Non-dominant Arm Research Articles

Safety and immunogenicity of a ChAdOx1 vaccine against Rift Valley fever in UK adults: an open-label, non-randomised, first-in-human phase 1 clinical trial

Rift Valley fever is a viral epidemic illness prevalent in Africa that can be fatal or result in debilitating sequelae in humans. No vaccines are available for human use. We aimed to evaluate the safety and immunogenicity of a non-replicating simian adenovirus-vectored Rift Valley fever (ChAdOx1 RVF) vaccine in humans. We conducted a phase 1, first-in-human, open-label, dose-escalation trial in healthy adults aged 18-50 years at the Centre for Clinical Vaccinology and Tropical Medicine, Oxford, UK. Participants were required to have no serious comorbidities or previous history of receiving an adenovirus-based vaccine before enrolment. Participants were non-randomly allocated to receive a single ChAdOx1 RVF dose of either 5 × 109 virus particles (vp), 2·5 × 1010 vp, or 5 × 1010 vp administered intramuscularly into the deltoid of their non-dominant arm; enrolment was sequential and administration was staggered to allow for safety to be assessed before progression to the next dose. Primary outcome measures were assessment of adverse events and secondary outcome measures were Rift Valley fever neutralising antibody titres, Rift Valley fever GnGc-binding antibody titres (ELISA), and cellular response (ELISpot), analysed in all participants who received a vaccine. This trial is registered with ClinicalTrials.gov (NCT04754776). Between June 11, 2021, and Jan 13, 2022, 15 volunteers received a single dose of either 5 × 109 vp (n=3), 2·5 × 1010 vp (n=6), or 5 × 1010 vp (n=6) ChAdOx1 RVF. Nine participants were female and six were male. 14 (93%) of 15 participants reported solicited local adverse reactions; injection-site pain was the most frequent (13 [87%] of 15). Ten (67%) of 15 participants (from the 2·5 × 1010 vp and 5 × 1010 vp groups only) reported systemic symptoms, which were mostly mild in intensity, the most common being headache (nine [60%] of 15) and fatigue (seven [47%]). All unsolicited adverse events reported within 28 days were either mild or moderate in severity; gastrointestinal symptoms were the most common reaction (at least possibly related to vaccination), occurring in four (27%) of 15 participants. Transient decreases in total white cell, lymphocyte, or neutrophil counts occurred at day 2 in some participants in the intermediate-dose and high-dose groups. Lymphopenia graded as severe occurred in two participants in the 5 × 1010 vp group at a single timepoint, but resolved at the subsequent follow-up visit. No serious adverse events occurred. Rift Valley fever neutralising antibodies were detectable across all dose groups, with all participants in the 5 × 1010 vp dose group having high neutralising antibody titres that peaked at day 28 after vaccination and persisted through the 3-month follow-up. High titres of binding IgG targeting Gc glycoprotein were detected whereas those targeting Gn were comparatively low. IFNγ cellular responses against Rift Valley fever Gn and Gc glycoproteins were observed in all participants except one in the 5 × 1010 vp dose group. These IFNγ responses peaked at 2 weeks after vaccination, were highest in the 5 × 1010 vp dose group, and tended to be more frequent against the Gn glycoprotein. ChAdOx1 RVF was safe, well tolerated, and immunogenic when administered as a single dose in this study population. The data support further clinical development of ChAdOx1 RVF for human use. UK Department of Health and Social Care through the UK Vaccines Network, Oak Foundation, and the Wellcome Trust. For the Swahili translation of the abstract see Supplementary Materials section.

Ventilatory response to peripheral chemoreflex and muscle metaboreflex during static handgrip in healthy humans: evidence of hyperadditive integration.

What is the central question of this study? What is the effect of peripheral chemoreflex and muscle metaboreflex integration on ventilation regulation, and what is the effect of integration on breathing-related sensations and emotions? What is the main finding and its importance? Peripheral chemoreflex and muscle metaboreflex coactivation during isocapnic static handgrip exercise appeared to elicit a hyperadditive effect with regard to ventilation and an additive effect with regard to breathing-related sensations and emotions. These findings reveal the nature of the integration between two neural mechanisms that operate during small-muscle static exercise performed under hypoxia. Exercise augments the hypoxia-induced ventilatory response in an exercise intensity-dependent manner. A mutual influence of hypoxia-induced peripheral chemoreflex activation and exercise-induced muscle metaboreflex activation might mediate the augmentation phenomenon. However, the nature of these reflexes' integration (i.e., hyperadditive, additive or hypoadditive) remains unclear, and the coactivation effect on breathing-related sensations and emotions has not been explored. Accordingly, we investigated the effect of peripheral chemoreflex and muscle metaboreflex coactivation on ventilatory variables and breathing-related sensations and emotions during exercise. Fourteen healthy adults performed 2-min isocapnic static handgrip, first with the non-dominant hand and immediately after with the dominant hand. During the dominant hand exercise, we (a) did not manipulate either reflex (control); (b) activated the peripheral chemoreflex by hypoxia; (c) activated the muscle metaboreflex in the non-dominant arm by post-exercise circulatory occlusion (PECO); or (d) coactivated both reflexes by simultaneous hypoxia and PECO use. Ventilation response to coactivation of reflexes (mean±SD, 13±6l/min) was greater than the sum of responses to separated activations of reflexes (mean±SD, 8±8l/min, P=0.005). Breathing-related sensory and emotional responses were similar between coactivation of reflexes and the sum of separate activations of reflexes. Thus, the peripheral chemoreflex and muscle metaboreflex integration during exercise appeared to be hyperadditive with regard to ventilation and additive with regard to breathing-related sensations and emotions in healthy adults.

Comparison of visual and electromyographic assessments with train-of-four stimulation of the ulnar nerve: a prospective cohort study.

The use of a peripheral nerve stimulator to assess the level of neuromuscular blockade tasks the anesthesia clinician with subjectively assessing the response to neurostimulation. In contrast, objective neuromuscular monitors provide quantitative information. The purpose of this study was to compare subjective evaluations from a peripheral nerve stimulator with objective measurements of neurostimulation responses from a quantitative monitor. Patients were enrolled preoperatively, and intraoperative neuromuscular blockade management was at the discretion of the anesthesiologist. Electromyography electrodes were placed over the dominant or nondominant arm in a randomized fashion. Following onset of nondepolarizing neuromuscular blockade, the ulnar nerve was stimulated, the response was measured with electromyography, and anesthesia clinicians, who were blinded to the objective measurements, subjectively (visually) evaluated the response to neurostimulation. Fifty patients were enrolled and 666 neurostimulations were performed at 333 different time points. Anesthesia clinicians subjectively overestimated the response of the adductor pollicis muscle following neurostimulation of the ulnar nerve 155/333 (47%) of the time when compared with objective electromyographic measurements. When subjective evaluations and objective measurements differed to any degree, subjective evaluations were higher than objective measurements 155/166 (92%) of the time (95% CI, 87 to 95; P < 0.001), representing significant evidence that subjective evaluation overestimates the response to train-of-four stimulation. Subjective observations of a "twitch" do not consistently correspond to objective measurements of neuromuscular blockade with electromyography. Subjective evaluation overestimates the response to neurostimulation and may be unreliable for determining the depth of block or confirming adequate recovery.

Local heating and cooling with isometric exercise training as a strategy to improve size and performance

The purpose of this study was to explore the effects of local heating and cooling with isometric exercise training of upper arm and forearm. College-aged (n=12; 21±1 y) volunteers performed 4-wk isometric exercise training of the non-dominant arm (upper arm, isometric bicep curl; forearm, handgrip), while the dominant arm served as the control. Training was performed 3x/wk and consisted of 1 set of isometric handgrip and bicep curl until volitional exhaustion at 60% pre-training MVC for the forearm (handgrip) and 1RM for the upper arm (bicep curl). Randomized ordering of heating (40°C; 15 min) and cooling (12°C; 15 min) preceded each training session. Indirect assessment of muscle size (fat-free cross-sectional area [FFCSA]) was made before and after the training period via skin fold and limb circumference measures. Biceps 1RM increased significantly (p &lt; 0.05) after the intervention in both conditions (trained: +6%; control: +7%), whereas only the control arm increased time to fatigue (+40%; p &lt; 0.05). FFSCA of the upper arm remained unchanged (p&gt;0.05) in both conditions. An effect of time was noted for forearm MVC (+8%; p &lt; 0.05), while both groups increased (p &lt; 0.05) time to fatigue (trained: +82%; control: +64%). A trend toward an effect of time was also noted for FFCSA of the forearm (+3%; p &lt;.10). While the intervention employed here led to many notable adaptations, the thermal stress did not appear to exert a clear benefit. Coupled with the practicality and feasibility, improving size and performance in such a short time frame has therapeutic and ergogenic aid implications.

Different Control Strategies Drive Interlimb Differences in Performance and Adaptation during Reaching Movements in Novel Dynamics.

Humans exhibit lateralization such that most individuals typically show a preference for using one arm over the other for a range of movement tasks. The computational aspects of movement control leading to these differences in skill are not yet understood. It has been hypothesized that the dominant and nondominant arms differ in terms of the use of predictive or impedance control mechanisms. However, previous studies present confounding factors that prevented clear conclusions: either the performances were compared across two different groups, or in a design in which asymmetrical transfer between limbs could take place. To address these concerns, we studied a reach adaptation task during which healthy volunteers performed movements with their right and left arms in random order. We performed two experiments. Experiment 1 (18 participants) focused on adaptation to the presence of a perturbing force field (FF) and experiment 2 (12 participants) focused on rapid adaptations in feedback responses. The randomization of the left and right arm led to simultaneous adaptation, allowing us to study lateralization in single individuals with symmetrical and minimal transfer between limbs. This design revealed that participants could adapt control of both arms, with both arms showing similar performance levels. The nondominant arm initially presented a slightly worst performance but reached similar levels of performance in late trials. We also observed that the nondominant arm showed a different control strategy compatible with robust control when adapting to the force field perturbation. EMG data showed that these differences in control were not caused by differences in co-contraction across the arms. Thus, instead of assuming differences in predictive or reactive control schemes, our data show that in the context of optimal control, both arms can adapt, and that the nondominant arm uses a more robust, model-free strategy likely to compensate for less accurate internal representations of movement dynamics.

야구선수 포지션별 투수와 야수의 Functional Movement Screen(FMS) 및 Upper Quarter Y-Balance Test(UQ-YBT) 비교 분석

The purpose of this study is to compare the differences in FMS and Y-balance between pitchers and fielders in baseball. A total of 20 baseball players (pitchers: 10, fielders: 10) who are active status as collegiate athletes were recruited from Busan, Ulsan, and Gyeongnam. Independent t-tests were used to verify the statistical differences between pitchers and fielders. The significance level was set at α＜.05. As a result of this study, there was a significant difference in in-line lunge and shoulder mobility (p＜.05). Although there was no significant difference in UQ-YBT, pitchers showed 2~4% higher score for the non-dominant arm compared to the dominant arm in three directions. In other words, the overall score of the pitchers showed an imbalance between the dominant arm and the non-dominant arm. The difference in the scores of the FMS was not large, but the average of the total scores was 15 to 16 points. Since a score of 14 or less increases the incidence of injury, functional movement seems to need improvement. It seems that FMS training is needed to improve functional movement. In particular, baseball players with high upper extremity injuries can manage left-right imbalance through UQ-YBT, so systematic management for each individual player will be possible.

Seasonal Variation in Upper Limb Size, Volume, Fluid Distribution, and Lymphedema Diagnosis, Following Breast Cancer Treatment.

Background: Breast cancer-related lymphedema (BCRL) is a common complication of breast cancer treatment. Anecdotal and qualitative research suggests that heat and hot weather cause an exacerbation of BCRL; however, there is little quantitative evidence to support this. The aim of this article is to investigate the relationship between seasonal climate variation and limb size, volume, fluid distribution, and diagnosis in women following breast cancer treatment. Methods and Results: Women older than the age of 35 years who had undergone treatment for breast cancer were invited to participate. Twenty-five women aged between 38 and 82 years were recruited. Seventy-two percent received surgery, radiation therapy, and chemotherapy as part of their breast cancer treatment. Participants completed anthropometric, circumferential, and bioimpedance measures and a survey on three occasions: November (spring), February (summer), and June (winter). Diagnostic criteria of >2 cm and >200 mL difference between the affected and unaffected arm, and a positive bioimpedance ratio of >1.139 for a dominant arm and >1.066 for nondominant arm was applied across the three measurement occasions. No significant correlation between seasonal variation in climate and upper limb size, volume, or fluid distribution were found in women diagnosed with or at risk of developing BCRL. Lymphedema diagnosis depends on the season and diagnostic measurement tool utilized. Conclusion: There was no statistically significant variation in limb size, volume, or fluid distribution in this population across spring, summer, and winter, although there were linked trends in these values. The diagnosis of lymphedema, however, varied between individual participants throughout the year. This has important implications for the implementation/commencement of treatment and management. Further research with a larger population in different climates is required to explore the status of women with respect to BCRL. The use of common clinical diagnostic criteria did not result in consistent diagnostic classification of BCRL for the women involved in this study.

Effects of Unilateral Neuromuscular Electrical Stimulation with Illusionary Mirror Visual Feedback on the Contralateral Muscle: A Pilot Study.

We aim to examine the cross-education effects of unilateral muscle neuromuscular electrical stimulation (NMES) training combined with illusionary mirror visual feedback (MVF). Fifteen adults (NMES + MVF: 5; NMES: 5, Control: 5) completed this study. The experimental groups completed a 3-week NMES training on their dominant elbow flexor muscle. The NMES + MVF group had a mirror placed in the midsagittal plane between their upper arms, so a visual illusion was created in which their non-dominant arms appeared to be stimulated. Baseline and post-training measurements included both arms' isometric strength, voluntary activation level, and resting twitch. Cross-education effects were not observed from all dependent variables. For the unilateral muscle, both experimental groups showed greater strength increases when compared to the control (isometric strength % changes: NMES + MVF vs. NMES vs. Control = 6.31 ± 4.56% vs. 4.72 ± 8.97% vs. -4.04 ± 3.85%, p < 0.05). Throughout the training, even with the maximally tolerated NMES, the NMES + MVF group had greater perceived exertion and discomfort than the NMES. Additionally, the NMES-evoked force increased throughout the training for both groups. Our data does not support that NMES combined with or without MVF induces cross-education. However, the stimulated muscle becomes more responsive to the NMES and can become stronger following the training.

Effects of Unilateral Eccentric versus Concentric Training of Non-Immobilized Arm During Immobilization.

The present study tested the hypothesis that eccentric training (ET) of non-immobilized arm would attenuate negative effects of immobilization and provide greater protective effects against muscle damage induced by eccentric exercise after immobilization, when compared with concentric training (CT). Sedentary young men were placed to ET, CT or control group (n = 12/group), and their non-dominant arms were immobilized for 3 weeks. During the immobilization period, ET and CT groups performed 5 sets of 6 dumbbell curl eccentric-only and concentric-only contractions, respectively at 20-80% of maximal voluntary isometric contraction (MVCiso) strength over six sessions. MVCiso torque, root-mean square (RMS) of electromyographic activity during MVCiso, and bicep brachii muscle cross-sectional area (CSA) were measured before and after immobilization for both arms. All participants performed 30 eccentric contractions of the elbow flexors (30EC) by the immobilized arm after the cast was removed. Several indirect muscle damage markers were measured before, immediately after, and for 5 days following 30EC. ET increased MVCiso (17 ± 7%), RMS (24 ± 8%), and CSA (9 ± 2%) greater (P < 0.05) than CT (6 ± 4%, 9 ± 4%, 3 ± 2%) for the trained arm. The control group showed decreases in MVCiso (-17 ± 2%), RMS (-26 ± 6%), and CSA (-12 ± 3%) for the immobilized arm, but these changes were attenuated greater (P < 0.05) by ET (3 ± 3%, -0.1 ± 2%, 0.1 ± 0.3%) than CT (-4 ± 2%, -4 ± 2%, -1.3 ± 0.4%). Changes in all muscle damage markers after 30EC were smaller (P < 0.05) for the ET and CT than control, and ET than CT group (e.g., peak plasma creatine kinase activity, ET: 860 ± 688, CT: 2,390 ± 1104, control: 7,819 ± 4,011 IU/L). These results showed that ET of the non-immobilized arm was effective for eliminating the negative effects of immobilization and attenuating eccentric exercise-induced muscle damage after immobilization.

Coronary Artery Disease and Inflammatory Activation Interfere with Peripheral Tissue Electrical Impedance Spectroscopy Characteristics-Initial Report.

The electrical properties of cells and tissues in relation to energy exposure have been investigated, presenting their resistance and capacitance characteristics. The dielectric response to radiofrequency fields exhibits polarization heterogeneity under pathological conditions. The aim of the study was to analyze the differences in changes in resistance and capacitance measurements in the range from 1 kHz to 1 MHz, combined with an assessment of the correlation between the results of electrical impedance spectroscopy (EIS) and inflammatory activation. In the prospective study, EIS was performed on the non-dominant arm in 29 male patients (median (Q1-Q3) age of 69 (65-72)) with complex coronary artery disease and 10 male patients (median (Q1-Q3) age of 66 (62-69)) of the control group. Blood samples were collected for inflammatory index analysis. The logistic regression analysis revealed a negative correlation with inflammatory indexes, including neutrophil to lymphocyte ratio (NLR) in the CAD group in the frequency of 30 kHz (p = 0.038, r = -0.317) regarding EIS resistance measurements and a positive correlation in CAD group in the frequency of 10 kHz (p = 0.029, r = -0.354) regarding EIS capacitance. The bioelectric characteristics of peripheral tissues measured by resistance and capacitance in EIS differ in patients with coronary artery disease and in the control group. Electrical impedance spectroscopy reveals a statistically significant correlation with inflammatory markers in patients with CAD.

Bone mineral density of the ultra-distal radius: are we ignoring valuable information?

Bone mineral density (BMD) measurement of a non-dominant arm is not routinely performed during dual-X-ray-absorptiometry (DXA) test, and the possible utility of ultra-distal (UDR) radius BMD is not well-studied. We evaluated in women, correlations of UDR BMD with fracture prevalence, fracture risk prediction by the fracture risk assessment tool (FRAX), and osteoporosis diagnosed by traditional sites. Women who underwent a routine DXA (including their non-dominant forearm and including UDR BMD) in a tertiary medical center were included. Risk factors relevant to FRAX calculation were assessed via a self-administered questionnaire. Spearman correlations of UDR BMD to 10-year risks of major osteoporotic and hip fractures (assessed by FRAX) were explored. The possible added value of UDR BMD in explaining prevalent osteoporotic fractures was assessed using a multivariable regression model incorporating age and traditional osteoporosis diagnosis. The study included 1245 women with a median age of 66years (interquartile range: 59-73), of whom 298 (24%) had UDR T-score ≤ - 2.5 and 154 (12%) reported prior fractures. UDR BMD was significantly negatively correlated with FRAX risk score for hip and major osteoporotic fractures (R = - 0.5 and R = - 0.41, respectively; P < 0.001). UDR T-score ≤ - 2.5 was associated with higher fracture prevalence (19% vs 10%; P < 0.001) and remained significant after adjusting for traditional BMD and age (OR 1.49, 1.01-2.19; P = 0.043). UDR BMD correlates both with prior fractures and with predicted fracture risks and might pose added value over traditional DXA sites.

Tefillin use induces preconditioning associated changes in heart rate variability.

Short bouts of occlusion of blood flow can induce a preconditioning response that reduces subsequent damage from longer periods of ischemia. It has been shown that ischemic preconditioning (IPC) can be elicited remotely (RIPC) through limitation of blood flow and as recently described via only pain sensation. Non-obstructive banding (NOB) through the donning of tefillin (a box with sacred texts attached to a leather strap that is traditionally bound to the non-dominant arm of Jewish adults during morning prayers) has been shown to elicit an RIPC response at least partially through pain sensation. This study evaluated the effects of NOB on heart rate variability (HRV) dependent factors that are known to be affected by various RIPC stimuli. We recruited 30 healthy subjects and subjected them to NOB versus control and found various HRV markers associated with RIPC to be changed in the NOB group. This finding provides further evidence that tefillin, likely through NOB induced RIPC changes, may still be a viable clinical pathway to prevent and decrease the morbidity associated with ischemic events.

ESTABLISHING PHYSICAL ACTIVITY OF 3RD – 4TH – GRADERS WITH ACCELEROMETERS

Adolescents’ physical activity is and must be an essential part of their daily routine for proper and balanced growth and development. The use of accelerometry, a method that records the motor activity time spent in a lying or sitting position over twenty-four hours, is well-known. The actual data about a person’s movements enables us to be accurate and even to analyze the quantity and quality of those movements. We examined 135 children (mean age 129 months) with accelerometers Axivity model AX3, positioned around the wrist around the non-dominant arm. Based on consults, we established average values per twenty-four hours, namely – an average of 38.32% of the time children spent in a sitting position, 6.41% (92 min) they were engaged in a low activity, 15.42% (222 min - in a moderate activity, 1.79% (26 min) – in a high activity; and 38.06% of the time they spent sleeping. We found a weak correlation dependence r = -.263 (95%) between the body fat and the duration of the time spent in high activity.

Reliability of two devices for shoulder strength assessment: Wii Fit Balance Board and hand-held dynamometer.

The aim of this study was to compare the reliability and agreement between two devices - Wii Fit Balance Board (WBB) versus Hand-Held Dynamometer (HHD) to measure isometric strength during the athletic shoulder (ASH) test in healthy amateur rugby players. Fifteen males (23.73 ± 2.8 years) completed two testing sessions. Maximal isometric contractions using the dominant arm (D) and non-dominant arm (ND) against a WBB and HHD were assessed at three angles of abduction (180°, 'I'; 135°, 'Y' and 90°, 'T'), in a prone lying position. The results indicate a very large correlation between the HHD and the WBB. WBB provides acceptable reliability at I-Test D (CV = 9.97%, ICC = 0.88) and HHD in the I-Test D (CV = 8.90%, ICC = 0.94), I-Test ND (CV = 8.60%, ICC = 0.95) in peak strength values. The HHD is most reliable in D ASH I-Y-T (CV = 10.94%) and WBB (CV = 11.05%). In the ND ASH I-Y-T test, the HHD is the most reliable (CV = 12.5%) compared to the WBB (CV = 14.43%). These results suggest that WBB is a reliable device to assess strength in the ASH test with a very large correlation with the HHD. WBB and HHD are two affordable devices to assess isometric shoulder strength.

Muscle damage induced by maximal eccentric exercise of the elbow flexors after 3-week immobilization.

The present study investigated the effects of a 3-week immobilization (IM) on muscle damage induced by maximal eccentric exercise (MaxEC) to test the hypothesis that the IM would make muscles prone to muscle damage. Young healthy sedentary men were pseudo-randomly assigned to IM or control group (n=12/group). Non-dominant arms of the IM group participants were immobilized at 90° elbow flexion by a cast for 21 days. All participants performed MaxEC consisting of five sets of six elbow flexor contractions by lowering a dumbbell set at 100% of pre-exercise maximal voluntary isometric contraction (MVC) strength of the non-dominant arm. This was performed at 2 days after the cast removal for the IM group. MVC torque, range of motion (ROM), muscle thickness (MT), muscle hardness, position sense (PS), and joint reaction angle (JRA) of the elbow flexors were measured at baseline, post-immobilization, and before, immediately after, and one to 5 days after MaxEC. The IM decreased MVC torque (-17 ± 2%), ROM (-2 ± 1%), MT (-7 ± 3%), and JRA (-12 ± 6%), and increased in muscle hardness (20 ± 6%) and PS (11 ± 2%) (p < 0.05). Changes in MVC (e.g., 2 days: -40± 5 vs. -30 ± 9%), ROM (2 days: -11 ± 2 vs. -9 ± 3%), muscle soreness (peak: 63 ± 22 vs. 48 ± 14 mm), plasma CK activity (peak: 7820 ± 4011 vs. 4980 ± 1363 IU/L), PS (maximal change: -23 ± 2 vs. -18 ± 3%), and JRA (maximal change: -37 ± 4 vs. -26 ± 3%) after MaxEC were greater (p < 0.05) for the IM than control group. These results supported the hypothesis and showed that the IM made the muscles more vulnerable to muscle damage induced by eccentric exercise.

Assessment of the Ulnar Collateral Ligament of the Elbow Using Ultrasonic Shear Wave Elastography in Professional Baseball Players.

Injury to the ulnar collateral ligament (UCL) of the elbow can cause chronic pain and loss of throwing ability. Ultrasonic shear wave elastography (SWE) is a new imaging method that can be used for quantitative assessment of tissue elasticity. To evaluate the properties of the UCL in professional baseball players using SWE. Cross-sectional study; Level of evidence, 3. This study included 35 professional baseball players (mean age, 23.0 years) without elbow injuries. Both elbows of each player were examined using ultrasound, and comparisons between the dominant and nondominant arms were conducted. The thickness of the anterior bundle of the UCL at its midportion was measured in the resting position on ultrasound. We also measured the difference in the ulnohumeral joint space with and without gravity stress on the forearm. Tissue elasticity was evaluated using a built-in software program. The relationship between UCL elasticity and ultrasound findings was analyzed using the Pearson correlation coefficient. The mean ± SD thickness of the UCL was significantly greater in the dominant arm versus the nondominant arm (6.0 ± 1.4 vs 5.3 ± 1.3 mm; P = .004). The mean joint space difference was significantly wider in the dominant arm as compared with the nondominant arm (0.81 ± 0.42 vs 0.52 ± 0.31 mm; P = .002), and the mean UCL elasticity was lower in the dominant arm than in the nondominant arm (34.9 ± 11.6 vs 43.3 ± 10.6 kPa; P = .002). UCL elasticity was negatively correlated with UCL thickness (r = -0.27; P = .02) and joint space difference (r = -0.34; P = .003). In professional baseball players, the elbow UCL of the dominant arm demonstrated increased thickness, with a larger joint space gap on gravity stress and lower elasticity in SWE as compared with the nondominant arm. Greater medial joint laxity can be predicted by assessing the elasticity of the UCL using SWE.

Acute influences of tennis services on cardiac output and brachial hemodynamics in young male tennis players.

This study aimed to examine the influences of tennis service exercise on cardiac output (CO) and bilateral brachial hemodynamics in young tennis players. Experimental study. Ten young male tennis players (21 ± 2 years of age) participated. Each performed 100 tennis services without a return shot for experimental tennis exercise. Cardiovascular hemodynamic variables, including bilateral brachial blood flow (BF), shear rate (SR), blood pressure, and CO, were collected under three conditions: 1) baseline, 2) immediately after the tennis services (post), and 3) 1 h after the tennis services (1-hour). The positive incremental area under the curve (iAUC) for brachial hemodynamic variables was calculated. Immediately after the 100 tennis services, CO, brachial BF, SR, and brachial vascular conductance (VC) in the dominant and non-dominant arms increased (p < 0.05). At the 1-hour condition, CO returned to baseline; the brachial BF, SR, and VC in the non-dominant arm returned to baseline levels, whereas the same variables in the dominant arm remained increased. The iAUC for brachial BF and VC in the dominant arm was higher than that in the non-dominant arm. Furthermore, the brachial BF/CO ratio index in the dominant arm increased at the post and 1-hour conditions, whereas that in the non-dominant arm was unchanged. Tennis service exercise specifically increases brachial BF, SR, and VC in the dominant arm, independent of increased CO. Our findings contribute to unveiling the underlying mechanisms of brachial artery adaptations in tennis players.

Longitudinal Median Nerve Ultrasound Changes in Individuals With Spinal Cord Injury and an Age- and Sex-Matched Nondisabled Cohort.

To assess the natural history for development of carpal tunnel syndrome (CTS) in persons with acute spinal cord injury (SCI) at 1 year postdischarge from initial rehabilitation and to assess baseline median nerve (MN) cross-sectional area (CSA) above/below 10 mm2 correlates with any longitudinal changes in quantitative ultrasound (US) of the MN. A prospective cohort study of persons with acute SCI evaluated for CTS using quantitative US and compared to a group without SCI (non-SCI). Academic medical center. N=69 total (N=34 SCI, N=35 non-SCI). The average age in both groups was 28 and the SCI group included 30 males and 2 females and the non-SCI group included 30 males and 3 females. Not applicable. The primary outcome was the change in quantitative US parameters of the MN, including CSA and grayscale, from baseline to 1-year follow-up in those with SCI and those without SCI. CTS symptomatology and physical exam sum score and US measures for dominant and nondominant arms were considered secondary outcomes. The SCI had darker nerves at baseline (P=.036, nondominant), greater CTS symptoms at follow-up (P≤.036, bilateral), and no differences in all change scores (all P≥.056). Individuals with smaller nerves at baseline had larger increases in nerve size (P=.029, nondominant) vs those with larger nerves. Change in CTS symptoms CSA (nondominant) and nerve echogenicity (dominant) were inversely associated with their respective baseline values (all P≤.045). We observed few differences between the SCI group and the non-SCI control group and between those with smaller vs larger MN. In general, MN pathology changes (CTS symptoms and US variables) over 1 year were more common in the nondominant arm and appear to be a function of MN pathology at enrollment. Individuals with SCI may experience increased CTS symptoms as soon as 1 year after injury.

Injury-mechanism directness as a key factor for fracture laterality in pediatric extremity fractures

BackgroundAssociations between certain extremity fracture sites and laterality in pediatric trauma are well known, whereas the rationale for such laterality tendencies are unclear. We hypothesized that the laterality tendency of a specific fracture would be affected by directness of injury mechanism and not by the fracture site itself. MethodsWe retrospectively enrolled 1382 children (aged 2–16 years) who were diagnosed with extremity fractures sustained during loss-of-balance situations and investigated the laterality tendencies (dominant vs. non-dominant extremity) of specific fracture sites. Multivariate analyses were sequentially performed to adjust for potential confounding variables-with and without injury-mechanism directness as a covariate. ResultsIn the upper extremities, the non-dominant side was more prone to fractures (p < 0.001), especially of the distal supracondylar humerus, radial and/or ulnar shaft, and distal radius. In the lower extremities, the dominant side was more frequently fractured (p < 0.001), especially at the tibial shaft and distal tibia. However, the predisposing effects of specific fracture sites on fracture laterality were not statistically significant when in analysis adjusted for injury-mechanism directness as a covariate. Fracture laterality was affected by whether the injury mechanism was direct or indirect. Indirect injury to the upper extremity was strongly associated with non-dominant arm injury (odds ratio 0.686 [95% CI 0.517–0.991]; p = 0.009), whereas indirect injury to the lower extremity was strongly associated with dominant leg injury (odds ratio 2.138 [95% CI 1.444–3.165]; p < 0.001). ConclusionsInjury-mechanism directness, rather than fracture site itself, is a key factor that affects fracture laterality in pediatric extremity fractures. These findings are helpful for improving our understanding of which factors may affect fracture laterality among children.

PMON265 First Ever Placebo-Controlled Randomised Study of Testosterone on Ambulatory Blood Pressure and Heart Rate in Hypogonadal Men With Uncontrolled Type 2 Diabetes – STRIDE Study

Abstract Background Testosterone has been historically believed to increase blood pressure(BP) and hence bad for heart despite no convincing evidence to prove this. Self-administered use of anabolic steroids has adverse cardiac effects including hypertension. Many RCTs that have looked at the effect of TRT have been BP measurements using mercury sphygmomanometer. Our study is the first RCT looking at the effect of testosterone on ambulatory BP in patients with type 2 diabetes and hypogonadism. Research design and methods: This is a randomised double blinded placebo-controlled add-on trial of intramuscular testosterone undecanoate (Nebido®) administered every 12 weeks in 65 hypogonadal men with poorly-controlled diabetes. Phase 1 patients were randomly assigned to either treatment or placebo arm for 6 months of TRT. Phase 2 was an open-labelled phase for 6 months and patients on placebo moved on to the treatment group wherein patients in the treatment group continued. Diurnal Ambulatory-BP measurements were performed with Spacelabs 90217 mounted on the non-dominant upper arm over 24-hours. Results Mean age of the cohort was 59(42-77)years. 55.4% of the patients had hypertension at baseline. Baseline characteristics were comparable between active/placebo groups apart from cardiovascular disease and hypertension which were significantly higher in the active group compared to placebo group (n=28 vs n=18, p=0.05), (n=23 vs n=13, p=0.008) respectively. There was no significant difference in 24-hours ambulatory average SBP or DBP before and after TRT for 6 months (SBP p=0.407, DBP p=0.649). There were no significant changes in average daytime or night-time SBP (p=0.291), (p=0.295) respectively or average daytime DBP (p=0.566) or night-time DBP (p=0.879) either. There was no significant difference in the total average heart rate and day time average heart rate however night time average heart rate showed a significant reduction of around 4 beats/minute (p=0.046) between the two groups at 6 months. There was no significant difference in the values for the above parameters in the normotensive group (average baseline ambulatory BP≤ 140/90 mm of Hg) and hypertensive group (≥ to 140/90 mm of Hg) either. There was no change in antihypertensive medications in the first 6 months. Mean 24-hour ambulatory BP components were compared at 0, 3, 6, 9 and 12 months for participants in the active group before and after treatment with testosterone undecanoate. There was no significant change in the total, day or night-time systolic or diastolic BP levels before and after the treatment. Conclusions Our study concludes that testosterone given as a replacement hormone in hypogonadal patients with type 2 diabetes does not increase 24-hour ambulatory systolic or diastolic BP. Our study also shows that testosterone causes a decrease in average night-time heart rate of 4 to 5 beats/minute and the cause and significance of such a decrease needs further detailed evaluation. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.