Inter- and intra-tester reliability of sensibility testing in digital nerve repair

Berberine inhibits NLRP3 inflammasome activation and proinflammatory macrophage M1 polarization to accelerate peripheral nerve regeneration

Berberine (BBR) has demonstrated potent anti-inflammatory effects by modulating macrophage polarization. Nevertheless, the precise mechanisms through which berberine regulates post-injury inflammation within the peripheral nerve system remain elusive. This study seeks to elucidate the role of BBR and its underlying mechanisms in inflammation following peripheral nerve injury (PNI). Adult male C57BL/6J mice subjected to PNI were administered daily doses of berberine (0, 60, 120, 180, 240 ​mg/kg) via gavage from day 1 through day 28. Evaluation of the sciatic function index (SFI) and paw withdrawal threshold revealed that BBR dose-dependently enhanced both motor and sensory functions. Immunofluorescent staining for anti-myelin basic protein (anti-MBP) and anti-neurofilament-200 (anti-NF-200), along with histological staining comprising hematoxylin-eosin (HE), luxol fast blue (LFB), and Masson staining, demonstrated that BBR dose-dependently promoted structural regeneration. Molecular analyses including qRT-PCR, Western blotting, enzyme-linked immunosorbent assay (ELISA), and immunofluorescence confirmed that inactivation of the NLRP3 inflammasome by MCC950 shifted macrophages from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype, while also impeding macrophage infiltration. Furthermore, BBR significantly downregulated the expression of the NLRP3 inflammasome and its associated molecules in macrophages, thereby mitigating NLRP3 inflammasome activation-induced macrophage M1 polarization and inflammation. In summary, BBR's neuroprotective effects were concomitant with the suppression of inflammation after PNI, achieved through the inhibition of NLRP3 inflammasome activation-induced macrophage M1 polarization.

Precise Monitoring of Returning Sensation in Digital-Nerve Lesions by Three-Dimensional Imaging: A Proof-of-Concept Study

SUMMARY

Digital-nerve lesions result in a loss of tactile sensation reflected by an anesthetic area (AA) at the radial or ulnar aspect of the respective digit. Available tools to monitor the recovery of tactile sense have been criticized for their lack of validity. Precise quantification of AA dynamics by three-dimensional (3D) imaging could serve as an accurate surrogate to monitor recovery after digital-nerve repair. For validation, AAs were marked on digits of healthy volunteers to simulate the AA of an impaired cutaneous innervation. The 3D models were composed from raw images that had been acquired with a 3D camera to precisely quantify relative AA for each digit (3D models, n = 80). Operator properties varied with regard to individual experience in 3D imaging and image processing. In addition, the concept was applied in a clinical case study. Results showed that images taken by experienced photographers were rated as better quality ( P < 0.001) and needed less processing time ( P = 0.020). Quantification of the relative AA was not altered significantly, regardless of experience level of the photographer ( P = 0.425) or image assembler ( P = 0.749). The proposed concept allows precise and reliable surface quantification of digits and can be performed consistently without relevant distortion by lack of examiner experience. Routine 3D imaging of the AA has the great potential to provide visual evidence of various returning states of sensation and to convert sensory nerve recovery into a metric variable with high responsiveness to temporal progress.

Advanced practice occupational therapy led triage and treatment clinic for patients with carpal tunnel syndrome in an Irish public hospital

INTRODUCTION

A pilot CTS Triage and Treat clinic led by an Advanced Practice Occupational Therapist was established to address the CTS wait list at a large urban hospital. The aims of this pilot were to develop a clinical triage and screening protocol to inform the stratification of patients for suitable treatment options and to reduce waiting time.

METHODS

A cross sectional study with follow up was conducted, patients on the wait list at time of commencement of the pilot and subsequent referrals over a 1-year period were recruited. Triage consisted of tests of sensibility, self-rating measures, provocative tests and detailed patient to inform the subsequent treatment stratification, conservative, injection, surgery, or further investigation. Nonparametric analyses were used to test relationships between the test scores and to complete subgroup comparisons.

RESULTS

Eighty-nine patients were triaged over the pilot period, 62 (70%) had a positive Phalen's at triage. Following triage 48 (54%) patients were stratified for conservative management, injection (n = 23, 26%) and surgery/differential diagnosis (n = 18, 20%). Statistically significant differences in BCTQ (SSS and FSS) and Q-DASH scores were noted across the three outcome groups, with lower scores among those commenced on conservative management. BCTQ (SSS) scores were aligned with the Semmes Weinstein Monofilaments sensibility thresholds. Wait times showed a marked decrease from 10 to 2 months over the period of the pilot.

DISCUSSION

Findings highlight the positive impact of occupational therapy led triage and treat approach in the reduction of wait time for assessment and treatment for patients with CTS.

Down-regulation miR-146a-5p in Schwann cell-derived exosomes induced macrophage M1 polarization by impairing the inhibition on TRAF6/NF-κB pathway after peripheral nerve injury

BACKGROUND

Both Schwann cell-derived exosomes (SC-Exos) and macrophagic sub-phenotypes are closely related to the regeneration and repair after peripheral nerve injury (PNI). However, the crosstalk between them is less clear.

OBJECTIVE

We aim to investigate the roles and underlying mechanisms of exosomes from normoxia-condition Schwann cell (Nor-SC-Exos) and from post-injury oxygen-glucose-deprivation-condition Schwann cell in regulating macrophagic sub-phenotypes and peripheral nerve injury repair.

METHOD

Both Nor-SC-Exos and OGD-SC-Exos were extracted through ultracentrifugation, identified by transmission electron microscopy (TEM), Nanosight tracking analysis (NTA) and western blotting. High-throughput sequencing was performed to explore the differential expression of microRNAs in both SC-Exos. In vitro, RAW264.7 macrophage was treated with two types of SC-Exos, M1 macrophagic markers (IL-10, Arg-1, TGF-β1) and M2 macrophagic markers (IL-6, IL-1β, TNF-α) were detected by enzyme-linked Immunosorbent Assay (ELISA) or qRT-PCR, and the expression of CD206, iNOS were detected via cellular immunofluorescence (IF) to judge macrophage sub-phenotypes. Dorsal root ganglion neurons (DRGns) were co-cultured with RAW264.7 cells treated with Nor-SC-Exos and OGD-SC-Exos, respectively, to explore their effect on neuron growth. In vivo, we established a sciatic nerve crush injury rat model. Nor-SC-Exos and OGD-SC-Exos were locally injected into the injury site. The mRNA expression of M1 macrophagic markers (IL-10, Arg-1, TGF-β1) and M2 macrophagic markers (IL-6, IL-1β, TNF-α) were detected by qRT-PCR to determine the sub-phenotype of macrophages in the injury site. IF was used to detect the expression of MBP and NF200, reflecting the myelin sheath and axon regeneration, and sciatic nerve function index (SFI) was measured to evaluate function repair.

RESULT

In vitro, Nor-SC-Exos promoted macrophage M2 polarization, increased anti-inflammation factors secretion, and facilitated axon elongation of DRGns. OGD-SC-Exos promoted M1 polarization, increased pro-inflammation factors secretion, and restrained axon elongation of DRGns. High-throughput sequencing and qRT-PCR results found that compared with Nor-SC-Exos, a shift from anti-inflammatory (pro-M2) to pro-inflammatory (pro-M1) of OGD-SC-Exos was closely related to the down-regulation of miR-146a-5p and its decreasing inhibition on TRAF6/NF-κB pathway after OGD injury. In vivo, we found Nor-SC-Exos and miR-146a-5p mimic promoted regeneration of myelin sheath and axon, and facilitated sciatic function repair via targeting TRAF6, while OGD-SC-Exos and miR-146a-5p inhibitor restrained them.

CONCLUSION

Our study confirmed that miR-146a-5p was significantly decreased in SC-Exos under the ischemia-hypoxic microenvironment of the injury site after PNI, which mediated its shift from promoting macrophage M2 polarization (anti-inflammation) to promoting M1 polarization (pro-inflammation), thereby limiting axonal regeneration and functional recovery.

Psychometric properties of light touch-pressure somatosensory measures in adults with neurological disorders: A systematic review

OBJECTIVES

To critically appraise the psychometric properties of light touch-pressure somatosensory assessments to provide guidance for tool selection for research or clinical purposes.

DATA SOURCES

MEDLINE, CINAHL, and PsycInfo were searched for research indexed from January 1990-November 2022. English language and human subject filters were applied. "Somatosensation", "psychometric property", and "nervous system-based health condition" search terms were combined. Grey literature and manual searches were conducted to ensure thoroughness.

REVIEW METHODS

The reliability, construct validity, and/or measurement error of light touch-pressure assessments was reviewed in adult populations with neurological disorders. Reviewers individually extracted and managed data including patient demographics, assessment characteristics, statistical methods, and psychometric properties. Methodological quality of results was evaluated using an adapted version of the COnsensus-based Standards for the selection of health Measurement INstruments checklist.

RESULTS

Thirty-three of 1938 articles were included for review. Fifteen light touch-pressure assessments demonstrated good or excellent reliability. Further, five of those 15 assessments achieved adequate validity and one of the 15 assessments achieved adequate measurement error. Over 80% of the summarized study ratings were determined to be of low or very low quality.

CONCLUSION

We recommend using electrical perceptual tests, the Semmes-Weinstein Monofilaments, the Graded and Redefined Assessment of Strength, Sensibility, and Prehension, and the Moving Touch Pressure Test given that they demonstrated good to excellent results in three psychometric properties. No other assessment achieved adequate ratings in more than two psychometric properties. This review highlights a fundamental need to develop sensory assessments that are reliable, valid, and sensitive to change.

Reliability of Ulnar Nerve Sensation Tests in Patients with Cubital Tunnel Syndrome and Healthy Subjects

Static two-point discrimination (2PD) and Semmes–Weinstein monofilament (SWM) tests are commonly used to evaluate sensory disorders in the hand. The aim of this study was to evaluate the reliability of 2PD and SWM tests in the ulnar nerve innervation area in patients with cubital tunnel syndrome (CuTS) and healthy individuals. This was a two-group repeated-measures inter-rater and intra-rater reliability study. Twenty-one patients with CuTS and 30 healthy adults participated. The static 2PD test was performed using a standardized Dellon discriminator, whereas the SWM test was conducted using TOUCH TEST monofilaments. Two examiners performed both tests at the hypothenar eminence and the fourth and fifth digits (ulnar nerve innervation hand territory). First, examiner A conducted three series of 2PD and SWM tests twice with a 15-min rest period (within-day intra-rater reliability). Next, examiner B repeated the same examination 5 min after (inter-rater reliability). Examiner A conducted the same examination 7 days after (between-day intra-rater reliability). For single measurements, the inter-rater reliability and within-day intra-rater reliability in the 2PD was at least 0.81 in patients with CuTS or healthy subjects. The between-days intra-rater reliability for a single measurement varied from 0.56 to 0.95 in CuTS patients and healthy subjects. The between-days intra-rater reliability for mean value from three measurements was above 0.80. The kappa for SWM was above 0.8 and the percentage of agreement was at least 90% for all sessions and trials. In conclusion, the 2PD and SWM tests are reliable for assessing sensation in the ulnar nerve innervation area of the hand in patients with CuTS and healthy subjects.

Exosomes from LPS-preconditioned bone marrow MSCs accelerated peripheral nerve regeneration via M2 macrophage polarization: Involvement of TSG-6/NF-κB/NLRP3 signaling pathway

Lipopolysaccharide (LPS)-preconditioned mesenchymal stem cells (MSCs) possessed strong immunomodulatory and anti-inflammatory functions by secreting exosomes as major paracrine effectors. However, the specific effect of exosomes from LPS pre-MSCs (LPS pre-Exos) on peripheral nerve regeneration has yet to be documented. Here, we established a sciatic nerve injury model in rats and an inflammatory model in RAW264.7 cells to explore the potential mechanism between LPS pre-Exos and peripheral nerve repair. The local injection of LPS pre-Exos into the nerve injury site resulted in an accelerated functional recovery, axon regeneration and remyelination, and an enhanced M2 Macrophage polarization. Consistent with the data in vivo, LPS pre-Exos were able to shift the pro-inflammation macrophage into a pro-regeneration macrophage. Notably, TNF stimulated gene-6 (TSG-6) was found to be highly enriched in LPS pre-Exos. We obtained si TSG-6 Exo by the knockdown of TSG-6 in LPS pre-Exos to demonstrate the role of TSG-6 in macrophage polarization, and found that TSG-6 served as a critical mediator in LPS pre-Exos-induced regulatory effects through the inhibition of NF-ΚΒ and NOD-like receptor protein 3 (NLRP3). In conclusion, our findings suggested that LPS pre-Exos promoted macrophage polarization toward an M2 phenotype by shuttling TSG-6 to inactivate the NF-ΚΒ/NLRP3 signaling axis, and could provide a potential therapeutic avenue for peripheral nerve repair.

Research reporting in cubital tunnel syndrome studies: an analysis of the literature

PURPOSE

There is a strong need for a set of consensus outcomes to be utilized for future studies on cubital tunnel syndrome. The goal was to assess the outcome measures utilized in the cubital tunnel syndrome literature as a way of measuring popularity/acceptability and then to perform a literature review for the most commonly used outcomes.

METHODS

A literature search was performed using the pubmed.gov database and Medical Subject Headings (MeSH). For each article, the following data were abstracted: study type, motor outcome(s), sensory outcome(s), composite outcome(s), patient-reported outcome (PRO) metric(s), pain outcome(s), psychological outcome(s), electrodiagnostic outcome(s), and any other outcomes that were used.

RESULTS

A composite outcome was reported in 52/85 (61%) studies, with the modified Bishop score (27/85; 32%) most common. A motor outcome was reported in 44/85 (52%) studies, with dynamometry (38/85; 45%) most common. The majority of studies (55%) did not report a sensory outcome. The majority of studies (52%) did not report a PRO. A specific pain outcome was reported in the minority (23/85; 27%), with the visual analogue scale (VAS) (22/85; 26%) most common. Pre- and postoperative electrodiagnostic results were presented in 22/85 studies (26%).

DISCUSSION

Understanding current clinical practice and historical outcomes reporting provides a foundation for discussion regarding the development of a core outcome set for cubital tunnel syndrome. We hope that the data provided in the current study will stoke a discussion that will culminate in a consensus statement for research reporting in cubital tunnel syndrome studies.

Wearable vibrotactile stimulation for upper extremity rehabilitation in chronic stroke: clinical feasibility trial using the VTS Glove

OBJECTIVE

Evaluate the feasibility and potential impacts on hand function using a wearable stimulation device (the VTS Glove) which provides mechanical, vibratory input to the affected limb of chronic stroke survivors.

METHODS

A double-blind, randomized, controlled feasibility study including sixteen chronic stroke survivors (mean age: 54; 1-13 years post-stroke) with diminished movement and tactile perception in their affected hand. Participants were given a wearable device to take home and asked to wear it for three hours daily over eight weeks. The device intervention was either (1) the VTS Glove, which provided vibrotactile stimulation to the hand, or (2) an identical glove with vibration disabled. Participants were randomly assigned to each condition. Hand and arm function were measured weekly at home and in local physical therapy clinics.

RESULTS

Participants using the VTS Glove showed significantly improved Semmes-Weinstein monofilament exam results, reduction in Modified Ashworth measures in the fingers, and some increased voluntary finger flexion, elbow and shoulder range of motion.

CONCLUSIONS

Vibrotactile stimulation applied to the disabled limb may impact tactile perception, tone and spasticity, and voluntary range of motion. Wearable devices allow extended application and study of stimulation methods outside of a clinical setting.

Endogenous Neurostimulation and Physiotherapy in Cluster Headache: A Clinical Case

OBJECTIVE

The aim of this paper is to describe the progressive changes of chronic cluster headaches (CHs) in a patient who is being treated by a multimodal approach, using pharmacology, neurostimulation and physiotherapy.

SUBJECT

A male patient, 42 years of age was diagnosed with left-sided refractory chronic CH by a neurologist in November 2009. In June 2014, the patient underwent a surgical intervention in which a bilateral occipital nerve neurostimulator was implanted as a treatment for headache.

METHODS

Case report.

RESULTS

Primary findings included a decreased frequency of CH which lasted up to 2 months and sometimes even without pain. Besides this, there were decreased levels of anxiety, helplessness (PCS subscale) and a decreased impact of headache (HIT-6 scale). Bilateral pressure pain thresholds (PPTs) were improved along with an increase in strength and motor control of the neck muscles. These improvements were present at the conclusion of the treatment and maintained up to 4 months after the treatment.

CONCLUSIONS

A multimodal approach, including pharmacology, neurostimulation and physiotherapy may be beneficial for patients with chronic CHs. Further studies such as case series and clinical trials are needed to confirm these results.

Liposuction Aspirate Fluid Adipose-Derived Stem Cell Injection and Secondary Healing in Fingertip Injury: A Pilot Study

BACKGROUND

Although fingertip injuries account for a high proportion of trauma patients, the correct surgical approach is still debated. The authors compared the traditional conservative approach and a new treatment based on the injection of liposuction aspirate fluid.

METHODS

Forty consecutive patients with a fingertip injury were dichotomized into group A (control group; conservative approach) and group B (treatment group). Group B underwent liposuction, followed by filtration of the lipoaspirate in a closed device (MyStem EVO kit), allowing the nonenzymatic separation of liposuction aspirate fluid, which was then injected at the site of injury. Objective outcomes were time for healing, strength, mobility of joint, and touch and sensory function. Subjective outcomes were cold intolerance, pain, hand disability, and aesthetic result. An aliquot of liposuction aspirate fluid was sent to the laboratory for cellular isolation and analysis by flow cytometry and in vitro differentiation assays.

RESULTS

The average healing time was 22.3 days in group B and 24.9 days in group A (p < 0.05). Eighty-five percent of group B patients and 67 percent of group A patients scored normal to diminished superficial sensibility (p < 0.05). Group A had higher pain and cold intolerance scores (p < 0.05). Group B scored greater aesthetic and disabilities outcome results (p < 0.05). The cell isolation yield was 8.3 × 10(5)/ml, with a percentage of viable cells of 74.3 percent. Flow cytometry identified a mesenchymal immunophenotype, and in vitro osteogenic and adipogenic induction confirmed the bilinear potential of the isolated cells.

CONCLUSION

This clinical study demonstrates for the first time the regenerative potential of liposuction aspirate fluid adipose-derived stem cells in a clinical application.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Exosomes and Their MicroRNA Cargo: New Players in Peripheral Nerve Regeneration

Peripheral nerve injury is a major clinical problem and often results in a poor functional recovery. Despite obvious clinical need, treatment strategies have been largely suboptimal. In the nervous system, exosomes, which are nanosized extracellular vesicles, play a critical role in mediating intercellular communication. More specifically, microRNA carried by exosomes are involved in various key processes such as nerve and vascular regeneration, and exosomes originating from Schwann cells, macrophages, and mesenchymal stem cells can promote peripheral nerve regeneration. In this review, the current knowledge of exosomes' and their miRNA cargo's role in peripheral nerve regeneration are summarized. The possible future roles of exosomes in therapy and the potential for microRNA-containing exosomes to treat peripheral nerve injuries are also discussed.

Inter- and intra-tester reliability of sensibility testing in healthy individuals

Static two-point discrimination (S2PD) and Semmes-Weinstein monofilament (SWM) tests are the most widely used tests for evaluation of sensory deterioration. It is a necessity to know the inter- and intra-tester reliability of these tests to determine the suitability of method. Another important point in evaluation of sensory deterioration is whether or not there is a reference point which can be compared with the test results. So, it is important to know the reliability of sensory evaluation tests on the healthy extremities. The aim of this study was to evaluate the inter- and intra-tester reliability of the S2PD and SWM tests applied to the fingers of healthy individuals. One hundred and sixty three healthy fingers from 83 individuals were included into the study. An experienced orthopaedic surgeon and a physiotherapist examined all the individuals separately. The reliability of the S2PD test was found to be little and low. The reliability of the SWM test was determined as low and moderate. The reproducibility scores of both tests were at a poor level. Therefore, in the evaluation of states with sensory deterioration, the use of the healthy contralateral extremities as a standard reference point could be considered unreliable. Prognosis, grading or follow-up of treatment should not be made according to the results of the S2PD and SWM tests only. It would be more correct to use these tests as a diagnostic tool rather than quantitative follow-up for neurological function in pathological conditions.