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Journal of Athletic Training Apr 2018Scapular taping can offer clinical benefit to some patients with shoulder pain; however, the underlying mechanisms are unclear. Understanding these mechanisms may...
CONTEXT
Scapular taping can offer clinical benefit to some patients with shoulder pain; however, the underlying mechanisms are unclear. Understanding these mechanisms may guide the development of treatment strategies for managing neuromusculoskeletal shoulder conditions.
OBJECTIVE
To examine the mechanisms underpinning the benefits of scapular taping.
DESIGN
Descriptive laboratory study.
SETTING
University laboratory.
PATIENTS OR OTHER PARTICIPANTS
A total of 15 individuals (8 men, 7 women; age = 31.0 ± 12.4 years, height = 170.9 ± 7.6 cm, mass = 73.8 ± 14.4 kg) with no history of shoulder pain.
INTERVENTION(S)
Scapular taping.
MAIN OUTCOME MEASURE(S)
Surface electromyography (EMG) was used to assess the (1) magnitude and onset of contraction of the upper trapezius (UT), lower trapezius (LT), and serratus anterior relative to the contraction of the middle deltoid during active shoulder flexion and abduction and (2) corticomotor excitability (amplitude of motor-evoked potentials from transcranial magnetic stimulation) of these muscles at rest and during isometric abduction. Active shoulder-flexion and shoulder-abduction range of motion were also evaluated. All outcomes were measured before taping, immediately after taping, 24 hours after taping with the original tape on, and 24 hours after taping with the tape removed.
RESULTS
Onset of contractions occurred earlier immediately after taping than before taping during abduction for the UT (34.18 ± 118.91 milliseconds and 93.95 ± 106.33 milliseconds, respectively, after middle deltoid contraction; P = .02) and during flexion for the LT (110.02 ± 109.83 milliseconds and 5.94 ± 92.35 milliseconds, respectively, before middle deltoid contraction; P = .06). These changes were not maintained 24 hours after taping. Mean motor-evoked potential onset of the middle deltoid was earlier at 24 hours after taping (tape on = 7.20 ± 4.33 milliseconds) than before taping (8.71 ± 5.24 milliseconds, P = .008). We observed no differences in peak root mean square EMG activity or corticomotor excitability of the scapular muscles among any time frames.
CONCLUSIONS
Scapular taping was associated with the earlier onset of UT and LT contractions during shoulder abduction and flexion, respectively. Altered corticomotor excitability did not underpin earlier EMG onsets of activity after taping in this sample. Our findings suggested that the optimal time to engage in rehabilitative exercises to facilitate onset of trapezius contractions during shoulder movements may be immediately after tape application.
Topics: Adult; Deltoid Muscle; Electromyography; Female; Humans; Intermediate Back Muscles; Male; Motor Neurons; Muscle Contraction; Muscle, Skeletal; Range of Motion, Articular; Scapula; Shoulder; Superficial Back Muscles; Surgical Tape
PubMed: 29569944
DOI: 10.4085/1062-6050-68-17 -
World Journal of Clinical Cases Nov 2014The purpose of this review article is to discuss the clinical spectrum of recurrent traumatic anterior shoulder instability with the current concepts and controversies... (Review)
Review
The purpose of this review article is to discuss the clinical spectrum of recurrent traumatic anterior shoulder instability with the current concepts and controversies at the scientific level. Because of increasing participation of people from any age group of the population in sports activities, health care professionals dealing with the care of trauma patients must have a thorough understanding of the anatomy, patho-physiology, risk factors, and management of anterior shoulder instability. The risk factors for recurrent shoulder dislocation are young age, participation in high demand contact sports activities, presence of Hill-Sachs or osseous Bankart lesion, previous history of ipsilateral traumatic dislocation, ipsilateral rotator cuff or deltoid muscle insufficiency, and underlying ligamentous laxity. Achieving the best result for any particular patient depends on the procedure that allows observation of the joint surfaces, provides the anatomical repair, maintains range of motion, and also can be applied with low rates of complications and recurrence. Although various surgical techniques have been described, a consensus does not exist and thus, orthopedic surgeons should follow and try to improve the current evidence-based treatment modalities for the patients.
PubMed: 25405191
DOI: 10.12998/wjcc.v2.i11.676 -
PloS One 2017The biceps or the posterior deltoid can be transferred to improve elbow extension function for many individuals with C5 or C6 quadriplegia. Maximum strength after elbow...
The biceps or the posterior deltoid can be transferred to improve elbow extension function for many individuals with C5 or C6 quadriplegia. Maximum strength after elbow reconstruction is variable; the patient's ability to voluntarily activate the transferred muscle to extend the elbow may contribute to the variability. We compared voluntary activation during maximum isometric elbow extension following biceps transfer (n = 5) and deltoid transfer (n = 6) in three functional postures. Voluntary activation was computed as the elbow extension moment generated during maximum voluntary effort divided by the moment generated with full activation, which was estimated via electrical stimulation. Voluntary activation was on average 96% after biceps transfer and not affected by posture. Individuals with deltoid transfer demonstrated deficits in voluntary activation, which differed by posture (80% in horizontal plane, 69% in overhead reach, and 70% in weight-relief), suggesting inadequate motor re-education after deltoid transfer. Overall, individuals with a biceps transfer better activated their transferred muscle than those with a deltoid transfer. This difference in neural control augmented the greater force-generating capacity of the biceps leading to increased elbow extension strength after biceps transfer (average 9.37 N-m across postures) relative to deltoid transfer (average 2.76 N-m across postures) in our study cohort.
Topics: Adolescent; Adult; Arm; Deltoid Muscle; Elbow Joint; Female; Humans; Male; Middle Aged; Quadriplegia; Range of Motion, Articular; Tendon Transfer; Treatment Outcome; Young Adult
PubMed: 28253262
DOI: 10.1371/journal.pone.0171141 -
The British Journal of Radiology Jul 2014When pain or disability occurs after rotator cuff surgery, post-operative imaging is frequently performed. Post-operative complications and expected post-operative... (Review)
Review
When pain or disability occurs after rotator cuff surgery, post-operative imaging is frequently performed. Post-operative complications and expected post-operative imaging findings in the shoulder are presented, with a focus on MRI, MR arthrography (MRA) and CT arthrography. MR and CT techniques are available to reduce image degradation secondary to surgical distortions of native anatomy and implant-related artefacts and to define complications after rotator cuff surgery. A useful approach to image the shoulder after surgery is the standard radiography, followed by MRI/MRA for patients with low "metal presence" and CT for patients who have a higher metal presence. However, for the assessment of patients who have undergone surgery for rotator cuff injuries, imaging findings should always be correlated with the clinical presentation because post-operative imaging abnormalities do not necessarily correlate with symptoms.
Topics: Arthrography; Artifacts; Deltoid Muscle; Humans; Joint Prosthesis; Magnetic Resonance Imaging; Male; Postoperative Complications; Rotator Cuff; Rotator Cuff Injuries; Rupture; Shoulder Impingement Syndrome; Shoulder Joint; Tomography, X-Ray Computed; Treatment Failure
PubMed: 24734935
DOI: 10.1259/bjr.20130630 -
Medical Ultrasonography May 2022The current difficulty of reverse shoulder arthroplasty (RSA) is soft tissue management, and adequate deltoid tension and at present there is no consensus and available...
AIMS
The current difficulty of reverse shoulder arthroplasty (RSA) is soft tissue management, and adequate deltoid tension and at present there is no consensus and available tools (X-ray, MRI, EMG) remain difficult to apply in clinical follow-up. The objective of this study was (1) to determine reliability and feasibility of deltoid elasticity assessment using ultrasound elastographyand (2) to assess the change of deltoid stiffness after RSA by comparing shear wave speed (SWS) between healthy and RSA shoulders.
MATERIAL AND METHODS
Twenty-six healthy (native shoulder, painless and complete range of motion) subjects and twelve patients with RSA were included. Two independent investigators performed 3 measurements on each segment. Measurements were bilateral. Anterior segment was also evaluated at 45° and 60° of passive abduction. Reliability and feasibility have been assessed (ISO5725-standard).
RESULTS
Coefficient of measurements variation was less than 6.1% and 0.13 m/s. In the healthy group, SWS was not significantly different between anterior and middle segments; however, the SWS of the posterior segment was significantly lower than others (p<0.0001). In abduction position, compared to the rest position, SWS of the anterior segment decreased at 45° abduction (p=0.0003) and increased at 60° abduction (p<0.0001). Variability of measurement was higher in the RSA group. No significant difference was found between the SWS measurement of the operated and non-operated side. SWS measurements of the operated side of the anterior and middle segment were significantly higher compared to the healthy group. In abduction position, compared to rest position, no difference in SWS of the anterior segment was found at 45° abduction (p=0.71) and nor at 60° abduction (p=0.75).
CONCLUSION
This study demonstrated feasibility and reliability of shoulder assessment with shear wave elastography. Reference values for asymptomatic patients can already be used in future studies on shoulder pathology and surgery.
Topics: Arthroplasty, Replacement, Shoulder; Deltoid Muscle; Elasticity Imaging Techniques; Humans; Reproducibility of Results; Shoulder Joint
PubMed: 34762727
DOI: 10.11152/mu-3249 -
Journal of Orthopaedics 2022The clinical effects of axillary nerve injury in the deltoid splitting approach are controversial. This study investigated the axillary nerve function with clinical and...
PURPOSE
The clinical effects of axillary nerve injury in the deltoid splitting approach are controversial. This study investigated the axillary nerve function with clinical and electrophysiologically in proximal humeral fracture patients with internal fixation using the deltoid split approach. We also aimed to investigate the effects of this damage on deltoid muscle volume and discuss the effects of volumetric changes and nerve damage on patients' clinical outcomes.
METHODS
study designed prospectively with 25 consecutive patients who received open reduction and internal fixation of proximal humerus fracture through a deltoid splitting approach. We performed clinical, electrophysiological, and radiological examinations during minimum follow-up time of 24 months. Electrophysiological examination comprised electromyoneurography (EMNG). Functional results followed by Constant-Murley and Disabilities of the Arm, Shoulder, and Hand scores. Deltoid volumes were evaluated with magnetic resonance imaging.
RESULTS
Twenty-five patients operated on with open reduction internal fixation were prospectively observed. In the EMNG measurements of the patients on the 45th postoperative day, partial degeneration was observed in the anterior part of the axillary nerve in all cases (100%). In the control EMNG measurements performed at the 12th month, normal values were obtained for 15 (60%) of the patients, while findings of ongoing regeneration were detected for 10 (40%) of the patients and normal values at all patients at the 24th month. The difference between abnormal and normal EMNG groups' on 12th month Constant-Murley scores was not statistically significant in any period. Only anterior muscle thickness was statistically higher in the normal patient group than with abnormal EMNG results.
CONCLUSIONS
In proximal humeral fractures treated with the deltoid split approach, there may be iatrogenic damage of the anterior branch of the axillary nerve. Axillary nerve damage does not affect the patients' clinical scores in the early and mid-terms.
LEVEL OF EVIDENCE
LEVEL III.
PubMed: 35879940
DOI: 10.1016/j.jor.2022.07.005 -
PeerJ 2023This study aimed to observe the effect of different finger rest positions on the muscular activity of the hand, forearm, arm, shoulder, thorax, and neck, as well as on...
OBJECTIVES
This study aimed to observe the effect of different finger rest positions on the muscular activity of the hand, forearm, arm, shoulder, thorax, and neck, as well as on the angular deviation from the neutral position of the neck, trunk, upper arm, and forearm on the working side during pre-clinical procedures.
METHODS
An experimental laboratory study was performed. Response variables were muscle activation of the abductor pollicis, brachioradialis, biceps brachii, deltoid, pectoralis major, and right sternocleidomastoid muscles and angular deviation from the neutral position of the neck, trunk, arm, and forearm during simulated clinical procedures. Independent variable was finger-rest position during cavity preparation (no finger rest, usual rest, and ergonomic rest). Class I cavity preparations (N = 120) were performed on artificial first molars (16, 26, 36, and 46) (N = 120). Muscular activation was assessed by surface electromyography and angular deviations using Software for Postural Assessment (SAPO) version 0.69. One-way analysis of variance and Tukey's or Games-Howell's tests were performed (α = 0.05).
RESULTS
For the sternocleidomastoid muscle, there was no statistically significant difference between the different rest positions. For the deltoid muscle, work with no finger rest resulted in greater muscle activation ( < 0.001) during work on tooth 36. Regarding the pectoralis major and right brachioradialis muscles, we observed that for both teeth 16 and 26, working with ergonomic rest showed less muscle activation. Muscle activation of the right biceps brachii was higher for work with no rest in both the upper and lower arches, differing significantly only from the usual rest in tooth 16 ( < 0.001), usual rest and ergonomic rest in teeth 26 and 46 ( < 0.001), and only ergonomic rest in tooth 36 ( = 0.044). In the right abductor pollicis muscle, work with ergonomic rest resulted in less muscle activation for cavity preparation in teeth 16, 26, and 36, which was significantly different from work with no rest ( = 0.029, < 0.001, and = 0.013, respectively). Regarding angular deviation, it was observed that for tooth 16, there was a greater angular deviation of the arm when performing cavity preparations with no finger rest. For teeth 26 and 46, the ergonomic finger rest provided lower angular deviation from the neutral position of the right arm. For tooth 36, ergonomic rest provided less angular deviation from the neutral neck position.
CONCLUSION
In general, the use of non-active finger rest during simulated cavity preparations, regardless of the type of rest, provided less muscle activation and angular deviation from the neutral position of the body's upper extremity when performing pre-clinical procedures.
PubMed: 37520265
DOI: 10.7717/peerj.15663 -
Therapeutic Advances in... 2019Aripiprazole lauroxil (AL), a long-acting injectable antipsychotic for the treatment of schizophrenia in adults, can be started with either 21 days of daily oral...
Pharmacokinetics and safety of deltoid or gluteal injection of aripiprazole lauroxil NanoCrystal Dispersion used for initiation of the long-acting antipsychotic aripiprazole lauroxil.
BACKGROUND
Aripiprazole lauroxil (AL), a long-acting injectable antipsychotic for the treatment of schizophrenia in adults, can be started with either 21 days of daily oral aripiprazole supplementation or a 1-day initiation regimen consisting of a single injection of a NanoCrystal Dispersion formulation of AL (AL) and a single dose of 30 mg oral aripiprazole. This phase I study assessed the pharmacokinetics and safety of deltoid gluteal AL injections.
METHODS
Patients with schizophrenia or schizoaffective disorder ( = 47) were randomized 1:1 to receive a single intramuscular dose of AL in the deltoid or gluteal muscle. Plasma samples were collected over 85 days to measure AL concentration by injection site. Relative aripiprazole bioavailability for deltoid gluteal injection was assessed based on area under the curve (AUC and AUC) and maximum concentration (C) values. Adverse events were monitored throughout the study.
RESULTS
Plasma aripiprazole concentrations after a single AL injection were comparable between deltoid and gluteal administration. Mean maximum plasma aripiprazole concentrations were 196.1 ng/ml (deltoid) and 175.0 ng/ml (gluteal). Exposure to aripiprazole was similar, with mean AUC values of 6591 day × ng/ml for deltoid and 6437 day × ng/ml for gluteal. Aripiprazole bioavailability was not significantly different between injection sites. AL administration in the deltoid or gluteal muscle was well tolerated, with similar safety profiles at both sites.
CONCLUSION
AL demonstrated similar exposure and safety profiles between the two administration sites, suggesting that AL can be given in either the gluteal or the deltoid muscles as a component of the 1-day initiation regimen for AL.
PubMed: 31308935
DOI: 10.1177/2045125319859964 -
Experimental Physiology Aug 2019What is the central question of this study? The aim of this study was to examine the effects of resistance training on gains in the external mechanical power output...
NEW FINDINGS
What is the central question of this study? The aim of this study was to examine the effects of resistance training on gains in the external mechanical power output developed during climbing and myofibrillar ATPase activity in rats. What is the main finding and its importance? Using rapid flow quench experiments, we show that resistance training increases both the power output and the myofibrillar ATPase activity in the flexor digitorum profundus, biceps and deltoid muscles. Data fitting reveals that these functional ameliorations are explained by an increase in the rate constant of liberation of ATP hydrolysis products and contribute to performance gains.
ABSTRACT
Skeletal muscle shows a remarkable plasticity that permits functional adaptations in response to different stimulations. To date, modifications of the proportions of myosin heavy chain (MHC) isoforms and increases in fibre size are considered to be the main factors providing sarcomeric plasticity in response to exercise training. In this study, we investigated the effects of a resistance training protocol on the myofibrillar ATPase (m-ATPase) cycle, muscle performance (power output) and MHC gene expression. For this purpose, 8-week-old Wistar Han rats were subjected to 4 weeks of resistance training, with five sessions per week. Muscle samples of flexor digitorum profundus (FDP), biceps and deltoid were collected and subjected to RT-qPCR analyses and assessment of m-ATPase activity with rapid flow quench apparatus. Training led to a significant increase in muscle mass, except for the biceps, and in total mechanical power output (+135.7%, P < 0.001). A shift towards an intermediate fibre type (i.e. MHC2x-to-MHC2a isoform transition) was also observed in biceps and FDP but not in the deltoid muscle. Importantly, rapid flow quench experiments revealed an enhancement of the m-ATPase activity during contraction at maximal velocity (k ) in the three muscles, with a more marked effect in FDP (+242%, P < 0.001). Data fitting revealed that the rate constant of liberation of ATP hydrolysis products (k ) appears to be the main factor influencing the increase in m-ATPase activity. In conclusion, the data showed that, in addition to classically observed changes in MHC isoform content and fibre hypertrophy, m-ATPase activity is enhanced during resistance training and might contribute significantly to performance gains.
Topics: Acclimatization; Adaptation, Physiological; Adenosine Triphosphatases; Animals; Hypertrophy; Muscle Contraction; Muscle Fibers, Skeletal; Muscle, Skeletal; Myosin Heavy Chains; Physical Conditioning, Animal; Rats; Rats, Wistar; Resistance Training; Sarcomeres
PubMed: 31168842
DOI: 10.1113/EP087071 -
Effective stretching position for the posterior deltoid muscle evaluated by shear wave elastography.Journal of Shoulder and Elbow Surgery Aug 2022Deteriorated extensibility of the posterior deltoid muscle is one of the factors of posterior shoulder tightness, and improvement in its extensibility is needed....
BACKGROUND
Deteriorated extensibility of the posterior deltoid muscle is one of the factors of posterior shoulder tightness, and improvement in its extensibility is needed. However, no study has investigated which shoulder positions effectively stretch the posterior deltoid muscle in vivo. The aim of this study was to verify the effective stretching position of the posterior deltoid muscle in vivo by shear wave elastography.
METHODS
Fifteen healthy men participated in this study. The shear modulus of the posterior deltoid was measured at resting and 13 stretching positions: 60°, 90°, and 120° shoulder flexion; maximum shoulder flexion, horizontal adductions at 60°, 90°, and 120° shoulder flexion; internal rotations at 60°, 90°, and 120° shoulder flexion; and combinations of horizontal adduction with internal rotation at 60°, 90°, and 120° shoulder flexion. The shear moduli of each stretching position were compared to those of the rest. Then, among the stretching positions for which the shear modulus was significantly different from the rest, the shear moduli were compared using a three-way analysis of variance with repeated measures of the 3 factors-flexion, horizontal adduction, and internal rotation.
RESULTS
The shear moduli in all stretching positions were significantly higher than those of the rest, except for maximum shoulder flexion. The three-way analysis of variance with repeated measures revealed significant main effects in flexion and horizontal adduction. Comparing the flexion angles, the shear modulus was significantly higher at 90° than that at 60° and 120°. The shear modulus with horizontal adduction was significantly higher than that without horizontal adduction. Moreover, a significant two-way interaction was found only at flexion and horizontal adduction. The shear modulus with horizontal adduction was significantly higher at all angles than that without horizontal adduction at each flexion angle. Comparing the flexion angles with horizontal adduction, the shear modulus was significantly higher at 90° than that at 60° and 120°. No significant three-way interactions were found.
CONCLUSION
Shoulder flexion and horizontal adduction affected the extensibility of the posterior deltoid muscle, whereas the effect of shoulder internal rotation was limited. More precisely, maximal horizontal adduction at 90° shoulder flexion was the most effective stretching position for the posterior deltoid muscle.
Topics: Deltoid Muscle; Elastic Modulus; Elasticity Imaging Techniques; Humans; Male; Muscle Stretching Exercises; Range of Motion, Articular; Shoulder
PubMed: 35245666
DOI: 10.1016/j.jse.2022.01.143