the tendon in 2 extremities (5%). The vertical distance of the origin point of the RRA to the intercondylar line was meanly 32.20 ±6.86 mm. The diameter of the artery at its origin point was meanly 2.57 ± 0.58 mm and just after its first branch was meanly 2.05 ± 0.48 mm. Our study documents a rare morphological variation of the RRA originating from the UA (Type D). Conclusion: While many of our findings align with previous studies, this research presents novel anatomical findings and elucidates the superficial course and topographical positioning of the RRA to estimate its origin point.

Proof-of-concept of a robotic-driven photogrammetric scanner for intra-operative knee cartilage repair.

This work presents a proof-of-concept of a robotic-driven intra-operative scanner designed for knee cartilage lesion repair, part of a system for direct in vivo bioprinting. The proposed system is based on a photogrammetric pipeline, which reconstructs the cartilage and lesion surfaces from sets of photographs acquired by a robotic-handled endoscope, and produces 3D grafts for further printing path planning. A validation on a synthetic phantom is presented, showing that, despite the cartilage smooth and featureless surface, the current prototype can accurately reconstruct osteochondral lesions and their surroundings with mean error values of 0.199 ± 0.096mm but with noticeable concentration on areas with poor lighting or low photographic coverage. The system can also accurately generate grafts for bioprinting, although with a slight tendency to underestimate the actual lesion sizes, producing grafts with coverage errors of -12.2 ± 3.7, -7.9 ± 4.9, and -15.2 ± 3.4% for the medio-lateral, antero-posterior, and craneo-caudal directions, respectively. Improvements in lighting and acquisition for enhancing reconstruction accuracy are planned as future work, as well as integration into a complete bioprinting pipeline and validation with ex vivo phantoms.

Plantar intrinsic foot muscle activity and its relationship with postural sway during tiptoe standing in ballet dancers and non-dancers

BackgroundMinimizing postural sway during tiptoe standing is essential for ballet dancers. Investigation of the activity of the plantar intrinsic foot muscles (PIFMs) may provide insight into postural sway in dancers. Herein, we compared PIFM activity during tiptoe standing between dancers and non-dancers and examined its relationship with postural sway. MethodsWe enrolled 14 female ballet dancers and 13 female non-dancers. Electromyography (EMG) amplitudes of 64 channels of PIFMs and center of pressure (COP) data were recorded during bipedal tiptoe standing tasks performed with ankle plantarflexion angles of 20°, 40°, and 60° (dancers only). The EMG amplitudes were normalized to those during the maximum voluntary contraction, and the muscle activity level and its coefficient of variation over time (EMG-CVtime) during the task were assessed. Standard deviations in the anteroposterior and mediolateral directions, velocity, and area were calculated from the COP data. ResultsMost COP and EMG variables were significantly lower in dancers than in non-dancers in both the 20° and 40° tasks (p < 0.05). Significant correlations were found between most combinations of the COP and EMG variables in both the 20° and 40° tasks in the whole cohort (r = 0.468–0.807, p ≤ 0.014). In the 60° task in dancers, COP velocity was strongly correlated with EMG-CVtime (r = 0.700, p = 0.005). ConclusionThese results provide novel evidence that the PIFMs do not require high activity, but rather that its low, steady activity is the key, to achieve less postural sway during bipedal tiptoe standing in dancers.

A gaming app developed for vestibular rehabilitation improves the accuracy of performance and engagement with exercises

IntroductionVestibular hypofunction is associated with dizziness, imbalance, and blurred vision with head movement. Vestibular rehabilitation is the gold standard recommendation to decrease symptoms and improve postural stability. The Clinical Practice Guidelines for vestibular hypofunction suggest home exercises 3–5 times daily, but patient adherence is a problem, with compliance rates often below 50%.MethodsAn app was developed to increase engagement with home exercises by providing exercises as games. This study compared the accuracy of exercise performance in a one-time session using the app versus no-app and gathered participant feedback on using the app for vestibulo-ocular reflex (VOR) and balance exercises. The app was tested with 40 adults (20 women), mean age of 67 ± 5.7 years, with symptomatic unilateral or bilateral vestibular hypofunction. Participants completed VOR exercises in pitch and yaw planes, weight-shift, and single-leg balance exercises using an inertial motion unit to move the character on the tablet screen. Participants were randomly assigned to begin the exercises with or without the app.ResultsResults show that during VOR exercises, participants achieved the prescribed frequency of head motion for the yaw plane (p ≤ 0.001) and reduced variability of head movement frequency in both the yaw (p ≤ 0.001) and pitch plane (p ≤ 0.001) in the app compared to the no-app condition. During weight-shifting exercises, a larger range of body motion was noted in the anteroposterior and mediolateral directions in the app compared to the no-app condition (p &amp;lt; 0.05). During single-leg balance exercises, pelvic motion was lower in the app versus no-app condition (p = 0.02). Participants modified their exercise performance and corrected their mistakes to a greater extent when they used the app during the VOR exercises. Participants agreed that they felt motivated while playing the games (97%) and felt motivated by the trophies (92%). They agreed that the app would help them perform the exercises at home (95%), improve their rehab performance (95%) and that it was fun to do the exercises using the app (93%).DiscussionThe results of this study show that technology that is interactive and provides feedback can be used to increase accuracy and engagement with exercises.

Assessment of Pulmonary Ventilation Using 3D Ventilation Flow Capacity-Weighted and Ventilation-Weighted Maps From 3D Ultrashort Echo Time (UTE) MRI.

Three-dimensional (3D) ventilation flow capacity-weighted (VFCW) maps together with 3D ventilation-weighted (VW) maps may help to better assess pulmonary function. To investigate the use of 3D VFCW and VW maps for evaluating pulmonary ventilation function. Prospective. Two patients (one male, 85 years old; one female, 64 years old) with chronic obstructive pulmonary disease (COPD) and nine healthy subjects (all male; 23-27 years). 3-T, 3D radial UTE imaging. 3D VFCW and VW maps were calculated from 3D UTE MRI by voxel-wise subtraction of respiratory phase images. Their validation was tested in nine healthy volunteers using slow/deep and fast/shallow breathing conditions. Additional validation was performed by comparison with single photon emission computed tomography (SPECT) ventilation maps of one healthy participant. For comparison, gravity dependence of anterior-posterior regional ventilation was assessed by one-dimensional plot of the mean signal intensity for each coronal slice. Structural similarity index measure was also calculated. Finally, VW maps and VFCW maps of two COPD patients were evaluated for emphysema lesions with reference to CT images. Wilcoxon sign-rank tests for regional Ventilation and ventilation flow capacity, analysis of variance, post-hoc t-tests and Bonferroni correction, coefficient of variation, Kullback-Liebler divergence. A P-value <0.05 was considered statistically significant. The validation of 3D VFCW and VW maps was shown by statistically significant differences in ventilation flow capacity and ventilation between the breathing conditions. Additionally, UTE-MRI and SPECT-based ventilation maps showed gravitational dependence in the anteroposterior direction. When applied to patients with COPD, the use of 3D VFCW and VW maps was able to differentiate between two patients with different phenotypes. The use of 3D VFCW and VW maps can provide regional information on ventilation function and potentially contribute to assessment of COPD subtypes and disease progression. 2 TECHNICAL EFFICACY: Stage 1.

Race and Gender Differences in Anterior Cruciate Ligament Femoral Footprint Location and Orientation: A 3D-MRI Study.

The femoral tunnel position is crucial to anatomic single-bundle anterior cruciate ligament (ACL) reconstruction, but the ideal femoral footprint position are mostly based on small-sized cadaveric studies and elderly patients with a single ethnic background. This study aimed to identify potential race- or gender-specific differences in the ACL femoral footprint location and ACL orientation, determine the correlation between the ACL orientation and the femoral footprint location. Magnetic resonance images (MRIs) of 90 Caucasian participants and 90 matched Chinese subjects were used for reconstruction of three-dimensional (3D) femur and tibial models. ACL footprints were sketched by several experienced orthopedic surgeons on the MRI photographs. The anatomical coordinate system was applied to reflect the ACL footprint location and orientation of scanned samples. The femoral ACL footprint locations were represented by their distance from the origin in the anteroposterior (A/P) and distal-proximal (D/P) directions. The orientation of the ACL was described with the sagittal, coronal and transverse deviation angles. The ACL orientation and femoral footprint position were compared by the two-sided t-test. Multiple regression analysis was used to study the correlation between the orientation and femoral footprint position. The average femur footprint A/P position was -6.6 ± 1.6 mm in the Chinese group and -5.1 ± 2.3 mm in the Caucasian group, (p < 0.001). The average femur footprint D/P position was -2.8 ± 2.4 mm in Chinese and - 3.9 ± 2.0 mm in Caucasians, (p = 0.001). The Chinese group had a mean difference of a 1.5 mm (6.1%) more posterior and 1.1 mm (5.3%) more proximal in the position from the flexion-extension axis (FEA). And the males have a sagittal plane elevation about 4-5° higher than females in both racial groups. Furthermore, for every 1% (0.40 mm) increase in A/P and D/P values, the sagittal angle decreased by about 0.12° and 0.24°, respectively; the coronal angle decreased by about 0.10° and 0.30°, respectively. For every 1% (0.40 mm) increase in D/P value, the transverse angle increased by about 0.14°. The significant race- and gender-specific differences in the femoral footprint and orientation of the ACL should be taken in consideration during anatomic single-bundle ACL reconstruction. Furthermore, the quantitative relationship between the ACL orientation and the footprint location might provide some reference for surgeons to develop a surgical strategy in ACL single-bundle reconstruction and revision.

CineECG repolarization gradients predict acute hemodynamical response in CRT patients

Abstract Background Cardiac resynchronization therapy (CRT) is widely used for patients with conduction disorders and heart failure. The proportion of the CRT-non-responders can exceed 30%, which warrants search for new approaches to optimize the CRT device implantation and follow-up. CineECG is a novel cardiac anatomy-based ECG modality proposed for better visualization of the myocardial depolarization and repolarization processes. This method yielded promising results in patients with sinus rhythm but has not been tested in ventricular pacing. Purpose The aim of the present study was to evaluate CineECG-derived mean temporo-spatial isochrone (TSI) trajectory in different pacing protocols and test its association with acute hemodynamical responses in CRT patients. Methods CineECG uses a generic heart/torso model to construct the average electrical pathway within the cardiac anatomy from the 12 lead ECG. CineECG and invasive hemodynamical parameters were tested in 15 patients undergoing multisite CRT system implantation. ECG recording and hemodynamical measurements were performed simultaneously, while the patients were undergoing 4-6 biventricular pacing protocols with the same interventricular pacing delay (30 ms) and different left ventricular (LV) lead localizations (apical, basal, multisite). LV dP/dt max was tested for association with the parameters of standard ECG (QRS duration, QT duration, Tpeak-Tend duration) and CineECG pathway parameters. The latter pathway directions were computed for QRS and ST-T intervals for anteroposterior (X), left-to-right (Y), and apicobasal (Z) directions. Results Biventricular protocols did not differ between each other in LV dP/dt. In univariate linear regression analysis, LV dP/dt max was associated with QRS and ST-T pathway directions (Figure 1 - table). The left-to-right (Y) and apicobasal (Z) ST-T pathway directions remained independent predictors of LV dP/dt max in multivariate linear regression analysis with the adjustment for a pacing protocol [regression coefficient 571.6 (319.3 – 823.8), p&amp;lt;0.001; regression coefficient -406.9 (-636.7 – -177.2), p=0.001, respectively]. Optimal repolarization sequences associated with better acute hemodynamic responses assessed by LV dP/dt max were from right to left and from base to apex (Figure 2). Conclusion CineECG repolarization pathway gradients in the left-to-right and apicobasal directions outperform temporal ECG parameters and predict the acute hemodynamical response in biventricular pacing protocols in CRT patients.

Dynamic postural control in women athletes with and without nonspecific low back pain with high and low pain-related anxiety- A case-control study

BackgroundLow back pain is common among athletes and it has been shown that postural control is altered in the general population with nonspecific low back pain (NSLBP). Psychological factors may also predispose individuals to risk of altered postural control. Dynamic postural control is essential to the performance of athletes. This study aimed to compare the dynamic postural control between women athletes with and without NSLBP with high and low pain-related anxiety.MethodsForty-five female athletes (15 NSLBP with high pain-related anxiety, 15 NSLBP with low pain-related anxiety, and 15 healthy (control)) were included. Pain-related anxiety was assessed using the Pain Anxiety Symptom Scale-20 (PASS-20). Based on the cut-off score of 30 for the total score of PASS-20, NSLBP patients were classified into two groups of low and high pain-related anxiety. Participants performed double-leg vertical drop jump (DVJ) and single-leg vertical jump (SVJ) tests on a Kistler force plate (type 9260AA6, Kistler Instruments Inc, Switzerland). The total root mean square (RMS) of the center of pressure (COP), COP displacement in the anteroposterior (AP), and mediolateral (ML) directions, COP mean velocity, and time to stabilization (TTS) in vertical, AP, and total directions were extracted from COP and ground reaction force data using MATLAB software. One-way Analysis of variance (ANOVA) and Welch’s ANOVA were employed to compare the groups. In case of significant findings, post hoc tests were performed.ResultsThe results showed that during DJV, athletes with high pain-related anxiety had significantly greater TTS in all total, AP, and ML directions than other groups (P < 0.05). Also, the control group showed greater total RMS distance during DJV than either NSLBP group. However, no significant differences in TTS and COP parameters were found between the groups during SVJ (P > 0.05).ConclusionsThe findings suggest that pain-related anxiety may contribute to athletes’ postural control strategies. Therefore, it is important to consider the level of pain-related anxiety during planning postural control exercises for women athletes with NSLBP.

Prediction of Three-Directional Ground Reaction Forces during Walking Using a Shoe Sole Sensor System and Machine Learning.

We developed a shoe sole sensor system with four high-capacity, compact triaxial force sensors using a nitrogen added chromium strain-sensitive thin film mounted on the sole of a shoe. Walking experiments were performed, including straight walking and turning (side-step and cross-step turning), in six healthy young male participants and two healthy young female participants wearing the sole sensor system. A regression model to predict three-directional ground reaction forces (GRFs) from force sensor outputs was created using multiple linear regression and Gaussian process regression (GPR). The predicted GRF values were compared with the GRF values measured with a force plate. In the model trained on data from the straight walking and turning trials, the percent root-mean-square error (%RMSE) for predicting the GRFs in the anteroposterior and vertical directions was less than 15%, except for the GRF in the mediolateral direction. The model trained separately for straight walking, side-step turning, and cross-step turning showed a %RMSE of less than 15% in all directions in the GPR model, which is considered accurate for practical use.

A new computed tomography protocol to assess the olfactory cleft

INTRODUCTION: The olfactory cleft is a region of significant importance within the nasal cavity, given the heightened focus on olfactory disorders in recent years. It is considered a 3-dimensional space that starts at the most anterior olfactory filament and ends just anteriorly to the sphenoid sinus. This study aimed to outline the profile of the olfactory cleft as an anatomical area of extreme relevance in the diagnosis of diseases of the nose, paranasal sinuses and olfactory disorders. The aim to establish parameters of radiological normality for the olfactory cleft enables us to recognize and differentiate nasal disorders by identifying the widening or narrowing of the olfactory cleft during the preoperative assessment, thus facilitating the planning of the optimal treatment. This supports a theory about the evolution and development of the nose (Evo Devo Theory) that shows the olfactory nose (ethmoid and olfactory cleft) represents the seat of most diseases of the nose and paranasal sinuses. MATERIALS AND METHODS: 700 random CT scans of the nose and sinuses have been studied. A homogeneous group of CT scans of patients without paranasal sinus diseases were included in this study, seeking to define a reference anatomical measure as a criterion for tomographic normality. Measurements of the olfactory cleft were taken in the lateral-lateral direction between the middle concha and the septum on each side of the nose cavity at three specific anatomical points in the anterior skull base in the anteroposterior direction, corresponding to the beginning, middle and end of the olfactory cleft. For data analysis, exploratory statistical techniques have been used that allowed a better visualization of the general characteristics of the data. The appropriate statstical analysis was performed using Statistical Package for Social Sciences (SPSS). RESULTS: According to the statistical analysis performed, the reference values that were found evaluating and studying the three points were: at the first point - First Olfactory Neuron Point (FONP) – was 1.3 to 2.1 mm, at the second point - Middle Point (MP) was 1.1 to 1.6 mm, and at the third point – Sphenoethmoidal recess point (SERP) was 1.1 to 1.8 mm. The average in the first point was 1.78 mm, while in the second and third points were 1.41 and 1.48 mm, respectively. CONCLUSION: It is concluded that the tomographic olfactory cleft reference values are respectively: at the first point – First Olfactory Neuron Point- 1.3 to 2.1 mm, at the second point - Middle Point - 1.1 to 1.6 mm, and at the third point – Sphenoethmoidal recess point -1.1 to 1.8 mm.

Syndesmosis dislocation and ankle ligament stress in the posterior malleolus fracture fixated – “in vitro analysis”

PurposeThe objectives of this study were to compare syndesmosis dislocation and ankle ligament stress after the fixation of the posterior malleolus fracture (PMF) with four different techniques by Finite Element Analysis (FEM). MethodsFour internal fixation techniques used for fixation of PMF were assessed by FEM: posterior one-third tubular 3.5 mm buttress plate (PP) with one screw (PP 1 screw), PP with two screws (PP 2 screws), two cannulated 3.5 mm lag screws in the anteroposterior (AP) direction (AP lag screws), and two posteroanterior (PA) cannulated 3.5 mm lag screws (PA lag screws). PMF with 30% fragment size was simulated through computational processing reconstructed from computed tomography (CT). The simulated loads of 700 N and 1200 N were applied to the proximal tibial end. The FEM evaluated the syndesmosis dislocation (mm) and stress values of the posterior tibiofibular ligament (PTFL) (in Kpa) and deltoid ligament (in Kpa) in the four mentioned subgroups. ResultsWe found that with a load of 700 N, syndesmosis dislocation varied from 6.5 to 7.9 mm, being the lowest and greatest for PA lag screw and PP 1 screw, respectively. In all groups was observed a greater dislocation in the syndesmosis at 1200 N of load. We observed that the stress values on the PTFL were lower for AP lag screws and PP 2 screws with 700 N and 1200 N, respectively. For both loads, PP 1 screw presented the greatest stress. Regarding the stress in the deltoid ligament, the AP lag screws presented the lowest stress for 700 N and PP 1 screw for 1200 N. For all fixation techniques, the syndesmosis displacement and ligament stresses were higher when 1200 N were imposed. ConclusionThis study demonstrated that PMF fixed with lag screws presents greater stability in the distal tibiofibular syndesmosis and higher joint loadings promoted greater displacement and ligaments stress, regardless of the fixation technique. Besides, lower stress in the syndesmosis is accompanied by a greater load on the deltoid ligament.

How should the margin of stability during walking be expressed to account for body size?

When expressing the margin of stability as a distance, it does not directly estimate the perturbation magnitude needed to change stability states. Additionally, it is unknown how body size may influence this measure. Therefore, we propose other expressions of stability margins, including that of an impulse, a change in center of mass velocity, and a scaled, unitless impulse. The purpose of this study was to determine the influence of body size on these margin expressions using walking data from children and adults. We anticipated that margins expressed as an impulse would have strong correlations with body mass and height, as well as large between-group differences. We predicted that scaling this impulse value would result in small correlations and between-group effect sizes. We calculated each stability margin at minimum lateral values and in the anteroposterior directions at mid-swing and foot strike. In the lateral direction, margins expressed as an impulse had strong correlations with body size (r≥0.58, p<0.01) and large between-group differences (|d|≥1.07, p<0.01). The other expressions did not have strong positive correlations (|r|≤0.20) or large between-group effects (|d|≤0.44). In the anteroposterior directions, impulse margins had strong correlations with body size (|r|≥0.83, p<0.01) and large between-group differences (|d|≥1.74, p<0.01). The scaled, unitless impulse margin was the only variable that resulted in small, non-significant differences (|r|≤0.22, p≥0.24) as well as small between-group effect sizes (|d|≤0.46, p≥0.22). We propose expressing stability margins as an impulse. If scaling is needed, we encourage using the scaled, unitless impulse.