A Review of Spasticity Treatments: Pharmacological and Interventional Approaches

An optogenetic mouse model of hindlimb spasticity after spinal cord injury

Spasticity is a common comorbidity of spinal cord injury (SCI), disrupting motor function and resulting in significant discomfort. While elements of post-SCI spasticity can be assessed using pre-clinical SCI models, the robust measurement of spasticity severity can be difficult due to its periodic and spontaneous appearance. Electrical stimulation of sensory afferents can elicit spasticity-associated motor responses, such as spasms; however, placing surface electrodes on the hindlimbs of awake animals can induce stress or encumbrance that could influence the expression of behaviour. Therefore, we have generated a mouse model of SCI-related spasticity that utilizes optogenetics to activate a subset of cutaneous VGLUT2+ sensory afferents to produce reliable incidences of spasticity-associated responses in the hindlimb. To examine the efficacy of this optogenetic SCI spasticity model, a T9-T10 complete transection injury was performed in Islet1-Cre+/-;VGLUT2-Flp+/-;CreON-FlpON-CatCh+/- mice, followed by the implantation of EMG electrodes into the left and right gastrocnemius and tibialis anterior muscles. EMG recordings were performed during episodic optogenetic stimulation (1-2 sessions per week until 5 weeks post-injury (wpi); n = 10 females, 5 males). A subset of these mice (n = 3 females, 2 males) was also tested at 10 wpi. During each recording session, an optic fiber coupled to a 470 nm wavelength LED was used to deliver 9 × 100 ms light pulses to the palmar surface of each hind paw. The results of these recordings demonstrated significant increases in the amplitude of EMG responses to the light stimulus from 2 wpi to 10 wpi, suggesting increased excitability of cutaneous sensorimotor pathways. Interestingly, this effect was significantly greater in the female cohort than in the males. Incidences of prolonged involuntary muscle contraction in response to the stimulus (fictive spasms) were also detected through EMG and visual observation during the testing period, supporting the presence of spasticity. As such, the optogenetic mouse model developed for this study appears to elicit spasticity-associated behaviours in SCI mice reliably and may be valuable for studying SCI-related limb spasticity mechanisms and therapeutic.

Comparative effect of oral drugs in improving spasticity of different etiology: a network meta-analysis

INTRODUCTION

Spasticity, a prevalent manifestation of various neurological conditions, significantly impacts the quality of life of patients. Research on the effects of oral drugs on spasticity has produced controversial results. Thus, the aim of this network meta-analysis was to compare the efficacy of oral drugs for improving spasticity in patients with different etiologies.

METHODS

We searched four different databases from their inception to 30 November 2023. A network meta-analysis using a frequentist perspective was conducted to assess the effects of different oral drugs on spasticity, evaluated by the modified Ashworth scale.

RESULTS

Our findings showed that, in a frequentist network meta-analysis, eperisone, diazepam, and baclofen had significantly greater spasticity, as measured by the modified Ashworth scale, than did the placebo (MD: -0.80; 95% CIs: -1.42, -0.18; MD: -0.68; 95% CIs: -1.28, -0.09; MD: -0.58; 95% CIs: -1.11, -0.06, respectively).

CONCLUSION

In summary, our study confirmed that eperisone, diazepam, and baclofen could be effective approaches for reducing spasticity of different etiologies and could be useful approaches for improving patient quality of life. Key messages What is already known on this topic: The impact of oral drugs, such as baclofen, gabapentin, tizanidine, and dantrolene, in the treatment of spasticity has been documented. What this study adds: This study determines which of the oral drugs aimed at treating spasticity is the most effective across different etiologies. How this study might affect research, practice, or policy: This study suggests tailored treatment strategies for spasticity based on its etiology.

Mapping chromatin remodelling in glioblastoma identifies epigenetic regulation of key molecular pathways and novel druggable targets

BACKGROUND

Glioblastoma is the most common and aggressive malignant brain tumour in the adult population and its prognosis is dismal. The heterogeneous nature of the tumour, to which epigenetic dysregulation significantly contributes, is among the main therapeutic challenges of the disease.

RESULTS

We have leveraged SYNGN, an experimental pipeline enabling the syngeneic comparison of glioblastoma stem cells and expanded potential stem cell (EPSC)-derived neural stem cells to identify regulatory features driven by chromatin remodelling specifically in glioblastoma stem cells.

CONCLUSIONS

We show epigenetic regulation of the expression of genes and related signalling pathways contributing to glioblastoma development. We also identify novel epigenetically regulated druggable target genes on a patient-specific level, including SMOX and GABBR2.

Treatment Patterns and Healthcare Costs Among Patients with Stroke and Spasticity: A 2-Year Longitudinal Study

INTRODUCTION

Post-stroke spasticity (PSS) occurs in ~25-43% of patients between 2 weeks and 3 months following a stroke. This retrospective claims study examined the occurrence of spasticity, treatment patterns, healthcare resource utilization, and healthcare costs among patients who experienced a stroke over a 2-year period.

METHODS

Analyses were conducted using healthcare claims from the IQVIA PharMetrics Plus database of commercially/self-insured members from 2015 to 2021. Patients were selected based on two International Classification of Diseases, 10th revision diagnosis codes for stroke requiring an inpatient stay (index date) with continuous enrollment with medical/pharmacy benefits 12 months before (pre-index) and 24 months starting on the index date (post-index). PSS was defined by a diagnosis code for spastic hemiplegia or muscle contracture starting ≥ 7 days post-index, or claims indicating PSS treatment [botulinum toxin A (BoNT-A) or muscle relaxants] any time in the post-index period. A generalized linear model was developed to estimate cost ratios between patients with and without PSS.

RESULTS

Overall, 7851 patients fulfilled study criteria; 47.7% were treated with physical or occupational therapy, 11.3% with muscle relaxants, and 0.8% with BoNT-A; 12.4% met the post-index definition of PSS; 84.2% were identified using muscle relaxant or BoNT-A codes, 6.6% using diagnosis codes, and 9.2% using both. Median time to codes identifying PSS was 213 days. Patients treated with BoNT-A received an average of three treatments, starting 253 days (median) post-stroke. Mean all-cause healthcare costs were US$62,875 among patients with PSS versus $44,472 among patients without (P < 0.001), representing 39.6% higher adjusted all-cause healthcare costs among patients with PSS versus patients without PSS.

CONCLUSION

Patients with PSS utilized numerous treatment modalities and experienced higher mean all-cause healthcare costs than did those without PSS. Earlier identification to optimize treatment of PSS may represent an opportunity for cost savings within managed healthcare systems.

Targeting cryptic allosteric sites of G protein-coupled receptors as a novel strategy for biased drug discovery

G protein-coupled receptors (GPCRs) represent the largest family of membrane receptors and are highly effective targets for therapeutic drugs. GPCRs couple different downstream effectors, including G proteins (such as Gi/o, Gs, G12, and Gq) and β-arrestins (such as β-arrestin 1 and β-arrestin 2) to mediate diverse cellular and physiological responses. Biased signaling allows for the specific activation of certain pathways from the full range of receptors' signaling capabilities. Targeting more variable allosteric sites, which are spatially different from the highly conserved orthosteric sites, represents a novel approach in biased GPCR drug discovery, leading to innovative strategies for targeting GPCRs. Notably, the emergence of cryptic allosteric sites on GPCRs has expanded the repertoire of available drug targets and improved receptor subtype selectivity. Here, we conduct a summary of recent progress in the structural determination of cryptic allosteric sites on GPCRs and elucidate the biased signaling mechanisms induced by allosteric modulators. Additionally, we discuss means to identify cryptic allosteric sites and design biased allosteric modulators based on cryptic allosteric sites through structure-based drug design, which is an advanced pharmacotherapeutic approach for treating GPCR-associated diseases.

Comparative efficacy and acceptability of non-invasive neuromodulation technologies and botulinum toxin injections for post-stroke spasticity and motor function: a network meta-analysis of randomised controlled trials

Background

Non-invasive neuromodulation is a promising approach for improving spasticity and motor function after stroke. However, it is still unclear which type of non-invasive neuromodulation is effective and evidence of important differences between them and botulinum toxin (BoNT) injection is limited. We aimed to assess the comparative efficacy and acceptability of non-invasive neuromodulation technologies and BoNT for post-stroke spasticity and motor function.

Methods

In this network meta-analysis, Cochrane Library, EMBASE, MEDLINE, Web of Science, Scopus, CNKI, and Wan Fang Data were searched from the earliest records to 8 October 2024. Randomised controlled trials that compared any type of non-invasive neuromodulation therapies, BoNT, and control treatments (including sham or no stimulation/injection) for post-stroke spasticity measured by modified Ashworth scale (MAS) were included. MAS, motor function, and acceptability were pooled using random-effects model with summary weighted mean difference (WMD) or risk ratios (RR) alongside 95% confidence interval (CI). Ranking probabilities of the treatments were estimated. Clinical importance was categorized as definite, probable, possible, or definitely not, considering the relationship between effect measures (95% CI) and minimal clinically important difference (1, 6, and 1.5 points for MAS, motor function, and acceptability, respectively). The quality of evidence was assessed using CINeMA online web. PROSPERO registration CRD42024543494.

Findings

6260 studies were identified and 185 trials (11,185 participants; 12 interventions) were included. Compared with control treatments, BoNT, high- and low-frequency repetitive transcranial magnetic stimulation (HFrTMS and LFrTMS), and anodal, cathodal, and dual transcranial direct current stimulation (atDCS, ctDCS, and dtDCS) significantly improved spasticity at short-term follow-up (WMD range -0.81 to -0.31), but did not achieve clinical importance. At mid-term, ctDCS (WMD = -2.00; 95% CI: -3.03, -0.97) and dtDCS (WMD = -1.62; 95% CI: -3.22, -0.02) were more efficacious than control treatments in reducing post-stroke spasticity with probable clinical importance. For motor function, atDCS, ctDCS, and dtDCS were more efficacious than control treatments (WMD range 6.29-13.00), with probable clinical importance, while BoNT, HFrTMS, and LFrTMS with possible clinical importance (WMD range 3.42-5.28). Various modalities have comparable acceptability to control treatments (RR range 0.48-1.46). Confidence in accordance with CINeMA ranged from high to low. Sensitivity and meta-regression analyses on limb measured, cointervention, and stroke stage confirmed the main findings of this study.

Interpretation

Taken together with clinical importance, evidence available supports three forms of tDCS as effective treatments for post-stroke spasticity and/or motor impairments, whereas BoNT, HFrTMS, and LFrTMS for motor impairments. These modalities could be considered alongside rehabilitation interventions as core treatments for post-stroke spasticity and motor impairments.

Funding

China Postdoctoral Science Foundation (2024M752230).

Metabotropic GABAB Receptor Activation Induced by G Protein Coupling

G protein-coupled receptors (GPCRs) play central roles in regulating cellular responses through heterotrimeric G proteins (GP). Extensive studies have elucidated the complex cellular signaling mediated by GPCRs that accompany dynamic conformational changes upon activation. However, there has been less focus on the role of the GP on the activation process, particularly for class C GPCRs that function as obligate dimers. Herein, we report the pivotal role of GP coupling on the dynamic activation process for the metabotropic γ-aminobutyric acid receptor (GABABR) based on extensive atomistic simulations. We find that GP coupling triggers drastic conformational changes in the GABABR transmembrane domain (TMD), while an agonist alone is insufficient to shift the equilibrium state from the inactive to the active states. These conformational changes induced by GP coupling destabilize the inactive TM5/TM5 interface, shifting the equilibrium toward the activated TM6/TM6 interface. This active role of the GP in activation provides fresh insights into the activation mechanism of GABABR and perhaps other class C GPCRs. These insights should aid in the development of more potent and selective drugs.

Efficacy, Indications, and Safety of Intrathecal Baclofen Pump: A Narrative Review

PURPOSE OF REVIEW

Baclofen, a muscle relaxant that reduces the release of excitatory neurotransmitters in the pre-synaptic neurons stimulating inhibitory neuronal signals in post-synaptic neurons, has been around for over 5 decades. Baclofen is used primarily for spasticity and since 1982, has had a role as an intrathecal agent. In the present investigation, we review research trends and updates on safety and efficacy of intrathecal baclofen (ITB) pumps.

RECENT FINDINGS

Evaluation of safety and efficacy of ITB pumps in spasticity and relevant conditions was evaluated in the present investigation. PubMed and ClinicalTrials.gov were used to review appropriate related literature. Commonly reported aspects regarding ITB efficacy include comparison with alternative treatments, maintenance efficacy, and long-term outcomes. Safety considerations and risk factors associated with ITB include postoperative complications, withdrawal symptoms, tolerance issues, long-term management, and contraindications. In summary, the present investigation reveals that ITB is efficacious for muscle spasticity; however, efforts should be made to enhance safety and efficacy by providing improved best practice guidelines on maximum safe dose with the least amount of risk with individualized treatments.

The next frontier in multiple sclerosis therapies: Current advances and evolving targets

Recent advancements in research have significantly enhanced our comprehension of the intricate immune components that contribute to multiple sclerosis (MS) pathogenesis. By conducting an in-depth analysis of complex molecular interactions involved in the immunological cascade of the disease, researchers have successfully identified novel therapeutic targets, leading to the development of innovative therapies. Leveraging pioneering technologies in proteomics, genomics, and the assessment of environmental factors has expedited our understanding of the vulnerability and impact of these factors on the progression of MS. Furthermore, these advances have facilitated the detection of significant biomarkers for evaluating disease activity. By integrating these findings, researchers can design novel molecules to identify new targets, paving the way for improved treatments and enhanced patient care. Our review presents recent discoveries regarding the pathogenesis of MS, highlights their genetic implications, and proposes an insightful approach for engaging with newer therapeutic targets in effectively managing this debilitating condition.

Pharmacological management of secondary chronic spinal cord injury: a systematic review

INTRODUCTION

Spinal cord injury (SCI) may bring lifelong consequences for affected patients and a high financial burden to the health care system.

SOURCE OF DATA

Published peer-reviewed scientific articles identified from EMBASE, Google Scholar, PubMed and Scopus.

AREAS OF AGREEMENT

Surgery and blood pressure management are the main targets in acute SCI to avoid secondary damage.

AREAS OF CONTROVERSY

The management of secondary chronic SCI is challenging, with unpredictable outcomes.

GROWING POINTS

Given the lack of consensus on pharmacological therapy for acute and secondary chronic SCI, the present study analyses the currently available drugs and treatment options to manage secondary chronic SCI.

AREAS TIMELY FOR DEVELOPING RESEARCH

Different approaches exist for the pharmacological management of secondary chronic SCI. One of the most investigated drugs, 4-aminopyridine, improves central motor conduction and shows improvement in neurological signs. Positive results in different areas have been observed in patients receiving the anti-spastic drugs tizanidine and baclofen or Granulocyte colony-stimulating factor. Growth hormone showed only minimal or no significant effects, and the therapy of secondary chronic SCI with riluzole has been poorly researched to date.

Redox Homeostasis, Gut Microbiota, and Epigenetics in Neurodegenerative Diseases: A Systematic Review

Neurodegenerative diseases encompass a spectrum of disorders marked by the progressive degeneration of the structure and function of the nervous system. These conditions, including Parkinson's disease (PD), Alzheimer's disease (AD), Huntington's disease (HD), Amyotrophic lateral sclerosis (ALS), and Multiple sclerosis (MS), often lead to severe cognitive and motor deficits. A critical component of neurodegenerative disease pathologies is the imbalance between pro-oxidant and antioxidant mechanisms, culminating in oxidative stress. The brain's high oxygen consumption and lipid-rich environment make it particularly vulnerable to oxidative damage. Pro-oxidants such as reactive nitrogen species (RNS) and reactive oxygen species (ROS) are continuously generated during normal metabolism, counteracted by enzymatic and non-enzymatic antioxidant defenses. In neurodegenerative diseases, this balance is disrupted, leading to neuronal damage. This systematic review explores the roles of oxidative stress, gut microbiota, and epigenetic modifications in neurodegenerative diseases, aiming to elucidate the interplay between these factors and identify potential therapeutic strategies. We conducted a comprehensive search of articles published in 2024 across major databases, focusing on studies examining the relationships between redox homeostasis, gut microbiota, and epigenetic changes in neurodegeneration. A total of 161 studies were included, comprising clinical trials, observational studies, and experimental research. Our findings reveal that oxidative stress plays a central role in the pathogenesis of neurodegenerative diseases, with gut microbiota composition and epigenetic modifications significantly influencing redox balance. Specific bacterial taxa and epigenetic markers were identified as potential modulators of oxidative stress, suggesting novel avenues for therapeutic intervention. Moreover, recent evidence from human and animal studies supports the emerging concept of targeting redox homeostasis through microbiota and epigenetic therapies. Future research should focus on validating these targets in clinical settings and exploring the potential for personalized medicine strategies based on individual microbiota and epigenetic profiles.

AAPM&R consensus guidance on spasticity assessment and management

BACKGROUND

The American Academy of Physical Medicine and Rehabilitation (AAPM&R) conducted a comprehensive review in 2021 to identify opportunities for enhancing the care of adult and pediatric patients with spasticity. A technical expert panel (TEP) was convened to develop consensus-based practice recommendations aimed at addressing gaps in spasticity care.

OBJECTIVE

To develop consensus-based practice recommendations to identify and address gaps in spasticity care.

METHODS

The Spasticity TEP engaged in a 16-month virtual meeting process, focusing on formulating search terms, refining research questions, and conducting a structured evidence review. Evidence quality was assessed by the AAPM&R Evidence, Quality and Performance Committee (EQPC), and a modified Delphi process was employed to achieve consensus on recommendation statements and evidence grading. The Strength of Recommendation Taxonomy (SORT) guided the rating of individual studies and the strength of recommendations.

RESULTS

The TEP approved five recommendations for spasticity management and five best practices for assessment and management, with one recommendation unable to be graded due to evidence limitations. Best practices were defined as widely accepted components of care, while recommendations required structured evidence reviews and grading. The consensus guidance statement represents current best practices and evidence-based treatment options, intended for use by PM&R physicians caring for patients with spasticity.

CONCLUSION

This consensus guidance provides clinicians with practical recommendations for spasticity assessment and management based on the best available evidence and expert opinion. Clinical judgment should be exercised, and recommendations tailored to individual patient needs, preferences, and risk profiles. The accompanying table summarizes the best practice recommendations for spasticity assessment and management, reflecting principles with little controversy in care delivery.

Management of Medical Complications during the Rehabilitation of Moderate-Severe Traumatic Brain Injury

According to the Centers for Disease Control, in 2019, there were approximately 223,135 hospitalizations in the United States related to traumatic brain injury (TBI). If not managed properly, these patients can suffer complications with significant negative implications with respect to morbidity, mortality, and long-term functional prognosis. It is imperative that medical providers who care for patients with TBI across the entire spectrum of care readily diagnose and treat the sequela associated with moderate-severe brain trauma. This article will focus on some of the key medical issues that providers may encounter during acute inpatient rehabilitation.

Levator Labii Superioris Alaeque Nasi Targeted Botulinum Toxin Injection for Treatment of Perinasal Facial Discomfort and Snarling

Botulinum toxin has been increasingly studied and used for varying conditions, most notably, cosmetics. However, it has been shown that botulinum toxin demonstrates a high efficacy in treating spasticity disorders throughout the body, including the face. Facial spasms vary in pathophysiology, region, and severity. Some can be so severe that they can cause discomfort and emotional distress due to the involuntary facial expressions caused by the spasms. Most spasticity conditions are often treated with adjuvant therapy of oral muscle relaxants and analgesics depending on severity. However, these treatments impose risks of varying adverse effects from sedation, hypotension, and if chronic use, more severe effects such as central nervous system complications or QT prolongation. In addition, if spasms are localized, the muscle relaxant's mechanism is not targeted, leading to unnecessary systemic use. That being said, a more targeted and manageable treatment such as botulinum toxin presents itself as a potential option for patient's physical condition and everyday life quality. Our case presents a 62-year-old male, with a chronic history of localized, idiopathic spasms and discomfort within the Levator Labii Superioris Aqulae Nasi region. The patient had no history of previous neurological disorders, and imaging was unremarkable. The patient had been treated over the past 13 years with varying oral therapeutics including Cymbalta, Ibuprofen, and cyclobenzaprine with limited improvement, but presented to the clinic seeking a different treatment plan, as the adverse effects from the muscle relaxants were impeding his everyday activities. The patient was also experiencing significant pain and emotional stress due to the spasms. The risk and benefits of treatment options were discussed and the patient decided to move forward with botulinum injections. After the first injection, the patient reported his pain had significantly improved and was relieved to be off of chronic pain medications. Our case demonstrates, what increasing literature further also supports: botulinum toxin is becoming a potential effective treatment for a breadth of spasticity disorders with a more targeted mechanism, and more manageable treatment plan, while simultaneously improving the patient's quality of life.

Clinical outcome analysis of patients with multiple sclerosis - Analysis from the UK Medical Cannabis Registry

INTRODUCTION

Whilst disease-modifying therapies are the cornerstone for treatment of multiple sclerosis (MS), there is a need to develop novel therapeutics for the symptomatic sequalae of the disease. Cannabis-based medicinal products (CBMPs) have been suggested as a potential therapy for the associated pain, spasticity, and mental health disorders. However, there is a paucity of clinical evidence on CBMPs in MS. The aim of this study is to assess changes in MS-specific and general health-related quality of life (HRQoL) outcomes alongside adverse event incidence in patients prescribed CBMPs for MS from the UK Medical Cannabis Registry (UKMCR).

METHOD

Patients prescribed CBMPs for MS symptoms for longer than one month were identified from the UKMCR. The primary outcomes were changes from baseline in MS Quality of Life-54 (MSQoL-54), Generalised Anxiety Disorder-7 (GAD-7), Single-Item Sleep Quality Scale (SQS), and EQ-5D-5L scales at one month, three months and six months. p < 0.050 was defined as statistically significant.

RESULTS

141 patients met the inclusion criteria for the study. There was an improvement in the following subscales of the MSQoL-54 at 6 months: change in health scale, cognitive function, mental health composition, physical health, role limitations due to physical limitation and due to emotional problems, as well as social and sexual function (p < 0.050). There were also improvements in the EQ-5D-5L index value, GAD-7 and SQS (p < 0.050). 146 (103.55 %) adverse events were reported in total. Most were considered mild (n = 47; 33.33 %) and moderate (n = 72; 51.06 %).

CONCLUSIONS

This preliminary analysis demonstrates a possible association with improved general health-related quality of life in those prescribed CBMPs for MS. Moreover, the results suggest that CBMPs are well-tolerated in the first 6 months of treatment. However, this must be interpreted with caution considering the limitations of the observational study design.

Innovations in Stroke Recovery and Rehabilitation: Poststroke Pain

Pain can be a significant barrier to a stroke survivors' functional recovery and can also lead to a decreased quality of life. Common pain conditions after stroke include headache, musculoskeletal pain, spasticity-related pain, complex regional pain syndrome, and central poststroke pain. This review investigates the evidence of diagnostic and management guidelines for various pain syndromes after stroke and identifies opportunities for future research to advance the field of poststroke pain.

Mechanistic and therapeutic relationships of traumatic brain injury and γ-amino-butyric acid (GABA)

Traumatic brain injury (TBI) is a highly prevalent medical condition for which no medications specific for the prophylaxis or treatment of the condition as a whole exist. The spectrum of symptoms includes coma, headache, seizures, cognitive impairment, depression, and anxiety. Although it has been known for years that the inhibitory neurotransmitter γ-amino-butyric acid (GABA) is involved in TBI, no novel therapeutics based upon this mechanism have been introduced into clinical practice. We review the neuroanatomical, neurophysiological, neurochemical, and neuropharmacological relationships of GABA neurotransmission to TBI with a view toward new potential GABA-based medicines. The long-standing idea that excitatory and inhibitory (GABA and others) balances are disrupted by TBI is supported by the experimental data but has failed to invent novel methods of restoring this balance. The slow progress in advancing new treatments is due to the complexity of the disorder that encompasses multiple dynamically interacting biological processes including hemodynamic and metabolic systems, neurodegeneration and neurogenesis, major disruptions in neural networks and axons, frank brain lesions, and a multitude of symptoms that have differential neuronal and neurohormonal regulatory mechanisms. Although the current and ongoing clinical studies include GABAergic drugs, no novel GABA compounds are being explored. It is suggested that filling the gap in understanding the roles played by specific GABAA receptor configurations within specific neuronal circuits could help define new therapeutic approaches. Further research into the temporal and spatial delivery of GABA modulators should also be useful. Along with GABA modulation, research into the sequencing of GABA and non-GABA treatments will be needed.

Inhibitory kinesiotaping has no effect on post-stroke spasticity: Prospective, randomised, controlled study

OBJECTIVE

Motor neuron pool activity is high in spasticity. The effect of inhibitory kinesiotaping (KT) on spasticity is unclear. The aim of this study is to investigate the effect of inhibitory KT on spasticity after stroke.

METHODS

Fifty stroke patients with ankle plantarflexor spasticity were randomised to intervention (27) and control (23) groups. Inhibitory KT was applied to the triceps surae muscle in the intervention group and sham KT to the Achilles tendon in the control group. Inhibitory and sham KT were applied for 72 h with a combined conventional rehabilitation programme. Spasticity was assessed at baseline and 72 h after KT using three instruments: Modified Ashworth Scale (MAS), Homosynaptic Post-Activation Depression (HPAD) reflecting the level of motor neuron pool activity, and joint torque as a measure of resistance to passive ankle dorsiflexion.

RESULTS

The baseline MAS score, HPAD levels and dorsiflexion torque of the two groups were not significantly different. The change in MAS score was -3.7 ± 17.5 (p = 0.180) in the intervention group and 3.6 ± 33.3 (p = 0.655) in the control group. The change in dorsiflexion torque was -0.3 ± 16.1 kg m (p = 0.539) in the intervention group and 8.0 ± 24.1 kg m (p = 0.167) in the control group. The change in mean HPAD was 8.7 ± 34.7 (p = 0.911) in the intervention group and 10.1 ± 41.6 (p = 0.609) in the control group.

CONCLUSIONS

The present study showed that inhibitory KT has no antispastic effect in stroke patients.

Extracorporeal Shockwave Treatment as Additional Therapy in Patients with Post-Stroke Spasticity of Upper Limb-A Narrative Review

Stroke is a severe injury of the central nervous system (CNS) and one of the leading causes of long-term disability and mortality. One of the main symptoms of neurological diseases is spasticity. This is defined as a motor condition characterized by a velocity-dependent increase in tonic stretch reflexes with exaggerated tendon jerks and resulting in the hyperexcitability of the stretch reflex. Rehabilitation after a stroke is focused on relearning lost skills and regaining independence. Many new methods in neurorehabilitation have been introduced. This review concentrates on the current evidence for extracorporeal shockwave therapy (ESWT) as a noninvasive alternative to treat spasticity. We present the effect of EWST and radial EWST interventions to post-stroke patients with spasticity in the upper limb. Our collected data suggest that different parameters of shockwaves can be used to achieve functional improvementsin the upper limb after a stroke. Our accumulated data imply that ESWT is safe and can be used for pain relief, reduced muscle tension, and an increased range of motion. According to many studies, complications after shockwave treatment are infrequent. Transient complications after shockwave therapy (ESWT) include redness, tingling, pain, and bruising. We reviewed clinical trials that present the possible benefits in upper-limb function after shockwave therapy for post-stroke patients. In this article, we used many database search engines, including PEDro. In the stroke rehabilitation literature, a key methodological problem is the design of double-blind studies, which very often are not feasible.

Intrathecal baclofen for the management of hereditary spastic paraparesis: a systematic review

This systematic review aims to evaluate the use of intrathecal baclofen (ITB) for hereditary spastic paraparesis (HSP) treatment. An extensive search in two electronical databases was performed. We identified articles published between 1990 and 2022 (PubMed, Scopus), and applied the following inclusion criteria: diagnosis of HSP at the time of the intervention, either familial or sporadic; report on the effect of ITB in patients with HSP; test trial via either bolus injections or continuous infusion tests; and ITB pump implantation. A data extraction sheet based on the Cochrane Consumers and Communication Review Group's data extraction template was created and adapted to collect relevant data. A qualitative analysis was performed to present the results in narrative summary fashion. A total of 6 studies met our inclusion criteria. 51 patients with HSP had a pre-implantation ITB trial. The time since the diagnosis until the pump implantation ranged from 5 to 30 years. The initial bolus ranged from 20 to 50 μg and the mean doses used at steady state ranged from 65 to 705 μg. An improvement in spasticity was observed on the modified Ashworth Scale in patients treated with ITB. Although all studies reported a subjective gait improvement, not all found an objective improvement in gait. The most common side effect reported was catheter-related problems. The findings of this review support the use of ITB as an effective and a viable option for the treatment of spasticity in HSP refractory to conservative therapies.

Epidural Spinal Cord Stimulation for Spasticity: a Systematic Review of the Literature

OBJECTIVE

Spasticity is a form of muscle hypertonia secondary to various diseases, including traumatic brain injury, spinal cord injury, cerebral palsy, and multiple sclerosis. Medical treatments are available; however, these often result in insufficient clinical response. This review evaluates the role of epidural spinal cord stimulation (SCS) in the treatment of spasticity and associated functional outcomes.

METHODS

A systematic review of the literature was performed using the Embase, CENTRAL, and MEDLINE databases. We included studies that used epidural SCS to treat spasticity. Studies investigating functional electric stimulation, transcutaneous SCS, and animal models of spasticity were excluded. We also excluded studies that used SCS to treat other symptoms such as pain.

RESULTS

Thirty-four studies were included in the final analysis. The pooled rate of subjective improvement in spasticity was 78% (95% confidence interval, 64%-91%; I2 = 77%), 40% (95% confidence interval, 7%-73%; I2 = 88%) for increased H-reflex threshold or decreased Hoffman reflex/muscle response wave ratio, and 73% (65%-80%; I2 = 50%) for improved ambulation. Patients with spinal causes had better outcomes compared with patients with cerebral causes. Up to 10% of patients experienced complications including infections and hardware malfunction.

CONCLUSIONS

Our review of the literature suggests that SCS may be a safe and useful tool for the management of spasticity; however, there is significant heterogeneity among studies. The quality of studies is also low. Further studies are needed to fully evaluate the usefulness of this technology, including various stimulation paradigms across different causes of spasticity.

Intrathecal Baclofen Injection Efficacy for Spasticity Management in Patients With Stroke: A Meta-Analysis

Although intrathecal baclofen injections have been used for spasticity management regarding stroke, spinal cord injury, and central nervous system diseases, their relative efficacy is controversial. This systematic review scoured 3 multinational electronic databases (Cochrane Library, MEDLINE, and Embase) to isolate relevant studies. We analyzed non-randomized studies and randomized control trials (RCTs) with direct comparisons against other spasticity management interventions for adult stroke patients. Risk of Bias (RoB) and the Risk of Bias Assessment tool for Non-randomized Studies evaluations were implemented with Cochrane's RoB tool. Meta-analysis was performed with Revman 5.4, and evidence validity was assessed with the Grading of Recommendations, Assessment, Development, and Evaluations method. Lastly, the intrathecal baclofen injection meta-analysis included 2 RCTs and 7 non-RCTs for assessing spasticity and 4 non-RCTs to measure gait velocity. Based on this data, intrathecal baclofen injection significantly impacted spasticity and gait speed. Thus, intrathecal baclofen injection can potentially treat severe spasticity unresponsive to conventional spasticity therapy. Furthermore, clinicians must consider individual patient characteristics and conditions when contemplating intrathecal baclofen injection for spasticity intervention.

Effects of a full-body electrostimulation garment application in a cohort of subjects with cerebral palsy, multiple sclerosis, and stroke on upper motor neuron syndrome symptoms

OBJECTIVES

Dysfunction of the central nervous system may inflict spastic movement disorder (SMD). Electrical stimuli were identified as promising therapeutic option. Electrical stimulation provided by a 58-electrode full body garment was investigated based on data from regular trial fittings.

METHODS

Data from 72 testees were investigated. Age averages 36.6 (19.8) ys with 44 females. The cohort spans infantile cerebral paresis (CP) (n=29), multiple sclerosis (MS) (n=23) and stroke (n=20). Data were stratified by etiology and an entry BBS Score<45.

RESULTS

Effect sizes (Cohen`s d) related BBS, TUG, FGA, 10mWT, WMFT, EQ5D5L and Pain. Significance levels are indicated by *: p<0.05, **: p<0.01, ***: p<0.001, (t): p<0.1: CP: 1.64***, 0.29*, 1.59***, 0.76(t), 1.00***, 0.5*, 1.28***; MS: 1.83***, 0.83***, 1.28**, 1.07***, 0.93*, 1,11**, 0.78*; Stroke: 1.28**, 0.78**, 0.89, 0.92**, 0.71, 1.26*, 0.78*.

CONCLUSIONS

Multi-site transcutaneous electrical stimulation may increase ambulation related skills in subjects with SMD stemming from CP, MS and stroke. The results indicate effects on static and dynamic balance, fall risk, mobility, upper extremity improvement and an overall increase in health utility and a reduction in spasticity related pain. Effects are immediate as well as sustained. These results may inspire individual trial fittings and inform further controlled trials.

An isocratic RP-HPLC-UV method for simultaneous quantification of tizanidine and lidocaine: application to in vitro release studies of a subcutaneous implant

Implantable devices have been widely investigated to improve the treatment of multiple diseases. Even with low drug loadings, these devices can achieve effective delivery and increase patient compliance by minimizing potential side effects, consequently enhancing the quality of life of the patients. Moreover, multi-drug products are emerging in the pharmaceutical field, capable of treating more than one ailment concurrently. Therefore, a simple analytical method is essential for detecting and quantifying different analytes used in formulation development and evaluation. Here, we present, for the first time, an isocratic method for tizanidine hydrochloride (TZ) and lidocaine (LD) loaded into a subcutaneous implant, utilizing reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with a UV detector. These implants have the potential to treat muscular spasticity while providing pain relief for several days after implantation. Chromatographic separation of the two drugs was accomplished using a C18 column, with a mobile phase consisting of 0.1% TFA in water and MeOH in a 58 : 42 ratio, flowing at 0.7 ml min-1. The method exhibited specificity and robustness, providing accurate and precise results. It displayed linearity within the range of 0.79 to 100 μg ml-1, with an R2 value of 1 for the simultaneous analysis of TZ and LD. The developed method demonstrated selectivity, offering limits of detection and quantification of 0.16 and 0.49 μg ml-1 for TZ, and 0.30 and 0.93 μg ml-1 for LD, respectively. Furthermore, the solution containing both TZ and LD proved stable under various storage conditions. While this study applied the method to assess an implant device, it has broader applicability for analysing and quantifying the in vitro drug release of TZ and LD from diverse dosage forms in preclinical settings.

Cadaveric study of flexor digitorum profundus and superficialis and flexor pollicis longus innervation patterns for application in selective neurectomy

PURPOSE

Spasticity management in finger flexors (flexor digitorum profundus and superficialis and flexor pollicis longus) is a challenge. Recent studies demonstrated the short- and long-term efficacy of selective and hyperselective neurectomy for the spastic upper limb. However, hyperselective neurectomy of flexor digitorum profundus and flexor digitorum superficialis branches was incomplete, without impairing their muscular body and function. This cadaveric study describes a novel medial approach in the forearm, to reach all the muscular branches: flexor digitorum superficialis and profundus and flexor pollicis longus.

MATERIAL AND METHODS

Fourteen cadaveric fresh frozen upper limbs were used. The feasibility of the medial surgical approach was studied, as well as the number, length and point of emergence of the muscular branches from the median and ulnar nerves to the flexor pollicis longus, flexor digitorum profundus and flexor digitorum superficialis.

RESULTS

The medial approach to the forearm gave access to all the muscular branches from the median and ulnar nerves to the flexor pollicis longus, flexor digitorum superficialis and flexor digitorum profundus, in all cases. A Martin Gruber communicating branch was found in 7 cases out of 14.

CONCLUSION

The medial approach to the forearm gave access to all the muscular branches from the median and ulnar nerve to the flexor pollicis longus, flexor digitorum superficialis and flexor digitorum profundus, without extensive transmuscular dissection of the pronator teres or flexor digitorum superficialis muscles. This approach opens the way for selective neurectomy of the flexor pollicis longus, flexor digitorum profundus and flexor digitorum superficialis muscles.

LEVEL OF EVIDENCE

IV.

Lateral Pectoral Nerve Identification through Ultrasound-Guided Methylene Blue Injection during Selective Peripheral Neurectomy for Shoulder Spasticity: Proposal for a New Procedure

Internally rotated and adducted shoulder is a common posture in upper limb spasticity. Selective peripheral neurectomy is a useful and viable surgical technique to ameliorate spasticity, and the lateral pectoral nerve (LPN) could be a potential good target to manage shoulder spasticity presenting with internal rotation. However, there are some limitations related to this procedure, such as potential anatomical variability and the necessity of intraoperative surgical exploration to identify the target nerve requiring wide surgical incisions. This could result in higher post-surgical discomfort for the patient. Therefore, the aim of our study was to describe a modification of the traditional selective peripheral neurectomy procedure of the LPN through the perioperative ultrasound-guided marking of the target nerve with methylene blue. The details of the localization and marking procedure are described, as well as the surgical technique of peripheral selective neurectomy and the potential advantages in terms of nerve localization, surgical precision and patients' post-surgical discomfort. We suggest that the proposed modified procedure could be a valid technique to address some current limitations and move the surgical treatment of spasticity toward increasingly tailored management due to the ease of nerve identification, the possibility of handling potential anatomical variability and the resulting smaller surgical incisions.

Neuro-orthopaedic assessment and management in patients with prolonged disorders of consciousness: A review

BACKGROUND

Following a severe acquired brain injury, neuro-orthopaedic disorders are commonplace. While these disorders can impact patients' functional recovery and quality of life, little is known regarding the assessment, management and treatment of neuro-orthopaedic disorders in patients with disorders of consciousness (DoC).

OBJECTIVE

To describe neuro-orthopaedic disorders in the context of DoC and provide insights on their management and treatment.

METHODS

A review of the literature was conducted focusing on neuro-orthopaedic disorders in patients with prolonged DoC.

RESULTS

Few studies have investigated the prevalence of spastic paresis in patients with prolonged DoC, which is extremely high, as well as its correlation with pain. Pilot studies exploring the effects of pharmacological treatments and physical therapy show encouraging results yet have limited efficacy. Other neuro-orthopaedic disorders, such as heterotopic ossification, are still poorly investigated.

CONCLUSION

The literature of neuro-orthopaedic disorders in patients with prolonged DoC remains scarce, mainly focusing on spastic paresis. We recommend treating neuro-orthopaedic disorders in their early phases to prevent complications such as pain and improve patients' recovery. Additionally, this approach could enhance patients' ability to behaviourally demonstrate signs of consciousness, especially in the context of covert awareness.

Effect of transcutaneous spinal direct current stimulation on spasticity in upper motor neuron conditions: a systematic review and meta-analysis

STUDY DESIGN

A systematic review and meta-analysis of clinical trials.

OBJECTIVES

To determine the effect of non-invasive transcutaneous spinal direct current stimulation (tsDCS) on spasticity, activity limitations and participation restrictions in various upper motor neuron diseases.

METHODS

Six databases including CINAHL plus, Cochrane CENTRAL, Embase, MEDLINE, SCOPUS and Web of Science were searched for the relevant records from January 2008 to December 2022. Two reviewers independently selected and extracted data on spasticity, activity limitations and participation restrictions. The risk of bias was evaluated using the PEDro scale while the GRADE approach established the certainty of the evidence.

RESULTS

Eleven studies were identified of which 5 (45.5%) were rated as having a low risk of bias and 8 (72.7%) were meta-analyzed. The meta-analyses did not show any significant differences between cathodal (SMD = -0.67, 95% CI = -1.50 to 0.15, P = 0.11, I2 = 75%, 6 RCTs) or anodal (SMD = 0.11, 95% CI = -0.43 to -0.64, p = 0.69, I2 = 0%, 2 RCTs) and sham tsDCS for spasticity. There was also no significant difference between active and sham tsDCS for activity limitations (SMD = -0.42, 95% CI = -0.04 to 0.21, p = 0.2, I2 = 0%, 2 RCTs) and participation restrictions (MD = -8.10, 95% CI = -18.02 to 1.82, p = 0.11, 1 RCT).

CONCLUSIONS

The meta-analysis of the available evidence provides an uncertain estimate of the effect of cathodal tsDCS on spasticity, activity limitation and participation restriction. It might be very helpful, or it may make no difference at all. However, considering the level of the evidence and the limitation in the quality of the majority of the included studies, further well-designed research may likely change the estimate of effect.

TRIAL REGISTRATION

PROSPERO CRD42021245601.

Adults with Cerebral Palsy: Navigating the Complexities of Aging

The goal of this narrative review is to highlight the healthcare challenges faced by adults with cerebral palsy, including the management of long-term motor deficits, difficulty finding clinicians with expertise in these long-term impairments, and scarcity of rehabilitation options. Additionally, this narrative review seeks to examine potential methods for maintaining functional independence, promoting social integration, and community participation. Although the brain lesion that causes the movement disorder is non-progressive, the neurodevelopmental disorder worsens from secondary complications of existing sensory, motor, and cognitive impairments. Therefore, maintaining the continuum of care across one's lifespan is of utmost importance. Advancements in healthcare services over the past decade have resulted in lower mortality rates and increased the average life expectancy of people with cerebral palsy. However, once they transition from adolescence to adulthood, limited federal and community resources, and health care professionals' lack of expertise present significant obstacles to achieving quality healthcare and long-term benefits. This paper highlights the common impairments seen in adults with cerebral palsy. Additionally, it underscores the critical role of long-term healthcare and management to prevent functional decline and enhance quality of life across physical, cognitive, and social domains.

A UK Single-Center, Retrospective, Noninterventional Study of Clinical Outcomes and Costs of Two BotulinumtoxinA Treatments for Limb Spasticity

Service model changes at the North Staffordshire Rehabilitation Centre (UK) included switching spasticity treatment from onabotulinumtoxinA (onaBoNT-A) to abobotulinumtoxinA (aboBoNT-A). This noninterventional, retrospective, longitudinal study (NCT04396704) describes the clinical and economic outcomes in toxin-naive adults with spasticity who received onaBoNT-A (Cohort 1; 2015-2017) or aboBoNT-A (Cohort 2; 2017-2019). Outcomes included Goal Attainment Scale T (GAS-T) score, treatment satisfaction, quality of life (QoL; EQ-5D visual analog scale [VAS] score), and treatment costs. Adverse events were recorded for Cohort 2. Cohort 1 included 60 patients (mean [standard deviation] dose, 206.0 [98.8] U); Cohort 2 included 54 patients (753.7 [457.3] U). Mean (95% confidence interval) GAS-T scores for Cohorts 1 and 2 were 43.1 (39.3-46.9) and 47.8 (43.7-51.9) at Week 6, and 43.2 and 44.3 at Week 12, respectively. In both cohorts most patients were satisfied with treatment. At Week 12, QoL had not changed in Cohort 1 but had improved in Cohort 2 (EQ-5D VAS, -5). Mean estimated per-patient costs (in 2021) for Cohorts 1 and 2 were £315.56 and £249.25, respectively, at Week 6, and £343.20 and £273.21, respectively, at Week 12. Fifteen non-treatment-related serious adverse events and two deaths were recorded. These data may warrant a larger prospective study powered to compare outcomes of aboBoNT-A and onaBoNT-A.

Pain Management in the Most Vulnerable Intellectual Disability: A Review

This review is made up of two parts; the first part discussing intellectual disability (ID) in general, while the second part covers the pain associated with intellectual disability and the challenges and practical tips for the management of pain associated with (ID). Intellectual disability is characterized by deficits in general mental abilities, such as reasoning, problem solving, planning, abstract thinking, judgment, academic learning, and learning from experience. ID is a disorder with no definite cause but has multiple risk factors, including genetic, medical, and acquired. Vulnerable populations such as individuals with intellectual disability may experience more pain than the general population due to additional comorbidities and secondary conditions, or at least the same frequency of pain as in the general population. Pain in patients with ID remains largely unrecognized and untreated due to barriers to verbal and non-verbal communication. It is important to identify patients at risk to promptly prevent or minimize those risk factors. As pain is multifactorial, thus, a multimodal approach using both pharmacotherapy and non-pharmacological management is often the most beneficial. Parents and caregivers should be oriented to this disorder, given adequate training and education, and be actively involved with the treatment program. Significant work to create new pain assessment tools to improve pain practices for individuals with ID has taken place, including neuroimaging and electrophysiological studies. Recent advances in technology-based interventions such as virtual reality and artificial intelligence are rapidly growing to help give patients with ID promising results to develop pain coping skills with effective reduction of pain and anxiety. Therefore, this narrative review highlights the different aspects regarding the current status of the pain associated with intellectual disability, with more emphasis on the recent pieces of evidence for the assessment and management of pain among populations with intellectual disability.

Assessment of Health Care Costs and Total Baclofen Use Associated With Targeted Drug Delivery for Spasticity

BACKGROUND

Chronic spasticity causes significant impairment and financial burden. Oral baclofen, the first-line therapy, can have intolerable, dose-dependent side effects. Targeted drug delivery (TDD) through intrathecal baclofen delivers smaller amounts of baclofen into the thecal sac via an implanted infusion system. However, the health care resource utilization of patients with spasticity receiving TDD has not been studied extensively.

MATERIALS AND METHODS

Adult patients who received TDD for spasticity between 2009 and 2017 were identified using the IBM MarketScan® data bases. Patients' use of oral baclofen and health care costs were examined at baseline (one year before implantation) and three years after implantation. A multivariable regression model using the generalized estimating equations method and a log link function was used to compare postimplantation costs with those at baseline.

RESULTS

The study identified 771 patients with TDD for medication analysis and 576 for cost analysis. At baseline, the median costs were $39,326 (interquartile range [IQR]: $19,526-$80,679), which increased to $75,728 (IQR: $44,199-$122,676) in year 1, decreased to $27,160 (IQR: $11,896-$62,427) in year 2, and increased slightly to $28,008 (IQR: $11,771-$61,885) in year 3. In multivariable analysis, the cost was 47% higher than at baseline (cost ratio [CR] 1.47, 95% CI: 1.32-1.63) in year 1 but was 25% lower (CR 0.75, 95% CI: 0.66-0.86) in year 2 and 32% lower (CR 0.68, 95% CI: 0.59-0.79) in year 3. Before implant, 58% of patients took oral baclofen, which decreased to 24% by year 3. The median daily baclofen dose decreased from 61.8 mg (IQR: 40-86.4) before TDD to 32.8 mg (IQR: 30-65.7) three years later.

CONCLUSIONS

Our findings indicate that patients who undergo TDD use less oral baclofen, potentially reducing the risk of side effects. Although total health care costs increased immediately after TDD, most likely owing to device and implantation costs, they decreased below baseline after one year. The costs of TDD reach cost neutrality approximately three years after implant, indicating its potential for long-term cost savings.

Neuraxial drug delivery in pain management: An overview of past, present, and future

Activation of neuraxial nociceptive linkages leads to a high level of encoding of the message that is transmitted to the brain and that can initiate a pain state with its attendant emotive covariates. As we review here, the encoding of this message is subject to a profound regulation by pharmacological targeting of dorsal root ganglion and dorsal horn systems. Though first shown with the robust and selective modulation by spinal opiates, subsequent work has revealed the pharmacological and biological complexity of these neuraxial systems and points to several regulatory targets. Novel therapeutic delivery platforms, such as viral transfection, antisense and targeted neurotoxins, point to disease-modifying approaches that can selectively address the acute and chronic pain phenotype. Further developments are called for in delivery devices to enhance local distribution and to minimize concentration gradients, as frequently occurs with the poorly mixed intrathecal space. The field has advanced remarkably since the mid-1970s, but these advances must always address the issues of safety and tolerability of neuraxial therapy.

Effects of Therapist Intervention during Upper-Extremity Robotic Rehabilitation in Patients with Stroke

This study aimed to determine whether the treatment effect differs for patients with stroke who perform robot-assisted upper-extremity rehabilitation by themselves compared to those whose rehabilitation is actively assisted by a therapist. Stroke patients with hemiplegia were randomly divided into two groups and received robot-assisted upper-limb rehabilitation for four weeks. In the experimental group, a therapist actively intervened in the treatment, while in the control group, the therapist only observed. After four weeks of rehabilitation, the manual muscle strength, Brunnstrom stage, Fugl-Meyer assessment of the upper-extremity (FMA-UE), box and block test, and functional independence measure (FIM) showed significant improvement in both groups compared to that before treatment; however, no interval change in spasticity was noted. The post-treatment values showed that the FMA-UE and box and block tests were significantly improved in the experimental group compared to those in the control group. Comparing the changes in the pre- and post-treatment values, the FMA-UE, box and block test, and FIM of the experimental group were significantly improved compared to those in the control group. Our results suggest that active intervention by therapists during robot-assisted upper-limb rehabilitation positively impacts upper-extremity function outcomes in patients with stroke.

Post-activation depression from primary afferent depolarization (PAD) produces extensor H-reflex suppression following flexor afferent conditioning

Suppression of the extensor H-reflex by flexor afferent conditioning is thought to be produced by a long-lasting inhibition of extensor Ia afferent terminals via GABAA receptor-activated primary afferent depolarization (PAD). Given the recent finding that PAD does not produce presynaptic inhibition of Ia afferent terminals, we examined in 28 participants if H-reflex suppression is instead mediated by post-activation depression of the extensor Ia afferents triggered by PAD-evoked spikes and/or by a long-lasting inhibition of the extensor motoneurons. A brief conditioning vibration of the flexor tendon suppressed both the extensor soleus H-reflex and the tonic discharge of soleus motor units out to 150 ms following the vibration, suggesting that part of the H-reflex suppression during this period was mediated by postsynaptic inhibition of the extensor motoneurons. When activating the flexor afferents electrically to produce conditioning, the soleus H-reflex was also suppressed but only when a short-latency reflex was evoked in the soleus muscle by the conditioning input itself. In mice, a similar short-latency reflex was evoked when optogenetic or afferent activation of GABAergic (GAD2+ ) neurons produced a large enough PAD to evoke orthodromic spikes in the test Ia afferents, causing post-activation depression of subsequent monosynaptic EPSPs. The long duration of this post-activation depression and related H-reflex suppression (seconds) was similar to rate-dependent depression that is also due to post-activation depression. We conclude that extensor H-reflex inhibition by brief flexor afferent conditioning is produced by both post-activation depression of extensor Ia afferents and long-lasting inhibition of extensor motoneurons, rather than from PAD inhibiting Ia afferent terminals. KEY POINTS: Suppression of extensor H-reflexes by flexor afferent conditioning was thought to be mediated by GABAA receptor-mediated primary afferent depolarization (PAD) shunting action potentials in the Ia afferent terminal. In line with recent findings that PAD has a facilitatory role in Ia afferent conduction, we show here that when large enough, PAD can evoke orthodromic spikes that travel to the Ia afferent terminal to evoke EPSPs in the motoneuron. These PAD-evoked spikes also produce post-activation depression of Ia afferent terminals and may mediate the short- and long-lasting suppression of extensor H-reflexes in response to flexor afferent conditioning. Our findings highlight that we must re-examine how changes in the activation of GABAergic interneurons and PAD following nervous system injury or disease affects the regulation of Ia afferent transmission to spinal neurons and ultimately motor dysfunction in these disorders.

Efficacy of nabiximols oromucosal spray on spasticity in people with multiple sclerosis: Treatment effects on Spasticity Numeric Rating Scale, muscle spasm count, and spastic muscle tone in two randomized clinical trials

BACKGROUND

To provide a comprehensive assessment of the treatment effects of nabiximols oromucosal spray on multiple sclerosis spasticity in two clinical trials, GWSP0604 and SAVANT.

METHODS

Both studies enriched for responders before randomization, defined by a ≥20% improvement in Spasticity 0-10 numeric rating scale (NRS) score. Additionally, SAVANT used randomized re-titration following washout. Spasticity NRS outcomes, spasm count, and modified Ashworth scale (MAS) scores were analyzed.

RESULTS

Mean change from baseline in average daily Spasticity NRS scores was significantly larger for nabiximols than placebo at all postbaseline timepoints, ranging from -0.36 to -0.89 in GWSP0604 and -0.52 to -1.96 in SAVANT. Percent reduction in geometric mean change from baseline in average daily spasm count for nabiximols ranged from 19-35% versus placebo. A treatment difference favoring nabiximols was observed in overall MAS scores during the randomized part of each study. Treatment effect was larger for combinations of lower limb muscle groups (ranging between -0.16 and -0.37).

CONCLUSIONS

Nabiximols leads to improvement in spasticity that was sustained over the 12-week treatment period as measured by average daily Spasticity NRS scores, daily spasm counts, and MAS scores for combinations of muscle groups, especially the combination of the 6 key muscle groups in the lower limbs in NRS responders to nabiximols treatment.

Cannabis and Cannabinoids in Multiple Sclerosis: From Experimental Models to Clinical Practice-A Review

BACKGROUND

As far as 80% of people diagnosed with multiple sclerosis (MS) experience disabling symptoms in the course of the disease, such as spasticity and neuropathic pain. As first-line symptomatic therapy is associated with important adverse reactions, cannabinoids have become increasingly popular among patients with MS. This review intends to provide an overview of the evidence of the role of cannabinoids in treating symptoms related to MS and to encourage further research on this matter.

AREAS OF UNCERTAINTY

To date, the evidence supporting the role of cannabis and its derivatives in alleviating the MS-related symptoms comes only from studies on experimental models of demyelination. To the best of our knowledge, relatively few clinical trials inquired about the therapeutic effects of cannabinoids on patients with MS, with variable results.

DATA SOURCES

We conducted a literature search through PubMed and Google Scholar from the beginning until 2022. We included articles in English describing the latest findings regarding the endocannabinoid system, the pharmacology of cannabinoids, and their therapeutic purpose in MS.

RESULTS

Evidence from preclinical studies showed that cannabinoids can limit the demyelination process, promote remyelination, and have anti-inflammatory properties by reducing immune cell infiltration of the central nervous system in mice with experimental autoimmune encephalomyelitis. Moreover, it has been established that experimental autoimmune encephalomyelitis mice treated with cannabinoids experienced a significant reduction of symptoms and slowing of the disease progression. Given the complexity of human immune and nervous systems, cannabinoids did not have the anticipated effects on human subjects. However, data obtained from clinical trials showed some beneficial results of cannabinoids as a single or as add-on therapy in reducing the spasticity and pain related to MS.

CONCLUSION

Considering their various mechanisms of action and good tolerability, cannabinoids remain an interesting therapy for spasticity and chronic pain related to MS.

Discovery of Biomarkers for Amyotrophic Lateral Sclerosis from Human Cerebrospinal Fluid Using Mass-Spectrometry-Based Proteomics

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by the loss of upper and lower motor neurons, which eventually may lead to death. Critical to the mission of developing effective therapies for ALS is the discovery of biomarkers that can illuminate mechanisms of neurodegeneration and have diagnostic, prognostic, or pharmacodynamic value. Here, we merged unbiased discovery-based approaches and targeted quantitative comparative analyses to identify proteins that are altered in cerebrospinal fluid (CSF) from patients with ALS. Mass spectrometry (MS)-based proteomic approaches employing tandem mass tag (TMT) quantification methods from 40 CSF samples comprising 20 patients with ALS and 20 healthy control (HC) individuals identified 53 proteins that are differential between the two groups after CSF fractionation. Notably, these proteins included both previously identified ones, validating our approach, and novel ones that have the potential for expanding biomarker repertoire. The identified proteins were subsequently examined using parallel reaction monitoring (PRM) MS methods on 61 unfractionated CSF samples comprising 30 patients with ALS and 31 HC individuals. Fifteen proteins (APOB, APP, CAMK2A, CHI3L1, CHIT1, CLSTN3, ERAP2, FSTL4, GPNMB, JCHAIN, L1CAM, NPTX2, SERPINA1, SERPINA3, and UCHL1) showed significant differences between ALS and the control. Taken together, this study identified multiple novel proteins that are altered in ALS, providing the foundation for developing new biomarkers for ALS.

[Methods and results of neurosurgical treatment of cerebral palsy]

Treatment of spastic syndrome and muscular dystonia in patients with cerebral palsy is a complex clinical problem. Effectiveness of conservative treatment is not high enough. Modern neurosurgical techniques for spastic syndrome and dystonia are divided into destructive interventions and surgical neuromodulation. Their effectiveness is different and depends on the form of disease, severity of motor disorders and age of patients.

OBJECTIVE

To evaluate the effectiveness of various methods of neurosurgical treatment of spasticity and muscular dystonia in patients with cerebral palsy.

MATERIAL AND METHODS

We To evaluate the effectiveness of various methods of neurosurgical treatment of spasticity and muscular dystonia in patients with cerebral palsy.analyzed literature data in the PubMed database using the keywords «cerebral palsy», «spasticity», «dystonia», «selective dorsal rhizotomy», «selective neurotomy», «intrathecal baclofen therapy», «spinal cord stimulation», «deep brain stimulation».

RESULTS

Effectiveness of neurosurgery was higher for spastic forms of cerebral palsy compared to secondary muscular dystonia. Destructive procedures were the most effective among neurosurgical operations for spastic forms. Effectiveness of chronic intrathecal baclofen therapy decreases in follow-up due to secondary drug resistance. Destructive stereotaxic interventions and deep brain stimulation are used for secondary muscular dystonia. Effectiveness of these procedures is low.

CONCLUSION

Neurosurgical methods can partially reduce severity of motor disorders and expand the possibilities of rehabilitation in patients with cerebral palsy.

Intrathecal and Oral Baclofen Use in Adults With Spinal Cord Injury: A Systematic Review of Efficacy in Spasticity Reduction, Functional Changes, Dosing, and Adverse Events

OBJECTIVE

To examine the efficacy, dosing, and safety profiles of intrathecal and oral baclofen in treating spasticity after spinal cord injury (SCI).

DATA SOURCES

PubMed and Cochrane Databases were searched from 1970-2018 with keywords baclofen, spinal cord injury, and efficacy.

STUDY SELECTION

The database search yielded 588 sources and 10 additional relevant publications. After removal of duplicates, 398 publications were screened.

DATA EXTRACTION

Data were extracted using the following population, intervention, comparator, outcomes, and study designs criteria: studies including adult patients with SCI with spasticity; the intervention could be oral or intrathecal administration of baclofen; selection was inclusive for control groups, surgical management, rehabilitation, and alternative pharmaceutical agents; outcomes were efficacy, dosing, and adverse events. Randomized controlled trials, observational studies, and case reports were included. Meta-analyses and systematic reviews were excluded.

DATA SYNTHESIS

A total of 98 studies were included with 1943 patients. Only 4 randomized, double-blinded, and placebo-controlled trials were reported. Thirty-nine studies examined changes in the Modified Ashworth Scale (MAS; 34 studies) and Penn Spasm scores (Penn Spasm Frequency; 19 studies), with average reductions of 1.7±1.3 and 1.6±1.4 in individuals with SCI, respectively. Of these data, a total of 6 of the 34 studies (MAS) and 2 of the 19 studies (Penn Spasm Frequency) analyzed oral baclofen. Forty-three studies addressed adverse events with muscle weakness and fatigue frequently reported.

CONCLUSIONS

Baclofen is the most commonly-prescribed antispasmodic after SCI. Surprisingly, there remains a significant lack of large, placebo-controlled, double-blinded clinical trials, with most efficacy data arising from small studies examining treatment across different etiologies. In the studies reviewed, baclofen effectively improved spasticity outcome measures, with increased efficacy through intrathecal administration. Few studies assessed how reduced neural excitability affected residual motor function and activities of daily living. A host of adverse events were reported that may negatively affect quality of life. Comparative randomized controlled trials of baclofen and alternative treatments are warranted because these have demonstrated promise in relieving spasticity with reduced adverse events and without negatively affecting residual motor function.

Ionic Plasticity: Common Mechanistic Underpinnings of Pathology in Spinal Cord Injury and the Brain

The neurotransmitter GABA is normally characterized as having an inhibitory effect on neural activity in the adult central nervous system (CNS), which quells over-excitation and limits neural plasticity. Spinal cord injury (SCI) can bring about a modification that weakens the inhibitory effect of GABA in the central gray caudal to injury. This change is linked to the downregulation of the potassium/chloride cotransporter (KCC2) and the consequent rise in intracellular Cl- in the postsynaptic neuron. As the intracellular concentration increases, the inward flow of Cl- through an ionotropic GABA-A receptor is reduced, which decreases its hyperpolarizing (inhibitory) effect, a modulatory effect known as ionic plasticity. The loss of GABA-dependent inhibition enables a state of over-excitation within the spinal cord that fosters aberrant motor activity (spasticity) and chronic pain. A downregulation of KCC2 also contributes to the development of a number of brain-dependent pathologies linked to states of neural over-excitation, including epilepsy, addiction, and developmental disorders, along with other diseases such as hypertension, asthma, and irritable bowel syndrome. Pharmacological treatments that target ionic plasticity have been shown to bring therapeutic benefits.

Assessment of 30-Day Adverse Events in Single-Event, Multilevel Upper Extremity Surgery in Adult Patients with Upper Motor Neuron Syndrome

BACKGROUND

Upper motor neuron (UMN) syndrome consists of muscle spasticity, weakness, and dyssynergy due to a brain or spinal cord injury. The purpose of this study is to describe the perioperative adverse events for adult patients undergoing single-event, multilevel upper extremity surgery (SEMLS) due to UMN syndrome.

METHODS

A retrospective case series was performed for 12 consecutive adult patients who underwent SEMLS to correct upper extremity dysfunction or deformity secondary to UMN syndrome. The evaluation consisted of primary outcome measures to identify readmission rates and classify adverse events that occurred within 30 days after surgery.

RESULTS

All 12 patients were functionally dependent with 50% (n = 6) men and 50% (n = 6) women at a mean age of 43.6 years (range: 21-73) with a mean of 5.92 (range: 0-16) comorbid diagnoses at the time of surgery. There were no intraoperative complications, hospital readmissions, or deaths among the 12 patients. Five patients experienced 5 minor postoperative complications that consisted of cast- or orthosis-related skin breakdown remote from the incision (n = 3), incidental surgical site hematoma that required no surveillance or intervention (n = 1), and contact dermatitis attributed to the surgical dressing that resolved with topical corticosteroids (n = 1).

CONCLUSIONS

With an appropriate multidisciplinary approach, there is minimal risk for developing perioperative and 30-day postoperative adverse events for adults undergoing SEMLS to correct upper extremity deformities secondary to UMN syndrome.

LEVEL OF EVIDENCE

Level IV.

After 55 Years of Neurorehabilitation, What Is the Plan?

Neurological disorders often cause severe long-term disabilities with substantial activity limitations and participation restrictions such as community integration, family functioning, employment, social interaction and participation. Increasing understanding of brain functioning has opened new perspectives for more integrative interventions, boosting the intrinsic central nervous system neuroplastic capabilities in order to achieve efficient behavioral restitution. Neurorehabilitation must take into account the many aspects of the individual through a comprehensive analysis of actual and potential cognitive, behavioral, emotional and physical skills, while increasing awareness and understanding of the new self of the person being dealt with. The exclusive adoption by the rehabilitator of objective functional measures often overlooks the values and goals of the disabled person. Indeed, each individual has their own rhythm, unique life history and personality construct. In this challenging context, it is essential to deepen the assessment through subjective measures, which more adequately reflect the patient’s perspective in order to shape genuinely tailored instead of standardized neurorehabilitation approaches. In this overly complex panorama, where confounding and prognostic factors also strongly influence potential functional recovery, the healthcare community needs to rethink neurorehabilitation formats.

A Practical Post-Stroke Elbow Spasticity Assessment Using an Upper Limb Rehabilitation Robot: A Validation Study

Spasticity is a motor disorder characterised by a velocity-dependent increase in muscle tone, which is critical in neurorehabilitation given its high prevalence and potential negative influence among the post-stroke population. Accurate measurement of spasticity is important as it guides the strategy of spasticity treatment and evaluates the effectiveness of spasticity management. However, spasticity is commonly measured using clinical scales which may lack objectivity and reliability. Although many technology-assisted measures have been developed, showing their potential as accurate and reliable alternatives to standard clinical scales, they have not been widely adopted in clinical practice due to their low usability and feasibility. This paper thus introduces an easy-to-use robotic based measure of elbow spasticity and its evaluation protocol. Preliminary results collected with one post-stroke patient and one healthy control subject are presented and demonstrate the feasibility of the approach.

Effects of Peripheral Electromagnetic Fields on Spasticity: A Systematic Review

Electromagnetic fields are emerging as a therapeutic option for patients with spasticity. They have been applied at brain or peripheral level. The effects of electromagnetic fields applied to the brain have been extensively studied for years in spasticity, but not so at the peripheral level. Therefore, the purpose of our work is to analyze the effects of electromagnetic fields, applied peripherally to spasticity. A systematic review was conducted resulting in 10 clinical trials. The frequency ranged from 1 Hz to 150 Hz, with 25 Hz being the most commonly used and the intensity it was gradually increased but there was low homogeneity in how it was increased. Positive results on spasticity were found in 80% of the studies: improvements in stretch reflex threshold, self questionnaire about difficulties related to spasticity, clinical spasticity score, performance scale, Ashworth scale, spastic tone, Hmax/Mmax Ratio and active and passive dorsal flexion. However, results must be taken with caution due to the large heterogeneity and the small number of articles. In future studies, it would be interesting to agree on the parameters to be used, as well as the way of assessing spasticity, to be more objective in the study of their effectiveness.

Digital Health Technologies in Pediatric Trials

BACKGROUND

Advances in the miniaturization of sensors and other technologies provide opportunities to collect physiological and/or functional data directly from patients participating in clinical trials. The use of such technologies in children is particularly promising. Objective, quantifiable measurements made by these technologies, often on a continuous or frequent basis, may provide more robust data than the episodic reports from caregivers that are used in traditional pediatric trials.

METHODS

We reviewed the pros and cons of these technologies for use in a variety of pediatric diseases, including seizure and neuromuscular disorders, cardiorespiratory diseases, and metabolic disorders.

RESULTS

Correlation between sensor measurements and patient observations or traditional clinical measurements varied depending on the disease being evaluated. There was a notable dearth of reports on the use of digital health technology in pediatric patients. Given the range of sensors and measurements that can be made by DHTs, selection of the design, metrics and types of sensors best suited to disease evaluation presents challenges for adoption of these technologies in clinical trials.

CONCLUSION

Traditional measurements of drug effects are often deficient, particularly in the evaluation of infants and young children. The opportunity to make objective, frequent measurements may increase our power to detect and quantify responses to therapy in these populations. Further research and evaluation are needed to realize the full scientific potential of remote monitoring in pediatric clinical trials.

When Two Is Better Than One: A Pilot Study on Transcranial Magnetic Stimulation Plus Muscle Vibration in Treating Chronic Pelvic Pain in Women

Chronic pelvic pain syndrome (CPPS) affects about 4–16% of adult women, and about one-third of them require medical assistance due to severe symptoms. Repetitive transcranial magnetic stimulation (rTMS) over the supplementary motor area (SMA) has been shown to manage pain in refractory CPPS. Focal muscle vibration (FMV) has also been reported to relieve pelvic pain. The objective of this study was to assess the feasibility and effect of rTMS coupled with FMV to reduce pain in seven adult women with refractory CPPS. This pilot, open-labeled, prospective trial examined treatment by 5 Hz rTMS over SMA and 150 Hz FMV over the perineum, suprapubic, and sacrococcygeal areas, with one daily session for five consecutive days for three weeks. We assessed tolerance and subjective pain changes (as per visual analog scale, VAS) until one month post-treatment, with a primary endpoint at day 7. No patients experienced serious adverse effects or a significant increase in pain. Six out of seven patients experienced a VAS improvement of at least 10% at T7; three of these individuals experienced a VAS improvement of more than 30%. Overall, we found a significant VAS reduction of 15 points (95% CI 8.4–21.6) at T7 (t = 6.3, p = 0.001; ES = 2.3 (1.1–3.9)). Three of the women who demonstrated a significant VAS reduction at T7 retained such VAS improvement at T30. VAS decreased by six points (95% CI 1.3–10.7) at T30 (t = 3.1, p = 0.02; ES = 1.5 (0.2–2.6)). This coupled approach seems promising for pain management in adult women with refractory CPPS and paves the way for future randomized controlled trials.

Evaluating the use of baclofen as adjunct treatment for muscle tension dysphonia

OBJECTIVE

To explore whether use of baclofen as adjunct treatment to voice therapy (VT) led to improvement in subjective throat symptoms in patients with primary muscle tension dysphonia (MTD). MTD is associated with excessive paralaryngeal muscle contraction, and baclofen is a muscle relaxant.

STUDY DESIGN

Cross-sectional, questionnaire-based study.

METHODS

An initial pool of patients, who were diagnosed with primary MTD and received 1+ VT session(s) at a single tertiary-care center from 2015 to 2019, were placed into either a baclofen group (prescribed 10 mg baclofen t.i.d. PRN along with VT) based on symptomatology or non-baclofen group (VT alone). They were administered questionnaires via postage mail or phone that included the Voice Handicap Index-10 (VHI-10), Reflux Symptom Index (RSI), and other survey elements. A retrospective chart review collected demographic and other clinical data from recruited participants.

RESULTS

A total of 314 non-baclofen and 63 baclofen patients met the inclusion criteria of this study, with 37 non-baclofen patients (mean age = 47.5 years, 62.2% female) and 15 baclofen patients (mean age = 45.5 years, 73.3% female) recruited. There was no significant difference in mean [SD] VHI-10 scores (11.30 [8.20] vs. 12.60 [10.75]; p = 0.638) and RSI scores (13.46 [10.44] vs. 16.20 [10.65]; p = 0.398) between non-baclofen and baclofen groups, respectively.

CONCLUSION

There was no significant difference in voice psychometric outcomes between non-baclofen and baclofen groups, measured primarily by the VHI-10 and RSI questionnaire components. Further studies are warranted to assess the efficacy and safety of baclofen as a therapeutic option for MTD.

Multiple sclerosis by phenotype in Germany

BACKGROUND

A diagnosis of multiple sclerosis (MS) can be categorized based on its disease course into the following phenotypes: relapsing-remitting MS (RRMS), primary progressive MS (PPMS), and secondary progressive MS (SPMS). With one exception, studies of MS by phenotype either provide only prevalence data or if describing drug utilization, the emphasis is on patients with RRMS; while drug utilization by phenotype tends to be examined over the course of a year. No recent studies have comprehensively evaluated MS phenotypes by prevalence, drug utilization, and comorbidities over time from a population-based perspective, which is essential for understanding the disease burden and identifying unmet needs in MS. Germany is one of the few countries where specific MS phenotypes are commonly recorded in routine clinical practice. The purpose of this study was to compare MS phenotypes with respect to changes in their population-based prevalence rates and the types of MS treatments prescribed over time, as well as the frequency of clinical conditions associated with MS based on data from a German health insurance database.

METHODS

This retrospective, observational, cohort study used data from a German health insurance database for the period 2010 to 2017. Patients aged 18+ years with a specified phenotype of MS based on ICD-10 diagnosis coding were included in the analysis.

RESULTS

In 2010, RRMS was reported in 73%, PPMS in 8%, and SPMS in 19% of patients with MS with a known phenotype. The mean ages of patients were 41.4, 53.6, and 52.8 years, respectively, and all phenotypes were associated with a female predominance (69%, 63% and 63%, respectively). The prevalence rate of each phenotype markedly increased during the study period (RRMS +113%, PPMS +40%, SPMS +54%; in 2017 the rates were 183, 14, and 34 per 100,000, respectively). The mean age of patients reporting each phenotype also increased (p<0.01), while the female:male proportion remained stable in RRMS and SPMS, the proportion of females significantly declined over time in the PPMS group. The overall percentage of patients prescribed a disease-modifying drug increased across the phenotypes from 51% to 57%. Prescription of interferon-based therapies declined in each phenotype, with the greatest declines observed in RRMS and PPMS. The PPMS and SPMS groups had significantly more prescriptions for symptom management than the RRMS group. Depression was the most prevalent clinical condition associated with each phenotype. There was a significant difference in the percentage of patients with depression across the phenotypes (p = 0.03), with the highest among SPMS (44%) compared with RRMS (35%) or PPMS (37%). Significant differences (p<0.05) across the phenotypes were also observed for the composite prevalence of cardiovascular conditions (highest in PPMS) and cognitive dysfunction (highest in SPMS).

CONCLUSION

The increasing numbers of patients across each MS phenotype, aging population in patients with MS regardless of phenotype, gender differences and variations across the types of treatments prescribed, and clinical conditions associated with each MS phenotype present new insight into the disease burden and treatment strategies of MS. These should be considered when developing healthcare strategies and optimizing care for patients with MS.