scholarly journals Neck rotation modulates flexion synergy torques, indicating an ipsilateral reticulospinal source for impairment in stroke

2012 ◽  
Vol 108 (11) ◽  
pp. 3096-3104 ◽  
Author(s):  
Michael D. Ellis ◽  
Justin Drogos ◽  
Carolina Carmona ◽  
Thierry Keller ◽  
Julius P. A. Dewald
Keyword(s):  
Reticular Formation ◽  
Muscle Activation ◽  
External Rotation ◽  
Statistical Design ◽  
Head Rotation ◽  
Elbow Flexion ◽  
Shoulder Abduction ◽  
Joint Control ◽  
Age Range ◽  
Flexion Synergy

The effect of reticular formation excitability on maximum voluntary torque (MVT) generation and associated muscle activation at the shoulder and elbow was investigated through natural elicitation (active head rotation) of the asymmetric tonic neck reflex (ATNR) in 26 individuals with stroke and 9 age-range-matched controls. Isometric MVT generation at the shoulder and elbow was quantified with the head rotated (face pointing) contralateral and ipsilateral to the paretic (stroke) and dominant (control) arm. Given the dominance of abnormal torque coupling of elbow flexion with shoulder abduction (flexion synergy) in stroke and well-developed animal models demonstrating a linkage between reticular formation and ipsilateral elbow flexors and shoulder abductors, we hypothesized that constituent torques of flexion synergy, specifically elbow flexion and shoulder abduction, would increase with contralateral head rotation. The findings of this investigation support this hypothesis. Increases in MVT for three of four flexion synergy constituents (elbow flexion, shoulder abduction, and shoulder external rotation) were observed during contralateral head rotation only in individuals with stroke. Electromyographic data of the associated muscle coactivations were nonsignificant but are presented for consideration in light of a likely underpowered statistical design for this specific variable. This study not only provides evidence for the reemergence of ATNR following stroke but also indicates a common neuroanatomical link, namely, an increased reliance on ipsilateral reticulospinal pathways, as the likely mechanism underlying the expression of both ATNR and flexion synergy that results in the loss of independent joint control.

Clinical findings in C5-C6 and C5-C7 root palsies with brachial plexus traction lesions

2012 ◽  
Vol 38 (3) ◽  
pp. 237-241 ◽  
Author(s):  
J. A. Bertelli ◽  
M. F. Ghizoni
Keyword(s):  
Brachial Plexus ◽  
External Rotation ◽  
Elbow Flexion ◽  
Clinical Findings ◽  
Hand Strength ◽  
Shoulder Abduction ◽  
Finger Extension ◽  
Root Injury ◽  
Flexion Extension

Stretch injuries of the C5-C7 roots of the brachial plexus traditionally have been associated with palsies of shoulder abduction/external rotation, elbow flexion/extension, and wrist, thumb, and finger extension. Based on current myotome maps we hypothesized that, as far as motion is concerned, palsies involving C5-C6 and C5-C7 root injuries should be similar. In 38 patients with upper-type palsies of the brachial plexus, we examined for correlations between clinical findings and root injury level, as documented by CT tomomyeloscan. Contrary to commonly held beliefs, C5-C7 root injuries were not associated with loss of extension of the elbow, wrist, thumb, or fingers, but residual hand strength was much lower with C5-C7 vs C5-C6 lesions.

scholarly journals Effect of Pitching Consecutive Days in Youth Fast-Pitch Softball Tournaments on Objective Shoulder Strength and Subjective Shoulder Symptoms

2017 ◽  
Vol 45 (6) ◽  
pp. 1413-1419 ◽  
Author(s):  
S. Andrew Skillington ◽  
Robert H. Brophy ◽  
Rick W. Wright ◽  
Matthew V. Smith
Keyword(s):  
Shoulder Pain ◽  
External Rotation ◽  
Elbow Flexion ◽  
Strength Loss ◽  
Complete Recovery ◽  
Progressive Increase ◽  
Shoulder Abduction ◽  
Shoulder Injury ◽  
Level Of Evidence ◽  
Cross Sectional

Background: The windmill pitching motion has been associated with risk for shoulder injury. Because there are no pitching limits on youth fast-pitch softball pitchers, these athletes often pitch multiple games across consecutive days. Strength changes, fatigue levels, and shoulder pain that develop among female fast-pitch pitchers over the course of consecutive days of pitching have not been investigated. Hypothesis: Over the course of 2- and 3-day fast-pitch softball tournaments, pitchers will develop progressive objective weakness and increased subjective shoulder fatigue and pain without complete recovery between days. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Fourteen female fast-pitch softball pitchers between the ages of 14 and 18 years were evaluated for strength and fatigue changes across 2- and 3-day tournaments. At the beginning and end of each day of tournament play, pitchers were asked to quantify shoulder fatigue and shoulder pain levels of their dominant throwing arm using a 10-point visual analog scale (VAS). Shoulder abduction, flexion, external rotation, internal rotation, elbow flexion, and elbow extension strength measurements were gathered using a handheld dynamometer. Results: Over the course of an average single day of tournament participation, pitchers developed significant increases in VAS scores for shoulder fatigue (median, 2.0; 95% CI, 1.3-3.0) and pain (median, 1.3; 95% CI, 0.5-2.3) and significant strength loss in all tested motions. Pitchers also developed significant increases in VAS shoulder fatigue (median, 3.5; 95% CI, 1.5-5.5), VAS shoulder pain (median, 2.5; 95% CI, 1.0-4.5), and strength loss in all tested motions over the entire tournament. Shoulder pain, fatigue, and strength do not fully recover between days. The accumulation of subjective shoulder pain and fatigue over the course of tournament play were closely correlated. Conclusion: Among youth female fast-pitch softball pitchers, there is a progressive increase in shoulder fatigue, pain, and weakness over the course of 2- and 3-day tournaments without full recovery between consecutive days of pitching.

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

2018 ◽  
Vol 8 (29) ◽  
pp. 47-53 ◽  
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.

Neurolysis alone as the treatment for neuroma-in-continuity with more than 50% conduction in infants with upper trunk brachial plexus birth palsy

2014 ◽  
Vol 13 (2) ◽  
pp. 229-237 ◽  
Author(s):  
Emily Andrisevic ◽  
Marshall Taniguchi ◽  
Michael D. Partington ◽  
Julie Agel ◽  
Ann E. Van Heest
Keyword(s):  
Brachial Plexus ◽  
External Rotation ◽  
Severe Disease ◽  
Treatment Algorithm ◽  
Elbow Flexion ◽  
Functional Improvement ◽  
Shoulder Abduction ◽  
Active Movement ◽  
Nerve Injuries

Object The debate addressed in this article is that of surgical treatment methods for a neuroma-in-continuity. The authors of this study chose to test the hypothesis that more severe nerve injuries, as distinguished by < 50% conduction across a neuroma-in-continuity, could be treated with neuroma resection and grafting, whereas less severe nerve injuries, with > 50% conduction across the neuroma, could be treated with neurolysis alone. Methods The goal of this study was to compare preoperative and postoperative Active Movement Scale (AMS) scores in children with upper trunk brachial plexus birth injuries treated with neurolysis alone if the neuroma's conductivity was > 50% on intraoperative nerve testing. Seventeen patients (7 male, 10 female) met the criteria for inclusion in this study. Surgery was done when the patients were an average of 10 months old (range 6–19 months). The authors analyzed AMS scores from the preoperative assessment, 1-year postoperative follow-up visit, and subsequent follow-up assessment as close to 3 years after surgery as possible (referred to in this paper as > 2-year postoperative scores). Results Comparison of preoperative and 1-year follow-up data showed significant improvement in shoulder abduction, flexion, external rotation, and internal rotation; elbow flexion and supination; and wrist extension. Comparison of preoperative findings and results of assessment at > 2-year follow-up showed significant improvement in shoulder abduction, flexion, external rotation; and elbow flexion and supination. At final follow-up, useful function (AMS score of 6 or 7) was achieved for elbow flexion in 14 of 16 patients, shoulder flexion in 11 of 15 patients, shoulder abduction in 11 of 16 patients, and shoulder external rotation in 5 of 15 patients. Conclusions This report indicates that there is a subgroup of patients who can benefit clinically, with functional improvement of shoulder and elbow function, from treatment with neurolysis alone for upper trunk lesions demonstrating more than 50% conduction across the neuroma on intraoperative nerve testing. Patients with less than 50% conduction, indicating more severe disease, are treated with nerve resection and grafting in the authors' treatment algorithm.

Navigating the gray zone: a guideline for surgical decision making in obstetrical brachial plexus injuries

2009 ◽  
Vol 3 (3) ◽  
pp. 173-180 ◽  
Author(s):  
James R. Bain ◽  
Carol DeMatteo ◽  
Deborah Gjertsen ◽  
Robert D. Hollenberg
Keyword(s):  
Decision Making ◽  
Brachial Plexus ◽  
External Rotation ◽  
Elbow Flexion ◽  
Complete Recovery ◽  
Shoulder Abduction ◽  
Active Movement ◽  
Gray Zone ◽  
Surgical Decision ◽  
Surgical Decision Making

Object In the literature, the best recommendations are imprecise as to the timing and selection of infants with obstetrical brachial plexus injury (OBPI) for surgical intervention. There is a gray zone (GZ) in which the decision as to the benefits and risks of surgery versus no surgery is not clear. The authors propose to describe this category, and they have developed a guideline to assist surgical decision-making within this GZ. Methods The authors first performed a critical review of the medical literature to determine the existence of a GZ in other clinical publications. In those reports, 47–89% of infants with OBPI fell within such a GZ. Complete recovery in those reported patients ranged from 9 to 59%. Using a prospective inception cohort design, all infants referred to the OBPI Clinic at McMaster Children's Hospital were systematically evaluated up to 3 years of age. The Active Movement Scale scores were compared for surgical and nonsurgical groups of infants in the GZ to identify any important trends that would guide surgical decision-making. Results In the authors' population of infants with OBPI, 81% fell within the GZ, of whom 44% achieved complete recovery. Mean scores differed significantly between surgery and no surgery groups in terms of total Active Movement Scale score and shoulder abduction and flexion at 6 months. Elbow flexion and external rotation differed at 3 months. Conclusions There is compelling evidence that there is a group of infants with OBPI in whom the assessment of the risk/benefit ratio for surgical versus nonsurgical treatment is not evident. These infants reside within what the authors have called the GZ. Based on their results, a guideline was derived to assist clinicians working with infants with OBPI to navigate the GZ.

scholarly journals Ankle dorsiflexion deficit in the back leg is a risk factor for shoulder and elbow injuries in young baseball players

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hitoshi Shitara ◽  
Tsuyoshi Tajika ◽  
Takuro Kuboi ◽  
Tsuyoshi Ichinose ◽  
Tsuyoshi Sasaki ◽  
...  
Keyword(s):  
Risk Factors ◽  
Ankle Joint ◽  
External Rotation ◽  
Plantar Flexion ◽  
Univariate Analysis ◽  
Elbow Flexion ◽  
Shoulder Abduction ◽  
Baseball Players ◽  
Elbow Injuries ◽  
Ankle Function

AbstractThe relationship between ankle joint function and throwing-related injuries has not been demonstrated. We hypothesized that limited ankle joint range of motion (ROM) was related to risk factors for shoulder and elbow injuries in young baseball players. This 12-month prospective cohort study evaluated the age, height, weight, playing position, shoulder, elbow, and ankle function of 228 enrolled baseball players. Shoulder and elbow injuries were tracked during the season. Univariate and multivariate analyses were performed to identify risk factors for shoulder and elbow injuries among participants divided into non-injured and injured groups. Univariate analysis showed that age, height, weight, ROM of elbow flexion in the dominant arm, muscle strength ratio of shoulder abduction, and the likelihood of being a pitcher or a catcher were significantly greater in the injured group than in the non-injured group. ROM of shoulder abduction-external/internal rotation, shoulder total arc on the dominant arm, ankle joint dorsiflexion, and plantar flexion on the back (non-lead) and front (lead) legs were significantly less in the injured group than in the non-injured group. In conclusion, ROM dorsiflexion deficits in the back leg, shoulder abduction-external rotation in the dominant arm, ROM increase in elbow flexion on the dominant side, older age, and being a pitcher were significant independent risk factors for injury.

scholarly journals The Muscle Activation Differences in Post-Stroke Upper Limb Flexion Synergy Based on Spinal Cord Segments: A Preliminary Proof-of-Concept Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Gang Liu ◽  
Chin-hsuan Chia ◽  
Wei-ning Wang ◽  
Yue Cao ◽  
Shan Tian ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Upper Limb ◽  
Muscle Activation ◽  
Elbow Flexion ◽  
Healthy Controls ◽  
Joint Movement ◽  
Stroke Patients ◽  
Spinal Cord Segment ◽  
Limb Flexion ◽  
Flexion Synergy

Objective: This study examined the activation difference of muscles innervated by cervical cord 5-6 (C5-C6) and cervical cord 8- thoracic cord 1 (C8-T1) in upper limb flexion synergy after stroke.Methods: Surface electromyography (sEMG) signals were collected during elbow flexion in stroke patients and healthy controls. The study compared normalized activation of two pairs of muscles that could cause similar joint movement but which dominated different spinal cord segments (clavicular part of the pectoralis major, PC vs. Sternocostal part of the pectoralis major, PS; Flexor carpi radialis, FCR vs. Flexor carpi ulnaris, FCU). In each muscle pair, one muscle was innervated by the same spinal cord segment (C5-C6), dominating the elbow flexion and the other was not. The comparison of the activation of the same muscle between patients and healthy controls was undertaken after standardization based on the activation of the biceps brachii in elbow flexion.Results: There was no difference between the PC and PS's normalized activation in healthy controls while the PC's normalized activation was higher than PS in stroke patients during elbow flexion. Similarly, there was no significant difference in normalized activation between FCR and FCU in healthy controls, and the same is true for stroke patients. However, the standardized activation of both FCR and FCU in stroke patients was significantly lower than that in healthy controls.Conclusion: After stroke, the activation of the distal muscles of the upper limb decreased significantly regardless of the difference of spinal cord segments; while the activation of the proximal muscles innervated by the same spinal cord segment (C5-C6) dominating the elbow flexion showed higher activation during flexion synergy. The difference in muscle activation based on spinal cord segments may be the reason for the stereotyped joint movement of upper limb flexion synergy.

scholarly journals Upper Extremity and Lower Back Moments during Carrying Tasks in Farm Children

2009 ◽  
Vol 25 (2) ◽  
pp. 149-155 ◽  
Author(s):  
Jason C. Gillette ◽  
Catherine A. Stevermer ◽  
Stacey A. Meardon ◽  
Timothy R. Derrick ◽  
Charles V. Schwab
Keyword(s):  
External Rotation ◽  
Elbow Flexion ◽  
Axial Rotation ◽  
Video Data ◽  
Upper Body ◽  
Shoulder Abduction ◽  
Lateral Bending ◽  
Joint Moments ◽  
Shoulder Flexion ◽  
Shoulder External Rotation

Farm youth commonly perform animal care tasks such as feeding and watering. The purpose of this study was to determine the effects of age, bucket size, loading symmetry, and amount of load on upper body moments during carrying tasks. Fifty-four male and female participants in four age groups (8–10 years, 12–14 years, 15–17 years, and adults, 20–26 years) participated in the study. Conditions included combinations of large or small bucket sizes, unilateral or bilateral loading, and load levels of 10% or 20% of body weight (BW). During bucket carrying, elbow flexion, shoulder flexion, shoulder abduction, shoulder external rotation, L5/S1 extension, L5/S1 lateral bending, and L5/S1 axial rotation moments were estimated using video data. The 8–10 year-old group did not display higher proportional joint moments as compared with adults. Decreasing the load from 20% BW to 10% BW significantly decreased maximum normalized elbow flexion, shoulder flexion, shoulder abduction, shoulder external rotation, L5/S1 lateral bending, and L5/S1 axial rotation moments. Carrying the load bilaterally instead of unilaterally also significantly reduced these six maximum normalized joint moments. In addition, modifying the carrying task by using smaller one-gallon buckets produced significant reductions in maximum L5/S1 lateral bending moments.

Abstract TP147: Quantitative Measures of Strength and Synergy Differentiate Individuals With Chronic Stroke With and Without Clinically Detectable Elbow Contracture

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Grace C Bellinger ◽  
Michael D Ellis
Keyword(s):  
Quantitative Measure ◽  
Chronic Stroke ◽  
Future Research ◽  
Emg Activity ◽  
Shoulder Abduction ◽  
Joint Control ◽  
Elbow Extension ◽  
Unaffected Side ◽  
Elbow Contracture ◽  
Flexion Synergy

Many individuals with chronic stroke demonstrate contracture of the elbow flexors. The development of contracture may be attributable to underlying impairments such as weakness, flexion synergy, and hyperactive reflexes. This study explored differences in motor impairment and function between 17 individuals with clinically detectable elbow flexor contracture and 17 individuals with full passive range of motion. The groups did not differ in age (61.61 ± 7.99, 55.06 ± 12.48, p = 0.078), years post-stroke (12.92 ± 9.34, 10.60 ± 7.16, p = 0.423), or Fugl-Meyer Motor Assessment score (FMA, 26.35 ± 5.86, 26.47 ± 8.70, p = 0.963). The passive range limitation in the contracture group was 3 to 36° (11.65 ± 8.30°). Kinetics, kinematics, and EMG were used to quantify four motor impairments and reaching function. Shoulder abduction and elbow extension strength were measured isometrically and normalized to the unaffected side. Flexion synergy was quantified as a force-based measure assessing independent joint control. Flexor spasticity was quantified while reaching at 50% of maximum shoulder abduction as the change in biceps EMG from reach onset to peak angular velocity, normalized by maximal EMG activity. Reaching function was defined as maximum reaching distance against gravity and normalized by target distance (-10° of full extension). The groups differed in elbow extension strength (Contracture, 0.315 ± 0.129; No contracture, 0.559 ± 0.153; p < 0.001) and flexion synergy (0.146 ± 0.186, 0.397 ± 0.229, p = 0.009). The groups did not differ in shoulder abduction strength (0.500 ± 0.174, 0.615 ± 0.199, p = 0.080), flexor spasticity (0.079 ± 0.090, 0.056 ± 0.115, p = 0.523), or reaching function (0.501 ± 0.391, 0.714 ± 0.296, p = 0.082). The findings of this study suggest a relationship between elbow contracture and the concurrent presence of elbow extension weakness and flexion synergy. The quantitative measure of reaching function will likely differentiate individuals with and without contracture if the assessment is modified so that the standardized reaching target is located at 0° of elbow extension (normal range). Future research should use quantitative metrics to further explore the temporal recovery of impairments in order to prevent the development of contracture.

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