Nonselective lumbosacral ventral-dorsal rhizotomy for the management of lower-limb hypertonia in nonambulatory children with cerebral palsy.

OBJECTIVE: Children with cerebral palsy (CP) often experience medically refractory hypertonia, for which there are surgical therapies including neuromodulation and rhizotomy. Traditional surgical treatment for medically refractory mixed hypertonia or dystonia includes intrathecal baclofen pumps and selective dorsal rhizotomy. A nonselective lumbosacral ventral-dorsal rhizotomy (VDR; ventral and dorsal roots lesioned by 80%-90%) has the potential to address the limitations of traditional surgical options. The authors highlighted the institutional safety and efficacy of nonselective lumbosacral VDR for palliative tone management in nonambulatory patients with more severe CP. METHODS: The authors performed a retrospective analysis of patients who had undergone lumbosacral VDR between 2022 and 2023. Demographic factors, clinical variables, and operative characteristics were collected. The primary outcomes of interest included tone control and quality of life improvement. Secondary outcome measures included, as a measure of safety, perioperative events such as paresthesias. Postoperative complications were also noted. RESULTS: Fourteen patients (7 female) were included in the study. All patients had undergone a T12-L2 osteoplastic laminoplasty and bilateral L1-S1 VDR. Nine patients had quadriplegic mixed hypertonia, 4 had quadriplegic spasticity, and 1 had generalized secondary dystonia. Following VDR, there was a significant decrease in both lower-extremity modified Ashworth Scale (mAS) scores (mean difference [MD] -2.77 ± 1.0, p < 0.001) and upper-extremity mAS scores (MD -0.71 ± 0.76, p = 0.02), with an average follow-up of 3 months. In the patient with generalized dystonia, the lower-extremity Barry-Albright Dystonia Scale score decreased from 8 to 0, and the overall score decreased from 32 to 13. All parents noted increased ease in caregiving, particularly in terms of positioning, transfers, and changing. The mean daily enteral baclofen dose decreased from 47 mg preoperatively to 24.5 mg postoperatively (p < 0.001). Three patients developed wound dehiscence, 2 of whom had concurrent infections. CONCLUSIONS: Lumbosacral VDR is safe, is effective for tone control, and can provide quality of life improvements in patients with medically refractory lower-limb mixed hypertonia. Lumbosacral VDR can be considered for palliative tone control in nonambulatory patients with more severe CP. Larger studies with longer follow-ups are necessary to further determine safety and long-term benefits in these patients.

Safety and efficacy of continuous intrathecal baclofen via cervical catheter tip: a retrospective case series.

OBJECTIVE: Intrathecal baclofen (ITB) is an effective treatment for hypertonia in children involving the implantation of a pump and catheter system. The highest concentration of ITB is at the catheter tip. The catheter tip location is most commonly within the lumbar or thoracic spine. The cervical tip location has traditionally been avoided because of concerns of hypoventilation and pneumonia; however, these complications in cervical compared with thoracic or lumbar placement have not been reliably proven. Some studies have suggested that cervical ITB location better treats upper-extremity hypertonia. There are limited data describing the safety and efficacy of cervical ITB on hypertonia. The authors present a single-institution retrospective case series highlighting the safety and efficacy of using cervical ITB location for the treatment of hypertonia. METHODS: Retrospective data analysis was performed for children who underwent continuous dosing cervical ITB between April 2022 and October 2023. Nonmodifiable risk factors, clinical variables, operative characteristics, and adverse outcomes were collected. RESULTS: This study included 25 patients (8 female). The mean age at implantation was 12.4 years, and the mean operative duration was 90 minutes. The mean Barry-Albright Dystonia Scale score decreased by 9.5 points (p = 0.01). The mean aggregated modified Ashworth scale score in the upper extremities decreased by 2.14 points (p = 0.04), and that in the lower extremities decreased by 4.98 points (p < 0.01). One patient each (4%) had infection and baclofen toxicity. Two patients (8%) had respiratory depression requiring continuous positive airway pressure. There was no incidence of pneumonia or wound dehiscence. CONCLUSIONS: The cervical catheter tip location for ITB is safe, is effective to control tone, and should be considered for the treatment of hypertonia. Larger studies with longer follow-up are necessary to further determine upper-limit dosing safety along with long-term functional benefits in these patients.

The effect of suboccipital muscle dysfunction on the biomechanics of the upper cervical spine: a study based on finite element analysis.

OBJECTIVE: Muscle dysfunction caused by repetitive work or strain in the neck region can interfere muscle responses. Muscle dysfunction can be an important factor in causing cervical spondylosis. However, there has been no research on how the biomechanical properties of the upper cervical spine change when the suboccipital muscle group experiences dysfunction. The objective of this study was to investigate the biomechanical evidence for cervical spondylosis by utilizing the finite element (FE) approach, thus and to provide guidance for clinicians performing acupoint therapy. METHODS: By varying the elastic modulus of the suboccipital muscle, the four FE models of C0-C3 motion segments were reconstructed under the conditions of normal muscle function and muscle dysfunction. For the two normal condition FE models, the elastic modulus for suboccipital muscles on both sides of the C0-C3 motion segments was equal and within the normal range In one muscle dysfunction FE model, the elastic modulus on both sides was equal and greater than 37 kPa, which represented muscle hypertonia; in the other, the elastic modulus of the left and right suboccipital muscles was different, indicating muscle imbalance. The biomechanical behavior of the lateral atlantoaxial joint (LAAJ), atlanto-odontoid joint (ADJ), and intervertebral disc (IVD) was analyzed by simulations, which were carried out under the six loadings of flexion, extension, left and right lateral bending, left and right axial rotation. RESULTS: Under flexion, the maximum stress in LAAJ with muscle imbalance was higher than that with normal muscle and hypertonia, while the maximum stress in IVD in the hypertonic model was higher than that in the normal and imbalance models. The maximum stress in ADJ was the largest under extension among all loadings for all models. Muscle imbalance and hypertonia did not cause overstress and stress distribution abnormalities in ADJ. CONCLUSION: Muscle dysfunction increases the stress in LAAJ and in IVD, but it does not affect ADJ.

Endothelin-1-mediated Brainstem Glial Activation Produces Asthmatic Airway Vagal Hypertonia Via Enhanced ATP-P2X4 Receptor Signaling in Sprague-Dawley Rats.

The occurrence of major asthma symptoms is largely attributed to airway vagal hypertonia, of which the central mechanisms remain unclear. This study tests the hypotheses that endothelin-1-mediated brainstem glial activation produces asthmatic airway vagal hypertonia via enhanced action of adenosine 5'-triphosphate on neuronal purinergic P2X4 receptors. A rat model of asthma was prepared using ovalbumin. Airway vagal tone was evaluated by the recurrent laryngeal discharge and plethysmographic measurement of pulmonary function. The changes in the brainstem were examined using ELISA, Western blot, luciferin-luciferase, quantitative reverse transcription-polymerase chain reaction, enzyme activity assay and immunofluorescent staining, respectively. The results showed that in the medulla of rats, endothelin receptor type B and P2X4 receptors were primarily expressed in astrocytes and neurons, respectively, and both of which, along with endothelin-1 content, were significantly increased after ovalbumin sensitization. Ovalbumin sensitization significantly increased recurrent laryngeal discharge, which was blocked by acute intracisternal injection of P2X4 receptor antagonist 5-BDBD, knockdown of brainstem P2X4 receptors, and chronic intraperitoneal injection of endothelin receptor type B antagonist BQ788, respectively. Ovalbumin sensitization activated microglia and astrocytes and significantly decreased ecto-5'-nucleotidase activity in the medulla, and all of which, together with the increase of medullary P2X4 receptor expression and decrease of pulmonary function, were reversed by chronic BQ788 treatment. These results demonstrated that in rats, allergic airway challenge activates both microglia and astrocytes in the medulla via enhanced endothelin-1/endothelin receptor type B signaling, which subsequently causes airway vagal hypertonia via augmented adenosine 5'-triphosphate/P2X4 receptor signaling in central neurons of airway vagal reflex.

Skin and not dorsal root stimulation reduces hypertonus in thoracic motor complete spinal cord injury: a single case report.

On demand and localized treatment for excessive muscle tone after spinal cord injury (SCI) is currently not available. Here, we examine the reduction in leg hypertonus in a person with mid-thoracic, motor complete SCI using a commercial transcutaneous electrical stimulator (TES) applied at 50 or 150 Hz to the lower back and the possible mechanisms producing this bilateral reduction in leg tone. Hypertonus of knee extensors without and during TES, with both cathode (T11-L2) and anode (L3-L5) placed over the spinal column (midline, MID) or 10 cm to the left of midline (lateral, LAT) to only active underlying skin and muscle afferents, was simultaneously measured in both legs with the pendulum test. Spinal reflexes mediated by proprioceptive (H-reflex) and cutaneomuscular reflex (CMR) afferents were examined in the right leg opposite to the applied LAT TES. Hypertonus disappeared in both legs but only during thoracolumbar TES, and even during LAT TES. The marked reduction in tone was reflected in the greater distance both lower legs first dropped to after being released from a fully extended position, increasing by 172.8% and 94.2% during MID and LAT TES, respectively, compared with without TES. Both MID and LAT (left) TES increased H-reflexes but decreased the first burst, and lengthened the onset of subsequent bursts, in the cutaneomuscular reflex of the right leg. Thoracolumbar TES is a promising method to decrease leg hypertonus in chronic, motor complete SCI without activating spinal cord structures and may work by facilitating proprioceptive inputs that activate excitatory interneurons with bilateral projections that in turn recruit recurrent inhibitory neurons.NEW & NOTEWORTHY We present proof of concept that surface stimulation of the lower back can reduce severe leg hypertonus in a participant with motor complete, thoracic spinal cord injury (SCI) but only during the applied stimulation. We propose that activation of skin and muscle afferents from thoracolumbar transcutaneous electrical stimulation (TES) may recruit excitatory spinal interneurons with bilateral projections that in turn recruit recurrent inhibitory networks to provide on demand suppression of ongoing involuntary motoneuron activity.

Opening Pressure and Post-Lumbar Puncture Headache in Children Undergoing Intrathecal Baclofen Trial.

Aims: Post-lumbar puncture headache occurs in 5% to 12% of children. The purpose of this study was to determine the frequency and predictors of post-lumbar puncture headache in children with hypertonia undergoing lumbar puncture for intrathecal baclofen trial. Methods: This was a retrospective single-center review of all 43 children (<18 years) with hypertonia and/or dyskinesia undergoing intrathecal baclofen trial from 2013-2022. Predictors of post-lumbar puncture headache were evaluated via 2-way paired t test and Fisher exact test. Results: Seven subjects (16.3%) developed post-lumbar puncture headache. Of patients who developed post-lumbar puncture headache, 3 required emergency care or hospitalization. One was misdiagnosed with constipation. The 16 patients without opening pressure measured were excluded from subsequent analyses. Of the 27 patients with documented opening pressure, the mean opening pressure was 24.0 cm H2O (SD 6.5) and 5 (18.5%) had elevated opening pressure (>28 cm H2O). Mean opening pressure was higher for those with post-lumbar puncture headache (28.6 vs 22.4 cm H2O, P = .014). Sixty percent of patients with elevated opening pressure developed post-lumbar puncture headache. Baclofen pumps were placed in 4 (80%) patients with elevated opening pressure and 6 (85.7%) with post-lumbar puncture headaches without complications. Interpretation: The risk of post-lumbar puncture headache after intrathecal baclofen trial was higher than reported in the literature, likely because of greater rates of elevated opening pressure. Physicians may use opening pressure to predict risk for post-lumbar puncture headache and should educate families about symptoms. Elevated opening pressure or post-lumbar puncture headache may not preclude baclofen pump placement.

Variants in tropomyosins TPM2 and TPM3 causing muscle hypertonia.

Patients with myopathies caused by pathogenic variants in tropomyosin genes TPM2 and TPM3 usually have muscle hypotonia and weakness, their muscle biopsies often showing fibre size disproportion and nemaline bodies. Here, we describe a series of patients with hypercontractile molecular phenotypes, high muscle tone, and mostly non-specific myopathic biopsy findings without nemaline bodies. Three of the patients had trismus, whilst in one patient, the distal joints of her fingers flexed on extension of the wrists. In one biopsy from a patient with a rare TPM3 pathogenic variant, cores and minicores were observed, an unusual finding in TPM3-caused myopathy. The variants alter conserved contact sites between tropomyosin and actin.

Para Powerlifting Performance: A Retrospective Analysis Considering Origin of Impairment, Sport Classification, and Sex.

OBJECTIVE: We analyzed the retrospective performance of para powerlifters over 8 yrs considering sex, the origin of impairment, and sport classification of para powerlifting. DESIGN: This retrospective study analyzed data from 6791 (4613 and 2178 for male and female, respectively) individual results from 1634 athletes' performances. We collected absolute load (in kilograms), relative load (in kilogram/body mass), chronological age and origin of impairment (acquired or congenital), and sport classification (leg length difference, limb deficiency, range of movement, impaired muscle power, hypertonia, ataxia, athetosis, and short stature of para powerlifters. RESULTS: Males were stronger than females thorough the years with acquired impairment being stronger than congenital impairment. Para powerlifters with acquired impairment were older compared with congenital impairment over the years. Acquired impairment males won 60% more medals than the congenital group. There was a significant association between competition achievement and sports class classification, with a higher number of medals for limb deficiency than other sports classes. CONCLUSIONS: These results demonstrate that the sex, origin of impairment, and sports classification influence performance of athletes in para powerlifting. Thus, this information can help athletes, coaches, sport managers, and sport institutions involved in the sport of para powerlifting.

From one to many: Hypertonia in schizophrenia spectrum psychosis an integrative review and adversarial collaboration report.

Different types of resistance to passive movement, i.e. hypertonia, were described in schizophrenia spectrum disorders (SSD) long before the introduction of antipsychotics. While these have been rediscovered in antipsychotic-naïve patients and their non-affected relatives, the existence of intrinsic hypertonia vs drug-induced parkinsonism (DIP) in treated SSD remains controversial. This integrative review seeks to develop a commonly accepted framework to specify the putative clinical phenomena, highlight conflicting issues and discuss ways to challenge each hypothesis and model through adversarial collaboration. The authors agreed on a common framework inspired from systems neuroscience. Specification of DIP, locomotor paratonia (LMP) and psychomotor paratonia (PMP) identified points of disagreement. Some viewed parkinsonian rigidity to be sufficient for diagnosing DIP, while others viewed DIP as a syndrome that should include bradykinesia. Sensitivity of DIP to anticholinergic drugs and the nature of LPM and PMP were the most debated issues. It was agreed that treated SSD should be investigated first. Clinical features of the phenomena at issue could be confirmed by torque, EMG and joint angle measures that could help in challenging the selectivity of DIP to anticholinergics. LMP was modeled as the release of the reticular formation from the control of the supplementary motor area (SMA), which could be challenged by the tonic vibration reflex or acoustic startle. PMP was modeled as the release of primary motor cortex from the control of the SMA and may be informed by subclinical echopraxia. If these challenges are not met, this would put new constraints on the models and have clinical and therapeutic implications.

Safety and efficacy of intrathecal baclofen trials for the treatment of hypertonia: a retrospective cohort study.

OBJECTIVE: Intrathecal baclofen (ITB) is an effective treatment for refractory hypertonia in children. ITB has long been effective for the treatment of spasticity, and indications have naturally evolved to include dystonia and mixed pediatric movement disorders (PMDs). The established uses for ITB trials are insurance prerequisite, mixed tone, and family request. Despite agreement for ITB therapy by a multidisciplinary group of subspecialists in a complex PMD program, insurance companies often require an ITB trial be performed. A longitudinal cohort was identified to determine the safety and efficacy of ITB trials and to determine the utility of test dosing in this population. METHODS: Retrospective data analysis was performed for patients with hypertonia who underwent ITB bolus trials at the authors' institution between 2021 and 2023. Nonmodifiable risk factors and clinical variables were collected. RESULTS: Thirty-one patients (11 female) underwent 32 ITB trials. Of these patients, 67.7% had a diagnosis of mixed hypertonia, 32.3% pure spasticity, and 9.1% secondary dystonia. The mean age at test dose was 12.8 years, and 58.1% of patients were born premature. The mode Gross Motor Function Classification System score was 5. The mean difference in Barry-Albright Dystonia Scale (BADS) scores was -7.33 points (p = 0.01) at 2.5 hours postoperatively. The mean difference in upper-extremity modified Ashworth Scale (mAS) scores was -5.36 points (p = 0.003), and that for lower-extremity mAS scores was -6.61 (p < 0.001). In total, 21.9% of patients developed a post-dural puncture headache. Conversion to a permanent baclofen pump was performed in 22/32 (68.8%) patients. Of those who did not pursue pump placement, 1 patient had high surgical risk, 1 had an ineffective response, 1 had a bad reaction to the test dose and cited both regression and increased discomfort, and 2 declined despite an effective trial owing to family preferences. CONCLUSIONS: ITB trials require hospitalization in some form and carry risks of procedural complications. The decision to pursue a trial should be made on a case-by-case basis by clinicians and should not be determined by insurance companies. The complication rate of ITB trials is high, and a test dose is unnecessary in this fragile population.

A Young Woman With Hypertonia, Severe Scoliosis, and Encephalopathy.

A 31-year-old woman was seen with contractures in her fingers and toes, carpal inversion, dysarthria, dysphagia, hypertonia, decreased tendon reflexes, absence of Babinski sign, and no psychiatric problems and significant global atrophy. What is your diagnosis?

Tone management: An environmental scan of current management practices across Canada.

BACKGROUND: Currently, there are no standardized approaches to care or evaluation for tone dysfunction in Canada. The study authors hypothesize that there is significant practice variation across the country. This environmental scan is aimed to describe the current practice for management of paediatric patients with hypertonia across Canada. METHODS: A web-based survey was developed by the authors with a multi-disciplinary approach and sent to representative paediatric rehabilitation sites in each province in Canada. Disciplines at the rehabilitation sites surveyed included all or some of the following disciplines: physiatry, neurology, neurosurgery, plastic surgery, orthopaedic surgery, physiotherapy and occupational therapy. All statistical analyses were performed using the R statistical software version 4.0. Fifteen rehabilitation sites were contacted, and 12 sites were used for the final analysis. RESULTS: Cerebral palsy was found to be the most common diagnosis for tone dysfunction, with 58% of sites diagnosing greater than 20 new patients per year. In 67% of sites, patients were seen within a formal multidisciplinary clinic to manage hypertonia. All 12 sites utilized oral baclofen and gabapentin, and 92% of sites utilized trihexyphenidyl. Botulinum toxin injections were offered at 50% of sites. Upper and lower extremity surgical procedures were offered in 83% of the sites. CONCLUSION: The information gained from this study provides some insight into the current practice across Canada for children with hypertonia. This study may assist in the development of a national, standardized strategy to tone management, potentially facilitating more equitable access to care for patients.

Myofascial urinary frequency syndrome is a novel syndrome of bothersome lower urinary tract symptoms associated with myofascial pelvic floor dysfunction.

This study describes a novel, distinct phenotype of urinary symptoms named "myofascial urinary frequency syndrome" (MUFS) present in one-third of individuals presenting with urinary frequency. In addition to a characteristic symptom constellation suggestive of myofascial dysfunction, MUFS subjects exhibit "persistency": a persistent feeling of needing to urinate regardless of urine volume. On examination, 97% of MUFS patients demonstrated pelvic floor hypertonicity with either global tenderness or myofascial trigger points, and 92% displayed evidence of impaired muscular relaxation, hallmarks of myofascial dysfunction. To confirm this symptom pattern was attributable to the pelvic floor musculature, we confirmed the presence of "persistency" in 68 patients with pelvic floor myofascial dysfunction established through comprehensive examination and electromyography and corroborated by improvement with pelvic floor myofascial release. These symptoms distinguish subjects with myofascial dysfunction from subjects with OAB, IC/BPS, and asymptomatic controls, confirming MUFS is a distinct LUTS symptom complex.

Positional Change Used to Manage Postextubation Respiratory Failure in a Child With Cerebral Palsy.

Dental treatment for patients with cerebral palsy (CP) is often performed under general anesthesia due to involuntary movements that can render dental treatment difficult. Since CP is often accompanied by spasticity, care must be taken when positioning patients during general anesthesia. We report the management of a 14-year-old girl with CP and epilepsy undergoing general anesthesia for dental treatment who experienced respiratory failure due to acute thoracoabdominal muscle hypertonia after extubation. She had a history of cardiac arrest due to respiratory failure caused by acute muscle hypertonia and successful resuscitation. General anesthesia was induced after careful positioning of the patient to prevent spastic muscle stretching, and the dental treatment was completed without complications. However, upon awakening after extubation, the patient developed respiratory failure due to acute muscle hypertonia. The patient was resedated and repositioned from a supine to a sitting position, and her symptoms improved. There was no recurrence of muscle hypertonia, and she recovered fully without complications. In this case, respiratory failure associated with acute muscle hypertonia was successfully managed by position change after initial treatment with positive-pressure ventilation and propofol. It is important to be prepared for the possibility of respiratory failure associated with acute muscle hypertonia and its countermeasures when providing general anesthesia for patients with CP.

Navigated Radiofrequency Ablation Peripheral Rhizotomy for Lumbosacral Hypertonia in a Nonambulatory Patient With Spinal Fusion: Indications, Surgical Techniques, and Lessons Learned.

BACKGROUND AND OBJECTIVES: Radiofrequency ablation (RFA) is a destructive therapy which causes target tissue destruction by application of a thermal dose. Neurosurgical applications of RFA are well-described for myriad chronic pain and movement disorder diagnoses. In fact, RFA pallidotomy and thalamotomy are the initial procedures from which the field of neurosurgical management for movement disorders emerged. RFA rhizotomy for post-traumatic spasms was popular in the 1970s and 1980s, although it was largely abandoned after the invention and Food and Drug Administration approval of intrathecal baclofen therapy. RFA has not been described as a primary treatment of hypertonia in nonambulatory children. METHODS: We report a case of computer-navigated, nonselective RFA peripheral rhizotomy for a nonambulatory child with a history of severe scoliosis and spinal fusion, where an open rhizotomy was technically impractical. RESULTS: Navigation to and ablation of the bilateral L1-L5 peripheral nerves with this approach was successful, and the patient experienced bilateral lower extremity tone improvement. CONCLUSION: We use this case to highlight considerations in indications, our applied operative technique, and lessons learned from this novel application of RFA peripheral rhizotomy in children.

[Sacral neuromodulation for bladder voiding dysfunction: Experience at a French university center]. / Neuromodulation sacrée pour trouble de la vidange vésicale : expérience d'un centre universitaire français.

OBJECTIVE: To report the experience of a university hospital center with sacral neuromodulation for patients with bladder voiding disorders. MATERIAL AND METHODS: All patients who underwent sacral neuromodulation between 1998 and 2022 for bladder voiding disorders were included. Medical records were analyzed retrospectively, and population, efficacy and follow-up data were collected. RESULTS: A total of 134 patients underwent test implantation and 122 patients were analyzed. 68 patients (56%) were implanted with a definitive neuromodulation device. Mean age was 43±16 years and BMI 25.5±5.4kg/m2. 74% were women. Bladder voiding disorder was due to sphincter hypertonia in 51% of cases, with associated bladder hypocontractility in 29%. The spontaneous micturition rate after implantation increased from 34% to 92%. Implantation results appeared to be better in patients with sphincter hypertonia, whether or not associated with bladder hypocontractility. The benefit was most often present with a frequency of 5Hz (54.4%). Side-effects were present in 52% of cases at 5 years, and in 85% of cases were pain in relation to the implanted devices. They resolved under medical treatment or after revision of the device (27% of cases at 5 years). CONCLUSION: SNM is effective in micturition recovery, but has side effects. Urodynamic mechanism and etiology may provide clues for modulating NMS box settings and determining predictive factors for NMS success. Data from other centers are needed to identify reliable predictive factors.

A case of complex hemangioendothelioma of the liver in an infant.

A physical examination of a 9-month-old female infant presenting with vomiting and diarrhea revealed tenderness in the right upper abdomen and heightened abdominal muscle tone. Abdominal ultrasonography identified an irregular hypoechoic area within the right lobe of the liver. While a subsequent enhanced CT examination disclosed a well-defined lesion exhibiting internal focal calcification and delayed heterogeneous enhancement. Subsequently, she underwent surgical resection, and postoperative pathology revealed areas of epithelioid hemangioendothelioma and cavernous hemangioma. Immunohistochemistry demonstrated positive expression of CD34, CD31, FLI-1, and F-VIII. The pathologic diagnosis was confirmed as composite hemangioendothelioma (CHE).

Treatment of spasticity.

Spasticity is characterized by an enhanced size and reduced threshold for activation of stretch reflexes and is associated with "positive signs" such as clonus and spasms, as well as "negative features" such as paresis and a loss of automatic postural responses. Spasticity develops over time after a lesion and can be associated with reduced speed of movement, cocontraction, abnormal synergies, and pain. Spasticity is caused by a combination of damage to descending tracts, reductions in inhibitory activity within spinal cord circuits, and adaptive changes within motoneurons. Increased tone, hypertonia, can also be caused by changes in passive stiffness due to, for example, increase in connective tissue and reduction in muscle fascicle length. Understanding the cause of hypertonia is important for determining the management strategy as nonneural, passive causes of stiffness will be more amenable to physical rather than pharmacological interventions. The management of spasticity is determined by the views and goals of the patient, family, and carers, which should be integral to the multidisciplinary assessment. An assessment, and treatment, of trigger factors such as infection and skin breakdown should be made especially in people with a recent change in tone. The choice of management strategies for an individual will vary depending on the severity of spasticity, the distribution of spasticity (i.e., whether it affects multiple muscle groups or is more prominent in one or two groups), the type of lesion, and the potential for recovery. Management options include physical therapy, oral agents; focal therapies such as botulinum injections; and peripheral nerve blocks. Intrathecal baclofen can lead to a reduction in required oral antispasticity medications. When spasticity is severe intrathecal phenol may be an option. Surgical interventions, largely used in the pediatric population, include muscle transfers and lengthening and selective dorsal root rhizotomy.

Transcriptome and Small RNA Sequencing Reveals the Basis of Response to Salinity, Alkalinity and Hypertonia in Quinoa (Chenopodium quinoa Willd.).

Quinoa (Chenopodium quinoa Willd.) is a dicotyledonous cereal that is rich in nutrients. This important crop has been shown to have significant tolerance to abiotic stresses such as salinization and drought. Understanding the underlying mechanism of stress response in quinoa would be a significant advantage for breeding crops with stress tolerance. Here, we treated the low-altitude quinoa cultivar CM499 with either NaCl (200 mM), Na2CO3/NaHCO3 (100 mM, pH 9.0) or PEG6000 (10%) to induce salinity, alkalinity and hypertonia, respectively, and analyzed the subsequent expression of genes and small RNAs via high-throughput sequencing. A list of known/novel genes were identified in quinoa, and the ones responding to different stresses were selected. The known/novel quinoa miRNAs were also identified, and the target genes of the stress response ones were predicted. Both the differently expressed genes and the targets of differently expressed miRNAs were found to be enriched for reactive oxygen species homeostasis, hormone signaling, cell wall synthesis, transcription factors and some other factors. Furthermore, we detected changes in reactive oxygen species accumulation, hormone (auxin and ethylene) responses and hemicellulose synthesis in quinoa seedlings treated with stresses, indicating their important roles in the response to saline, alkaline or hyperosmotic stresses in quinoa. Thus, our work provides useful information for understanding the mechanism of abiotic stress responses in quinoa, which would provide clues for improving breeding for quinoa and other crops.