The Acute Effect of Accentuated Eccentric Overloading upon the Kinematics and Myoelectric Activity in the Eccentric and Concentric Phase of a Traditional Bench Press

The target of this study was to investigate the acute effect of a supramaximal augmented eccentric load on the kinematics and myoelectric activity during the concentric phase of the lift in a traditional bench press. Ten resistance-trained males (age 24 ± 6.4 years, height 1.80 ± 0.07 m, body-mass 87.2 ± 16.9 kg) performed two repetitions at 110/85% of the 1-RM in the dynamic accentuated external resistance (DAER) group and two repetitions at 85/85% of the 1-RM for the control group in a traditional bench press. The barbell kinematics, joint kinematics and myoelectric activity of eight muscles were measured in the eccentric phase and the pre-sticking, sticking and post-sticking regions. The main findings were that the sticking region started at a lower barbell height and that a lower barbell velocity was observed in the sticking region during the second repetition in the DAER condition compared to the control condition. Additionally, the lateral deltoid muscle and clavicle part of the pectoralis were more active during the eccentric loading compared to the control condition for the second repetition. Furthermore, higher myoelectric activity was measured during the second repetition in the sticking region for the eccentric loading condition in both pectoralis muscles, while the sternal parts of the pectoralis and anterior deltoid were more active during the second repetition of the control condition in the post-sticking region. Based on our findings, it can be concluded that the supramaximal loading in the descending phase with 110% of the 1-RM in the bench press does not have an acute and positive effect of enhanced performance in the ascending phase of the lift at 85% of 1-RM. Instead, fatigue occurs when using this eccentric load during a bench press.

Axillary Adenopathy Secondary to SARS-CoV-2 Vaccination: a Case Report

Introduction: SARS-CoV-2 mRNA vaccines are safe and effective for the prevention of COVID-19 infection, though local reactions are commonly reported. Axillary lymphadenopathy has also been reported, which has the potential of causing diagnostic confusion and unnecessary testing and procedures. Case Description: A 58 year-old female with untreated latent tuberculosis was noted to have a pulmonary nodule on chest radiograph. Evaluation for Mycobacterium tuberculosis was undertaken, and a FDG PET/CT was performed to rule out malignancy. While the nodule demonstrated low avidity, highly avid lymph nodes were noted in the left axillary region. Further questioning elicited a recent history of mRNA-1273 (Moderna) COVID-19 vaccination in her left deltoid muscle three weeks prior, and a sensation of axillary fullness. She was managed conservatively with spontaneous resolution of her lymphadenopathy. Conclusions: Axillary lymphadenopathy following mRNA vaccination has been reported, and appears to be more common with mRNA-1273 (Moderna) than BNT162b2 vaccine (Pfizer-BioNTech), in those aged 18 to 64 as compared to age ≥65, and following the second vaccine dose compared to the first dose. Vaccination should be considered in the differential diagnosis of axillary lymphadenopathy, particularly ipsilateral to the vaccination site, to avoid unnecessary testing, treatment, and patient anxiety.

«Terrible triad» of the shoulder. Biomechanicalsemi-natural modeling andjustificationto rotator cuff restoration

The aim of this study: was determine the force of tension and deformation of axillary nerve in rupture rotator cuff and paresis of deltoid muscle of the shoulder joint. Material and methods: Semi-natural modelling based on the axial scans spiral computed tomography of the intact shoulder joint was performed to determine the degree of traction load on the axillary nerve with distal displacement shoulder head and tendon rupture which paresis of the deltoid muscle. Result: The values of deformations for axillary nerve being at the limit of tissue strength at distal displacement of humeral head of the model by 50 %, progressively increased with increasing distal displacement of humeral head to 100 % of its diameter, reaching values 1.7 times higher than the strength nervous tissue. Conclusion: The progressive changes occurring in the axillary nerve under the action of traction loads, and as a consequence of its ischemia, over time can lead not only to demyelination, but also to the defeat of the axons themselves atrophy of its fibers. In turn, deltoid muscle atrophy increases the traction load on the affected axillary nerve, which forms a vicious circle. The only possible option to "break" the vicious circle is restore the stabilizing structures damaged during the injury, among which one of the most important is the tendons of the rotator cuff of the shoulder. Surgical restoration of the integrity rotator cuff of the shoulder reduces the traction load acting on the axillary nerve, which in turn significantly improves the conditions for reinnervation of the deltoid muscle.

Latissimus dorsi tendon transposition combined with shoulder joint proximal capsule plasty with peroneal longus tendon autograft in the treatment of patients with massive rotator cuff ruptures and proximal dislocation of the humerus head (clinical case)

The frequency of rotator cuff injuries in people over 45 years of age is 25.6–50 %, and 40 % of these injuries are massive. Shoulder rotator cuff injury causes disorders in biomechanics of the shoulder joint such as anterior-superior dislocation of the humeral head. Injury of the deltoid muscle combined with a massive rupture of the rotator cuff causes proximal dislocation of the humeral head during any active movement. In the treatment of these cases, surgical methods of treatment are used, such as transposition of the latissimus dorsi muscle, proximal capsule plasty, and reverse shoulder arthroplasty. We present a successful clinical case of treatment of a patient with chronic massive injury of the right shoulder joint rotator cuff tendons in combination with the injury of shoulder joint proximal capsule, dislocation of the right humerus head, and hypotrophy of the anterior portion of the deltoid muscle. We performed transposition of the latissimus dorsi tendon in combination with shoulder joint proximal capsule plasty with an autograft of the peroneal longus tendon. The check-up X-rays show that the dislocation of the right shoulder joint was eliminated. In the early postoperative period, the patient started physiotherapy exercises of the operated limb using abduction pillow. By the 7th day after surgery, the abduction of the operated limb reached 70°. The described surgical technique allows to restore congruence in the shoulder joint and the function of the injured limb in severe multiple injuries of the shoulder joint structures.

Focal Myositis of the Deltoid Muscle: The Role of Magnetic Resonance Imaging for Diagnosis

Introduction:Focal myositis is a rare condition first described by Heffner et al., in 1977, as a self-limiting condition of unknown aetiology. It presents as an inflammatory pseudo tumour in skeletal muscle and can present diagnostic difficulty, being commonly mistaken for tissue of vascular, inflammatory, or neoplastic origin. Diagnosis is traditionally confirmed by muscle biopsy. We present a case where magnetic resonance imaging (MRI) was used to confirm the diagnosis without need for biopsy. Case Presentation: A 19-year year-old female presented with a two2-year history of intermittent swelling of the deltoid associated with pain and tenderness to palpation. . There was no history of trauma or systemic illness. . She was symptomatic with pain, swelling, and tenderness over the left deltoid with no restriction in range of movement of the shoulder or neck. Plain radiographs were normal and MRI magnetic resonance imaging showed diffuse odeamatousedematous signal changes on the proton density weighted sequence within the deltoid muscle and no plexiform neurofibroma. Nerve conduction and electromyography studies were within normal limits excluding an axillary nerve lesion. The patient underwent extensive screening for connective tissue disorders and creatine kinase and lactate dehydrogenase levels were within limits. The patient underwent neuromuscular specialist review confirming that this appeared to be a rare case of focal myositis in the deltoid. . The serial MRI scans confirmed resolution of the condition. Conclusion: Focal myositis of the deltoid is a rare cause of shoulder pain. . We have shown that sequential MRI scanning can obviate the need for muscle biopsy, which has historically been required for diagnostic confirmation. The MRI appearance on the proton density weighted sequence showed diffuse odeamatousedematous signal changes and no plexiform neurofibroma within the deltoid and is a description that has not been previously used for this rare diagnosi

Robotic Shoulder Rehabilitation With the Hybrid Assistive Limb in a Patient With Delayed Recovery After Postoperative C5 Palsy: A Case Report

C5 palsy is a serious complication that may occur after cervical spine surgery; however, standard procedures for shoulder rehabilitation for patients with postoperative C5 palsy have not yet been established. We used a wearable robot suit Hybrid Assistive Limb (HAL) in a patient with delayed recovery after postoperative C5 palsy and conducted shoulder abduction training with the HAL. A 62-year-old man presented with weakness in his left deltoid muscle 2 days after cervical spine surgery. He experienced great difficulty in elevating his left arm and was diagnosed with postoperative C5 palsy. Seven months after surgery, shoulder abduction training with a HAL was initiated. In total, 23 sessions of shoulder HAL rehabilitation were conducted until 26 months after surgery. His shoulder abduction angle and power improved at every HAL session, and he was able to fully elevate his arm without any compensatory movement after the 23rd session, suggesting that the HAL is a useful tool for shoulder rehabilitation in patients with postoperative C5 palsy. We employed shoulder HAL training for a patient with delayed recovery from postoperative C5 palsy and achieved complete restoration of shoulder function. We believe that the HAL-based training corrected the erroneous motion pattern of his paralyzed shoulder and promoted errorless motor learning for recovery. Our collective experience suggests that shoulder HAL training could be an effective therapeutic tool for patients with postoperative C5 palsy.