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The role of afferent feedback and central motor drive in muscle activation has a profound impact on our understanding of movement control in health and disease. Dr. Richard B. Stein was a pioneer who made major contributions to the field. In addition to fundamental discoveries using animal models, he translated this to the clinic to benefit patients with spinal cord and other neurological injuries. Along the way, he inspired a generation of scientists around the world. Key words: neurophysiology, motor control, translational medicine Le role de la retroaction afferente et de l'activite motrice centrale sur l'activation musculaire a une incidence profonde sur notre comprehension du controle des mouvements chez les personnes en bonne sante comme chez les malades. Le docteur Richard B. Stein a ete un pionnier en ce sens, avec des contributions majeures dans le domaine. Il est parvenu a des decouvertes fondamentales a l'aide de modeles chez les animaux qu'il a su de surcroit appliquer en clinique pour le bienfait des patients atteints de lesions de la moelle epiniere et ailleurs dans le systeme nerveux. Tout au long de son parcours, il a ete une source d'inspiration pour une generation de scientifiques partout dans le monde. Mots-cles : neurophysiologie, controle moteur, medecine translationnelle, Introduction The passing of Richard B. Stein (RBS), a giant in the field of neurophysiology, was a major loss and he will be much missed (Fig. 1). Dick, as he [...]

Simple Summary: Head and neck cancer is associated with significant morbidity. Shoulder and neck dysfunction, weight loss, and declines in muscular strength and physical functioning are commonly seen following cancer therapies. This pragmatic randomized controlled trial involved sixty-one individuals with cancer in the head and neck region who had completed their cancer treatment. The primary aim was to assess the effectiveness of the addition of lower-body resistance exercise training to a physiotherapeutic shoulder and neck exercise protocol on fatigue-related quality of life. Findings support the benefit of the combined intervention for fatigue-related quality of life, six-minute walk test distance, upper- and lower-body muscular strength, and physical activity level. The continued improvement in treatment effect over the one-year follow-up period suggests promise from this interdisciplinary approach to bridge individuals with head and neck cancer from rehabilitation care to general exercise and physical activity. Background: Established barriers to general exercise and physical activity among individuals with head and neck cancer include dry mouth, difficulty eating, weight loss, fear of injury, comorbidities, and treatment-related symptoms of pain and fatigue. Methods/Design: A 12-week pragmatic randomized controlled trial was conducted followed by an optional supported exercise transition phase. Eligible participants were individuals with head and neck cancers who had undergone surgery and/or radiation therapy to lymph node regions in the neck. Participants were randomized to a comparison group involving a shoulder and neck physiotherapeutic exercise protocol, or to a combined experimental group comprising the shoulder and neck physiotherapeutic exercise protocol and lower-body resistance exercise training. The primary outcome of this study was fatigue-related quality of life. Results: Sixty-one participants enrolled, 59 (97%) completed the randomized trial phase, 55 (90%) completed the 24-week follow-up, and 52 (85%) completed the one-year follow-up. Statistically significant between-group differences were found in favor of the combined experimental group for the fatigue-related quality of life, fitness outcomes, and overall physical activity. Paired comparisons confirmed significant within-group improvements for both groups from baseline to one-year follow-up across most outcomes. Discussion: A group-based combined physiotherapeutic and lower-body resistance exercise program was feasible and effective. Findings are limited to individuals who had undergone a surgical neck dissection procedure. Given the complexity of head and neck cancer, further pragmatic interdisciplinary research is warranted. [ABSTRACT FROM AUTHOR]

Introduction/Aims: It is important to quantify the amount of crossover innervation from the anterior interosseous nerve (AIN) through Martin‐Gruber anastomosis (MGA) particularly in patients with high ulnar nerve injury who undergo nerve transfer surgery. The objective of this study is to describe a novel electrophysiological method for quantifying innervation from the AIN that can be done using conventional nerve conduction study setup and commonly available software for analysis. Methods: Seven subjects with MGA and nine patients who had undergone AIN to ulnar nerve transfer underwent conventional motor nerve conduction studies. Recording was done over the hypothenar and first dorsal interosseous muscles while stimulating the median and ulnar nerves at the wrist and elbow. Datapoint‐by‐datapoint subtraction of the compound muscle action potentials evoked at the elbow and wrist was performed after they had been onset‐aligned. The results were compared to the collision technique and innervation ratio method. Result: Results from the digital subtraction method were highly correlated with the collision technique (r = 0.96, p < 0.05). In contrast, its correlation with the innervation ratio method is substantially lower. Discussion: In comparison to previously described techniques, the digital subtraction method has a number of practical advantages. It uses conventional nerve conduction study setup, and the added step of digital alignment and subtraction can be done through commonly available software. With the increasing use of nerve transfer surgery in severe high ulnar nerve injury, this could be a useful method to identify the presence of MGA prior to surgery and for evaluating nerve recovery following surgery. [ABSTRACT FROM AUTHOR]

Neural prostheses are electronic stimulators that activate nerves to restore sensory or motor functions. Implanted neural prostheses receive command signals and in some cases energy to recharge their batteries through the skin by telemetry. Here, we describe a new approach that eliminates the implanted stimulator. Stimulus pulse trains are passed between two surface electrodes placed on the skin. An insulated lead with conductive terminals at each end is implanted inside the body. One terminal is located under the cathodal surface electrode and the other is attached to a nerve targeted for stimulation. A fraction (10%-15%) of the current flowing between the surface electrodes is routed through the implanted lead. The nerve is stimulated when the amount of routed current is sufficient. The aims of this study were to establish some basic electrical properties of the system and test long-term stability in chronic implants. Stimulation of the nerve innervating the ankle flexors produced graded force over the full physiological range at amplitudes below threshold for evoking muscle contractions under the surface electrodes. Implants remained stable for over 8 mo. The findings provide the basis for a new family of neural prostheses. Index Terms--Functional electrical stimulation, neural prostheses, passive implant.

Case: The reconstruction of large nerve gaps remains a reconstructive challenge. Here, we present a case report of brachial plexus reconstruction using nerve grafts harvested as spare parts from an amputated limb. It also allowed us to use motor nerve grafts to reconstruct defects in the posterior cord and musculocutaneous nerve. The patient recovered good shoulder and elbow function at 2.5 years with evidence of innervation distally on electromyography. Conclusion: Spare part surgery should always be kept in a surgeons' reconstructive algorithm. Reconstruction of large nerve gaps can be achieved with autologous nerve grafts in certain circumstances. [ABSTRACT FROM AUTHOR]

Objective: Compared to the upper limb, lower limb distal nerve transfer (DNT) outcomes are poor, likely due to the longer length of regeneration required. DNT surgery to treat foot drop entails rerouting a tibial nerve branch to the denervated common fibular nerve stump to reinnervate the tibialis anterior muscle for ankle dorsiflexion. Conditioning electrical stimulation (CES) prior to nerve repair surgery accelerates nerve regeneration and promotes sensorimotor recovery. We hypothesize that CES prior to DNT will promote nerve regeneration to restore ankle dorsiflexion.Methods: One week following common fibular nerve crush, CES was delivered to the tibial nerve in half the animals, and at 2 weeks, all animals received a DNT. To investigate the effects of CES on nerve regeneration, a series of kinetic, kinematic, skilled locomotion, electrophysiologic, and immunohistochemical outcomes were assessed. The effects of CES on the nerve were investigated.Results: CES-treated animals had significantly accelerated nerve regeneration (p < 0.001), increased walking speed, and improved skilled locomotion. The injured limb had greater vertical peak forces, with improved duty factor, near-complete recovery of braking, propulsive forces, and dorsiflexion (p < 0.01). Reinnervation of the tibialis anterior muscle was confirmed with nerve conduction studies and immunohistochemical analysis of the neuromuscular junction. Immunohistochemistry demonstrated that CES does not induce Wallerian degeneration, nor does it cause macrophage infiltration of the distal tibial nerve.Interpretation: Tibial nerve CES prior to DNT significantly improved functional recovery of the common fibular nerve and its muscle targets without inducing injury to the donor nerve. ANN NEUROL 2020;88:363-374. [ABSTRACT FROM AUTHOR]

Background: Ulnar neuropathy at the elbow (UNE) is the second commonest entrapment neuropathy after carpal tunnel syndrome (CTS) and yet the laterality is not well delineated. Our aim was to establish the laterality of UNE in a large cohort of patients.Methods: All new patients with clinical and electrodiagnostic (EDX) confirmed UNE over a 13-year period were included. We used multivariate analysis to examine potential predictors of laterality, and unilateral vs bilateral UNE.Results: Of 880 cases, 61% were left-sided and 39% right-sided. These proportions did not change regardless of the handedness of the patient. Patients with bilateral UNE were much more likely to be older male and have a variety of comorbidities.Conclusions: UNE appears to be present on the left 50% more often than on the right, regardless of the patient's handedness. [ABSTRACT FROM AUTHOR]

Abstract Peripheral nerve regeneration following injury is often incomplete, resulting in significant personal and socioeconomic costs. Although a conditioning crush lesion prior to surgical nerve transection and repair greatly promotes nerve regeneration and functional recovery, feasibility and ethical considerations have hindered its clinical applicability. In a recent proof of principle study, we demonstrated that conditioning electrical stimulation (CES) had effects on early nerve regeneration, similar to that seen in conditioning crush lesions (CCL). To convincingly determine its clinical utility, establishing the effects of CES on target reinnervation and functional outcomes is of utmost importance. In this study, we found that CES improved nerve regeneration and reinnervation well beyond that of CCL. Specifically, compared to CCL, CES resulted in greater intraepidermal skin and NMJ reinnervation, and greater physiological and functional recovery including mechanosensation, compound muscle action potential on nerve conduction studies, normalization of gait pattern, and motor performance on the horizontal ladder test. These findings have direct clinical relevance as CES could be delivered at the bedside before scheduled nerve surgery. Highlights • Conditioning crush lesions promote sensorimotor nerve regeneration but are not clinically feasible. • Conditioning electrical stimulation promotes nerve regeneration and sensorimotor recovery superior to the conditioning crush. • Electrical stimulation is clinically safe, well-tolerated, and can be performed prior to a scheduled nerve repair surgery. • Conditioning electrical stimulation may significantly improve clinical outcomes for patients with peripheral nerve injuries. [ABSTRACT FROM AUTHOR]

By altering the intrinsic metabolism of the cell, including the upregulation of regeneration-associated genes (RAGs) and the production of structural proteins for axonal outgrowth, the conditioning lesion sets up an environment highly conducive to regeneration. In this review, we assess 40 years of research to provide a comprehensive overview of the conditioning lesion literature, directed at (1) discussing the mechanisms of and barriers to nerve regeneration that can be mitigated by the conditioning lesion, (2) describing the cellular and molecular pathways implicated in the conditioning lesion effect, and (3) deliberating on how these insights might be applied clinically. The consequential impact on regeneration is profound, with a conditioned nerve demonstrating longer neurite extensions in vitro, enhanced expression of RAGs within the dorsal root ganglia, early assembly and transportation of cytoskeletal elements, accelerated axonal growth, and improved functional recovery in vivo. Although this promising technique is not yet feasible to be performed in humans, there are potential strategies, such as conditioning electrical stimulation that may be explored to allow nerve conditioning in a clinically safe and well-tolerated manner. Ann Neurol 2018;83:691-702. [ABSTRACT FROM AUTHOR]

Background: Myoelectric prostheses currently used by amputees can be difficult to control. Machine learning, and in particular learned predictions about user intent, could help to reduce the time and cognitive load required by amputees while operating their prosthetic device.Objectives: The goal of this study was to compare two switching-based methods of controlling a myoelectric arm: non-adaptive (or conventional) control and adaptive control (involving real-time prediction learning).Study Design: Case series study.Methods: We compared non-adaptive and adaptive control in two different experiments. In the first, one amputee and one non-amputee subject controlled a robotic arm to perform a simple task; in the second, three able-bodied subjects controlled a robotic arm to perform a more complex task. For both tasks, we calculated the mean time and total number of switches between robotic arm functions over three trials.Results: Adaptive control significantly decreased the number of switches and total switching time for both tasks compared with the conventional control method.Conclusion: Real-time prediction learning was successfully used to improve the control interface of a myoelectric robotic arm during uninterrupted use by an amputee subject and able-bodied subjects.Clinical Relevance: Adaptive control using real-time prediction learning has the potential to help decrease both the time and the cognitive load required by amputees in real-world functional situations when using myoelectric prostheses. [ABSTRACT FROM AUTHOR]

Background: Although targeted muscle reinnervation has been shown to be effective in enhancing prosthetic control for upper limb amputees, restored hand sensations have been variable. An understanding of possible sensory feedback channels is crucial in working toward more effective closed-loop prosthetic control.Objectives: To compare sensory outcomes of different targeted sensory reinnervation approaches.Study Design: Case series, cross-sectional, and retrospective.Methods: Three transhumeral amputees that had undergone different sensory reinnervation approaches were recruited. Skin pressure sensitivity thresholds and anatomic sensory mapping were performed using Semmes-Weinstein monofilaments. The clinical charts of the subjects were reviewed to compare the sensory maps performed during the earlier post-reinnervation period.Results: While the first two subjects achieved return of hand sensations on the stump skin in early follow-up, the maps showed attenuation over time. The last subject developed discrete sensations of all digits in the recipient cutaneous nerve territories away from the reinnervated muscles.Conclusions: These findings confirm that it is feasible to restore hand sensation after transhumeral targeted reinnervation, but there is a significant intersubject variability. The intrafascicular approach may be particularly effective in restoring digit sensation and deserves further exploration, as do factors affecting stability of the hand maps over time.Clinical Relevance: In addition to enabling intuitive motor control of myoelectric prosthesis, targeted reinnervation can also result in sensory restoration of the hand. Documentation of sensory mapping present after reinnervation may assist with exploring future techniques for sensory enhancement, with the goal of working toward closed-loop prosthetic control. [ABSTRACT FROM AUTHOR]

Background: Carpal tunnel syndrome (CTS) is the most common form of peripheral nerve injury, affecting approximately 3 % of the population. While surgery is effective in mild and moderate cases, nerve and functional recovery are often not complete in severe cases. Therefore, there is a need for adjuvant methods to improve nerve regeneration in those cases. Acetyl-L-carnitine (ALCAR) is involved in lipid transport, vital for mitochondrial function. Although it has been shown to be effective in various forms of neuropathies, it has not been used in traumatic or compressive peripheral nerve injury.Methods: In this pilot study we will utilize a double-blind, randomized, placebo-controlled design. Inclusion criteria will include adult patients with severe CTS. This will be confirmed by nerve conduction studies and motor unit number estimation (MUNE). Only those with severe motor unit loss in the thenar muscles (2 standard deviations [SD] below the mean for the age group) will be included. Eligible patients will be randomized to receive 3,000 mg/day of ALCAR orally or placebo following carpal tunnel release surgery for 2 months. The primary outcome will be MUNE with supplementary secondary outcome measures that include: 1) two-point discrimination; 2) Semmes-Weinstein monofilaments for pressure sensitivity; 3) cold and pain threshold for small fiber function; 4) Boston self-assessment Carpal Tunnel Questionnaire and 5) Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire for symptom severity; and 6) Purdue Pegboard Test for hand functional performance. To follow post treatment recovery and monitor safety, patients will be seen at 3 months, 6 months and 1 year. The outcome measures will be analyzed using two-way ANOVA, with treatment assignment and time points being the independent factors. If significant associations are detected, a post hoc analysis will be completed. We aim to recruit ten patients into each of the two groups. Data from this pilot will provide the basis for power calculation for a full-scale trial.Discussion: ALCAR is a physiologic peptide crucial for fatty acid transport. ALCAR has been shown to be effective in neuroprotection in the central nervous system and increase peripheral nerve regeneration. This has been applied clinically to various systemic peripheral neuropathies including diabetic neuropathy, antiretroviral toxic neuropathy, and chemotherapy-induced peripheral neuropathy. While animal evidence exists for the benefit of ALCAR in compression neuropathy, there have been no human studies to date. This trial will represent the first use of ALCAR in peripheral nerve injury/compression neuropathy.Trial Registration: NCT02141035 ; 20 April 2015. [ABSTRACT FROM AUTHOR]

Introduction: In compressive neuropathies, large myelinated nerve fibers are generally thought to be more susceptible. In this study, we investigated small myelinated Aδ and unmyelinated C fiber function in patients with mild, moderate, and severe carpal tunnel syndrome.Methods: Forty-four healthy controls and 81 carpal tunnel syndrome patients in the mild, moderate, or severe categories were recruited. Small fiber sensation in the affected hand was determined with quantitative sensory testing.Results: Cold detection thresholds in the severe carpal tunnel syndrome group (18.9 ± 6.8°C) were significantly impaired compared with controls (27.2 ± 2.1°C) (P < 0.01). Similarly, warm detection thresholds were also impaired in the severe carpal tunnel syndrome group (41.2 ± 3.5°C) compared with control (37.1 ± 2.1°C) (P < 0.01).Conclusions: These results support the growing body of evidence that carpal tunnel syndrome can affect small afferent fibers. Muscle Nerve 56: 814-816, 2017. [ABSTRACT FROM AUTHOR]

Background: Shoulder pain and dysfunction are common after oncologic neck dissection for head and neck cancer (HNC), due to traction, compression, and devascularization injuries to the spinal accessory nerve (SAN). Shoulder pain and dysfunction can hinder postoperative rehabilitation and hygiene, activities of daily living (ADLs), and return to work after treatment for HNC. Due to the rising incidence of human papillomavirus (HPV)-associated oropharyngeal cancer, patients are often diagnosed in the third or fourth decade of life, leaving many potential working years lost if shoulder dysfunction occurs. Brief electrical stimulation (BES) is a novel technique that has been shown to enhance and accelerate neuronal regeneration after injury through a brain-derived neurotrophic growth factor (BDNF)-driven molecular pathway in multiple peripheral nerves in both humans and animals. Methods/Design: This is a randomized controlled trial testing the effect of intraoperative BES on postoperative shoulder pain and dysfunction. All adult participants with a new diagnosis of HNC undergoing surgery with neck dissection, including Level IIb and postoperative radiotherapy, will be enrolled. Participants will undergo intraoperative BES after completion of neck dissection for 60 min continuously at 20 Hz, 3 to 5 V, in 100-msec pulses. Postoperatively, participants will be evaluated using the Constant-Murley Shoulder Score, a scale that assesses shoulder pain, ADLs, strength, and range of motion. Secondary outcomes measured will include nerve conduction studies (NCS) and electromyographic (EMG) studies, as well as scores on the Oxford Shoulder Score (OSS), the Neck Dissection Impairment Index (NDII), and the University of Washington Quality of Life (UW-QOL) score. Primary and secondary outcomes will be assessed at 6 weeks, 3 months, 6 months, and 12 months. Discussion: The objective of this study is to evaluate the effect of BES on postoperative clinical and objective shoulder functional outcomes and pain after oncologic neck dissection. BES has been shown to be successful in accelerating peripheral nerve regeneration in both animal and human participants in multiple different peripheral nerves. If successful, this technique may provide an adjunctive prevention option for shoulder pain and dysfunction in HNC patients. Trial registration: NCT02268344: 17 October 2014. [ABSTRACT FROM AUTHOR]

Objective Brief postsurgical electrical stimulation (ES) has been shown to enhance peripheral nerve regeneration in animal models following axotomy and crush injury. However, whether this treatment is beneficial in humans with sensory nerve injury has not been tested. The goal of this study was to test the hypothesis that ES would enhance sensory nerve regeneration following digital nerve transection compared to surgery alone. Methods Patients with complete digital nerve transection underwent epineurial nerve repair. After coaptation of the severed nerve ends, fine wire electrodes were implanted before skin closure. Postoperatively, patients were randomized to receiving either 1 hour of 20Hz continuous ES or sham stimulation in a double-blinded manner. Patients were followed monthly for 6 months by a blinded evaluator to monitor physiological recovery of spatial discrimination, pressure threshold, and quantitative small fiber sensory testing. Functional disability was measured using the Disability of Arm, Shoulder, and Hand questionnaire. Results A total of 36 patients were recruited, with 18 in each group. Those in the ES group showed consistently greater improvements in all sensory modalities by 5 to 6 months postoperatively compared to the controls. Although there was a trend of greater functional improvements in the ES group, it was not statistically significant ( p > 0.01). Interpretation Postsurgical ES enhanced sensory reinnervation in patients who sustained complete digital nerve transection. The conferred benefits apply to a wide range of sensory functions. Ann Neurol 2015;77:996-1006 [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: Numerous methods for motor unit number estimation (MUNE) have been developed. The objective of this article is to summarize and compare the major methods and the available data regarding their reproducibility, validity, application, refinement, and utility. Methods: Using specified search criteria, a systematic review of the literature was performed. Reproducibility, normative data, application to specific diseases and conditions, technical refinements, and practicality were compiled into a comprehensive database and analyzed. Results: The most commonly reported MUNE methods are the incremental, multiple-point stimulation, spike-triggered averaging, and statistical methods. All have established normative data sets and high reproducibility. MUNE provides quantitative assessments of motor neuron loss and has been applied successfully to the study of many clinical conditions, including amyotrophic lateral sclerosis and normal aging. Conclusions: MUNE is an important research technique in human subjects, providing important data regarding motor unit populations and motor unit loss over time. Muscle Nerve 50: 884-893, 2014 [ABSTRACT FROM AUTHOR]

We present a case study of a novel variation of the targeted sensory reinnervation technique that provides additional control over sensory restoration after transhumeral amputation. The use of intraoperative somatosensory evoked potentials on individual fascicles of the median and ulnar nerves allowed us to specifically target sensory fascicles to reroute to target cutaneous nerves at a distance away from anticipated motor sites in a transhumeral amputee. This resulted in restored hand maps of the median and ulnar nerve in discrete spatially separated areas. In addition, the subject was able to use native and reinnervated muscle sites to control a robotic arm while simultaneously sensing touch and force feedback from the robotic gripper in a physiologically correct manner. This proof of principle study is the first to demonstrate the ability to have simultaneous dual flow of information (motor and sensory) within the residual limb. In working towards clinical deployment of a sensory integrated prosthetic device, this surgical method addresses the important issue of restoring a usable access point to provide natural hand sensation after upper limb amputation. [ABSTRACT FROM AUTHOR]

The objective of this article is to provide a systematic review of the efficacy of electrical stimulation in healing pressure ulcer and to review its mechanism of action. The Cochrane Library, Pub Med, CINAHL, Medline, EMBASE, and NHS EED were searched for relevant interventional studies including randomized controlled trials ( RCTs) and observational studies. A best-evidence synthesis was performed to summarize the results of the included studies. A total of seven RCTs and two observational studies met the inclusion criteria. Moderate level of evidence of efficacy with low risk of bias was shown in all seven RCTs. Although some studies have used continuous direct current, most other investigators opted to use high-voltage pulsed current to minimize the risk of skin burn and to achieve greater current penetration. Overall, the incidence of adverse effects was very low. Two studies that assessed the economic impacts of electrical stimulation revealed substantial health care cost savings. The mechanisms through which electrical stimulation exerts a positive effect on pressure ulcer healing are reasonably well established. Clinical trials have revealed a moderate level of evidence to support its use as an ancillary treatment modality for healing pressure ulcer. Recommendations regarding the optimal electrical stimulation parameters and dosage of use are provided. Further studies to investigate potential barriers that may impede widespread use in different clinical settings are needed. [ABSTRACT FROM AUTHOR]

The article focuses on validated tests to quantify hand function impairment due to carpal tunnel syndrome (CTS). It states that the aim of the study was to test the validity and reliability of the Purdue Pegboard Test (PPT) in CTS patients. It reports that CTS severity was determined based on electrophysiologic parameters and the Levine Self-Assessment Questionnaire. It concluded that the PPT is a valid and reliable tool to quantify functional impairment caused by CTS.

Even though injection of corticosteroids into the carpal tunnel alleviates the symptoms of mild to moderately severe carpal tunnel syndrome (CTS), it has not gained universal popularity due to its invasiveness. This study was designed to investigate the effectiveness of dexamethasone iontophoresis as a noninvasive method of treating CTS. We carried out a double-blind randomized controlled trial comparing six sessions of iontophoresis with 0.4% dexamethasone sodium phosphate with distilled water in 17 patients. Outcome measures including nerve conduction studies, the Levine Self-Assessment Questionnaire, and the Semmes-Weinstein Monofilaments were done monthly for 6 months after intervention. Most of the outcome measures did not show any significant change following treatment. Although there was subjective improvement of symptom severity scores in the treatment group as quantified by the Levine Self-Assessment Questionnaire, similar improvement was also observed in the control group ( P < 0.05). Although corticosteroid iontophoresis is feasible in clinical settings and is well-tolerated by patients, iontophoresis of 0.4% dexamethasone was not effective in the treatment of mild to moderate CTS. Muscle Nerve 39: 627-633, 2009 [ABSTRACT FROM AUTHOR]

The Moberg Pick-Up Test is a standardized test for assessing hand dexterity. Although reduction of sensation in the hand occurs with aging, the effect of age on a subject's performance of the Moberg Pick-Up Test has not been examined. The primary goal of this study was to examine the impact of aging and, secondarily, the impact of gender and handedness, on performance of the Moberg Pick-Up Test in 116 healthy subjects. The average time to complete each of the four subsets of the test was analyzed using the Kruskal-Wallis, Mann-Whitney U, and Wilcoxon signed-rank tests. The results show that hand dexterity of the subjects was significantly affected by age, with young subjects being the fastest and elderly subjects the slowest. Women accomplished the test faster than men, and task performance with the dominant hand was faster than with the non-dominant hand. Use of normative values established based on age and gender is a valuable objective tool to gauge hand function in patients with different neurologic disorders. Muscle Nerve, 2007 [ABSTRACT FROM AUTHOR]

Postoperative electrical stimulation (PES) improves nerve regeneration by decreasing staggered regeneration at the coaptation site. By contrast, conditioning (preoperative) electrical stimulation (CES) accelerates axon extension. Given that both techniques can be delivered at the bedside, a direct comparison of outcomes is of significant clinical importance. In this study, we compared regeneration and reinnervation outcomes of CES, PES, a combination of CES and PES, and a no stimulation control. Sprague Dawley rats were randomly divided into i) CES, ii) PES, iii) CES + PES, and iv) no stimulation. CES was delivered one week prior to nerve cut/coaptation, and PES was delivered immediately following nerve repair. Length of nerve regeneration was assessed at 7 days post-coaptation (n = 6/cohort), and behavioral testing was performed between 6 and 8 weeks post-coaptation (n = 8/cohort). Animals treated with CES had significantly longer axon extension and improved sensorimotor recovery compared to all other cohorts. CES treated axons extended 8.5 ± 0.6 mm, significantly longer than PES (5.5 ± 0.5 mm), CES + PES (3.6 ± 0.7 mm), or no stimulation (2.7 ± 0.5 mm) (p <.001). Sensory recovery (von Frey filament testing, intraepidermal nerve fiber reinnervation) (p <.001) and motor reinnervation (horizontal ladder, gait analysis, nerve conduction studies, neuromuscular junction analysis) (p <.05 - p <.001) were significantly improved in CES animals. CES significantly improves regeneration and reinnervation beyond the current clinical paradigm of PES. The combination of CES and PES does not have a synergistic effect. CES alone therefore may be a more promising treatment to improve outcomes in patients undergoing nerve repair surgeries. • CES accelerates nerve regeneration greater than PES or a combination of CES + PES. • CES promotes sensorimotor functional recovery greater than PES and CES + PES. • CES + PES did not have a synergistic effect to promote nerve regeneration. [ABSTRACT FROM AUTHOR]

Peripheral nerve injuries are common and frequently result in incomplete functional recovery even with optimal surgical treatment. Permanent motor and sensory deficits are associated with significant patient morbidity and socioeconomic burden. Despite substantial research efforts to enhance peripheral nerve regeneration, few effective and clinically feasible treatment options have been found. One promising strategy is the use of low frequency electrical stimulation delivered perioperatively to an injured nerve at the time of surgical repair. Possibly through its effect of increasing intraneuronal cyclic AMP, perioperative electrical stimulation accelerates axon outgrowth, remyelination of regenerating axons, and reinnervation of end organs, even with delayed surgical intervention. Building on decades of experimental evidence in animal models, several recent, prospective, randomized clinical trials have affirmed electrical stimulation as a clinically translatable technique to enhance functional recovery in patients with peripheral nerve injuries requiring surgical treatment. This paper provides an updated review of the cellular physiology of electrical stimulation and its effects on axon regeneration, Level I evidence from recent prospective randomized clinical trials of electrical stimulation, and ongoing and future directions of research into electrical stimulation as a clinically feasible adjunct to surgical intervention in the treatment of patients with peripheral nerve injuries. [ABSTRACT FROM AUTHOR]

Background While some patients with low back pain demonstrate increased spinal stiffness that decreases as pain subsides, this observation is inconsistent. Currently, the relation between spinal stiffness and low back pain remains unclear. This study aimed to investigate the effects of experimental low back pain on temporal changes in posteroanterior spinal stiffness and concurrent trunk muscle activity. Method In separate sessions five days apart, nine asymptomatic participants received equal volume injections of hypertonic or isotonic saline in random order into the L3–L5 interspinous ligaments. Pain intensity, spinal stiffness (global and terminal stiffness) at the L3 level, and the surface electromyographic activity of six trunk muscles were measured before, immediately after, and 25-minute after injections. These outcome measures under different saline conditions were compared by generalized estimating equations. Findings Compared to isotonic saline injections, hypertonic saline injections evoked significantly higher pain intensity (mean difference: 5.7/10), higher global (mean difference: 0.73 N/mm) and terminal stiffness (mean difference: 0.58 N/mm), and increased activity of four trunk muscles during indentation ( P < 0.05). Both spinal stiffness and trunk muscle activity returned to baseline levels as pain subsided. Interpretation While previous clinical research reported inconsistent findings regarding the association between spinal stiffness and low back pain, our study revealed that experimental pain caused temporary increases in spinal stiffness and concurrent trunk muscle co-contraction during indentation, which helps explain the temporal relation between spinal stiffness and low back pain observed in some clinical studies. Our results substantiate the role of spinal stiffness assessments in monitoring back pain progression. [ABSTRACT FROM AUTHOR]