The Use of the Velocity Selective Recording Technique to Reveal the Excitation Properties of the Ulnar Nerve in Pigs

Decoding information from the peripheral nervous system via implantable neural interfaces remains a significant challenge, considerably limiting the advancement of neuromodulation and neuroprosthetic devices. The velocity selective recording (VSR) technique has been proposed to improve the classification of neural traffic by combining temporal and spatial information through a multi-electrode cuff (MEC). Therefore, this study investigates the feasibility of using the VSR technique to characterise fibre type based on the electrically evoked compound action potentials (eCAP) propagating along the ulnar nerve of pigs in vivo. A range of electrical stimulation parameters (amplitudes of 50 μA–10 mA and pulse durations of 100 μs, 500 μs, 1000 μs, and 5000 μs) was applied on a cutaneous and a motor branch of the ulnar nerve in nine Danish landrace pigs. Recordings were made with a 14 ring MEC and a delay-and-add algorithm was used to convert the eCAPs into the velocity domain. The results revealed two fibre populations propagating along the cutaneous branch of the ulnar nerve, with mean velocities of 55 m/s and 21 m/s, while only one dominant fibre population was found for the motor branch, with a mean velocity of 63 m/s. Because of its simplicity to provide information on the fibre selectivity and direction of propagation of nerve fibres, VSR can be implemented to advance the performance of the bidirectional control of neural prostheses and bioelectronic medicine applications.

Right medium-sized vestibular schwannoma with trigeminal neuralgia post-fractionated radiotherapy

A patient with trigeminal neuralgia secondary to a vestibular schwannoma underwent fractionated radiotherapy without relief of her pain. She was then effectively treated with microsurgical resection of her tumor. Early identification of the lower cranial nerves and the origin of the facial and vestibulocochlear nerves is key to determining the operative corridors for vestibular schwannoma resection. To effectively treat trigeminal neuralgia, the trigeminal nerve root entry zone and motor branch are clearly identified and decompressed. Fractioned radiotherapy does not effectively treat trigeminal neuralgia secondary to vestibular schwannoma compression. The video can be found here: https://stream.cadmore.media/r10.3171/2021.7.FOCVID21112

Triceps and cutaneous radial nerve branches investigated via an axillary anterior arm approach: new findings in a fresh-cadaver anatomical study

OBJECTIVE The authors sought to describe the anatomy of the radial nerve and its branches when exposed through an axillary anterior arm approach. METHODS Bilateral upper limbs of 10 fresh cadavers were dissected after dyed latex was injected into the axillary artery. RESULTS Via the anterior arm approach, all triceps muscle heads could be dissected and individualized. The radial nerve overlaid the latissimus dorsi tendon, bounded by the axillar artery on its superior surface, then passed around the humerus, together with the lower lateral arm and posterior antebrachial cutaneous nerve, between the lateral and medial heads of the triceps. No triceps motor branch accompanied the radial nerve’s trajectory. Over the latissimus dorsi tendon, an antero-inferior bundle, containing all radial nerve branches to the triceps, was consistently observed. In the majority of the dissections, a single branch to the long head and dual innervations for the lateral and medial heads were observed. The triceps long and proximal lateral head branches entered the triceps muscle close to the latissimus dorsi tendon. The second branch to the lateral head stemmed from the triceps lower head motor branch. The triceps medial head was innervated by the upper medial head motor branch, which followed the ulnar nerve to enter the medial head on its anterior surface. The distal branch to the triceps medial head also originated near the distal border of the latissimus dorsi tendon. After a short trajectory, a branch went out that penetrated the medial head on its posterior surface. The triceps lower medial head motor branch ended in the anconeus muscle, after traveling inside the triceps medial head. The lower lateral arm and posterior antebrachial cutaneous nerve followed the radial nerve within the torsion canal. The lower lateral brachial cutaneous nerve innervated the skin over the biceps, while the posterior antebrachial cutaneous nerve innervated the skin over the lateral epicondyle and posterior surface of the forearm. The average numbers of myelinated fibers were 926 in the long and 439 in the upper lateral head and 658 in the upper and 1137 in the lower medial head motor branches. CONCLUSIONS The new understanding of radial nerve anatomy delineated in this study should aid surgeons during reconstructive surgery to treat upper-limb paralysis.

Posterior interosseous neuropathy: distinguishing from a proximal radial neuropathy

The posterior interosseous nerve is the terminal motor branch of the radial nerve that innervates the extensor carpi ulnaris and the extensors of the thumb and fingers. We describe a case of a posterior interosseous neuropathy presenting with the typical ‘finger drop’ and partial ‘wrist drop’. We focus on the clinical signs that distinguish it from a more proximal radial neuropathy, clarified by nerve conduction studies and needle electromyography. Multimodal imaging of the forearm did not identify a compressive lesion. Persistent symptoms prompted surgical exploration 5 years after initial onset. It identified compression of the posterior interosseous nerve in the region of the arcade of Frohse and leash of Henry. The sites were decompressed and concurrent salvage secondary reconstructive tendon transfers were required in view of the severe axonal loss with minimal chance of functional reinnervation.

Topographical, anatomical and neurosurgical aspects of "end-to-side" nerve repair

The article presents the results of a comprehensive anatomical and experimental study of individual variability in the structure and topography of motor branches of peripheral nerves in relation to the justification of methods for selective reinnervation of tissues by the "end-to-side" neurorrhaphy. It was found that relatively longer branches of peripheral nerves with a small number of connecting inter-arm collaterals characteristic of narrow and long limbs create conditions for less traumatic mobilization of motor branches. In cases with relatively wide and short extremities mobilization of peripheral nerves is complicated by the presence of a large number of collateral branches and intra-trunk connections, which are often damaged when separate bundles that make up the mobilized branches of the donor or recipient nerve are isolated from the main nerve trunk. It has been shown that potential recipient nerves should be motor branches of peripheral nerves, the preservation of which is of fundamental importance for the function of the corresponding segment of the limb. To create conditions conducive to selective reinnervation of functionally significant muscle groups of the upper limb, we have developed, justified from anatomical positions, and tested in an experiment on anatomical material methods for connecting the distal motor branches of peripheral nerves by the "end-to-side" neurorrhaphy. The main idea of accelerated recovery of the thumb opposition in injuries of the median nerve is to reinnervate the muscles of the elevation of the I finger due to nerve fibers that are part of the deep branch of the ulnar nerve. For this purpose, surgical techniques have been developed for connecting the recurrent motor branch of the damaged median nerve mobilized at the level of the wrist with the edges of a surgically formed perineurium defect on the lateral surface of the bundles that make up the deep branch of the ulnar nerve. In another clinical situation, in patients with radial nerve injuries, for the muscle reinnervation, а method is proposed for neurotisation of the deep motor branch of the radial nerve by the end-to-side suture to the lateral surface of the median nerve. We assume that performing the "end-to-side" nerve suture at the level of the base of the hand in the cases of proximal damage to the median nerve will reduce the time of reinnervation of the muscles of the thumb elevation by 400450 days. Transposition of the deep branch of the damaged at the proximal level radial nerve with "end-to-side" neurorrhaphy to the median nerve by 250300 days (based on the total length of the shoulder and forearm, which is about 50 cm and the rate of regeneration of nerve fibers 1 mm per day). Accordingly, with higher injuries (brachial plexus), the gain in the time of reinnervation of the distal segments will be even greater. In our opinion, the results can be used as a basis for further clinical research on the development of methods for selective tissue reinnervation in cases with isolated injuries of the peripheral nerves.

Pigmented Villo Nodular Synovitis as an Atypical Cause of Deep Motor Branch Neuropathy

Introduction: Compression of the ulnar nerve in Guyon’s canal results in ulnar tunnel syndrome (UTS). The patient may present with sensory and motor deficits (zone 1), motor deficit (zone 2), or sensory deficit (zone 3). The most common causes of UTS include ganglion cysts, idiopathic ulnar nerve compression, occupational pressure neuritis (repetitive compression), prolonged compression, hook of hamate fractures, and arterial thrombus or aneurysm. Case Report: We report an atypical cause of UTS involving pigmented villonodular synovitis (PVNS) with a review of the literature. Surgical decompression of the ulnar nerve at Guyon’s canal has resulted in resolving motor weakness and improved interosseous strength at latest follow-up. Conclusion: The most common causes of UTS are ganglion, occupational neuritis, prolonged compression, and ulnar artery thrombi/aneurysms. However, other more rare causes such as PVNS should be considered in the appropriate patient. Keywords: Neuropathy, ulnar nerve, ulnar tunnel.

AXILLARY NERVE SUPPLYING MOTOR BRANCH TO LONG HEAD OF TRICEPS BRACHII MUSCLE: A CASE REPORT AND REVIEW OF LITERATURE

All three heads of the triceps brachii are classically described as being innervated by the radial nerve in the textbooks. Some clinical observations of traumatic injuries of the axillary nerve with associated paralysis of the long head of triceps and cadaveric studies have suggested that the axillary nerve may innervate the long head of triceps. During routine dissection to undergraduate M.B.B.S students, we found axillary nerve giving a motor branch to long head of triceps brachii on right side, in an adult male cadaver aged about 60 years. We conducted extensive literature search to analyse the previous studies reporting such variations and the studies conducted on the radial nerve or triceps brachii innervation pattern. This variation is clinically important for surgeons, orthopedicians and anaesthetist while performing surgeries and pain management therapies on the upper limb.

The influence of Service Quality on Customer Satisfaction at Workshop PT Wahana Sun Motor Branch Puri Anjasmoro

<em>This study aimed to determine the influence of service quality on customer satisfaction at workshop PT Wahana Sun Motor Branch Office Puri Anjasmoro. This research used the dimensions of service quality, namely : tangible, reliability, responsiveness, assurance, and empathy to customer satisfaction. Data analysis that used were instrument test, classical assumption test, multiple linear regression analysis, and hypothesis test. The sample that used in this study were 100 respondents that choosen using probability sampling method. Hypothesis test result indicate that tangible, reliability, responsiveness, assurance, and empathy influencing the customer satisfaction. Furthermore, tangible, reliability, responsiveness, assurance, and empathy simultaneously influencing the customer satisfaction. The results of the coefficient of determination indicate that tangible, reliability, responsiveness, assurance, and empathy influencing the customer satisfaction by 60,3% and the remaining 39,7% of customer satisfaction is influenced by other factors which were not observed in this study</em>

The influence of Work Environment, Job Satisfaction, and Organizational Commitment on Employee Performance at PT Sun Star Motor Branch MT Haryono Semarang

<em>Employee performance of </em> <em>PT Sun Star Motor</em> <em>is affected by many factors. This research aims to analiyze the influence of work environment, job satisfaction, and organizational commitment on employee performance at PT Sun Star Motor Branch MT Haryono Semarang</em>. <em>The technique of analysis used is multiple linear regression. The population and sample </em><em>are the entire of employees of PT Sun Star Motor Branch MT Haryono</em> <em>is 40 people. Data collection method used are questionnaire, participant observation and literature review. The results of F-test, shows that work environment, job satisfaction, and organizational commitment has significant affect on employee performance at PT Sun Star Motor Branch MT Haryono Semarang. Based on the results of the t test, the work environment has a significant positive effect on the employee performance of PT Sun Star Motor Branch MT Haryono Semarang. Job satisfaction has no significant effect on employee performance at PT Sun Star Motor Branch MT Haryono Semarang. And organizational commitment has significant positive effect on employee performance at PT Sun Star Motor Branch MT Haryono Semarang. While the coefficient of determination (adjusted R²) of employee performance is 61.8% which is explained by work environment, job satisfaction, and organizational commitment. The remaining 38.2% is influenced by other factors outside the model</em>