Head Of Muscle Research Articles

Ultrasound acting as a guiding light in the diagnosis of posterior interosseous nerve entrapment at ligament of Frohse – A case report

Posterior interosseous nerve (PIN) entrapment syndrome is a relatively rare compression neuropathy which leads to weakness of the extensor muscles of hand. This becomes a cause of morbidity to the patient with resultant difficulty in conducting day-to-day activities. Thickening of proximal edge of the superficial head of the supinator muscle which forms the ligament of Frohse can lead to compression of the PIN as it enters the supinator canal. Although nerve conduction studies can indicate the diagnosis, they cannot identify the exact site and cause of compression which is crucial for deciding the further management. Magnetic resonance imaging can identify the cause of entrapment in some cases; however, this is extremely difficult given the small size of the PIN and arcade of Frohse. Ultrasound overcomes these limitations and provides a cost and time effective, efficient, and sensitive diagnostic tool for detecting nerve entrapment. Here, we would like to emphasize the emerging importance of ultrasound by describing a case of ligament of Frohse thickening causing PIN entrapment which was effectively diagnosed by ultrasound and confirmed on surgical exploration, treated with surgical ligament release with a full recovery.

Total Elbow Replacement in Swine: Surgical Technique and Initial Clinical Experience in a Kunekune Sow.

The aim of this study was to describe the development of a total elbow replacement (TER) technique in swine and report the outcome of TER in a Kunekune sow (61 kg) with severe elbow osteoarthritis. The technique was developed by operating on three pig cadavers (Yorkshire 40-50 kg). The TATE Elbow implant fit was confirmed with modeling to the patient's computed tomography imaging. Patient-specific instrumentation was printed for attempted use. Total elbow replacement was performed using a lateral approach, including lateral epicondylar osteotomy, careful retraction of the radial nerve, and preservation of the lateral collateral ligament. Postoperative care included controlled exercise and physical therapy. A lateral approach to the pig elbow for TATE TER was successfully developed. The bulk of the lateral head of the triceps muscle precluded use of the patient-specific instrumentation; the procedure was performed using standard instrumentation. Radiographic evidence up to 9 months postoperatively showed adequate implant alignment and satisfactory osteointegration of humeral and radioulnar components. There were not any postoperative complications and the patient's comfort was improved by 6 months and sustained at 18 months. A lateral approach for TATE TER in a pig with advanced elbow osteoarthritis proved feasible and effective. With the expansion of the TATE Elbow line, it is possible that a larger range of pigs could be treated. This report suggests that a lateral approach for TATE TER in dogs could represent a suitable alternative to the medial approach currently used.

Abstract 4134945: Biomechanical Impact of Crossing Neochords In Mitral Valve Repair Using Ex Vivo Mitral Valve Prolapse Models

Background: Neochord repair is a common technique to mitigate mitral regurgitation (MR). Certain techniques, such as the loop technique, purposefully anchor all neochords to one papillary muscle head, generating crossed configurations. The objective was to evaluate the impact of crossing neochord on mitral valve (MV) biomechanics using ex vivo mitral valve prolapse (MVP) models. Methods: Twenty-four healthy porcine MVs were explanted. The valves were randomly assigned to generate A2 or P2 MVP models by transecting A2 or P2 primary and secondary native chords. For each model, the valves were further randomly assigned to neochord repair by crossing the medial-lateral plane or the anterior-posterior plane. Fiber Bragg grating force sensors were mounted to measure chordal forces. Data were collected using an ex vivo heart simulator for baseline, MVP, and neochord repair in the native and the crossed configuration. Statistical analysis was performed using repeated measures analysis of variance with post-hoc correction. Results: In the P2 MVP model, AP crossed configuration was effective in reducing MR (p=.003) compared with the native configuration (p=.004), but the medial-laterally (ML) crossed configuration was not effective in reducing MR (p=.07) compared with the native configuration (p=.05). In the A2 MVP model, anterior-posteriorly crossed configuration was associated with increased average neochordal force compared with the native configuration (0.16±0.06N vs. 0.09±0.07N, p=.05). The ML crossed configuration was also associated with increased average neochordal force compared with the native configuration (0.05±0.03N vs.0.03±0.03N, p=.03). Peak native secondary chordal forces were increased in the ML crossed configuration compared with the native configuration (0.76±0.45N vs. 0.61±0.38N, p=.05). No differences between the crossed and native configurations were observed in the P2 MVP model. Conclusions: Differences exist in P2 MVP model hemodynamics and A2 MVP model chordal forces when neochords were crossed compared with the native configurations. These findings may provide important biomechanics insight regarding neochord implantation techniques and repair durability.

Finite element modeling of concentrated impact loads on the masticatory muscles at the head

AbstractNumerical simulation has great potential to provide a more comprehensive understanding of human impact response to injury mechanisms. Finite Element (FE) models are used as a tool to study human injuries in greater detail, for example, the THUMS (Total Human Model Safety of TOYOTA) model, which is widely used as a reliable human model in different fields to predict human injuries such as fractures, internal organ damage, and brain tissue injuries. However, no available FE model can be used to simulate human‐robot collisions based on standards ISO/TS 15066 and the biomechanical characteristics of human soft tissues in vivo. The authors have developed a head model based on the structures (dimensions and anatomy) of the THUMS head model, specifically designed to simulate impact loads on the masticatory muscles. Based on medical imaging (MRI) data, the soft tissues at the location of the masticatory muscles in the THUMS head are transformed from monolayer to multilayer, that is, a composite geometry of skin‐fat‐muscle each with its own material model and parameters. The model was optimized and validated using the experimental data from the Fraunhofer IFF subjects study, which determined biomechanical thresholds for specific body locations in ISO/TS 15066 under dynamic collisions.

The Sternocleidomastoid Muscle Reverse Pad: A “Safety Net” in Catastrophic Tracheal Surgery Situation

Background: This paper presents the outcomes of employing the inferiorly based rotated sternocleidomastoid muscle flap in complex tracheal reconstruction/repair scenarios, focusing on the key objectives of ensuring stable airway, functional digestive tract and patient survival. Methods: A retrospective analysis was performed for patients treated at two medical centers (A.O. San Camillo Forlanini, Rome, and A.O.U. Careggi, Florence) from 2011 to 2023, in which the sternocleidomastoid muscle (SCM) flap, detached from the mastoid and basicranium, was rotated on the lower pivot directly onto the repair site and pedicled to the sternal origin to ensure the continuity of the airway. Average postoperative hospital stay, follow-up period and patient survival were analyzed. Follow-up assessments encompassed bronchoscopies and CT scans conducted at intervals of 15 and 28 days, and subsequently at 3 and 9 months. Results: A total of five patients were enrolled in this study. These cases included one patient with anterior tracheal wall lesions with abundant tissue loss, one patient with an anterior wall necrosis due to descending cervical mediastinitis and three patients with extra-long tracheoesophageal fistulas (TEFs) (greater than 4.5 cm or >30% of the total tracheal length). In the case of the direct repair of a TEF with a proximal tracheal stenosis, the sternocleidomastoid muscle was used to reconstruct the tissue deficit caused by extensive loss of substance in the left lateral side of the tracheal wall. In case of repair through exclusion of the TEF, the sternocleidomastoid muscle was interposed between the visceral sutures after exclusion of the TEF by an endomechanical device, in one case even substituting the membranous part of the tracheal wall. Our technique allows rotation on the sternal head of the sternocleidomastoid muscle with the lowest rotation radius, pedicled to the sternal origin, detached from the mastoid process and superior nuchal line, thus providing optimal vascularization from the superior thyroid artery/external carotid artery and accessory vasculature from the suprascapular artery. Patients exhibited uneventful postoperative recovery concerning airway and digestive patency. The mean postoperative hospitalization duration was 41 days. The follow-up assessments were negative for postoperative complications. Conclusions: The use of sternocleidomastoid muscle flap was proposed to ensure repair and protection of the suture margin or to constitute a portion, as a scaffold, of the wall by leveraging the muscle’s vascularization and thickness. This technique may be considered a leading component in managing complex situations in tracheal surgery.

Comparison Between InterCriteria and Correlation Analyses over sEMG Data from Arm Movements in the Horizontal Plane

InterCriteria analysis (ICrA) and two kinds of correlation analyses, Pearson (PCA) and Spearman (SCA), were applied to surface electromyography (sEMG) signals obtained from human arm movements in the horizontal plane. Ten healthy participants performed ten movements, eight of which were cyclic. Each cyclic movement (CM) consisted of flexion and extension phases with equal duration (10 s, 6 s, 2 s, and 1 s) and two 5 s rest poses between them. The CMs were performed with and without an added load of 0.5 kg on the wrists of the participants. The sEMG signals from six different muscles or separate muscle heads (m. deltoideus pars clavicularis, m. deltoideus pars spinata, m. brachialis, m. anconeus, m. biceps brachii, and m. triceps brachii long head) were recorded and used to compare the results of the ICrA, PCA, and SCA. All three methods found identical consonance pairs for the flexion and extension CM phases. Additionally, PCA detected two more consonance pairs in the extension phases. In this investigation, ICrA, PCA, and SCA were proven to be reliable tools when applied separately or in combination for sEMG data. These three methods are appropriate for researching arm movements in the horizontal plane and experimental protocol revision.

Beyond Pain: Innovative Approaches to Tension-Type Headache Management and Treatment

Introduction: Tension-type headache (TTH) is a common neurological disorder characterized by bilateral head pain and muscle tension, affecting up to 78% of the population. Despite its prevalence, TTH has historically received less attention than migraines. However, recent years have seen increased interest in understanding its pathophysiology and treatment options. This review comprehensively analyzes TTH management, covering non-pharmacological and pharmacological approaches to guide clinical practice and future research effectively. State of Knowledge: TTHs manifest as bilateral, pressing, encircling head pain, profoundly affecting individuals' quality of life. Recent years have witnessed increased interest in TTH understanding and treatment. Non-pharmacological interventions, including behavioral modifications, exercise, dietary adjustments, sleep hygiene, physical therapy, psychotherapy, and pharmacological treatments like over-the-counter medications, prophylactic drugs, psychedelics, and botulinum toxin A, have shown promise in alleviating symptoms. Conclusion: This review highlights the multifaceted management of TTH. Non-pharmacological interventions, including behavioral modifications and psychotherapy, offer symptom relief. Body awareness therapy, exercise, and psychotherapy benefit TTH symptoms and quality of life. Paracetamol, ibuprofen, and amitriptyline are standard treatments, with emerging options like psychedelics and botulinum toxin A. Personalizing treatment and understanding TTH mechanisms pose challenges. A multidisciplinary approach is essential for enhancing management and outcomes. More research is required to identify optimal treatments and long-term efficacy. Despite challenges, progress in TTH management brings hope for better patient care.

Changes in hamstrings’ active stiffness during fatigue tasks are modulated by contraction duration rather than intensity

Despite the increase in research of hamstring stiffness through the use of ultrasound-based shear wave elastography, the active stiffness of biceps femoris long head (BFlh) and semitendinosus (ST) muscles under fatigue conditions at various contraction intensities has not been sufficiently explored. This study aimed to compare the effects of knee flexor’s isometric contraction until exhaustion performed at 20% vs. 40% of maximal voluntary isometric contraction (MVIC), on the active stiffness responses of BFlh and ST. Eighteen recreationally active males performed two experimental sessions. The knee flexors’ MVIC was assessed before the fatiguing task, which involved a submaximal isometric contraction until failure at 20% or 40% of MVIC. Active muscle stiffness of the BFlh and ST was assessed using shear wave elastography. BFlh active stiffness remained relatively unaltered at 20% of MVIC, while ST active stiffness decreased from ≅ 91% contraction time (55.79 to 44.52 kPa; p < 0.001). No intramuscular stiffness changes were noted in BFlh (36.02 to 41.36 kPa; p > 0.05) or ST (63.62 to 53.54 kPa; p > 0.05) at 40% of MVIC session. Intermuscular active stiffness at 20% of MVIC differed until 64% contraction time (p < 0.05) whereas, at 40% of MVIC, differences were observed until 33% contraction time (p < 0.05). BFlh/ST ratios were not different between intensities (20%=0.75 ± 0.24 ratio vs. 40%=0.72 ± 0.32 ratio; p > 0.05), but a steeper increase in BFlh/ST ratio was found for 20% (0.004 ± 0.003 ratio/%) compared to 40% (0.001 ± 0.003 ratio/%) of MVIC (p = 0.003). These results suggest that contraction duration could play a major role in inducing changes in hamstrings’ mechanical properties during fatigue tasks compared to contraction intensity.

A rare anomalous muscle in the popliteal region - a case report.

Anomalous muscles are rarely seen in the popliteal region of the lower limb. Some of them are harmless and go unnoticed and some create problems such as neuropathies. We report a novel case of an unusual additional muscle in this region. The additional muscle was closely associated with the short head of the biceps femoris muscle. It took its origin from the lower part of the lateral supracondylar line and the adjoining popliteal surface of the femur. The muscle was 10cm in length, 1cm in breadth and was fleshy throughout. It was oriented parallel to the medial side of the tendon of biceps femoris. It was inserted to the posterior aspect of the head of the fibula, medial to the insertion of the biceps femoris. The additional muscle derived its nerve supply from the sciatic nerve. The common peroneal nerve was closely related to the medial border of the additional muscle.

Effectiveness of Massage on Tension Type Headache Pain In Ages 25-50 Years

This research was conducted to determine the effectiveness of massage therapy on reducing tension headache pain in individuals aged 25-50 years. Tension headaches are a common condition characterized by dull, aching head pain and muscle tension in the head and neck. Manual therapy, particularly massage, is a non-invasive treatment that is relatively easy to apply and carries minimal side effects, making it an attractive option for pain relief. The aim of this study is to evaluate the extent to which massage therapy can alleviate tension headache pain in this specific age group. The research design employed a literature review method using the PICO framework and involved databases such as Google Scholar and PubMed. A total of 10 journals met the inclusion criteria and were analyzed. The results showed that massage therapy, when applied twice a week for four weeks with a duration of 45 minutes per session and using gentle pressure, had a statistically significant effect on reducing tension headache pain (p &lt; 0.05). Based on these findings, it can be concluded that manual therapy massage is effective in reducing the severity of pain in individuals suffering from tension headaches, offering a viable treatment option for those seeking non-pharmacological pain management methods.

Prevalence and Interrelationships of Screen Time, Visual Disorders, and Neck Pain Among University Students: A Cross-Sectional Study at Majmaah University.

Digital devices significantly contribute to vision-related problems. In addition, prolonged postural imbalance, owing to excessive use of digital devices, can lead to the tightening of head and neck muscles, resulting in neck pain, a common musculoskeletal discomfort that significantly affects individuals with poor vision. This study aimed to evaluate the prevalence and interrelationships of screen time, visual disorders, and neck pain among students at Majmaah University. A cross-sectional study was conducted at Majmaah University, Saudi Arabia, enrolling students aged 18 to 25 years. Exclusion criteria included neurological or musculoskeletal disorders. Demographic data and information on visual and neck pain symptoms were collected. The Neck Disability Index questionnaire was used to assess neck pain, and data were analyzed using SPSS version 24.0. Among 263 participants, 53.6% were female. Nearsightedness (38.0%) and dry/itchy eyes (49.0%) were the most common visual disorders and symptoms, respectively. Visual disorders were prevalent in 62.0% of students, while neck pain was reported by 79.5%. Females and those studying for more than 5 h using electronic screens daily reported higher neck disability index scores. A significant association was found between >5 h of study duration [screen time] and neck disability (OR 3.703, 95% CI 1.500-9.144, p = 0.005). The study highlights a relationship between visual problems and neck pain among university students, emphasizing the need for addressing vision-related issues to reduce neck discomfort. High screen time could substantially increase the odds of developing neck disability. However, authors warrant cautious interpretation in the light of following limitations: cross-sectional study, small sample size, lack of statistical power, and self-reported data.

Deep peroneal neuropathy induced by prolonged squatting: a case report.

Prolonged squatting is a well-documented cause of common peroneal neuropathy, wherein the common peroneal nerve is thought to be compressed between the biceps femoris tendon and the lateral head of the gastrocnemius muscle or the fibular head. However, deep peroneal neuropathy resulting from prolonged squatting has not been previously reported. We present the case of a tile installer who developed unilateral deep peroneal neuropathy following extended squatting, diagnosed through ultrasonography, which identified the bilateral division of the common peroneal nerves between the knee joint and the fibular head. This case underscores the value of ultrasonography, particularly when electrodiagnostic results are inconsistent with clinical expectations.

Ultrasonographic assessment of the lateral pterygoid muscle for BoNT-A injection.

The upper head of the lateral pterygoid muscle (LPM) is known to insert into the capsule of the temporomandibular joint and articular disc, and therefore its relationship with temporomandibular disorders (TMD) has been consistently suggested. The aim of the study was to determine the anatomical features of the LPM using ultrasonographic (US) imaging. Around 120 hemifaces from 60 healthy Korean volunteers were included in this study. US images were taken with the subject's mouth 2 cm open. The transducer was placed at a position where the infratemporal fossa could be observed through the mandibular notch, and its position was recorded. The locations of the coronoid process (CorP), lateral margin of the condylar process (ConP), and midpoint of CorP and ConP (MP) were measured with reference to the ala-tragus line. The thicknesses of the skin and subcutaneous tissue, the masseter muscle, the temporalis muscle, and the depth of the LPM were measured at the MP. The masseter muscle, temporalis muscle, and LPM were observed in all cases and located in order from superficial to deep. The MP was located 39.6 ± 3.3 mm anterior and 7.8 ± 1.6 mm inferior to the tragus. The thicknesses of the skin and subcutaneous tissue, the masseter muscle, the temporalis muscle, and the depth of the LPM at the MP were 9.7 ± 1.0, 10.3 ± 1.3, 10.9 ± 1.6, and 30.9 ± 1.9 mm, respectively. The information reported in this study may be useful for determining the location of the LPM and adjacent anatomical structures in TMD patients and provide accurate and safe injection guidelines.

Complete foot drop due to atypical peroneal ganglion in a 13 ½ year old boy

IntroductionPeroneal nerve palsy due to compression by an intraneural ganglion is an uncommon entity in the pediatric setting with a need for surgical treatment. Uniquely in this case, the ganglion presented as an elongated instead of a typical round cyst, delaying diagnosis and treatment. Case presentationWe present the case of a 13 ½ year old boy with increasing peroneal nerve palsy due to an atypically shaped intraneural ganglion. An MRI of the knee revealed an elongated peroneal ganglion compressing the nerve between the lateral insertion of the gastrocnemius muscle and fibular head over a length of 10 cm. After surgical decompression and physiotherapy the peroneal nerve recovered well, achieving M 4 – 5 one year after surgery. ConclusionThe atypical shape of the present peroneal ganglion delayed diagnosis and correct treatment. Though rare in the pediatric setting, this entity must be specifically looked for during the diagnostic workup of peroneal palsy, for time to surgery determines neurological outcome.

Estimation of the Achilles tendon twist invivo by individual triceps surae muscle stimulation.

The Achilles tendon (AT) is composed of three distinct subtendons, each arising from one of the three heads of the triceps surae muscles: gastrocnemius medialis (GM), gastrocnemius lateralis (GL), and soleus (SOL). These subtendons exhibit a twisted structure, classified as low (Type I), medium (Type II), and high (Type III) twist, based on cadaveric studies. Nevertheless, the invivo investigation of AT twist is notably scarce, resulting in a limited understanding of its functional significance. The aim of this study was to give insights into the complex 3D AT structure invivo. A total of 30 healthy participants underwent individual stimulation of each of the triceps surae muscles at rest with the foot attached to the pedal of an isokinetic dynamometer. Ultrasound images were captured to concomitantly examine the displacement of the superficial, middle and deep AT layers. SOL stimulation resulted in the highest AT displacement followed by GM and GL stimulation. Independent of the muscle stimulated, non-uniformity within the AT was observed with the deep layer exhibiting more displacement compared to the middle and superficial layers, hence important inter-individual differences in AT displacement were noticeable. By comparing these individual displacement patterns during targeted stimulations with insights from cadaveric twist classifications on each subtendon area, our classification identified 19 subjects with a 'low' twist and 11 subjects with a 'high' twist. These findings enable us to move beyond cadaveric studies and relate the twisted microstructure of the AT invivo to its dynamic behaviour.

Late Presentation of Poland Syndrome: A Case Report of a 45-year-old Male with Unilateral Chest Wall Anomalies

ABSTRACT Poland syndrome (PS) is a rare congenital disorder characterized by unilateral chest wall anomalies, including the absence or underdevelopment of the pectoralis major muscle. Typically diagnosed in childhood because of visible physical deformities, cases presenting in adulthood are rare and present unique diagnostic challenges. We report the case of a 45-year-old male with longstanding but progressively concerning asymmetry of the chest wall. The patient, who had noticed mild differences since childhood, sought medical evaluation due to increased discomfort. Physical examination revealed the absence of the sternal head of the right pectoralis major muscle. Imaging studies, including chest X-ray and computed tomography, confirmed the diagnosis of PS. This case highlights the variability in the presentation of PS and the potential for delayed diagnosis in adulthood. The rarity of late presentations underscores the need for clinicians to consider PS in the differential diagnosis of unilateral chest wall anomalies, even in adult patients. Management strategies are discussed, emphasizing the importance of a multidisciplinary approach, including surgical intervention and physiotherapy tailored to the patient’s specific functional and esthetic needs. PS can present later in life, and increased awareness among health-care providers is essential for timely diagnosis and management. Addressing functional and cosmetic concerns through a personalized treatment plan can significantly enhance patient outcomes and quality of life.

Quantifying toddler exploration in different postures with powered mobility

ABSTRACT Access to powered mobility can support play and development for toddlers with disabilities. Using powered mobility in a standing posture has been theorized to support development of muscle coordination, balance, head and trunk stability, and transition to ambulation. The purpose of this study was to quantify and characterize joystick control, bodyweight support, and muscle activity while using the Permobil Explorer Mini in seated and supported standing postures. Nine children with mobility disabilities participated in four visits where they completed two, 15–20 minute play sessions, one in each posture, with a break between. We found that all toddlers engaged with the joystick in both postures, with individual differences in favored directions and control patterns. Participants had similar loading through their feet in both postures, but had slightly higher muscle activity in standing, especially while driving. These results demonstrate that young children with disabilities quickly engage with joystick-based powered mobility in seated and standing postures, with important individual differences that can inform future design of devices and interventions to support play and development.

Light weights are as effective as heavy weights for muscle activation in the Hammerobics exercise.

We previously reported that a Hammerobics exercise using weights can enhance trunk and lower extremity muscles, some studies suggested that training effects could also be expected without heavy weights. If the muscle activity induced by Hammerobics swinging with a 'light plastic ball' equals or surpasses that of the isometric static squat and synchronized squat with a heavy ball, this training approach could alleviate joint strain, fostering an exercise regimen universally accessible across generations, benefit for workouts sports and rehabilitation. Fifteen healthy men participated in this study. By using surface electromyography, muscle activities for the abductor hallucis, tibialis anterior, tibialis posterior, peroneus longus, rectus femoris, biceps femoris long head, semitendinosus, gluteus maximus, multifidus, and internal oblique muscles were measured during a light Hammerobics synchronized squat (HSS-light), Hammerobics synchronized squat, and conventional isometric squat, and statistically compared. The front-to-back tibialis anterior activity of HSS-light was significantly higher than that of conventional isometric squat. The activities of all other muscles, except for the multifidus, were not significantly different between these exercises in the front-to-back and back-to-front phases. Compared to the Hammerobics synchronized squat, the light Hammerobics synchronized squat showed no differences in front-to-back tibialis anterior, rectus femoris, biceps femoris long head, and internal oblique activities and back-to-front abductor hallucis, tibialis anterior, rectus femoris, and internal oblique activities. The HSS-light could stimulate muscles to the same level as the conventional isometric squat without weight bearing. While the HSS-light was less effective than the Hammerobics synchronized squat, there was no significant difference in internal oblique, rectus femoris, and tibialis anterior activities between these exercises. Hence, the HSS-light is an exercise method that can be viable approach to promoting accessible workouts sports and rehabilitation.

Signal quality evaluation of an in-ear EEG device in comparison to a conventional cap system.

Wearable in-ear electroencephalographic (EEG) devices hold significant promise for integrating brain monitoring technologies into real-life applications. However, despite the introduction of various in-ear EEG systems, there remains a necessity for validating these technologies against gold-standard, clinical-grade devices. This study aims to evaluate the signal quality of a newly developed mobile in-ear EEG device compared to a standard scalp EEG system among healthy volunteers during wakefulness and sleep. The study evaluated an in-ear EEG device equipped with dry electrodes in a laboratory setting, recording a single bipolar EEG channel using a cross-ear electrode configuration. Thirty healthy participants were recorded simultaneously using the in-ear EEG device and a conventional EEG cap system with 64 wet electrodes. Based on two recording protocols, one during a resting state condition involving alternating eye opening and closure with a low degree of artifact contamination and another consisting of a daytime nap, several quality measures were used for a quantitative comparison including root mean square (RMS) analysis, artifact quantification, similarities of relative spectral power (RSP), signal-to-noise ratio (SNR) based on alpha peak criteria, and cross-signal correlations of alpha activity during eyes-closed conditions and sleep activities. The statistical significance of our results was assessed through nonparametric permutation tests with False Discovery Rate (FDR) control. During the resting state, in-ear and scalp EEG signals exhibited similar fluctuations, characterized by comparable RMS values. However, intermittent signal alterations were noticed in the in-ear recordings during nap sessions, attributed to movements of the head and facial muscles. Spectral analysis indicated similar patterns between in-ear and scalp EEG, showing prominent peaks in the alpha range (8-12 Hz) during rest and in the low-frequency range during naps (particularly in the theta range of 4-7 Hz). Analysis of alpha wave characteristics during eye closures revealed smaller alpha wave amplitudes and slightly lower signal-to-noise ratio (SNR) values in the in-ear EEG compared to scalp EEG. In around 80% of cases, cross-correlation analysis between in-ear and scalp signals, using a contralateral bipolar montage of 64 scalp electrodes, revealed significant correlations with scalp EEG (p < 0.01), particularly evident in the FT11-FT12 and T7-T8 electrode derivations. Our findings support the feasibility of using in-ear EEG devices with dry-contact electrodes for brain activity monitoring, compared to a standard scalp EEG, notably for wakefulness and sleep uses. Although marginal signal degradation is associated with head and facial muscle contractions, the in-ear device offers promising applications for long-term EEG recordings, particularly in scenarios requiring enhanced comfort and user-friendliness.

Comparison of the Efficacy of 2 Different Botulinum Toxin Injection Techniques in Gastrocnemius Muscle Spasticity in Hemiplegic Patients: A Randomized Double-Blind Controlled Study

ObjectiveTo compare the efficacy of the innervation zone–targeted injection technique (EUROMUSCULUS/USPRM (Ultrasound Study Group of the International Society of Physical and Rehabilitation Medicine) spasticity approach) and the injection technique along the muscle length. DesignA double-blind randomized controlled trial. SettingDepartment of rehabilitation medicine of a medical center. ParticipantsOne hundred patients with stroke experiencing ankle plantar flexor spasticity. InterventionsIn addition to conventional rehabilitation, eligible patients were randomly assigned to 2 groups. The experimental group was injected with botulinum toxin along the length of the muscle, whereas the control group was injected with the same dose and volume of botulinum toxin 25%-35% proximal to the medial head and 20%-30% proximal to the lateral aspect of the head of the gastrocnemius muscle. Main Outcome MeasuresModified Ashworth scale, modified Tardieu scale, ankle range of motion measurement, and 10-meter walk test were used before and 1 month after injection. ResultsThe study was completed by 60 participants with a mean age of 59.96±12.15 years. Both injection methods were found to be effective on range of motion, spasticity level, ambulation, and walking speed. There was no statistically significant difference between injection methods. ConclusionsBoth injection methods of botulinum toxin A produce similar clinical effects.