Emerging Relationships between Exercise, Sensory Nerves, and Neuropathic Pain

From inflammatory signaling to neuronal damage: Exploring NLR inflammasomes in ageing neurological disorders

The persistence of neuronal degeneration and damage is a major obstacle in ageing medicine. Nucleotide-binding oligomerization domain (NOD)-like receptors detect environmental stressors and trigger the maturation and secretion of pro-inflammatory cytokines that can cause neuronal damage and accelerate cell death. NLR (NOD-like receptors) inflammasomes are protein complexes that contain NOD-like receptors. Studying the role of NLR inflammasomes in ageing-related neurological disorders can provide valuable insights into the mechanisms of neurodegeneration. This includes investigating their activation of inflammasomes, transcription, and capacity to promote or inhibit inflammatory signaling, as well as exploring strategies to regulate NLR inflammasomes levels. This review summarizes the use of NLR inflammasomes in guiding neuronal degeneration and injury during the ageing process, covering several neurological disorders such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, stroke, and peripheral neuropathies. To improve the quality of life and slow the progression of neurological damage, NLR-based treatment strategies, including inhibitor-related therapies and physical therapy, are presented. Additionally, important connections between age-related neurological disorders and NLR inflammasomes are highlighted to guide future research and facilitate the development of new treatment options.

The Role of Physical Exercise in Chronic Musculoskeletal Pain: Best Medicine-A Narrative Review

The aim of this paper is to provide a narrative review of the effects of physical exercise in the treatment of chronic musculoskeletal pain. Physical inactivity and sedentary behavior are associated with chronic musculoskeletal pain and can aggravate it. For the management of musculoskeletal pain, physical exercise is an effective, cheap, and safe therapeutic option, given that it does not produce the adverse effects of pharmacological treatments or invasive techniques. In addition to its analgesic capacity, physical exercise has an effect on other pain-related areas, such as sleep quality, activities of daily living, quality of life, physical function, and emotion. In general, even during periods of acute pain, maintaining a minimum level of physical activity can be beneficial. Programs that combine several of the various exercise modalities (aerobic, strengthening, flexibility, and balance), known as multicomponent exercise, can be more effective and better adapted to clinical conditions. For chronic pain, the greatest benefits typically occur with programs performed at light-to-moderate intensity and at a frequency of two to three times per week for at least 4 weeks. Exercise programs should be tailored to the specific needs of each patient based on clinical guidelines and World Health Organization recommendations. Given that adherence to physical exercise is a major problem, it is important to empower patients and facilitate lifestyle change. There is strong evidence of the analgesic effect of physical exercise in multiple pathologies, such as in osteoarthritis, chronic low back pain, rheumatoid arthritis, and fibromyalgia.

The role of walking exercise on axonal regrowth and neuropathic pain markers in dorsal root ganglion after sciatic nerve injury

The aim of this study was to determine whether walking exercise can regulate the expression level of neuropathic pain- and inflammatory response markers in the ipsilateral lumbar 4 to 6 dorsal root ganglion neurons after sciatic nerve injury (SNI). The experimental rats were randomly divided into seven groups: the normal control group, sedentary groups for 3, 7, and, 14 days postinjury (dpi), and walking exercise groups for 3, 7, and 14 dpi. Western blot techniques were used to evaluate specific neuropathic pain- and cytokine markers and mechanical allodynia was confirmed by paw withdrawal test. Mechanical allodynia was significantly improved in the walking exercise group compared to the sedentary group at all 7, 10, and 14 dpi. Furthermore, growth associated protein 43 and brain-derived neurotrophic factor levels were significantly increased in the walking exercise groups compared to the sedentary group at all 3, 7, and 14 dpi. Conversely, nuclear factor kappa-light-chain-enhancer of activated B cells, interleukin-6, tumor necrosis factor α, calcitonin gene-related peptide, and c-Fos expression levels were significantly decreased in the walking exercise groups compared to the sedentary group at all 3, 7, and 14 dpi. These findings suggest meaningful information that aggressive rehabilitation walking exercise applied early after SNI might be improve mechanical allodynia, neuropathic pain and inflammatory response markers following SNI.

Exercise therapy including the cervical extensor muscles in individuals with neck pain: A systematic review

OBJECTIVE

To review the use (dosage parameters and combination with other therapeutic interventions) of cervical extensor muscle exercises and their effect on pain, disability (primary outcomes), range of motion, endurance and strength (secondary outcomes) in people with neck pain.

DATA SOURCES

An extensive literature search was conducted through MEDLINE (Ovid), Scopus (Elsevier) and Physiotherapy Evidence Database (PEDro) up to May 2023. The reference lists of all included studies and relevant reviews were screened for additional studies.

REVIEW METHODS

Randomised controlled trials reporting the use of cervical extensor muscle exercises (alone or combined) applied to adults with idiopathic or traumatic neck pain were included. Study selection, data extraction and critical appraisal (PEDro assessment scale) were performed by two blinded reviewers. Data extraction included dosage parameters, other modalities combined with these exercises and outcomes.

RESULTS

Thirty-five randomised controlled trails (eight of which were complementary analyses) with 2409 participants fulfilled the inclusion criteria. Twenty-six were of moderate to high quality. In most studies, cervical extensor muscle exercises were combined with various other therapeutic modalities and applied at different dosages. Only two studies (one high and one low quality) specifically assessed their effectiveness. The high-quality study showed significant improvements in neck pain and disability, pressure point threshold and neck mobility after both low load and high load training for 6 weeks.

CONCLUSION

The results suggest cervical extensor muscle exercises may reduce neck pain and disability; however firm conclusions cannot be drawn because of the few studies that addressed this question and the heterogeneity of the dosage parameters.

Exercise Therapy for Chronic Neck Pain: Tailoring Person-Centred Approaches within Contemporary Management

Exercise therapy is considered the best evidence-based approach for managing chronic neck pain. However, the implementation of exercise therapy presents several challenges. Systematic reviews indicate that it has modest effectiveness, while clinical practice guidelines offer limited guidance on the exercise parameters required to optimise clinical outcomes. Moreover, recommendations often fail to differentiate between different types of neck pain. This article addresses the challenges associated with the prescription of exercise for chronic neck pain and provides recommendations for exercise therapy specific to chronic nociceptive, neuropathic, and nociplastic neck pain. The goal of this article is to facilitate the implementation of high-value evidence-based exercise therapy for these distinct types of chronic neck pain with the aim to improve its outcomes and to reduce the related individual and societal burdens.

The potential protective effects of pre-injury exercise on neuroimmune responses following experimentally-induced traumatic neuropathy: a systematic review with meta-analysis

Pre-clinical evidence shows that neuropathy is associated with complex neuroimmune responses, which in turn are associated with increased intensity and persistence of neuropathic pain. Routine exercise has the potential to mitigate complications of future nerve damage and persistence of pain through neuroimmune regulation. This systematic review aimed to explore the effect of pre-injury exercise on neuroimmune responses, and other physiological and behavioural reactions following peripheral neuropathy in animals. Three electronic databases were searched from inception to July 2022. All controlled animal studies assessing the influence of an active exercise program prior to experimentally-induced traumatic peripheral neuropathy compared to a non-exercise control group on neuroimmune, physiological and behavioural outcomes were selected. The search identified 17,431 records. After screening, 11 articles were included. Meta-analyses showed that pre-injury exercise significantly reduced levels of IL-1β (SMD: -1.06, 95% CI: -1.99 to -0.13, n=40), but not iNOS (SMD: -0.71 95% CI: -1.66 to 0.25, n=82). From 72 comparisons of different neuroimmune outcomes at different anatomical locations, vote counting revealed reductions in 23 pro-inflammatory and increases in 6 anti-inflammatory neuroimmune outcomes. For physiological outcomes, meta-analyses revealed that pre-injury exercise improved one out of six nerve morphometric related outcomes (G-ratio; SMD: 1.95, 95%CI: 0.77 to 3.12, n=20) and one out of two muscle morphometric outcomes (muscle fibre cross-sectional area; SMD: 0.91, 95%CI: 0.27 to 1.54, n=48). For behavioural outcomes, mechanical allodynia was significantly less in the pre-injury exercise group (SMD -1.24, 95%CI: -1.87 to -0.61) whereas no overall effect was seen for sciatic function index. Post hoc subgroup analysis suggests that timing of outcome measurement may influence the effect of pre-injury exercise on mechanical allodynia. Risk of bias was unclear in most studies, as the design and conduct of the included experiments were poorly reported. Preventative exercise may have potential neuroprotective and immunoregulatory effects limiting the sequalae of nerve injury, but more research in this field is urgently needed.

Association between Pain and Frequent Physical Exercise among Adults in the United States: A Cross-Sectional Database Study

Pain affects over 20% of United States adults, and less than 50% of United States adults participate in frequent physical exercise. This cross-sectional database study included 13,758 United States adults aged >18 years from the 2020 Medical Expenditure Panel Survey (MEPS) and analyzed the association between severity of pain (independent variable) and frequent physical exercise (dependent variable), adjusting for demographic, economic, limitation, and health variables using multivariable logistic regression. The study showed 50.3% of adults report frequently exercising. Only 37.1% of adults reported experiencing pain of any degree, with a majority of them experiencing little pain. In the adjusted model, extreme pain vs. none, quite a bit of pain vs. none, Hispanic vs. non-Hispanic ethnicity, having a functional limitation vs. no limitation, and being overweight/obese vs. not being obese/overweight were associated with lower odds of reporting doing frequent physical exercise. Meanwhile, being ≥65 or 40-64 vs. 18-39 years of age, male vs. female, white vs. not white race, private or public vs. no health coverage, and good vs. poor general health were associated with greater odds of reporting doing frequent physical exercise. These variables associated with frequent physical exercise should be considered in future work when designing health interventions.

Emerging Nonpharmacologic Interventions to Treat Diabetic Peripheral Neuropathy

Significance: Diabetic peripheral neuropathy (DPN), a complication of metabolic syndrome, type I and type II diabetes, leads to sensory changes that include slow nerve conduction, nerve degeneration, loss of sensation, pain, and gate disturbances. These complications remain largely untreatable, although tight glycemic control can prevent neuropathy progression. Nonpharmacologic approaches remain the most impactful to date, but additional advances in treatment approaches are needed. Recent Advances: This review highlights several emerging interventions, including a focus on dietary interventions and physical activity, that continue to show promise for treating DPN. We provide an overview of our current understanding of how exercise can improve aspects of DPN. We also highlight new studies in which a ketogenic diet has been used as an intervention to prevent and reverse DPN. Critical Issues: Both exercise and consuming a ketogenic diet induce systemic and cellular changes that collectively improve complications associated with DPN. Both interventions may involve similar signaling pathways and benefits but also impact DPN through unique mechanisms. Future Directions: These lifestyle interventions are critically important as personalized medicine approaches will likely be needed to identify specific subsets of neuropathy symptoms and deficits in patients, and determine the most impactful treatment. Overall, these two interventions have the potential to provide meaningful relief for patients with DPN and provide new avenues to identify new therapeutic targets.

The Effects of a 10-Week Aerobic and Unilateral Lower Extremity Resistance Training Program on Amplitude and Nerve Conduction Velocity of Sensory and Motor Nerves in Diabetic Patients with Neuropathy

This study aimed to investigate the effects of 10-week aerobic and unilateral lower extremity resistance training on nerve conduction velocity and amplitude of sensory and motor nerves in diabetic patients with neuropathy. This clinical trial was conducted on twenty women and men (aged 30-60 years old) with diabetic neuropathy. Participants were randomly assigned to one of the two groups: an exercise group (EG; n = 10) and a control group (CG; n = 10). The EG performed a 10-week programme with one session of aerobic exercises (40% to 70% of HR reserve), supplemented with one session of specific lower extremity resistance exercises (60-90 min/day) on the same day for four days per week. The CG subjects performed their regular daily activities. The nerve conduction velocity, amplitude of sensory and motor nerves and glycosylated haemoglobin A1c were measured before and after the intervention. The repeated-measures ANOVA showed a significant increase in the conduction velocity of the sural sensory nerve as well as the peroneal motor nerve (p < 0.01, p < 0.01). The changes in the conduction velocity of the tibial nerve were similar when compared to the control group (p > 0.05). A significantly greater decrease in glycosylated haemoglobin was also observed in the EG group (p < 0.01). Performing 10 weeks of aerobic and specific unilateral lower extremity exercises can improve the function of sensory and motor nerves and improve symptoms in diabetic patients with neuropathy. Given the limited studies in this area, the exact mechanisms of this performance improvement need further examination.

Proteomic Analysis of the Spinal Dorsal Horn in Mice with Neuropathic Pain After Exercise

Purpose

Neuropathic pain (NP) is a chronic pain state with a complex etiology that currently lacks effective treatment in clinical practice. Studies have found that exercise training can alleviate NP hyperalgesia, but the specific mechanism remains unclear. Here, we sought to identify proteins and signaling pathways critical for mediating the effects of treadmill training on NP in a mouse model of spared nerve injury (SNI).

Methods

We used Tandem Mass Tag (TMT) technology for proteins and signaling pathways identification. Functional enrichment analyses were conducted using DAVID and Metascape software. Ingenuity pathway analysis was used to conduct functional annotation and analyze alterations in canonical pathways and molecular networks. Reverse transcription quantitative PCR (RT-qPCR) was used to confirm the results of proteomics analysis.

Results

A total of 270 differentially expressed proteins were screened in the detrained and trained groups (P ≤0.05). Enrichment and ingenuity pathway analysis revealed the effects of treadmill training on autophagy, cAMP-mediated signaling, calcium signaling and NP signaling in dorsal horn nerves. Treadmill training reduced the expression of Akt3, Atf2, Gsk3b, Pik3c3, Ppp2ca, and Sqstm1, and increased the expression of Pik3cb in the autophagic pathway.

Conclusion

Our results suggest that treadmill training may alleviate nociceptive hyperalgesia in NP mice by modulating the autophagic pathway, providing unique mechanistic insights into the analgesic effects of exercise.

Exercise in the Prevention and Treatment of Type 2 Diabetes

Type 2 diabetes is a systemic, multifactorial disease that is a leading cause of morbidity and mortality globally. Despite a rise in the number of available medications and treatments available for management, exercise remains a first-line prevention and intervention strategy due to established safety, efficacy, and tolerability in the general population. Herein we review the predisposing risk factors for, prevention, pathophysiology, and treatment of type 2 diabetes. We emphasize key cellular and molecular adaptive processes that provide insight into our evolving understanding of how, when, and what types of exercise may improve glycemic control. © 2023 American Physiological Society. Compr Physiol 13:1-27, 2023.

Pain Fluctuations of Women with Subacute Herpetic Neuralgia During Local Methylcobalamin in Combination with Lidocaine Treatment: A Single-Blinded Randomized Controlled Trial

Purpose

To evaluate the efficacy and pain fluctuations of methylcobalamin in combination with lidocaine local injection treatment for subacute herpetic neuralgia (SHN).

Methods

Seventy-nine women (60.4 ± 2.7 years) with thoracic SHN were enrolled and randomized to receive a combination of methylcobalamin and lidocaine local injection (MI, N=40), or a combination of lidocaine patch 5% and oral methylcobalamin (PO, N=39) for four weeks. Repeated-measures analyses of variance were used to evaluate the effect on pain levels. Generalized estimation equations were used to analyze the cause-effect relationship between pain fluctuations and influencing factors.

Results

At the treatment endpoint, the group, treatment time, and group interacted with treatment time effects of the pain scores and area were statistically significant (P<0.001), The pain scores were 2.9 ±0.9 (MI) and 4.3 ± 1.5 (PO). 80.00% (MI) or 28.21% (PO) of patients had pain scores ≤ 3, the odds ratio was 2.84 (95% CI: 1.68 to 4.79). The incidence of postherpetic neuralgia was 5.0% (2/40) at 3 months. Pain fluctuated repeatedly during treatment. The pain fluctuation increased from 8.75 log folds in the afternoon, to 79.85 log folds at night. With the ADLs level increasing from 1 to 3, the pain fluctuated from 4.28 to 17.70 log folds. Allodynia, itching, sleep quality, and ADLs were the significant influencing factors (P<0.05).

Conclusion

This study validated the efficacy of methylcobalamin combined with lidocaine for SHN, and confirmed that pain levels in patients with SHN had an obvious circadian rhythm. ADLs were an important cause of pain fluctuations.

Common protein-coding variants influence the racing phenotype in galloping racehorse breeds

Selection for system-wide morphological, physiological, and metabolic adaptations has led to extreme athletic phenotypes among geographically diverse horse breeds. Here, we identify genes contributing to exercise adaptation in racehorses by applying genomics approaches for racing performance, an end-point athletic phenotype. Using an integrative genomics strategy to first combine population genomics results with skeletal muscle exercise and training transcriptomic data, followed by whole-genome resequencing of Asian horses, we identify protein-coding variants in genes of interest in galloping racehorse breeds (Arabian, Mongolian and Thoroughbred). A core set of genes, G6PC2, HDAC9, KTN1, MYLK2, NTM, SLC16A1 and SYNDIG1, with central roles in muscle, metabolism, and neurobiology, are key drivers of the racing phenotype. Although racing potential is a multifactorial trait, the genomic architecture shaping the common athletic phenotype in horse populations bred for racing provides evidence for the influence of protein-coding variants in fundamental exercise-relevant genes. Variation in these genes may therefore be exploited for genetic improvement of horse populations towards specific types of racing.

Effect of TGF-β1-Mediated Exercise Analgesia in Spared Nerve Injury Mice

Peripheral nerve injury leads to severe neuropathic pain. Previous studies have highlighted the beneficial effects of physical exercise on alleviating neuropathic pain. Exercise regulating transforming growth factor-β1 (TGF-β1) can improve several diseases and relieve neuropathic pain induced by peripheral nerve injury. Here, we investigated whether exercise could alleviate neuropathic pain by modulating TGF-β1 expression. We assessed mechanical and cold pain behavior and conducted molecular evaluation of the spinal cord. We found that spared nerve injury (SNI) led to mechanical and cold allodynia in the hind paw, elevated the expression of latency-associated peptide- (LAP-) TGF-β1, and activated astroglial in the spinal cord. Exercise decreases allodynia, astroglial activation, and LAP-TGF-β1 in SNI mice. Intrathecal injection of a TGF-type I receptor inhibitor attenuated exercise analgesia and enhanced astroglial activation. These findings demonstrate that exercise induces analgesia by promoting TGF-β1 activation and inhibiting astrogliosis. Our study reveals a new underlying mechanism for exercise-attenuated neuropathic pain in the maintenance stage of neuropathic pain after nerve injury.

Neuropathic-like Pain Symptoms and Their Association with Muscle Strength in Patients with Chronic Musculoskeletal Pain

The relationship between sarcopenia and pain remains unclear; thus, this study evaluated whether muscle strength is independently associated with neuropathic-like pain symptoms in patients with chronic musculoskeletal pain. A cut-off score of painDETECT ≥13 was used to indicate a possible neuropathic component. Handgrip strength was measured, and muscle mass was estimated. A total of 2599 patients, including 439 patients who reported neuropathic-like pain symptoms (16.9%), were included for analysis. Handgrip strength was significantly lower in patients experiencing neuropathic-like pain symptoms (23.23 ± 10.57 vs. 24.82 ± 10.43 kg, p < 0.001), and this result was chiefly found in female patients. However, there was no difference in estimated muscle mass. Shorter duration of pain, opioid usage, pain in lower limbs, sleep disturbance, and lower handgrip strength were significantly associated with neuropathic-like pain symptoms. In patients with handgrip strength below the reference values by sex, experiencing radiating pain and at least moderate sensory symptoms by light touch and thermal stimulation were more frequently reported. In conclusion, lower handgrip strength appeared to be an independent factor associated with symptoms suggestive of neuropathic pain in this population. Interventional studies are required to determine whether improvement in muscle strength can reduce the neuropathic pain component in chronic musculoskeletal pain.

Association of Dry Eye Diseases and Auditory Sensitivity

This study aimed to evaluate the association between dry eye and inner ear diseases in a Korean population. Methods: Data from the Korean National Health and Nutrition Survey (KNHANES V, 2010−2012), a national cross-sectional health examination and survey, were collected by the Korea Centers for Disease Control and Prevention. The association between dry eye and inner ear disease was determined using the chi-square test and logistic regression analysis. The individuals were divided into two age groups (<60 and ≥60 years). Results: In total, 17,542 individuals (n = 11,932 in the <60 years group and n = 5610 in the ≥60 years group) were enrolled. After adjusting for confounding factors, the logistic regression model revealed that the associated factors were dizziness and loss of balance experience (OR, 1.315; 95% CI, 1.143−1.513), self-awareness of abnormal voice (OR, 1.372; 95% CI, 1.120−1.679), subjective hearing discomfort (OR, 1.278; CI, 1.084−1.506), and tinnitus (OR, 1.265; 95% CI, 1.101−1.453). The inversely associated factor for dry eye was bilateral hearing loss (OR, 0.497; 95% CI, 0.367−0.672). The hearing threshold was lower in the dry eye group than in the non-dry eye group (p < 0.05). Conclusions: Tinnitus was associated with dry eye and bilateral hearing loss was inversely associated with dry eye. These results suggest that hypersensitivity of the senses and nerves, which is neuropathic hyperesthesia, is one of the main mechanisms of dry eye. Treatment of neuropathy may help in treating dry eye associated with dizziness or tinnitus.

The Effect of a Stretch and Strength-Based Yoga Exercise Program on Patients with Neuropathic Pain due to Lumbar Disc Herniation

STUDY DESIGN

Randomized controlled trial.

OBJECTIVE

To investigate the effect of a stretch and strengthbased yoga exercise program on neuropathic pain due to LDH.

SUMMARY OF BACKGROUND DATA

LDH with neuropathic pain influences treatment outcomes negatively. Most yoga poses include the parameters of spinal training and help reduce pain and disability in patients with low back injuries. We hypothesized that yoga positively affects both LDH and neuropathic pain by increasing mobilization, core muscle strength, and spinal and hamstring flexibility.

METHODS

In total, 48 patients with neuropathic pain due to LDH were randomly assigned to a control group and a yoga group. All patients underwent a patient education program. In addition, the selected yoga exercise was taught and performed to the yoga group for one hour twice weekly for 12 weeks. Neuropathic pain (Douleur Neuropathique 4 for diagnosis; Leeds Assessment of Neuropathic Symptoms and Signs for severity), low back pain (the short-form of McGill Pain Questionnaire), disability (Oswestry Disability Index), and function (modified Schober and passive knee extension test) were measured blind before and at the one-, three-, and six-month follow-ups. The patient global assessment was applied at the six-month followup. The intention-to-treat analysis was performed in this study.

RESULTS

The intention-to-treat analysis showed a statistically significant difference in neuropathic pain, patient global assess ment, low back pain, disability, and function in favor of the yoga group at post-treatment. The between-group effect sizes were moderate at six-months follow-up.

CONCLUSION

It was determined that the selected stretch and strength-based yoga exercise could be a promising treatment option for neuropathic pain due to LDH.

LEVEL OF EVIDENCE

2.

Aerobic Physical Exercise as a Non-medical Intervention for Brain Dysfunction: State of the Art and Beyond

Brain disorders, including stroke, Alzheimer's disease, depression, and chronic pain, are difficult to effectively treat. These major brain disorders have high incidence and mortality rates in the general population, and seriously affect not only the patient's quality of life, but also increases the burden of social medical care. Aerobic physical exercise is considered an effective adjuvant therapy for preventing and treating major brain disorders. Although the underlying regulatory mechanisms are still unknown, systemic processes may be involved. Here, this review aimed to reveal that aerobic physical exercise improved depression and several brain functions, including cognitive functions, and provided chronic pain relief. We concluded that aerobic physical exercise helps to maintain the regulatory mechanisms of brain homeostasis through anti-inflammatory mechanisms and enhanced synaptic plasticity and inhibition of hippocampal atrophy and neuronal apoptosis. In addition, we also discussed the cross-system mechanisms of aerobic exercise in regulating imbalances in brain function, such as the “bone-brain axis.” Furthermore, our findings provide a scientific basis for the clinical application of aerobic physical exercise in the fight against brain disorders.

Foot-ankle therapeutic exercise program can improve gait speed in people with diabetic neuropathy: a randomized controlled trial

This study sought to determine whether a foot–ankle therapeutic exercise program can improve daily physical activity (i.e. number of steps) and fast and self-selected gait speed in people with diabetic peripheral neuropathy (DPN). In this single-blind randomized controlled trial and intention-to-treat analysis, 78 volunteers with DPN were allocated into a control group, which received usual care, and an intervention group (IG), which received usual care plus a 12-week foot–ankle exercise program. The adherence at 12 weeks rate in the IG was 92.3% (36 participants) and the dropout was 5.1% in the control group (2 participants). The number of steps and self-selected gait speed did not change significantly in either group (p > 0.05), although a 1,365-step difference between groups were observed at 1-year followup. The 12-week foot–ankle therapeutic exercises improved significantly fast-gait speed (primary outcome) (p = 0.020), ankle range of motion (p = 0.048), and vibration perception (secondary outcomes) (p = 0.030), compared with usual-care at 12 weeks. At 24 weeks, the IG showed better quality of life than controls (p = 0.048). At 1-year, fast-gait speed and vibration perception remained higher in the IG versus controls. Overall, the program may be a complementary treatment strategy for improving musculoskeletal and functional deficits related to DPN.

Trial registration ClinicalTrials.gov NCT02790931 (06/06/2016).

The Neuropeptide α-Calcitonin Gene-Related Peptide as the Mediator of Beneficial Effects of Exercise in the Cardiovascular System

Regular physical activity exerts cardiovascular protective effects in healthy individuals and those with chronic cardiovascular diseases. Exercise is accompanied by an increased plasma concentration of α-calcitonin gene-related peptide (αCGRP), a 37-amino acid peptide with vasodilatory effects and causative roles in migraine. Moreover, mouse models revealed that loss of αCGRP disrupts physiological adaptation of the cardiovascular system to exercise in normotension and aggravates cardiovascular impairment in primary chronic hypertension, both can be reversed by αCGRP administration. This suggests that αCGRP agonists could be a therapeutic option to mediate the cardiovascular protective effects of exercise in clinical setting where exercise is not possible or contraindicated. Of note, FDA has recently approved αCGRP antagonists for migraine prophylaxis therapy, however, the cardiovascular safety of long-term anti-CGRP therapy in individuals with cardiovascular diseases has yet to be established. Current evidence from preclinical models suggests that chronic αCGRP antagonism may abolish the cardiovascular protective effects of exercise in both normotension and chronic hypertension.

Long Non-coding RNA and mRNA Expression Change in Spinal Dorsal Horn After Exercise in Neuropathic Pain Rats

Exercise can help inhibition of neuropathic pain (NP), but the related mechanism remains being explored. In this research, we performed the effect of swimming exercise on the chronic constriction injury (CCI) rats. Compared with CCI group, the mechanical withdrawal threshold of rats in the CCI-Swim group significantly increased on the 21st and 28th day after CCI surgery. Second-generation RNA-sequencing technology was employed to investigate the transcriptomes of spinal dorsal horns in the Sham, CCI, and CCI-Swim groups. On the 28th day post-operation, 306 intersecting long non-coding RNAs (lncRNAs) and 173 intersecting mRNAs were observed between the CCI vs Sham group and CCI-Swim vs CCI groups. Then, the biological functions of lncRNAs and mRNAs in the spinal dorsal horn of CCI rats were then analyzed. Taking the results together, this study could provide a novel perspective for the treatment for NP.

Voluntary exercise blocks ongoing pain and diminishes bone remodeling while sparing protective mechanical pain in a rat model of advanced osteoarthritis pain

ABSTRACT

Exercise is the most common treatment recommended by healthcare providers for the treatment of musculoskeletal pain. We examined whether voluntary running wheel exercise improves pain and bone remodeling in rats with monosodium iodoacetate-induced unilateral knee joint pain. During acquisition of wheel running before osteoarthritis (OA) treatment, rats separated into 2 groups characterized by either high or low levels of voluntary wheel running as indicated by distance and peak speed. After the induction of knee joint OA, all rats showed diminished voluntary wheel running throughout the study. Voluntary wheel running failed to alter evoked nociceptive responses evaluated as weight asymmetry or hind paw tactile thresholds at any timepoint of the study. By contrast, relief of ongoing pain was demonstrated by conditioned place preference produced by lidocaine injection into the monosodium iodoacetate-treated knee in high but not low-running rats. Both high and low voluntary runners showed diminished trabecular bone loss compared with sedentary controls. These observations indicate that both high-intensity and low-intensity exercise is beneficial in protecting against bone remodeling in advanced OA. The data suggest that similar to clinical observation, bone remodeling does not correlate with pain. In addition, these results suggest that higher intensity exercise may relieve persistent ongoing OA pain while maintaining movement-evoked nociception. The relief of ongoing pain can potentially offer significant improvement in quality of life, whereas preservation of responses to movement-evoked pain may be especially important in protecting the joint from damage because of overuse.

Mechanisms, Mediators, and Moderators of the Effects of Exercise on Chemotherapy-Induced Peripheral Neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is an adverse effect of neurotoxic antineoplastic agents commonly used to treat cancer. Patients with CIPN experience debilitating signs and symptoms, such as combinations of tingling, numbness, pain, and cramping in the hands and feet that inhibit their daily function. Among the limited prevention and treatment options for CIPN, exercise has emerged as a promising new intervention that has been investigated in approximately two dozen clinical trials to date. As additional studies test and suggest the efficacy of exercise in treating CIPN, it is becoming more critical to develop mechanistic understanding of the effects of exercise in order to tailor it to best treat CIPN symptoms and identify who will benefit most. To address the current lack of clarity around the effect of exercise on CIPN, we reviewed the key potential mechanisms (e.g., neurophysiological and psychosocial factors), mediators (e.g., anti-inflammatory cytokines, self-efficacy, and social support), and moderators (e.g., age, sex, body mass index, physical fitness, exercise dose, exercise adherence, and timing of exercise) that may illuminate the relationship between exercise and CIPN improvement. Our review is based on the studies that tested the use of exercise for patients with CIPN, patients with other types of neuropathies, and healthy adults. The discussion presented herein may be used to (1) guide oncologists in predicting which symptoms are best targeted by specific exercise programs, (2) enable clinicians to tailor exercise prescriptions to patients based on specific characteristics, and (3) inform future research and biomarkers on the relationship between exercise and CIPN.

Treatment for Diabetic Peripheral Neuropathy: What have we Learned from Animal Models?

INTRODUCTION

Animal models have been widely used to investigate the etiology and potential treatments for diabetic peripheral neuropathy. What we have learned from these studies and the extent to which this information has been adapted for the human condition will be the subject of this review article.

METHODS

A comprehensive search of the PubMed database was performed, and relevant articles on the topic were included in this review.

RESULTS

Extensive study of diabetic animal models has shown that the etiology of diabetic peripheral neuropathy is complex, with multiple mechanisms affecting neurons, Schwann cells, and the microvasculature, which contribute to the phenotypic nature of this most common complication of diabetes. Moreover, animal studies have demonstrated that the mechanisms related to peripheral neuropathy occurring in type 1 and type 2 diabetes are likely different, with hyperglycemia being the primary factor for neuropathology in type 1 diabetes, which contributes to a lesser extent in type 2 diabetes, whereas insulin resistance, hyperlipidemia, and other factors may have a greater role. Two of the earliest mechanisms described from animal studies as a cause for diabetic peripheral neuropathy were the activation of the aldose reductase pathway and increased non-enzymatic glycation. However, continuing research has identified numerous other potential factors that may contribute to diabetic peripheral neuropathy, including oxidative and inflammatory stress, dysregulation of protein kinase C and hexosamine pathways, and decreased neurotrophic support. In addition, recent studies have demonstrated that peripheral neuropathy-like symptoms are present in animal models, representing pre-diabetes in the absence of hyperglycemia.

CONCLUSION

This complexity complicates the successful treatment of diabetic peripheral neuropathy, and results in the poor outcome of translating successful treatments from animal studies to human clinical trials.

The role of exercise on peripheral nerve regeneration: from animal model to clinical application

Peripheral nerve injury is a complex condition with a variety of signs and symptoms depending on the severity and nerves involved. Peripheral nerve damage may lead to sensory and motor functions deficits and even lifelong disability, causing important socioeconomic costs worldwide. Despite the increase in knowledge of the mechanisms of injury and regeneration, a full functional recovery is still unsatisfying in the majority of patients. It is well known that exercise promotes physical and psychological well-being, by ameliorating general health. In the last years, there has been a growing interest in evaluating the effects of exercise on the peripheral nervous system. Experimental works with rodent models showed the potential utility of exercise following peripheral nerve injuries, as evinced by increasing axon regeneration, muscle reinnervation, better recovery of strength, muscle mass and higher expression of neurotrophic factors. Moreover, clinical evidence showed positive trends in favour of physical therapy following peripheral nerve damage based on the improvement of range of motion (ROM), muscle power grade and pain. After a brief overview of peripheral nerve anatomy and the different types of nerve injury, the present review aims to summarize the impact of exercise on peripheral nerve regeneration. Some clinical evidence regarding the effect of exercise after peripheral nerve injury will also be discussed.

Triptolide Attenuates Neuropathic Pain by Regulating Microglia Polarization through the CCL2/CCR2 Axis

Triptolide (T10) is a common anti-inflammatory and analgesic drug. However, the activation of microglia and elimination of the corresponding inflammatory response are new targets for the treatment of neuropathic pain. Chemokine CCL (CCL2) is a key mediator for activating microglia. In this study, the effects of triptolide on the activation and polarization of microglia cells and CCL2 and its corresponding receptor, chemokine receptor 2 (CCR2), were mainly discussed. Microglia were stimulated with 1 μg/mL lipopolysaccharide (LPS) and pretreated with 10, 20, and 40 nM T10 and CCR2 antagonist (RS102895), respectively. The quantitative polymerase chain reaction (QPCR) and western blot results showed that T10 could obviously inhibit the upregulation of CCL2 and CCR2 induced by LPS stimulation in microglia cells, inhibit the fluorescence intensity of glial fibrillary acidic protein (GFAP) and inducible nitric oxide synthase (iNOS) antibody immunostaining in cells, and upregulate the fluorescence intensity of arginase 1 antibody in cells. The expression of interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) was inhibited in a dose-dependent manner. RS102895 can significantly reverse the activation and M2 polarization of microglia pretreated with 40 nM T10 and weaken the anti-inflammatory effect of T10. The addition of CCL2 did not extremely affect the function of RS102895. T10 may inhibit microglia activation and M1 polarization by inhibiting the expression of CCL2 and CCR2, promoting M2 polarization, reducing the level of inflammatory factors in cells, and exerting its analgesic effect, which is worthy of clinical promotion as a drug for neuropathic pain.

Resistance training improves nerve conduction and arterial stiffness in older adults with diabetic distal symmetrical polyneuropathy: A randomized controlled trial

Diabetes is the main cause of peripheral neuropathy where older patients are at increased risk of diabetic distal symmetrical polyneuropathy (DSPN) due to age-related nerve degeneration and vascular changes. The aim of the study was to investigate the effect of resistance training on nerve conduction, measures of neuropathy and arterial stiffness in older patients with DSPN. In a randomized controlled trial, thirty-four older adults with type-2 diabetes and peripheral neuropathy were enrolled and randomly assigned to experimental and control groups. The experimental group carried out circuit resistance training (1-3 rounds, 11 exercises, 10-15 reps, 50%-60% of 1RM, 3 times per week) for 12 weeks. Measurements were performed at baseline and 48 h after the intervention. Measures of DSPN including Michigan neuropathy screening instrument (MNSI), Michigan diabetic neuropathy score (MDNS), motor nerve action potential amplitude (APA), sensory and motor nerve conduction velocity (NCV) improved following intervention (p < 0.001, p = 0.001, p = 0.034, p = 0.001, and p = 0.001, respectively). Sensory APA did not change after the intervention (p = 0.139). Cardio-ankle vascular index (CAVI) and ankle-brachial index (ABI) improved in the experimental group compared with the control group (p = 0.014 and p = 0.033, respectively). In addition, HbA1C decreased following the 12-week resistance training program (p = 0.002). Older adults with DSPN respond positively to resistance training by improved neuropathy symptoms, nerve conduction, arterial stiffness and glucose regulation. Resistance training offers a positive intervention that can abate the progression of DSPN in older adults.

Physical exercise mitigates neuropathic changes in an animal model for Charcot-Marie-Tooth disease 1X

Inherited neuropathies of the Charcot-Marie-Tooth (CMT) type 1 are still untreatable diseases of the peripheral nervous system. We have previously shown that macrophages substantially amplify neuropathic changes in various mouse models of CMT1 subforms and that targeting innate immune cells substantially ameliorates disease outcome. However, up to date, specific approaches targeting macrophages pharmacologically might entail side effects. Here, we investigate whether physical exercise dampens peripheral nerve inflammation in a model for an X-linked dominant form of CMT1 (CMT1X) and whether this improves neuropathological and clinical outcome subsequently. We found a moderate, but significant decline in the number of macrophages and an altered macrophage activation upon voluntary wheel running. These observations were accompanied by an improved clinical outcome and axonal preservation. Most interestingly, exercise restriction by ~40% accelerated amelioration of clinical outcome and further improved nerve structure by increasing myelin thickness compared to the unrestricted running group. This myelin-preserving effect of limited exercise was accompanied by an elevated expression of brain-derived neurotrophic factor (BDNF) in peripheral nerves, while the expression of other trophic factors like neuregulin-1, glial cell line-derived neurotrophic factor (GDNF) or insulin-like growth factor 1 (IGF-1) were not influenced by any mode of exercise. We demonstrate for the first time that exercise dampens inflammation and improves nerve structure in a mouse model for CMT1, likely leading to improved clinical outcome. Reducing the amount of exercise does not automatically decrease treatment efficacy, reflecting the need of optimally designed exercise studies to achieve safe and effective treatment options for CMT1 patients.

Exercise and Neuropathic Pain: A General Overview of Preclinical and Clinical Research

Neuropathic pain is a disease of the somatosensory system that is characterized by tingling, burning, and/or shooting pain. Medication is often the primary treatment, but it can be costly, thus there is an interest in understanding alternative low-cost treatments such as exercise. The following review includes an overview of the preclinical and clinical literature examining the influence of exercise on neuropathic pain. Preclinical studies support the hypothesis that exercise reduces hyperalgesia and allodynia in animal models of neuropathic pain. In human research, observational studies suggest that those who are more physically active have lower risk of developing neuropathic pain compared to those who are less active. Exercise studies suggest aerobic exercise training (e.g., 16 weeks); a combination of aerobic and resistance exercise training (e.g., 10–12 weeks); or high-intensity interval training (e.g., 15 weeks) reduces aspects of neuropathic pain such as worst pain over the past month, pain over the past 24 h, pain scores, or pain interference. However, not all measures of pain improve following exercise training (e.g., current pain, heat pain threshold). Potential mechanisms and future directions are also discussed to aid in the goal of understanding the role of exercise in the management of neuropathic pain. Future research using standardized methods to further understanding of the dose of exercise needed to manage neuropathic pain is warranted.

Wearable Focal Muscle Vibration on Pain, Balance, Mobility, and Sensation in Individuals with Diabetic Peripheral Neuropathy: A Pilot Study

People with diabetic peripheral neuropathy (DPN) experience a lower quality of life caused by associated pain, loss of sensation and mobility impairment. Current standard care for DPN is limited and lacking. This study explores the benefits of 4-week, in-home wearable focal muscle vibration (FMV) therapy on pain, balance, mobility, and sensation in people with DPN. Participants were randomized into three groups and received different FMV intensities. FMV was applied using a modified Myovolt^TM wearable device to the tibialis anterior, distal quadriceps, and gastrocnemius/soleus muscles on both lower limbs for three days a week over four weeks. The outcomes included pain, balance, mobility, sensation, device usage log, feedback survey, and a semi-structured interview. In all, 23 participants completed the study. The results showed significant improvement in average pain (Pre: 4.00 ± 2.29; Post: 3.18 ± 2.26; p = 0.007), pain interference with walking ability (Pre: 4.14 ± 3.20; Post: 3.09 ± 1.976; p = 0.03), and standard and cognitive Timed Up-and-Go scores (Pre: 13.75 ± 5.34; Post: 12.65 ± 5.25; p = 0.04; Pre: 15.12 ± 6.60; Post: 12.71 ± 5.57; p = 0.003, respectively); the overall pain improvement was trending towards significance (Pre: 3.48 ± 2.56; Post: 2.87 ± 1.85; p = 0.051). Balance and sensations improved but not significantly. There was a trend towards significance (p = 0.088), correlation (r = 0.382) between changes in balance and baseline pain. The participants were highly satisfied with wearable FMV and were 100% compliant. FMV therapy was associated with improved pain, mobility, and sensation. Further study with a larger sample and better outcome measures are warranted.

Chemotherapy-Induced Peripheral Neuropathy: Nursing Implications

Chemotherapy-induced peripheral neuropathy (CIPN) is an unsolved and potentially life-compromising problem for most patients receiving neurotoxic chemotherapy. It manifests with numbness, tingling, and possibly neuropathic pain and motor and autonomic symptoms. This review aims to provide an evidence synthesis that prepares nurses to comprehensively assess, provide supportive care for, and critically evaluate the literature on CIPN. The prevalence, significance, characteristics, mechanisms, and risk factors of CIPN will be discussed, as well as nursing-relevant evidence on the assessment, prevention, and management of CIPN. The importance of critical literature evaluation before clinical implementation to reduce physical and financial harms to patients will also be highlighted.

A Consideration of the Psychological Aspects to Managing Patients with Painful Diabetic Neuropathy: An Insight into Pain Management Services at a Tertiary Centre in the UK

Painful diabetic neuropathy (pDN) is characterised by both sensory and affective disturbances, suggesting a complex bidirectional relationship of neuropathic pain and mood disorders. Data on pDN indicate that neuropathic pain reduces quality of life, including mood and physical and social functioning. Depression and pain coping strategies such as catastrophising and social support predict pain severity. There is a significant and reciprocal relationship between depressed mood and increased pain. The key features of assessing people with neuropathic pain in relation to psychological aspects of their health are discussed in the context of management in a tertiary pain management centre (The Walton Centre, Liverpool, UK) including cognitive behavioural interventions amongst others to improve the quality of life in patients with pDN. We consider psychological issues as a factor influencing treatment and outcome in patients with pDN.

Metformin: A Prospective Alternative for the Treatment of Chronic Pain

Metformin (biguanide) is a drug widely used for the treatment of type 2 diabetes. This drug has been used for 60 years as a highly effective antihyperglycemic agent. The search for the mechanism of action of metformin has produced an enormous amount of research to explain its effects on gluconeogenesis, protein metabolism, fatty acid oxidation, oxidative stress, glucose uptake, autophagy and pain, among others. It was only up the end of the 1990s and beginning of this century that some of its mechanisms were revealed. Metformin induces its beneficial effects in diabetes through the activation of a master switch kinase named AMP-activated protein kinase (AMPK). Two upstream kinases account for the physiological activation of AMPK: liver kinase B1 and calcium/calmodulin-dependent protein kinase kinase 2. Once activated, AMPK inhibits the mechanistic target of rapamycin complex 1 (mTORC1), which in turn avoids the phosphorylation of p70 ribosomal protein S6 kinase 1 and phosphatidylinositol 3-kinase/protein kinase B signaling pathways and reduces cap-dependent translation initiation. Since metformin is a disease-modifying drug in type 2 diabetes, which reduces the mTORC1 signaling to induce its effects on neuronal plasticity, it was proposed that these mechanisms could also explain the antinociceptive effect of this drug in several models of chronic pain. These studies have highlighted the efficacy of this drug in chronic pain, such as that from neuropathy, insulin resistance, diabetic neuropathy, and fibromyalgia-type pain. Mounting evidence indicates that chronic pain may induce anxiety, depression and cognitive impairment in rodents and humans. Interestingly, metformin is able to reverse some of these consequences of pathological pain in rodents. The purpose of this review was to analyze the current evidence about the effects of metformin in chronic pain and three of its comorbidities (anxiety, depression and cognitive impairment).

Association Between Physical Activity Levels and Chemotherapy-Induced Peripheral Neuropathy Severity in Cancer Survivors

OBJECTIVES

To evaluate for differences in demographic and clinical characteristics, as well as subjective and objective measures of chemotherapy-induced peripheral neuropathy (CIPN), among different exercise groups.

SAMPLE & SETTING

Cancer survivors (N = 290) were recruited from throughout the San Francisco Bay Area.

METHODS & VARIABLES

Based on the recommended 150 minutes or more of exercise per week, survivors were classified into the no exercise (NoEx), less exercise (LessEx), or recommended exercise (RecEx) group. Survivors completed self-report questionnaires and underwent sensory and balance testing.

RESULTS

Compared to the RecEx group, survivors in the NoEx group had less education, were less likely to be married/partnered, had a lower household income, had a higher level of comorbidity, and had poorer functional status. No differences were found among the groups in CIPN duration; pain intensity scores; or changes in light touch, cold, and pain sensations.

IMPLICATIONS FOR NURSING

Clinicians can recommend walking as a therapeutic option for survivors with CIPN and refer them to physical therapy.

Characterization of blood-derived exosomal proteins after exercise

Objective

To assess changes in plasma exosome levels and protein content in mice after long-term exercise.

Methods

We subjected 9-month-old adult C57BL/6J mice to daily treadmill running exercise for 4 weeks prior to the isolation of blood-derived exosomes. Exosomal proteins were identified using mass spectrometry.

Results

Extracellular bodies were successfully isolated from mouse blood. Protein levels were altered in blood-derived exosomes after chronic treadmill exercise. Levels of the secretagogue secretogranin 2 were markedly elevated in exercise-induced exosomes.

Conclusion

Our data suggest that levels of secretogranin 2 were increased in mouse exosomes following chronic treadmill exercise. We conclude that exercise increases exocrine secretion of secretogranin 2.

Physiotherapy for people with painful peripheral neuropathies: a narrative review of its efficacy and safety

Pharmacological treatment for peripheral neuropathic pain has only modest effects and is often limited by serious adverse responses. Alternative treatment approaches including physiotherapy management have thus gained interest in the management of people with peripheral neuropathies. This narrative review summarises the current literature on the efficacy and safety of physiotherapy to reduce pain and disability in people with radicular pain and chemotherapy-induced peripheral neuropathy, 2 common peripheral neuropathies. For chemotherapy-induced peripheral neuropathy, the current evidence based on 8 randomised controlled trials suggests that exercise may reduce symptoms in patients with established neuropathy, but there is a lack of evidence for its preventative effect in patients who do not yet have symptoms. For radicular pain, most of the 21 trials investigated interventions targeted at improving motor control or reducing neural mechanosensitivity. The results were equivocal, with some indication that neural tissue management may show some benefits in reducing pain. Adverse events to physiotherapy seemed rare; however, these were not consistently reported across all studies. Although it is encouraging to see that the evidence base for physiotherapy in the treatment of peripheral neuropathic pain is growing steadily, the mixed quality of available studies currently prevents firm treatment recommendations. Based on promising preliminary data, suggestions are made on potential directions to move the field forward.

ASICs are required for immediate exercise-induced muscle pain and are downregulated in sensory neurons by exercise training

Exercise training is an effective therapy for many pain-related conditions, and trained athletes have lower pain perception compared with unconditioned people. Some painful conditions, including strenuous exercise, are associated with elevated levels of protons, metabolites, and inflammatory factors, which may activate receptors and/or ion channels, including acid-sensing ion channels (ASICs), on nociceptive sensory neurons. We hypothesized that ASICs are required for immediate exercise-induced muscle pain (IEIP) and that exercise training diminishes IEIP by modulating ASICs within muscle afferents. We found high-intensity interval training (HIIT) reduced IEIP in C57BL/6 mice and diminished ASIC mRNA levels in lumber dorsal root ganglia, and this downregulation of ASICs correlated with improved exercise capacity. Additionally, we found that ASIC3 -/- mice did not develop IEIP; however, the exercise capacity of ASIC3 -/- was similar to wild-type mice. These results suggest that ASICs are required for IEIP and that diminishment of IEIP after exercise training correlates with downregulation of ASICs in sensory neurons.NEW & NOTEWORTHY Exercise performance can be limited by the sensations of muscle fatigue and pain transmitted by muscle afferents. It has been proposed that exercise training abrogates these negative feedback signals. We found that acid-sensing ion channels (ASICs) are required for immediate exercise-induced muscle pain (IEIP). Moreover, exercise training prevented IEIP and was correlated with downregulation of ASICs in sensory neurons.

The Effects of Combined Exercise Training (Resistance-Aerobic) on Serum Kinesin and Physical Function in Type 2 Diabetes Patients with Diabetic Peripheral Neuropathy (Randomized Controlled Trials)

Diabetic peripheral neuropathy is one of the most common chronic complications of diabetics which causes nerve damage and muscle strength decrease in patients. This in turn results in imbalance leading to the diabetic patients' daily activity disparity. The present investigation was conducted to specifically study the effects of combined training (resistance-aerobic) on serum kinesin-1 and physical function in type 2 diabetes patients with diabetic peripheral neuropathy. 24 diabetic neuropathic females were randomly to be selected out and divided into two experimental and control groups. The experimental group received resistance-aerobic training for 3 sessions during eight weeks. The exercise training included resistance exercises with 2-3 sets, 6-7 exercise stations, 8-12 repetitions (reps), and 3-5 minutes of rest in between the exercises, and the aerobic exercises contained 50-65% of heart rate reserve (HRR) for 3 minutes with 30 seconds of rest interval between sets and 5-10 repetitions. Results show that the serum kinesin-1 level and aerobic endurance declined after eight weeks of combined (resistance-aerobic) exercise training, but this decrease was not significant. The upper body strength increased but it was not significant, while the lower body showed a significant strength increase. With regard to the progressive nature of diabetic peripheral neuropathy, it seems that even the little changes resulting from the combined exercise training can be useful. Nevertheless, more research is required in this area.

An Exploratory Randomized Trial of Physical Therapy for the Treatment of Chemotherapy-Induced Peripheral Neuropathy

Background. Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of taxane treatment and cannot currently be prevented or adequately treated. Physical therapy is often used for neural rehabilitation following injury but has not been evaluated in this patient population. Methods. Single-blind, randomized controlled exploratory study compared standard care to a physical therapy home program (4 visits) throughout adjuvant taxane chemotherapy for stage I-III patients with breast cancer (n = 48). Patient questionnaires and quantitative sensory testing evaluated the treatment effect throughout chemotherapy to 6 months post treatment. Nonrandomized subgroup analysis observed effect of general exercise on sensory preservation comparing those reporting moderate exercise throughout chemotherapy to those that did not exercise regularly. Clinical Trial Registration. clinicaltrials.gov (NCT02239601). Results. The treatment group showed strong trends toward less pain (odds ratio [OR] 0.41, 95% confidence interval [CI] 0.17-1.01; P = .053) and pain decreased over time (OR 0.85, 95% CI 0.76-0.94; P = .002). Pain pressure thresholds (P = .034) and grip dynamometry (P < .001) were improved in the treatment group. For the nonrandomized subgroup analysis, participants reporting general exercise had preservation of vibration (Left P = .001, Right P = .001) and normal heat pain thresholds (Left P = .021, Right P = .039) compared with more sedentary participants. Conclusion. Physical therapy home program may improve CIPN pain in the upper extremity for patients with breast cancer, and general exercise throughout chemotherapy treatment was observed to have correlated to preservation of sensory function. Further research is required to confirm the impact of a physical therapy home program on CIPN symptoms.

Exercise and Chronic Pain

In this chapter, we describe the impact and etiology of chronic pain, the associated changes in the nervous system, and the mechanisms by which exercise may be able to affect and reverse these changes. Evidence for efficacy of exercise in different conditions associated with chronic pain is presented, with focus on chronic low back pain, fibromyalgia, osteoarthritis, rheumatoid arthritis, and migraines. While the efficacy of exercise and level of evidence supporting it vary in different diseases, exercise has direct and indirect benefits for most patients suffering from chronic pain. Effective exercise regimens include education and cognitive restructuring to promote behavioral activation and reconceptualization of what pain means, with the goal of gradually reversing the vicious cycle of pain, inertia, sedentary behavior, and worsening disability. Long-term, consistent, individualized exercise-based treatment approaches are most likely to result in improvements in pain and function.

Hand and foot exercises for diabetic peripheral neuropathy: A randomized controlled trial

Exercises for diabetic peripheral neuropathy remain controversial, especially with regard to recommended precautions and weightbearing exercises for individuals. We aimed to investigate the effect of 8 weeks of simple hand, finger, and foot exercises in patients with diabetic peripheral neuropathy. After randomization, exercise (n = 51) and control (n = 53) groups received usual care and diabetic foot care education; only the exercise group performed exercises. Primary outcomes, including activities of daily living (assessed using the Patient Neurotoxicity Questionnaire), neuropathy severity (monofilament and vibration test), and pain (behavioral rating scale and Visual Analog Scale), and secondary outcomes, including physical function of the hand and foot (grip, pinch, finger counting time, and Timed Up and Go tests), were assessed at baseline, after the 8-week intervention, and at the 16-week follow-up. The exercise group showed significantly stronger improvements in motor score and specific activities of daily living, such as climbing stairs and performing work or chores. Our exercises can be used to improve limb function in patients with diabetic neuropathy.

Neuropathic pain after spinal cord injury and physical exercise in animal models: A systematic review and meta-analysis

The aim of this systematic review was to summarize the effects of physical exercise on neuropathic pain (NP) in animal models of SCI. The search was conducted in Medline and Science Direct to identify experimental preclinical studies involving animal models of SCI, physical exercise as an intervention and the assessment of NP. Fifteen articles met the eligibility criteria. The review shows that in studies of NP involving animal models of SCI, rodents are the most common species. Thoracic contusion is the most common injury and mechanical and thermal nociception are the most frequently assessed NP components. The benefits of physical exercise vary according to its starting period and total duration. In addition, there is considerable heterogeneity regarding the type and intensity of exercise capable of alleviating NP after SCI. Furthermore, physical exercise has beneficial effects on mechanical, thermal and cold nociception, and spontaneous pain. These results are weakened by the paucity of studies involving these pain outcomes. The review protocol is published for free access on the SyRF platform (http://syrf.org.uk/protocols/).

Neck pain in South Africa: An overview of the prevalence, assessment and management for the contemporary clinician

BACKGROUND

Neck pain is a prevalent condition and is associated with high levels of disability and pain. The long-term prognosis can be poor, and therefore effective management in the acute stage is important.

OBJECTIVES

To provide an overview of the prevalence of neck pain and physiotherapy management and to provide evidence-informed recommendations for clinical practice within a South African context.

METHOD

The literature was reviewed considering prevalence, risk factors and examination. Management recommendations were derived from the highest levels of evidence of clinical practice guidelines, systematic reviews and randomised clinical trials.

RESULTS

Neck pain is classified into four grades, and three trajectories of recovery have been identified. Although the incidence of neck pain globally is high, in the South African context the majority of the population have limited access to physiotherapy management. Sound clinical reasoning is important in the assessment and decision-making process for management. Exercise, and mobilisation or manipulation are effective treatment options in the management of most types of neck pain. Other physical modalities such as needling, transcutaneous electrical nerve stimulation, laser and intermittent traction may be used as an adjunct to management.

CONCLUSION

The burden of neck pain globally is high; however, there is a lack of information on current practice, prevalence and burden of neck pain in the South African context. Sound evidence-informed clinical reasoning to inform a working diagnosis and to enable patient-centred management is important.

CLINICAL IMPLICATIONS

A thorough assessment is essential to gather information to formulate hypotheses regarding diagnosis and prognosis for neck pain. Exercise, and mobilisation or manipulation are effective management options.

Neuropathic Pain in Taxane-Induced Peripheral Neuropathy: Evidence for Exercise in Treatment

One in 2 Canadians is expected to acquire cancer in their lifetime. Many cancers, including breast, ovarian, and lung cancer, are treated using taxane chemotherapy with curative intent. A major adverse effect with the use of taxane chemotherapeutic agents is taxane-induced peripheral neuropathy (TIPN). Both positive (spontaneous pain, heightened sensitivity with light touch, tingling, itching, burning) and negative (loss of touch, loss of hot/cold sensations, and loss of pain) sensory symptoms can be experienced in the hands and feet and worsen with increasing dose and treatment duration. The pathophysiology of TIPN is still unknown but likely involves multiple mechanisms, including microtubule impairment, neuroimmune and inflammatory changes, ion channel remodeling, impaired mitochondrial function, and genetic predisposition. This review highlights current theories on the pathophysiology for TIPN, the cellular responses thought to maintain neuropathic pain, and the growing support for exercise in the treatment and prevention of peripheral neuropathy and neuropathic pain in both animal and human models.

It's never too late - balance and endurance training improves functional performance, quality of life, and alleviates neuropathic symptoms in cancer survivors suffering from chemotherapy-induced peripheral neuropathy: results of a randomized controlled trial

Background

Chemotherapy-induced peripheral neuropathy (CIPN) can affect functional performance and quality of life considerably. Since balance training has proven to enhance physical function, it might be a promising strategy to manage CIPN-induced functional impairments.

Methods

Fifty cancer survivors with persisting CIPN after finishing their treatment were randomly allocated to an intervention (IG) or active control group (CG). The IG did endurance plus balance training, the CG only endurance training (twice weekly over 12 weeks). Pre- and post-assessments included functional performance, cardiorespiratory fitness, vibration sense, and self-reported CIPN symptoms (EORTC QLQ-CIPN20).

Results

Intention-to-treat analyses (n = 41) did not reveal a significant group difference (CG minus IG) for sway path in semi-tandem stance after intervention (primary endpoint), adjusted for baseline. However, our per-protocol analysis of 37 patients with training compliance ≥70% revealed: the IG reduced their sway path during semi-tandem stance (− 76 mm, 95% CI -141 – -17; CG: -6 mm, 95% CI -52 – 50), improved the duration standing on one leg on instable surface (11 s, 95% CI 8–17; CG: 0 s, 95%CI 0–5) and reported decreased motor symptoms (−8points, 95% CI -18 – 0; CG: -2points 95% CI -6 – 2). Both groups reported reduced overall- (IG: -10points, 95% CI -17 – -4; CG: -6points, 95% CI -11 – -1) and sensory symptoms (IG: -7points, 95% CI -15 – 0; CG: -7points, 95% CI -15 – 0), while only the CG exhibited objectively better vibration sense (knuckle: 0.8points, 95% CI 0.3–1.3; IG: 0.0points, 95% CI -1.1 – 0.9; patella: 1.0points, 95% CI 0.4–1.6: IG: -0.8points, 95% CI -0.2 – 0.0). Furthermore, maximum power output during cardiopulmonary exercise test increased in both groups (IG and CG: 0.1 W/kg, 95% CI 0.0–0.2), but only the CG improved their jump height (2 cm, 95% CI 0.5–3.5; IG: 1 cm, 95% CI -0.4 – 3.2).

Conclusion

We suppose that endurance training induced a reduction in sensory symptoms in both groups, while balance training additionally improved patients’ functional status. This additional functional effect might reflect the IG’s superiority in the CIPN20 motor score. Both exercises provide a clear and relevant benefit for patients with CIPN.

Trial registration

German Clinical Trials Register (DRKS) number: DRKS00005419, prospectively registered on November 19, 2013.

Association between musculoskeletal pain at multiple sites and objectively measured physical activity and work capacity: Results from UK Biobank study

OBJECTIVES

To describe the cross-sectional association between musculoskeletal pain at multiple sites and physical work capacity (PWC) and objectively measured physical activity (PA).

DESIGN

Observational study.

METHODS

Data from a subsample of the UK Biobank were utilised (n=9856; mean age 58.5 years, mean body mass index 30.2kg/m2, 62% female). PWC was measured by a bicycle ergometer and PA by an accelerometer. Pain experienced in hip, knee, back and neck/shoulder was collected by questionnaire. Linear regression modelling was used with adjustment for potential confounders to estimate the association between pain and PWC and PA.

RESULTS

Increase in number of painful sites was associated with lower PWC, moderate and vigorous PA and increased low intensity PA in a dose-response relationship (all p-values for trend ≤0.001) before and after adjustment for confounders. In site specific analyses, hip pain was associated with an increased low intensity PA (β 52.8min/week, 95% CI 2.3-103.2) and reduced moderate PA (β -50.1min/week, 95% CI -98.5 to -1.8). Knee pain was only associated with vigorous PA (β -5.7min/week, 95% CI -10.0 to -1.3). Pain at neck/shoulder pain and back were not independently associated with PWC and PA.

CONCLUSIONS

Greater number of painful sites is consistently associated with poorer PWC, increased low intensity PA and reduced moderate to vigorous PA. Clinicians should address the critical role of being physically active in managing chronic musculoskeletal pain and interventions targeting musculoskeletal pain may be needed to increase PA levels.