Regional variation in bone mineral density of the distal radius.

Objectives: This study investigates the regional variation in areal bone mineral density (aBMD) at the distal radius, a critical site for osteoporosis-related fractures. Understanding aBMD distribution is essential for accurate diagnosis and management of osteoporosis. Methods: The study involved 261 participants aged over 50. Using dual-energy X-ray absorptiometry (DXA) scans, aBMD was recorded across contiguous regions of the distal radius. Factors considered include age, sex, and hand dominance, providing a comprehensive view of aBMD distribution. Results: The findings indicated a consistent pattern in aBMD distribution along the radius, with a plateau around the one-third distance from the wrist. Notably, significant differences in aBMD were observed between age groups, especially among post-menopausal women. The study also recorded minor variations in aBMD between dominant and non-dominant forearms. Conclusions: The study's insights into aBMD variation at the distal radius have implications for osteoporosis research and clinical diagnosis. It highlights the importance of standardized region of interest placement in DXA scans for accurate assessment.

Sensorimotor faculties bias perceptual decision-making.

Decision-making is a deliberate process that seemingly evolves under our own volition. Yet, research on embodied cognition has demonstrated that higher-order cognitive processes may be influenced, in unexpected ways, by properties of motor and sensory systems. Here we tested whether and how simple decisions are influenced by handedness and by asymmetries in the auditory system. Right- and left-handed participants performed an auditory decision task. In the task, subjects decided whether they heard more click sounds in the right ear or in the left ear, and pressed a key with either their right or left index finger, according to an instructed stimulus-key assignment (congruent or reversed). On some trials, there was no stimulus and subjects could choose either of the responses freely. When subjects chose freely, their choices were substantially governed by their handedness: Left-handed subjects were significantly biased to make the leftward choice, whereas right-handed subjects showed a substantial rightward bias. When the choice was governed by the sensory stimulus, subjects showed a rightward choice bias under the congruent key assignment, but this effect reversed to a leftward choice bias under the reversed key assignment. This result indicates a bias towards deciding that there were more clicks presented to the right ear. Together, our findings demonstrate that human choices can be considerably influenced by properties of motor and sensory systems.

Differential Impact of Biomechanical Constraints on Control Signal Dimensionality for Gravity Support Versus Propulsion.

Neural control of movement has to overcome the problem of redundancy in the multidimensional musculoskeletal system. The problem can be solved by reducing the dimensionality of the control space of motor commands, i.e., through muscle synergies or motor primitives. Evidence for this solution exists, multiple studies have obtained muscle synergies using decomposition methods. These synergies vary across different workspaces and are present in both dominant and non-dominant limbs. Here we explore the dimensionality of control space by examining muscle activity patterns across reaching movements in different directions starting from different postures performed bilaterally by healthy individuals. We further explore the effect of biomechanical constraints on the dimensionality of control space. We are building on top of prior work showing that muscle activity profiles can be explained by applied moments about the limb joints that reflect the biomechanical constraints. These muscle torques derived from motion capture represent the combined actions of muscle contractions that are under the control of the nervous system. Here we test the generalizability of the relationship between muscle torques and muscle activity profiles across different starting positions and between limbs. We also test a hypothesis that the dimensionality of control space is shaped by biomechanical constraints. We used principal component analysis to evaluate the contribution of individual muscles to producing muscle torques across different workspaces and in both dominant and non-dominant limbs. Results generalize and support the hypothesis. We show that the muscle torques that support the limb against gravity are produced by more consistent combinations of muscle co-contraction than those that produce propulsion. This effect was the strongest in the non-dominant arm moving in the lateral workspace on one side of the body.

Exploring the Impact of Hand Dominance on Laparoscopic Surgical Skills Development Using Network Models.

BACKGROUND: Laparoscopic surgery demands high precision and skill, necessitating effective training protocols that account for factors such as hand dominance. This study investigates the impact of hand dominance on the acquisition and proficiency of laparoscopic surgical skills, utilizing a novel assessment method that combines Network Models and electromyography (EMG) data. METHODS: Eighteen participants, comprising both medical and non-medical students, engaged in laparoscopic simulation tasks, including peg transfer and wire loop tasks. Performance was assessed using Network Models to analyze EMG data, capturing muscle activity and learning progression. The NASA Task Load Index (TLX) was employed to evaluate subjective task demands and workload perceptions. RESULTS: Our analysis revealed significant differences in learning progression and skill proficiency between dominant and non-dominant hands, suggesting the need for tailored training approaches. Network Models effectively identified patterns of skill acquisition, while NASA-TLX scores correlated with participants' performance and learning progression, highlighting the importance of considering both objective and subjective measures in surgical training. CONCLUSIONS: The study underscores the importance of hand dominance in laparoscopic surgical training and suggests that personalized training protocols could enhance surgical precision, efficiency, and patient outcomes. By leveraging advanced analytical techniques, including Network Models and EMG data analysis, this research contributes to optimizing clinical training methodologies, potentially revolutionizing surgical education and improving patient care.

Patient Outcomes After Peripheral Nerve Injury Depend on Bimanual Dexterity and Preserved Use of the Affected Hand.

BACKGROUND: Little is known about how peripheral nerve injury affects human performance, behavior, and life. Hand use choices are important for rehabilitation after unilateral impairment, but rarely measured, and are not changed by the normal course of rehabilitation and daily life. OBJECTIVE: To identify the relationship between hand use (L/R choices), motor performance, and patient-centered outcomes. METHODS: Participants (n = 48) with unilateral peripheral nerve injury were assessed for hand use via Block Building Task, Motor Activity Log, and Edinburgh Handedness Inventory; dexterity (separately for each hand) via Nine-Hole Peg Test, Jebsen Taylor Hand Function Test, and a precision drawing task; patient-centered outcomes via surveys of disability, activity participation, and health-related quality of life; and injury-related factors including injury cause and affected nerve. Factor Analysis of Mixed Data was used to explore relationships between these variables. The data were analyzed under 2 approaches: comparing dominant hand (DH) versus non-dominant hand (NH), or affected versus unaffected hand. RESULTS: The data were best explained by 5 dimensions. Good patient outcomes were associated with NH performance, DH performance (separately and secondarily to NH performance), and preserved function and use of the affected hand; whereas poor patient outcomes were associated with preserved but unused function of the affected hand. CONCLUSION: After unilateral peripheral nerve injury, hand function, hand usage, and patient life arise from a complex interaction of many factors. To optimize rehabilitation after unilateral impairment, new rehabilitation methods are needed to promote performance and use with the NH, as well as the injured hand.

Effect of Hand Dominance on Radial Artery Spasm and Occlusion: A Prospective Observational Study.

Transradial access has become the most commonly used method for cardiac catheterization. Many medical and technical applications have been proposed to reduce TRA complications. The aim of this study is to examine the effect of hand dominance on radial artery spasm and radial artery occlusionin subjects undergoing CC via TRA. Between April 2020 and August 2022, 1713 subjects who underwent CC via TRA were included in the study. Patient data were obtained in terms of hand dominance of the catheterized side and RAS and RAO during a 1-month follow-up period. RAS was seen in 9.6% of the subjects. The RAS in patients catheterized by the dominant hand was significantly higher than that performed by the non-dominant hand (12 vs 7.8%; P = .004). RAO was seen in 1% of the subjects. RAO was significantly higher in the spasm side than in the no-spasm side (3 vs .8%; P = .009). Hand dominance was determined as an independent predictor of radial artery spasm (P = .006). In our study, RAS and RAO were more common on the dominant hand side than on the non-dominant side. Choosing the non-dominant hand for TRA for CC may reduce the incidence of RAS and RAO.

Analysis of Differences in Single-Joint Movement of Dominant and Non-Dominant Hands for Human-like Robotic Control.

Although several previous studies on laterality of upper limb motor control have reported functional differences, this conclusion has not been agreed upon. It may be conjectured that the inconsistent results were caused because upper limb motor control was observed in multi-joint tasks that could generate different inter-joint motor coordination for each arm. Resolving this, we employed a single wrist joint tracking task to reduce the effect of multi-joint dynamics and examined the differences between the dominant and non-dominant hands in terms of motor control. Specifically, we defined two sections to induce feedback (FB) and feedforward (FF) controls: the first section involved a visible target for FB control, and the other section involved an invisible target for FF control. We examined the differences in the position errors of the tracer and the target. Fourteen healthy participants performed the task. As a result, we found that during FB control, the dominant hand performed better than the non-dominant hand, while we did not observe significant differences in FF control. In other words, in a single-joint movement that is not under the influence of the multi-joint coordination, only FB control showed laterality and not FF control. Furthermore, we confirmed that the dominant hand outperformed the non-dominant hand in terms of responding to situations that required a change in control strategy.

Influence of hand dominance, gender, and body mass index on hand grip strength.

Background: Hand grip strength (HGS) measurements serve as an objective measure of upper extremity function. Reliable hand strength evaluation is vital for assessing treatment effectiveness. Objectives: To determine the influence of hand dominance, gender, and body mass index (BMI) on HGS among university students in Ghana. Method: In our cross-sectional study of 304 participants, height, weight, and BMI were measured using a stadiometer and weighing scale. Hand grip strength was assessed with a dynamometer. We compared HGS in dominant and non-dominant hands for males and females using a paired t-test and analysed the correlation between grip strength and weight, height, and BMI using Pearson's correlation coefficient. Results: The mean HGS for right-hand dominant (RHD) male participants was 35.62 kg (± 7.36) for the right hand compared with 32.84 kg (± 7.36) for the left hand. For females RHD the mean HGS in the right hand was 24.60 kg (± 6.42) compared to 22.12 kg (± 5.37) in the left hand. The mean weight, height and BMI of participants were 62.86 kg (± 10.30), 1.67 m (± 0.09) and 22.9 kg/m2 (± 4.9), respectively. A significant relationship existed between HGS and height (r = 0.492; p < 0.01) as well as HGS and BMI (r = 0.290; p < 0.01). However, no notable connection was found between HGS and weight (r = 0.001; p = 0.982). Conclusion: Hand grip strength was significantly stronger in the dominant hand of both males and females. Clinical implications: Physiotherapists should test HGS objectively and quantitatively for use in disease evaluation, diagnosis, and therapy.

Sticking choices in timpani sight-reading performance.

When sight-reading a score, a timpanist needs to decide in real-time which stick to use to play a specific note while interpreting the musical material. Our main point of inquiry seeks to understand which sticking patterns performers employ and how they are affected by rhythmic stability. This paper analyzes the bi-manual sequencing (i.e., sticking) patterns of 31 timpanists in a sight-reading task. We analyze their results compared to model sticking patterns common in percussion pedagogical literature. Results show that while hand dominance plays an essential role in an individual's sticking pattern, the stability of a rhythmic pattern may also dramatically influence the observed particular sticking strategies. In areas of rhythmic stability, performers largely adhered to one of two conventional sticking patterns in the literature (dominant hand lead & alternating). Where rhythmic patterns became more unstable, the performers separated into diverse sticking groups. Moreover, several performers demonstrated sticking patterns which were hybrids or an inverse of the model sticking patterns, without any impact on the success of their sight-reading abilities. Overall, no two individual performers demonstrated the same sticking pattern. In terms of percussion pedagogy, our findings suggest that performers may benefit from an awareness of the adaptability of model sticking strategies. Lastly, we make the case for further study of rhythmic stability and bi-manual sequencing by locating the difference between notational and aural complexity.

The effects of hand dominance, fatigue, and sex on muscle activation during a repetitive overhead fatiguing task.

Previous studies have shown that the dominant arm is generally stronger and more resistant to fatigue. However, whether there are side differences in shoulder muscle activation during a fatiguing upper limb task, and whether this varies according to sex, is unknown. Thirty right-handed adults (15 females) were recruited to complete two sessions of an overhead repetitive fatiguing task (shoulder flexion between 90 and 135° at 1 Hz), performed in two separate sessions with their dominant arm (DA) and non-dominant arm (NDA) until exhaustion. Electromyographic (EMG) data was collected from 11 shoulder muscles of the moving arm, and their activation amplitude (RMS) and activation variability (SD) were assessed. Results show that time to exhaustion was not affected by arm or by sex. There were some main arm effects on EMG activity amplitude, with higher activity on the DA's pectoralis major (p < 0.001), and on the NDA's middle (p = 0.009) and posterior deltoid (p = 0.001) and infraspinatus (p < 0.001). The pectoralis major was affected by arm and fatigue mostly in males. Their DA's pectoralis major activity amplitude was higher, and the amplitude variability was lower, compared to the NDA, with both parameters showing fatigue-dependent decreases at the NDA only (arm x sex x fatigue: RMS: p = 0.007; SD: p = 0.001). As for females, the DA variability of their lower trapezius was smaller, and that of their subscapularis was higher, compared to the NDA (sex x arm, p = 0.028, p = 0.05). There was also more EMG variability on the supraspinatus' dominant side, and on the posterior deltoid and infraspinatus ND side. Results show an overhead shoulder flexion task dependency on pectoralis major control in males, and on lower trapezius and shoulder girdle stabilizers in females, which could be related to both sex- and gender-based factors. This knowledge can help identify side-specific injury risk factors due to overhead work in males and females, and help determine the appropriateness of implementing sex-specific workplace protocols, including alternating arms as fatigue compensatory and recovery strategies.

The Minimum Clinically Important Difference for the Patient-Rated Wrist Evaluation in Surgical Fixation of Distal Radius Fractures: Does Hand Dominance Make a Difference?

BACKGROUND: Distal radius fractures (DRFs) are common orthopaedic injuries. They can be treated in many ways, but the volar locking plate (VLP) is more frequent. Currently, there is limited information regarding the minimum clinically important difference (MCID) in surgically treated DRFs. The purpose of this study was to calculate MCID values for the Patient-Reported Wrist Evaluation (PRWE) in the setting of VLP-treated DRFs. METHODS: A retrospective review was conducted for patients with isolated, surgically-treated DRFs with a VLP. Exclusions included any concomitant procedure other than a carpal tunnel release, skeletal immaturity, polytrauma, open fracture, or missing PRWE data. MCID was calculated using PRWE, an overall health question, and the anchor-based method. RESULTS: A total of 131 patients were identified. Approximately 54.2% injured their dominant hand. AO/OTA classification 23C was the most common (n=89, 67.9%). Average baseline, 6-week, and 12-week PRWE were 71.8 ± 19.6, 34.3 ± 20.1, and 21.2 ± 18.0 respectively. This corresponds to an average change from baseline PRWE at 6 weeks and 12 weeks of -37.5 ± 23.4 and -50.6 ± 22.3, respectively. Average MCID values for 6 weeks and 12 weeks were 43.1 ± 18 and 56.0 ± 20.0, respectively (p<0.001). Hand dominance did not correlate with MCID value (rs = 0.084 at six weeks, rs = 0.099 at 12 weeks). MCID value additionally did not correlate with sex, AO/OTA classification, smoking status, ASA score, or BMI. Treatment at a level 1 trauma center and diagnosis of anxiety and/or depression correlated with a higher 6-week MCID value (rs = 0.308 and rs = 0.410, respectively). Increasing age weakly correlated with higher 12-week MCID value (rs = 0.352). CONCLUSIONS: This study demonstrated an MCID calculation using an overall health anchor. MCID value varied with follow-up time and correlated weakly with age, diagnosis of anxiety and/or depression, and treatment facility, but it did not correlate with injury of the dominant hand. Future research should analyze how to apply MCID and identify successful treatment in the setting of DRF care.

vHIT results with the synapsis system according to clinicians' dominant hand use.

BACKGROUND/OBJECTIVE: There exists limited information in the literature on dominant hand preference in relation with vHIT applications. The present study aimed to examine the relationship between the clinician's dominant use of right- or left-hand and vHIT results. METHODS: A Synapsys vHIT Ulmer device was used in the study. The tests were administered by 3 clinicians experienced in vHIT, 2 of whom were right-handed and 1 left-handed. The test was applied to the 94 participants three times, one week apart. RESULTS: In this study, the correlation between right-handed clinicians and left-handed clinicians was examined, and in all SCCs, namely RA, LA, RL, LL, RP and LP, a moderate positive significant correlation was found between right-handed1 and right-handed2, between right-handed1 and left-handed, and between right-handed2 and left-handed. CONCLUSIONS: In this study, these findings suggested that measures were reliable across test sessions regardless of hand dominancy (right or left). Based on the vHIT results we obtained with three different right- or left-handed clinicians, the clinician should evaluate the results according to the dominant side.

Anatomical aberration of palmaris longus agenesis muscle through clinical examination in relation to gender and hand dominance.

OBJECTIVE: To determine the frequency of agenesis of palmaris longus muscle and its association with gender and hand dominance. METHODS: The cross-sectional descriptive study was conducted at the Bahria University Medical and Dental College, Karachi, from March 2021 to November 2021, and comprised medical students of either gender from 1st, 2nd and 3rd year of studies. Clinical examination of palmaris longus was done by using the classic Schaeffer's test, and it was confirmed using the Thompson's test. The agenesis of palmaris longus muscle and its association with gender and hand dominance was also tested. Data was analysed using SPSS 23. RESULTS: Of the 200 participants, 114(57%) were female and 86(43%) were male. The overall age range was 18-23 years. Of the total, 195(97.5%) subjects were right hand dominant and 5(2.5%) were left hand dominant. Agenesis was found in 67(33.5%) subjects with no significant difference in terms of gender or hand dominance (p>0.05). Statistically significant difference (p=0.01) was found related to bilateral agenesis. CONCLUSIONS: Bilateral agenesis was found significantly more in females compared to the males, while palmaris longus agenesis and hand dominance had no significant association.

Does Laterality Matter? The Effect of Unilateral v. Bilateral Sacroiliac Screw Fixation on Personal Hygiene.

STUDY DESIGN: Retrospective comparative analysis of prospective cohort. OBJECTIVE: To determine whether sacroiliac (SI) screw fixation ipsilateral to hand dominance compared to bilateral fixation impacts personal hygiene (wiping) after toileting. METHODS: Inclusion criteria were adult spinal deformity (ASD) patients with long arthrodesis (≥T12-pelvis) who had undergone primary unilateral or bilateral SI fixation with a minimum of 2-years-follow-up. RESULTS: 117 consecutive patients were included and separated into 2 groups: bilateral SI fixation (BL, n = 61) and unilateral SI fixation (UNI, n = 56), with no difference in age. Of UNI patients, 10.7% (6) performed personal hygiene with a different hand after surgery, compared to 6.6% (4) of patients who received BL fixation (P = 0.422). All UNI patients who switched hands were right-hand dominant, and 5/6 received right-sided fixation. There was no statistical difference found between number of levels fused (<8, 9-11, or >11 levels) and changes in personal hygiene habits. Over a third of patients from both groups had difficulty performing personal hygiene after fusion (UNI = 39.3% BL = 36.1%, P = 0.719). CONCLUSION: SI screws increase the difficulty of performing personal hygiene; yet, the side of unilateral screws does not significantly change personal hygiene habits when compared to bilateral screw placement. Moreover, the length of the construct does not have a significant impact on ability to perform personal hygiene, cause changes in habits, or require the assistance of another individual. However, among our sample of individuals, bilateral fixation did result in a higher rate of revision instrumentation.

Biosignal processing methods to explore the effects of side-dominance on patterns of bi- and unilateral standing stability in healthy young adults.

We examined the effects of side-dominance on the laterality of standing stability using ground reaction force, motion capture (MoCap), and EMG data in healthy young adults. We recruited participants with strong right (n = 15) and left (n = 9) hand and leg dominance (side-dominance). They stood on one or two legs on a pair of synchronized force platforms for 50 s with 60 s rest between three randomized stance trials. In addition to 23 CoP-related variables, we also computed six MoCap variables representing each lower-limb joint motion time series. Moreover, 39 time- and frequency-domain features of EMG data from five muscles in three muscle groups were analyzed. Data from the multitude of biosignals converged and revealed concordant patterns: no differences occurred between left- and right-side dominant participants in kinetic, kinematic, or EMG outcomes during bipedal stance. Regarding single leg stance, larger knee but lower ankle joint kinematic values appeared in left vs right-sided participants during non-dominant stance. Left-vs right-sided participants also had lower medial gastrocnemius EMG activation during non-dominant stance. While right-side dominant participants always produced larger values for kinematic data of ankle joint and medial gastrocnemius EMG activation during non-dominant vs dominant unilateral stance, this pattern was the opposite for left-sided participants, showing larger values when standing on their dominant vs non-dominant leg, i.e., participants had a more stable balance when standing on their right leg. Our results suggest that side-dominance affects biomechanical and neuromuscular control strategies during unilateral standing.

The Effect of Hand Dominance, Age, Gender, Fracture Comminution and ASA Status on Time to Fracture Healing Following Surgical Fixation of Distal Radius Fractures.

Background: There is recent renewed interest in the effect of hand dominance on distal radius fractures. Current studies focus on functional or patient-reported outcomes, with lack of studies pertaining to radiological outcomes. The primary aim of this study is to examine the effect of hand dominance on time to fracture healing following surgical fixation of distal radius fracture. We also looked at the effect of age, gender, fracture comminution and American Society of Anaesthesiologists (ASA) status on time to fracture healing. Methods: Patients who underwent distal radius fracture fixation surgery in our department from 1 January 2015 to 31 December 2015 were included. Time to fracture healing was taken from the day of surgery to when radiographic union was present as evidence by bridging callus or osseous bone. We looked at the effect of hand dominance, age, gender, fracture comminution and ASA status on time to fracture healing. Results: One hundred and forty-five consecutive patients (80 females and 65 males) had a mean period of 56.2 ± 41.8 days to fracture healing post-operatively. Patients with dominant hand injury had a shorter duration to fracture healing than patients with non-dominant hand injury (mean 47.3 ± 31.1 days versus 62.1 ± 46.8 days, p = 0.023). Patients ≥ 65 years and with pre-existing medical conditions (ASA Class II and above) had a longer duration to fracture healing (mean 63.7 ± 53.0 days versus 51.9 ± 33.4 days, p = 0.036 and mean 47.9 ± 30.0 days versus 62.0 ± 47.7 days, p = 0.016, respectively). In addition, patients with comminuted fractures took longer to heal than patients with non-comminuted fractures (mean 57.6 ± 33.4 days versus 48.3 ± 20.8 days, p = 0.038). Conclusion: Time to fracture healing post distal radius fracture fixation surgery was significantly related to hand dominance, as well as age, ASA classification and fracture configuration. Dominant wrist injuries had shorter time to fracture healing. Level of Evidence: Level IV (Therapeutic).

Risk factors for residual pain after ligament reconstruction and tendon interposition on osteoarthritis of the first carpometacarpal joint.

BACKGROUND: Ligament reconstruction and tendon interposition (LRTI) is currently the most performed procedure for osteoarthritis (OA) of the thumb carpometacarpal (CMC) joint. In general, satisfactory outcomes are expected, although some patients complain of residual pain after LRTI. The objective of this study is to determine the factors associated with residual pain. METHOD: All patients with OA of the thumb CMC joint who underwent LRTI at our hospital between October 2013 and October 2018 and were regularly observed for at least 1 year were included. The following variables were extracted and included in the univariate analysis: sex, age, dominant hand, pain visual analog scale (VAS) score, Eaton classification, grip strength, pulp pinch strength, and metacarpophalangeal joint hyperextension angle were recorded as variables. Mann-Whitney U test or Fisher exact test was used for univariate analysis of the above factors, and then multivariate logistic regression analysis was performed to find out the factors associated with residual pain. RESULTS: The study included 60 thumbs of 53 patients. Eleven thumbs had postoperative residual pain. The surgery on the dominant hand was significantly associated with the presence of postoperative residual pain, especially in males. CONCLUSIONS: Dominant hand was associated with residual pain after LRTI for OA of the thumb CMC joint, although residual pain was minimal. Our findings will help in preoperative and postoperative counseling of patients. In the future, our results may also help select surgical procedures according to the patient's characteristics.

Prevalence of inter-arm blood pressure difference among young healthy adults: Results from a large cross-sectional study on 3235 participants.

More than 100 years ago, the difference in blood pressure (BP) between arms was first reported. Recent studies have shown that different blood pressure between the right and left arm leads to cardiovascular events. Three thousand and thirty volunteers participated in our cross-sectional study. The sIABP was equal in 163 of 3030 persons (5.37%), dIABP was equal in 222 out of 3030 persons (7.32%), from a total of 792/3030 persons (26.1%) sIAD >10 mmHg, and dIAD > or = 10 mmHg was found in 927 out of 3030 persons (33.5%) in the right arm, and 32.4% in the left arm. In 2692 of 3030 volunteers BP, initially recorded in the dominant hand (right arm), showing sIAD > or = 10 mmHg was found in 943 (37.1%) volunteers, and when the first measurement was done in 338 left-handed volunteers it showed sIAD > or = 10 mmHg in 112 of 338 (34.1%), P < .001; 95% confidence interval for systolic right hand were (115.73: 116.73), and for systolic left hand 95% confidence interval were (113.17:114.15). Furthermore, height, residential area, and heart rate above 90 bpm had a significant effect on IAD (P = . 041, 0.002, <001, respectively). In conclusion, significant inter-arm systolic and diastolic BP differences above (10 mm Hg) is common in the young, healthy population. Hand dominance is a significant consideration while measuring blood pressure. It is mandatory to measure blood pressure in both arms in a sitting position with a stable condition.

Prevalence of Rotator Cuff Tears Among Older Tennis Players and Its Impact on Clinical Findings and Shoulder Function.

CONTEXT: Tennis is a noncontact sport playable at an individual's own pace. Thus, it is popular among the older adults. It is known that older adults often suffer from rotator cuff tears (RCTs), which may affect tennis activity. However, the prevalence and influence of RCTs on tennis play among older players are not well-known. This study aimed to evaluate the prevalence of RCTs in older tennis players and its impact on physical findings and shoulder function. DESIGN: A cross-sectional study. METHODS: Fifty-three tennis players (mean age: 70.7 y; range: 60-83 y) participating in a recreational-level tennis tournament were examined in this study. An ultrasonographic examination of both shoulders was performed to detect RCTs. Relationships between RCTs of the dominant shoulder and clinical findings, shoulder pain, and shoulder function including range of motion, shoulder strength, and Single Assessment Numeric Evaluation score, and Disability of the Arm, Shoulder and Hand-Sports Module score were assessed. RESULTS: RCTs were detected in 19 (36%) dominant shoulders and 6 (11%) nondominant shoulders. Asymptomatic RCTs were detected in 11 (58%) dominant shoulders and 5 (83%) nondominant shoulders. Increased crepitus and more positive results in the empty can test, and infraspinatus test were observed in the dominant shoulders with RCTs than in those without; however, there was no difference in shoulder pain, range of motion; strength; Single Assessment Numeric Evaluation score; and Disability of the Arm, Shoulder and Hand-Sports Module score between the players with and without RCTs. CONCLUSIONS: One-third of the older tennis players in this study had RCTs in the dominant shoulder with some positive physical sign of an RCT. However, shoulder pain and shoulder function did not differ between the players with and without RCTs, suggesting that RCTs had a minor impact on the tennis performance in the participants of this study.

Stress and Strain During Total Joint Arthroplasty Are Not Impacted by Hand Dominance or Operative Laterality in Orthopedic Surgeons.

BACKGROUND: Orthopedic surgeons experience significant musculoskeletal pain and work-related injuries while performing total joint arthroplasty (TJA). We sought to investigate the impact of operative extremity and surgeon limb dominance on surgeon physiologic stress and energy expenditure during TJA. METHODS: This was a prospective cohort study conducted at a tertiary academic practice. Cardiorespiratory data was recorded continuously in 3 high-volume arthroplasty surgeons using a smart garment that measured heart rate (HR), HR variability, respiratory rate, minute ventilation, and energy expenditure (calories) during conventional total knee (TKA) and total hip arthroplasty (THA). RESULTS: Surgeon 1 and 2 (right-handed) performed 21 right TKAs, 10 left TKAs, 13 right THAs, and 10 left THAs. Surgeon 3 (left-handed) performed 6 right TKAs, 9 left TKAs, 16 right THAs, and 10 left THAs. While performing TKA or THA, limb laterality had no significant impact on operative time and no significant differences existed in HR, HR variability, respiratory rate, minute ventilation, or energy expenditure for any right-handed or left-handed surgeons, regardless of the operative limb laterality. While performing TKA, consistently standing on the side of hand dominance was associated with decreased strain and stress, compared to always standing on the operative side. CONCLUSION: This study suggests that surgeon hand dominance and operative limb laterality do not impact energy expenditure or physiologic strain during TJA. However, consistently standing on the side of hand dominance in TKA may lead to decreased physiologic strain and stress during surgery. Further study utilizing wearable technology during TJA may provide orthopedic surgeons with information about modifiable factors that contribute to differences in physiological parameters during surgery.