Sensors for Wheelchair Tennis: Measuring Trunk and Shoulder Biomechanics and Upper Extremity Vibration during Backhand Stroke

This study was the first to compare the differences in trunk/shoulder kinematics and impact vibration of the upper extremity during backhand strokes in wheelchair tennis players and the able-bodied players relative to standing and sitting positions, adopting an electromagnetic system along with wearable tri-axial accelerometers upon target body segments. A total of 15 wheelchair tennis players and 15 able-bodied tennis players enrolled. Compared to players in standing positions, wheelchair players demonstrated significant larger forward trunk rotation in the pre-preparation, acceleration, and deceleration phase. Significant higher trunk angular velocity/acceleration and shoulder flexion/internal rotation angular velocity/acceleration were also found. When able-bodied players changed from standing to sitting positions, significant changes were observed in the degree of forward rotation of the trunk and shoulder external rotation. These indicated that when the functions of the lower limbs and trunk are lacking or cannot be used effectively, “biomechanical solutions” such as considerable reinforcing movements need to be made before the hitting movement. The differences between wheelchair tennis players and able-bodied players in sitting positions could represent the progress made as the wheelchair players evolve from novices to experts. Knowledge about how sport biomechanics change regarding specific disabilities can facilitate safe and inclusive participation in disability sports such as wheelchair tennis.

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The effect of smartphone usage on the upper extremity performance among Saudi Youth, KSA

Romanian Journal of Rhinology ◽

10.2478/rjr-2018-0006 ◽

2018 ◽

Vol 8 (29) ◽

pp. 47-53 ◽

Cited By ~ 2

Author(s):

Mohammed Khalid Alruzayhi ◽

Muath Salman Almuhaini ◽

Akrm Ibrahem Alwassel ◽

Osama Mansour Alateeq

Keyword(s):

Upper Extremity ◽

External Rotation ◽

Elbow Flexion ◽

Pain Scale ◽

Shoulder Abduction ◽

Smartphone Addiction ◽

Awareness Campaign ◽

Pain Scores ◽

Shoulder Flexion ◽

The Impact

Abstract The current study aims to investigate the effect of smartphone usage on the upper extremity performance among Saudi youth. A goniometer to measure the Range of Motion (ROM), the Smartphone Addiction Scale (SAS), McGill Pain scale and Chattanooga stabilizer were used to perform the current study on a sample of 300 university students from Al-Imam Mohammed Bin Saud University. The results have shown that smartphone addiction is negatively correlated to the elbow flexion, shoulder flexion, shoulder extension, shoulder abduction, shoulder adduction, and both shoulder internal and external rotation. Furthermore, the results have shown that McGill pain scores were positively correlated to elbow flexion, shoulder flexion, shoulder extension, shoulder abduction, shoulder adduction, and both shoulder internal and external rotation. The study has concluded that smartphone usage among Saudi youth negatively affects the upper extremity and causes a significant increase in the pain intensity. The study has recommended that there is an urgent need for a significant awareness campaign to warn the community regarding the impact of using smartphones for long periods of time.

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Effects of Hip Abduction Fatigue on Trunk and Shoulder Kinematics During Throwing and Passive Hip Rotational Range of Motion

Journal of Sport Rehabilitation ◽

10.1123/jsr.2017-0182 ◽

2019 ◽

Vol 28 (4) ◽

pp. 304-310 ◽

Cited By ~ 1

Author(s):

Gretchen D. Oliver ◽

Jessica K. Washington ◽

Sarah S. Gascon ◽

Hillary A. Plummer ◽

Rafael F. Escamilla ◽

...

Keyword(s):

Range Of Motion ◽

Upper Extremity ◽

Repeated Measures ◽

External Rotation ◽

Convenience Sample ◽

Fatigue Protocol ◽

Hip Abduction ◽

Hip Abductor ◽

Overhead Throwing ◽

Shoulder Kinematics

Context:Hip abductor musculature contributes to the stability of the pelvis, which is needed for efficient energy transfer from the lower-extremity to the upper-extremity during overhead throwing.Objective:The purpose of this study was to examine the effects of a bilateral hip abduction fatigue protocol on overhead-throwing kinematics and passive hip range of motion.Design:Prospective cohort study.Setting:Controlled laboratory setting.Participants:A convenience sample of 19 collegiate female softball players (20.6 [1.9] y; 169.3 [9.7] cm; 73.2 [11.2] kg).Main Outcome Measures:Repeated hip abduction to fatigue was performed on an isokinetic dynamometer for 3 consecutive days. Trunk and shoulder kinematics during throwing and hip internal and external rotation range of motion were analyzed prior to fatigue on day 1 (prefatigue) and following fatigue on day 3 (postfatigue).Results:Repeated-measures analysis of variances revealed no statistically significant differences in trunk and shoulder kinematics prefatigue and postfatigue. A statistically significant time × side × direction interaction (F2,36 = 5.462,P = .02,) was observed in hip passive range of motion. A decrease in throwing-side hip internal rotation prefatigue to postfatigue (mean difference = −2.284; 95% confidence interval, −4.302 to −0.266;P = .03) was observed.Conclusions:The hip abductor fatigue protocol used in this study did not significantly alter trunk and upper-extremity throwing kinematics. The lack of changes may indicate that fatigue of the hip abductors does not contribute to trunk and shoulder kinematics during throwing or the protocol may not have been sport-specific enough to alter kinematics.

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Identifying a Connection Between Mobility Degree, Balance, Strength, and Tennis Serve: a Pilot Study

GYMNASIUM ◽

10.29081/gsjesh.2018.19.2.12 ◽

2019 ◽

Vol XIX (2) ◽

pp. 130

Author(s):

Rodica Prodan ◽

Emilia Florina Grosu ◽

Cornelia Popovici ◽

Vlad Teodor Grosu

Keyword(s):

Rotation Angle ◽

External Rotation ◽

Pearson Correlation ◽

Lower Limbs ◽

Pearson Correlation Coefficient ◽

Reasonable Expectation ◽

Tennis Players ◽

Independent Variables ◽

Tennis Serve ◽

Individual Capacity

Tennis serve is the only hit that depends exclusively on the hitter. This aspect leads to the necessity of identification and understanding of the importance of all the elements. The hypothesis is that serve speed is predictable by force of upper and lower limbs. A group of 24 amateur young tennis players, (age of 14 ±2) was subjected to a series of mobility, balance, strength and serve speed testing. The Pearson correlation coefficient was used to identify connections between serve speed, considered as a dependent variable, and mobility, balance, and strength, as independent variables. The hip external rotation angle of the non-dominant arm, one-leg jumps, and one arm ball throws have shown strong positive associations with serve speed (p < 0.05). The anticipation of serve speed had an 81% variance of precision. A combination of body mobility and force may lead to the reasonable expectation the serve speed individual capacity.

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The Relationship Between Maximum Isometric Strength and Ball Velocity in the Tennis Serve

Journal of Human Kinetics ◽

10.1515/hukin-2016-0028 ◽

2016 ◽

Vol 53 (1) ◽

pp. 63-71 ◽

Cited By ~ 11

Author(s):

Ernest Baiget ◽

Francisco Corbi ◽

Juan Pedro Fuentes ◽

Jaime Fernández-Fernández

Keyword(s):

Internal Rotation ◽

External Rotation ◽

Body Height ◽

Isometric Strength ◽

Tennis Players ◽

Shoulder Flexion ◽

Flexion Extension ◽

Ball Velocity ◽

Tennis Serve ◽

The Relationship

AbstractThe aims of this study were to analyze the relationship between maximum isometric strength levels in different upper and lower limb joints and serve velocity in competitive tennis players as well as to develop a prediction model based on this information. Twelve male competitive tennis players (mean ± SD; age: 17.2 ± 1.0 years; body height: 180.1 ± 6.2 cm; body mass: 71.9 ± 5.6 kg) were tested using maximum isometric strength levels (i.e., wrist, elbow and shoulder flexion and extension; leg and back extension; shoulder external and internal rotation). Serve velocity was measured using a radar gun. Results showed a strong positive relationship between serve velocity and shoulder internal rotation (r = 0.67; p < 0.05). Low to moderate correlations were also found between serve velocity and wrist, elbow and shoulder flexion – extension, leg and back extension and shoulder external rotation (r = 0.36 – 0.53; p = 0.377 – 0.054). Bivariate and multivariate models for predicting serve velocity were developed, with shoulder flexion and internal rotation explaining 55% of the variance in serve velocity (r = 0.74; p < 0.001). The maximum isometric strength level in shoulder internal rotation was strongly related to serve velocity, and a large part of the variability in serve velocity was explained by the maximum isometric strength levels in shoulder internal rotation and shoulder flexion.

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Nerve graft versus nerve transfer for neonatal brachial plexus: shoulder outcomes

Journal of Neurosurgery Pediatrics ◽

10.3171/2020.6.peds2027 ◽

2021 ◽

Vol 27 (1) ◽

pp. 87-92

Author(s):

Brandon W. Smith ◽

Kate W. C. Chang ◽

Sravanthi Koduri ◽

Lynda J. S. Yang

Keyword(s):

Brachial Plexus ◽

Clinical Data ◽

External Rotation ◽

Nerve Transfer ◽

Shoulder Function ◽

Nerve Transfers ◽

Shoulder Flexion ◽

Significant Difference ◽

Transfer Strategies ◽

Shoulder External Rotation

OBJECTIVEThe decision-making in neonatal brachial plexus palsy (NBPP) treatment continues to have many areas in need of clarification. Graft repair was the gold standard until the introduction of nerve transfer strategies. Currently, there is conflicting evidence regarding outcomes in patients with nerve grafts versus nerve transfers in relation to shoulder function. The objective of this study was to further define the outcomes for reconstruction strategies in NBPP with a specific focus on the shoulder.METHODSA cohort of patients with NBPP and surgical repairs from a single center were reviewed. Demographic and standard clinical data, including imaging and electrodiagnostics, were gathered from a clinical database. Clinical data from physical therapy evaluations, including active and passive range of motion, were examined. Statistical analysis was performed on the available data.RESULTSForty-five patients met the inclusion criteria for this study, 19 with graft repair and 26 with nerve transfers. There were no significant differences in demographics between the two groups. Understandably, there were no patients in the nerve grafting group with preganglionic lesions, resulting in a difference in lesion type between the cohorts. There were no differences in preoperative shoulder function between the cohorts. Both groups reached statistically significant improvements in shoulder flexion and shoulder abduction. The nerve transfer group experienced a significant improvement in shoulder external rotation, from −78° to −28° (p = 0.0001), whereas a significant difference was not reached in the graft group. When compared between groups, there appeared to be a trend favoring nerve transfer in shoulder external rotation, with the graft patients improving by 17° and the transfer patients improving by 49° (p = 0.07).CONCLUSIONSIn NBPP, patients with shoulder weakness experience statistically significant improvements in shoulder flexion and abduction after graft repair or nerve transfer, and patients with nerve transfers additionally experience significant improvement in external rotation. With regard to shoulder external rotation, there appear to be some data supporting the use of nerve transfers.

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Gender Differences in Kinematic Analysis of the Lower Limbs during the Chasse Step in Table Tennis Athletes

Healthcare ◽

10.3390/healthcare9060703 ◽

2021 ◽

Vol 9 (6) ◽

pp. 703

Author(s):

Xiaoyi Yang ◽

Yuqi He ◽

Shirui Shao ◽

Julien S. Baker ◽

Bíró István ◽

...

Keyword(s):

Female Athletes ◽

External Rotation ◽

Rotational Velocity ◽

Knee Extension ◽

Lower Limbs ◽

Table Tennis ◽

Male Athletes ◽

Analysis System ◽

Hip Flexion ◽

Hip Internal Rotation

The chasse step is one of the most important footwork maneuvers used in table tennis. The purpose of this study was to investigate the lower limb kinematic differences of table tennis athletes of different genders when using the chasse step. The 3D VICON motion analysis system was used to capture related kinematics data. The main finding of this study was that the step times for male athletes (MA) were shorter in the backward phase (BP) and significantly longer in the forward phase (FP) than for female athletes (FA) during the chasse step. Compared with FA, knee external rotation for MA was larger during the BP. MA showed a smaller knee flexion range of motion (ROM) in the BP and larger knee extension ROM in the FP. Moreover, hip flexion and adduction for MA were significantly greater than for FA. In the FP, the internal rotational velocity of the hip joint was significantly greater. MA showed larger hip internal rotation ROM in the FP but smaller hip external rotation ROM in the BP. The differences between genders can help coaches personalize their training programs and improve the performance of both male and female table tennis athletes.

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Lumbopelvic Control and the Development of Upper Extremity Injury in Professional Baseball Pitchers

The American Journal of Sports Medicine ◽

10.1177/0363546520988122 ◽

2021 ◽

pp. 036354652098812

Author(s):

Kevin Laudner ◽

Regan Wong ◽

Daniel Evans ◽

Keith Meister

Keyword(s):

Upper Extremity ◽

Lower Limbs ◽

Group Differences ◽

Professional Baseball ◽

Extremity Injury ◽

Level Of Evidence ◽

Balance Task ◽

Upper Extremity Injury ◽

Baseball Pitchers ◽

Extremity Injuries

Background: The baseball-throwing motion requires a sequential order of motions and forces initiating in the lower limbs and transferring through the trunk and ultimately to the upper extremity. Any disruption in this sequence can increase the forces placed on subsequent segments. No research has examined if baseball pitchers with less lumbopelvic control are more likely to develop upper extremity injury than pitchers with more control. Purpose: To determine if baseball pitchers who sustain a chronic upper extremity injury have less lumbopelvic control before their injury compared with a group of pitchers who do not sustain an injury. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 49 asymptomatic, professional baseball pitchers from a single Major League Baseball organization participated. Lumbopelvic control was measured using an iPod-based digital level secured to a Velcro belt around each player’s waist to measure anteroposterior (AP) and mediolateral (ML) deviations (degrees) during single-leg balance with movement and static bridge maneuvers. During a competitive season, 22 of these pitchers developed upper extremity injuries, while the remaining 27 sustained no injuries. Separate 2-tailed t-tests were run to determine if there were significant differences in lumbopelvic control between groups ( P < .05). Results: There were no significant between-group differences for the stride leg (nondominant) during the bridge test in either the AP ( P = .79) or the ML ( P = .42) directions, or either direction during the drive leg bridge test ( P > .68). However, the injured group had significantly less lumbopelvic control than the noninjured group during stride leg balance in both the AP ( P = .03) and the ML ( P = .001) directions and for drive leg balance in both the AP ( P = .01) and the ML ( P = .04) directions. Conclusion: These results demonstrate that baseball pitchers with diminished lumbopelvic control, particularly during stride leg and drive leg single-leg balance with movement, had more upper extremity injuries than those with more control. Clinicians should consider evaluating lumbopelvic control in injury prevention protocols and provide appropriate exercises for restoring lumbopelvic control before returning athletes to competition after injury. Specific attention should be given to testing and exercises that mimic a single-limb balance task.

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Optimizing the Explosive Force of the Elite Level Football-Tennis Players through Plyometric and Specific Exercises

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18158228 ◽

2021 ◽

Vol 18 (15) ◽

pp. 8228

Author(s):

Anamaria Gherghel ◽

Dana Badau ◽

Adela Badau ◽

Liviu Moraru ◽

Gabriel Marian Manolache ◽

...

Keyword(s):

Dynamic Balance ◽

Lower Limbs ◽

Experimental Program ◽

Jump Height ◽

Balance Study ◽

Athletic Program ◽

Tennis Players ◽

Average Value ◽

Explosive Force ◽

Vertical Jumps

The aim of the research was to implement an athletic program to improve the explosive force in order to optimize physical fitness at the level of elite football-tennis players and evaluate the progress made through specific tests using the Opto Jump. The research included 10 elite European and world-class players, on whom an experimental program was applied in order to improve the explosive force of the limbs in conditions of speed, endurance, and dynamic balance. Study tests: five vertical jumps on the spot, on the left/right leg; five back and forth jumps on the left/right leg; five left/right side jumps on the left/right leg; vertical jumps on both legs 60 s; BFS vertical jumps. For each test, the following parameters specific to the explosive force were statistically analyzed: contact time (s); flight time (s); jump height (cm), jump power (w/kg); RSI—Reactive Strength Index, defined as Height (m/s). In the study, the average value of the parameters specific to the jumps performed in each test was taken into account. During the study, the tests were performed and processed on the Opto Jump device and software. In all tests of the experiment monitored through Opto Jump, significant progress was made in the final test compared to the initial one, which demonstrates the efficiency of the physical training program implemented for the development of explosive force, with an impact on the sports performance of elite players. The most relevant results obtained for the left leg regarding the improvement of the explosive force of the lower limbs materialized in the jump height parameter was in the test of five vertical jumps on one leg on the spot, and for the right leg in the tests of: five back and forth jumps and five left/right side jumps. The most significant advances in the study were in the tests, in descending order of their weight: 60 s vertical jumps on both legs; five back-and-forth jumps and five left/right side jumps, five vertical jumps on one leg standing, and BFS vertical jumps.

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Evidence That the Superior Colliculus Participates in the Feedback Control of Saccadic Eye Movements

Journal of Neurophysiology ◽

10.1152/jn.00886.2000 ◽

2002 ◽

Vol 87 (2) ◽

pp. 679-695 ◽

Cited By ~ 91

Author(s):

Robijanto Soetedjo ◽

Chris R. S. Kaneko ◽

Albert F. Fuchs

Keyword(s):

Superior Colliculus ◽

Firing Rate ◽

Saccadic Eye Movements ◽

Burst Duration ◽

Saccadic Amplitude ◽

Optimal Vector ◽

Deceleration Phase ◽

Acceleration And Deceleration ◽

Motor Error ◽

Saccade Duration

There is general agreement that saccades are guided to their targets by means of a motor error signal, which is produced by a local feedback circuit that calculates the difference between desired saccadic amplitude and an internal copy of actual saccadic amplitude. Although the superior colliculus (SC) is thought to provide the desired saccadic amplitude signal, it is unclear whether the SC resides in the feedback loop. To test this possibility, we injected muscimol into the brain stem region containing omnipause neurons (OPNs) to slow saccades and then determined whether the firing of neurons at different sites in the SC was altered. In 14 experiments, we produced saccadic slowing while simultaneously recording the activity of a single SC neuron. Eleven of the 14 neurons were saccade-related burst neurons (SRBNs), which discharged their most vigorous burst for saccades with an optimal amplitude and direction (optimal vector). The optimal directions for the 11 SRBNs ranged from nearly horizontal to nearly vertical, with optimal amplitudes between 4 and 17°. Although muscimol injections into the OPN region produced little change in the optimal vector, they did increase mean saccade duration by 25 to 192.8% and decrease mean saccade peak velocity by 20.5 to 69.8%. For optimal vector saccades, both the acceleration and deceleration phases increased in duration. However, during 10 of 14 experiments, the duration of deceleration increased as fast as or faster than that of acceleration as saccade duration increased, indicating that most of the increase in duration occurred during the deceleration phase. SRBNs in the SC changed their burst duration and firing rate concomitantly with changes in saccadic duration and velocity, respectively. All SRBNs showed a robust increase in burst duration as saccadic duration increased. Five of 11 SRBNs also exhibited a decrease in burst peak firing rate as saccadic velocity decreased. On average across the neurons, the number of spikes in the burst was constant. There was no consistent change in the discharge of the three SC neurons that did not exhibit bursts with saccades. Our data show that the SC receives feedback from downstream saccade-related neurons about the ongoing saccades. However, the changes in SC firing produced in our study do not suggest that the feedback is involved with producing motor error. Instead, the feedback seems to be involved with regulating the duration of the discharge of SRBNs so that the desired saccadic amplitude signal remains present throughout the saccade.

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Internal- and External-Rotation Peak Torque in Little League Baseball Players With Subacromial Impingement Syndrome: Improved by Closed Kinetic Chain Shoulder Training

Journal of Sport Rehabilitation ◽

10.1123/jsr.2014-0333 ◽

2016 ◽

Vol 25 (3) ◽

pp. 263-265 ◽

Cited By ~ 4

Author(s):

Dong-Rour Lee ◽

Laurentius Jongsoon Kim

Keyword(s):

Angular Velocity ◽

External Rotation ◽

Peak Torque ◽

Subacromial Impingement Syndrome ◽

Subacromial Impingement ◽

Kinetic Chain ◽

Baseball Players ◽

Little League ◽

Youth Baseball ◽

Closed Kinetic Chain

Context:Many studies have explored closed kinetic chain (CKC) shoulder exercises (SEs) with a sling because they are safer and more effective than open-chain exercises, especially in early stages of treatment. However, the application of CKC SE in youth baseball players has rarely been attempted, although teenage baseball players also experience shoulder pain.Objective:To investigate the effects of CKC SE on the peak torque of shoulder internal rotation (IR) and external rotation (ER) in youth baseball players.Design:Single-group pretest, posttest.Setting:Biomechanics laboratory.Participants:23 Little League Baseball players with subacromial impingement syndrome.Interventions:The CKC SE with a sling was CKC shoulder-flexion exercise, extension exercise, IR exercise, and ER exercise. This exercise regimen was conducted 2 or 3 times/wk for 8 wk.Main Outcome Measures:The peak torque of shoulder IR and ER was measured using an isokinetic dynamometer. Concentric shoulder rotation was performed, with 5 repetitions at an angular velocity of 60°/s and 15 at 180°/s.Results:The IR and ER peak torque significantly increased at each angular velocity after the exercise program. In particular, the increase in IR and ER peak torque values was statistically significant at an angular velocity of 180°/s.Conclusions:CKC SE was effective in increasing shoulder IR and ER strength, demonstrating its potential benefits in the prevention and treatment of shoulder injury. In addition, increased IR peak torque appears to improve throwing velocity in baseball players.

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