Chemodenervation and Nerve Blocks in the Diagnosis and Management of Spasticity and Muscle Overactivity

Multiple sclerosis and spasticity: the role of anaesthetic nerve blocks on rectus femoris muscle. When should stiff knee be treated with botulinum toxin?

OBJECTIVE

To compare the effect of rectus femoris diagnostic motor nerve blocks (DNB) with anaesthetics and rectus femoris muscle botulinum toxin (BoNT-A) injection in multiple sclerosis patients with unilateral stiff-knee gait.

DESIGN

Prospective observational study Subjects/Patients: Multiple sclerosis patients in stable condition.

METHODS

Patients underwent evaluation before and 1 hour after the anaesthetic block, and 1 month after the botulinum injection. Assessment included a 10-m walking test, a 6-minute walking test, a timed-up-and-go (TUG) test, and a Baseline Expanded Disability Status Scale (EDSS). Post-DNB and post-BoNT-A satisfaction was measured with the global assessment of efficacy scale.

RESULTS

Fourteen patients with unilateral stiff-knee gait due to multiple sclerosis underwent a DNB, among whom 13 received botulinum injections in the rectus femoris muscle after a satisfying test result. Positive post-DNB results correlated with significant functional improvements after BoNT-A. Higher EDSS and longer time from diagnosis correlated with poorer post-DNB and post-BoNT-A absolute outcomes.

CONCLUSION

DNB showed predictive value for BoNT-A outcomes, especially in the case of worse functional status. It effectively predicted endurance and walking speed improvement, while TUG showed greater improvement after botulinum. In cases of uncertain therapeutic benefit, nerve blocks may provide a valuable diagnostic support, particularly in patients with lower functional status.

Enhancing Botulinum Toxin Injection Precision: The Efficacy of a Single Cadaveric Ultrasound Training Intervention for Improved Anatomical Localization

Ultrasound guidance can enhance existing landmark-based injection methods, even through a brief and single exposure during a cadaveric training course. A total of twelve participants were enrolled in this training program, comprising nine physical medicine and rehabilitation specialists, one pediatrician, and two physician assistants. For each participant, one upper-limb muscle and one lower-limb muscle were randomly chosen from the preselected muscle group. Subsequently, participants were tasked with injecting both of their chosen cadaveric muscles with 1 mL of acrylic paint using a manual needle palpation technique, relying solely on their knowledge of anatomic landmarks. Participants then underwent a personalized, one-to-one ultrasound teaching session, lasting approximately five minutes, conducted by two highly experienced instructors. Following this instructive phase, participants were tasked with a second round of injections, targeting the same two muscles in the lower and upper limbs. However, this time, the injections were performed using anatomical landmarks and ultrasound guidance. To facilitate differentiation from the initial injections, a distinct color of acrylic paint was employed. When employing the anatomical landmark-based approach, the overall success rate for injections was 67%, with 16 out of 24 targeted muscles accurately injected. With the incorporation of ultrasound guidance, the success rate was 92%, precisely targeting 22 out of the 24 muscles under examination. There was an improvement in injection accuracy achievable through the integration of ultrasound guidance, even with minimal training exposure. Our single cadaveric ultra-sound training program contributes valuable insights to the utilization of ultrasound for anatomy training to help optimize the targeting of BoNT-A.

Spasticity Treatment Beyond Botulinum Toxins

Botulinum toxin (BonT) is the mainstream treatment option for post-stroke spasticity. BoNT therapy may not be adequate in those with severe spasticity. There are a number of emerging treatment options for spasticity management. In this paper, we focus on innovative and revived treatment options that can be alternative or complementary to BoNT therapy, including phenol neurolysis, cryoneurolysis, and extracorporeal shock wave therapy.

Functional outcomes following surgery for spastic hip adductor muscles in ambulatory and non-ambulatory adults

OBJECTIVE

To evaluate functional outcomes of surgery of spastic hip adductor muscles (obturator neurotomy with or without adductor longus tenotomy) in ambulatory and non-ambulatory patients, using preoperatively defined personalized goals.

DESIGN

Retrospective observational descriptive study.

PATIENTS

Twenty-three patients with adductor spasticity who underwent obturator neurotomy between May 2016 and May 2021 at the Clinique des Cèdres, Cornebarrieu, France, were included.

METHODS

Postoperative functional results were evaluated in accordance with the Goal Attainment Scaling method. Patients were considered "responders" if their score was ≥ 0. Secondary outcomes included spasticity, strength, hip range of motion and change in ambulatory capacity. When data were available, a comparison of pre- and postoperative 3-dimensional instrumented gait analysis was also performed.

RESULTS

Among the 23 patients only 3 were non-walkers. Seventeen/22 patients achieved their main goal and 14/23 patients achieved all their goals. Results were broadly similar for both walking goals (inter-knee contact, inter-feet contact, fluidity, walking perimeter, toe drag) and non-walking goals (intimacy, transfer, pain, posture, dressing).

CONCLUSION

Surgery of spastic hip adductor muscles results in functional improvement in ambulation, hygiene, dressing and posture and can be offered to patients with troublesome adductor overactivity. The use of a motor nerve block is recommended to define relevant goals before the surgery.

Safety and effectiveness of ethanol neurolysis with and without onabotulinumtoxinA in children with cerebral palsy

BACKGROUND

OnabotulinumtoxinA is commonly used to relieve spasticity in children with neurologic disorders. Ethanol neurolysis may be used to target more muscles but is less well studied, especially in pediatrics.

OBJECTIVE

To determine the safety and effectiveness of ethanol neurolysis with onabotulinumtoxinA injections compared to only onabotulinumtoxinA injections for the treatment of spasticity in children with cerebral palsy.

DESIGN

Prospective cohort study including patients with cerebral palsy receiving onabotulinumtoxinA and/or ethanol neurolysis from June 2020 to June 2021.

SETTING

Outpatient physiatry clinic.

PATIENTS

A total of 167 children with cerebral palsy not undergoing other treatments during injection period.

INTERVENTIONS

Injection with either onabotulinumtoxinA only (112 children) or a combination of ethanol and onabotulinumtoxinA injections (55 children) using both ultrasound guidance and electrical stimulation.

MAIN OUTCOME MEASURES

A post-procedure evaluation at 2 weeks after injection documented any adverse effects experienced by the child and perceived magnitude of improvement using an ordinal scale from 1 to 5. Multiple linear regression was used to identify and control for covariates including Gross Motor Function Classification System, gender, age, weight, ethnicity, race, and dosage.

RESULTS

Only weight was identified as a confounding factor. When controlled for weight, combined onabotulinumtoxinA and ethanol injections had a greater magnitude of improvement (3.78/5) compared with onabotulinumtoxinA injections alone (3.44/5), a difference of 0.34 points on the rating scale (95% confidence interval: 0.01-0.69; p = .045). However, the difference was not clinically significant. One patient in the onabotulinumtoxinA-only group and two patients in the combined onabotulinumtoxinA and ethanol group reported mild, self-limiting adverse effects.

CONCLUSION

Ethanol neurolysis under ultrasound and electrical stimulation guidance may be a safe and effective treatment for children with cerebral palsy that allows more spastic muscles to be treated than onabotulinumtoxinA alone.

Anatomical landmarks for ultrasound-guided rectus femoris diagnostic nerve block in post-stroke spasticity

Introduction/Purpose

To determine the location of the rectus femoris (RF) motor branch nerve, as well as its coordinates with reference to anatomical and ultrasound landmarks.

Methods

Thirty chronic stroke patients with stiff knee gait (SKG) and RF hyperactivity were included. The motor nerve branch to the RF muscle was identified medially to the vertical line from anterior superior iliac spine and the midpoint of the superior margin of the patella (line AP) and vertically to the horizontal line from the femoral pulse and its intersection point with the line AP (line F). The point of the motor branch (M) was located with ultrasound, and nerve depth and subcutaneous tissue thickness (ST) were calculated.

Results

The coordinates of the motor branch to the RF were 2.82 (0.47) cm medially to the line AP and 4.61 (0.83) cm vertically to the line F. Nerve depth and subcutaneous tissue thickness were 2.71 (0.62) cm and 1.12 (0.75) cm, respectively.

Conclusion

The use of specific coordinates may increase clinicians' confidence when performing RF motor nerve block. This could lead to better decision-making when assessing SKG in chronic stroke patients.

Recommendations for Ultrasound Guidance for Diagnostic Nerve Blocks for Spasticity. What Are the Benefits?

The diagnostic nerve block (DNB) for spasticity is the percutaneous application of an anesthetic to an individual peripheral nerve trunk (mixed motor sensory nerve), nerve branch to a muscle or an intramuscular branch. The DNB causes a temporary paralysis to assess the contribution of muscle(s) on the spastic pattern and may unmask a fully or partially increased joint range of motion. The anesthetic literature supports the use of ultrasound (US) guidance to improve nerve blocks for sensory targets. This communication summarizes the potential advantages that support the use of US to improve DNB technique. Nerves are much smaller than muscle targets and have various known innervation patterns. US allows for rapid localization of the target before injection, particularly in complex anatomy patterns. The nerve trunks are typically found adjacent to or encapsulating blood vessels, which can be quickly identified with or without color Doppler, allowing the clinician to scan from the vessels to the target and avoid intravascular injection. Lower stimulation levels can be used as the targeted muscle(s) can be seen stimulating rather than only on the surface. A shorter needle insertion time and lower stimulation levels should cause less discomfort to the patient. Smaller volumes of anesthetic may be used as the fluid is seen reaching its target and cessation of stimulation is observed. Further study is needed to identify evidence supporting US utilization with electrical stimulation in DNBs for spasticity management, as US use during nerve blocks for perineurial anesthesia has demonstrated improved patient safety and procedural efficiency.

A Bayesian Network Meta-Analysis and Systematic Review of Guidance Techniques in Botulinum Toxin Injections and Their Hierarchy in the Treatment of Limb Spasticity

Accurate targeting of overactive muscles is fundamental for successful botulinum neurotoxin (BoNT) injections in the treatment of spasticity. The necessity of instrumented guidance and the superiority of one or more guidance techniques are ambiguous. Here, we sought to investigate if guided BoNT injections lead to a better clinical outcome in adults with limb spasticity compared to non-guided injections. We also aimed to elucidate the hierarchy of common guidance techniques including electromyography, electrostimulation, manual needle placement and ultrasound. To this end, we conducted a Bayesian network meta-analysis and systematic review with 245 patients using the MetaInsight software, R and the Cochrane Review Manager. Our study provided, for the first time, quantitative evidence supporting the superiority of guided BoNT injections over the non-guided ones. The hierarchy comprised ultrasound on the first level, electrostimulation on the second, electromyography on the third and manual needle placement on the last level. The difference between ultrasound and electrostimulation was minor and, thus, appropriate contextualization is essential for decision making. Taken together, guided BoNT injections based on ultrasound and electrostimulation performed by experienced practitioners lead to a better clinical outcome within the first month post-injection in adults with limb spasticity. In the present study, ultrasound performed slightly better, but large-scale trials should shed more light on which modality is superior.

Management Of Spastic Equinovarus Foot in Children with Cerebral Palsy: An Evaluation of Anatomical Landmarks for Selective Nerve Blocks of the Tibial Nerve Motor Branches

OBJECTIVE

To define the anatomical landmarks of tibial motor nerve branches for selective motor nerve blocks of the gastrocnemii,  soleus and tibialis posterior muscles in the management of spastic equinovarus foot.

DESIGN

Observational study.

PATIENTS

Twenty-four children with cerebral palsy with spastic equinovarus foot.

METHODS

Considering the affected leg length, motor nerve branches to the gastrocnemii, soleus and tibialis posterior muscles were tracked using ultrasonography, and located in the space (vertical, horizontal, deep) according to the position of fibular head (proximal/distal) and a virtual line from the middle of popliteal fossa to the Achilles tendon insertion (medial/lateral).

RESULTS

Location of motor branches was defined as percentage of the affected leg length. Mean coordinates were: for the gastrocnemius medialis 2.5 ± 1.2% vertical (proximal), 1.0 ± 0.7% horizontal (medial), 1.5 ± 0.4% deep; for the gastrocnemius lateralis 2.3 ± 1.4% vertical (proximal), 1.1 ± 0.9% horizontal (lateral), 1.6 ± 0.4% deep; for the soleus 2.1 ± 0.9% vertical (distal), 0.9 ± 0.7% horizontal (lateral), 2.2 ± 0.6% deep; for the tibialis posterior 2.6 ± 1.2% vertical (distal), 1.3 ± 1.1% horizontal (lateral), 3.0 ± 0.7% deep.

CONCLUSION

These findings may help the identification of tibial motor nerve branches to perform selective nerve blocks in patients with cerebral palsy with spastic equinovarus foot.

The Place of Botulinum Toxin in Spastic Hemiplegic Shoulder Pain after Stroke: A Scoping Review

Stroke is a common pathology worldwide, with an age-standardized global rate of new strokes of 150.5 per 100,000 population in 2017. Stroke causes upper motor neuron impairment leading to a spectrum of muscle weakness around the shoulder joint, changes in muscle tone, and subsequent soft tissue changes. Hemiplegic shoulder pain (HSP) is the most common pain condition in stroke patients and one of the four most common medical complications after stroke. The importance of the appropriate positioning and handling of the hemiplegic shoulder for prevention of HSP is therefore of high clinical relevance. Nevertheless, HSP remains a frequent and disabling problem after stroke, with a 1-year prevalence rate up to 39%. Furthermore, the severity of the motor impairment is one of the most important identified risk factors for HSP in literature. Spasticity is one of these motor impairments that is likely to be modifiable. After ruling out or treating other shoulder pathologies, spasticity must be assessed and treated because it could lead to a cascade of unwanted complications, including spastic HSP. In clinical practice, Botulinum toxin A (BTA) is regarded as the first-choice treatment of focal spasticity in the upper limb, as it gives the opportunity to target specifically selected muscles. It thereby provides the possibility of a unique patient tailored focal and reversible treatment for post stroke spasticity. This scoping review aims to summarize the current evidence of BTA treatment for spastic HSP. First, the clinical manifestation and outcome measures of spastic HSP will be addressed, and second the current evidence of BTA treatment of spastic HSP will be reviewed. We also go in-depth into the elements of BTA application that may optimize the therapeutic effect of BTA. Finally, future considerations for the use of BTA for spastic HSP in clinical practice and research settings will be discussed.

Phenol neurolysis in people with spinal cord injury: a descriptive study

STUDY DESIGN

Descriptive study.

OBJECTIVES

The study's main objective was to describe the common targets of phenol neurolysis and review the safety and efficacy of the dose used for this spasticity management procedure in people with spinal cord injury (SCI).

SETTING

An acute rehabilitation hospital.

METHODS

Data from people with SCI who underwent phenol neurolysis procedures for spasticity management between April 2017 and August 2018 were included in this study. We collected demographics and phenol neurolysis procedure-related information.

RESULTS

A total of 66 people with SCI and spasticity underwent phenol neurolysis of 303 nerves over 102 encounters. During these encounters, 97% of procedures were performed using both electrical stimulation and ultrasound guidance. The median (IQR) total volume of 6% aqueous phenol used per encounter was 4.0 (2.0-6.0) ml with a median (IQR) of 1.5 (1.0-2.3) ml per nerve. The most frequent target was the obturator nerve (33%), followed by the pectoral nerves (23%). Immediate post-phenol neurolysis improvement or reduction in spasticity was reported for 92% of all documented encounters. There was no documentation of any post-procedure-related adverse events in this cohort during this specified time frame.

CONCLUSIONS

Our findings suggest that phenol neurolysis can be safely used to manage spasticity in people with SCI under combined electrical stimulation and ultrasound guidance. Further research is required to assess the procedure's safety, efficacy, and cost-effectiveness on patient-reported outcomes compared to other spasticity interventions.

Post Hoc Subgroup Analysis of the BCause Study Assessing the Effect of AbobotulinumtoxinA on Post-Stroke Shoulder Pain in Adults

Botulinum toxin type A is approved for the focal treatment of spasticity; however, the effectiveness of abobotulinumtoxinA (aboBoNT-A) in patients with shoulder pain who have set reduced pain as a treatment goal is understudied. In addition, some patients encounter delays in accessing treatment programs; therefore, the suitability of aboBoNT-A for pain reduction in this population requires investigation. These factors were assessed in aboBoNT-A-naive Brazilian patients in a post hoc analysis of data from BCause, an observational, multicenter, prospective study (NCT02390206). Patients (N = 49, n = 25 female; mean (standard deviation) age of 60.3 (9.1) years; median (range) time since onset of spasticity of 16.1 (0-193) months) received aboBoNT-A injections to shoulder muscles in one or two treatment cycles (n = 47). Using goal attainment scaling (GAS), most patients achieved their goal of shoulder pain reduction after one treatment cycle (72.1%; 95% confidence interval: 57.2-83.4%). Improvements in GAS T-score from baseline, clinically meaningful reductions in pain score at movement, and clinically meaningful increases in passive shoulder abduction angle further improved with repeated treatment more than 4 months later, despite treatment starting at a median of 16.1 months after the onset of spasticity. These findings support the further investigation of aboBoNT-A injections in chronic post-stroke shoulder pain.

[Clinical practice guideline for the treatment of spasticity: Consensus and algorithms]

Spasticity is a complex phenomenon of extremely variable clinical expression, a dynamic and evolutionary process that can condition the activity and treatment of the patient. The current recommendation for early treatment aims to avoid progression and complications, and involves an individualized approach based on a wide range of pharmacological and non-pharmacological measures. This guide results from a forum of expert specialists who faced some frequent uncertainties in the assessment process and therapeutic approach of the spastic patient such as the suitability of initiating treatment, considerations for initiating, continuing and ceasing treatment with botulinum toxin, adjuvant treatments, pain or follow-up. The result is one algorithm of decision for the therapeutic approach of spasticity. Both scientific progress and the exchange of clinical experience on which this guide is based, can support decision-making on some areas of gloom that we find in daily practice.

Pharmacological management of muscle spasticity

Background: Muscle spasticity is a neurologic disorder, which is considered one of the positive signs of upper motor neuron diseases. Spasticity is common after brain or spinal cord injury. Since spasticity results in tendon retraction, muscle weakness, pain, ankylosis, and disability in activities of daily living, treatment is warranted.Current Concepts: Spasticity is usually assessed using the Modified Ashworth Scale or Modified Tardieu Scale. It is treated with various methods, including physical therapy, occupational therapy, orthosis, medication, and surgery. Pharmacological management should be selected according to the location and severity of the symptom and includes oral medications, chemical nerve block, and intrathecal baclofen pump insertion. Oral medications include baclofen, benzodiazepine, dantrolene, and tizanidine. Chemoneurolysis of spasticity is done with botulinum toxin or a mixture of phenol and alcohol.Discussion and Conclusion: Since muscle spasticity affects motor function and activities of daily living, understanding of this symptom and choosing an optimal treatment are necessary. Pharmacologic treatments should be administered with caution especially with the side effects. Optimal treatment of spasticity will bring the best neurological outcome for the patients.

Alcohol Motor Blocks: Case Series and a Narrative Review

Alcohol neurolysis and intramuscular blocks are interventions for spasticity management. Here, we illustrate two clinical cases with spasticity impeding ease of care and pain which required selective alcohol intramuscular blocks with alcohol neurolysis. Post-interventions, both cases demonstrated improvement in pain and joint range of motion which facilitated better positioning and reduced caregiver burden. Pertinent learning points from alcohol neurolysis with intramuscular blocks are discussed concerning therapeutic effectiveness and intervention safety.

A consensus statement on the use of botulinum toxin in pediatric patients

Botulinum toxin has been used in medicine for the past 30 years. However, there continues to be controversy about the appropriate uses and dosing, especially in the pediatric population. A panel of nine pediatric physiatrists from different regions and previous training programs in the United States were nominated based on institutional reputation and botulinum toxin (BoNT) experience. Based on a review of the current literature, the goal was to provide the rationale for recommendations on the administration of BoNT in the pediatric population. The goal was not only to review safety, dosing, and injection techniques but also to develop a consensus on the appropriate uses in the pediatric population. In addition to upper and lower limb spasticity, the consensus also provides recommendations for congenital muscular torticollis, cervical dystonia, sialorrhea, and brachial plexus palsies.

Ergonomic Recommendations in Ultrasound-Guided Botulinum Neurotoxin Chemodenervation for Spasticity: An International Expert Group Opinion

Ultrasound (US)-guided botulinum neurotoxin (BoNT) injections are becoming a mainstay in the treatment of muscle spasticity in upper motor neuron syndromes. As a result, there has been a commensurate increase in US-guided BoNT injection for spasticity training courses. However, many of these courses do not emphasize the importance of ergonomics. This paper aims to highlight the importance of ultrasound ergonomics and presents ergonomic recommendations to optimize US-guided BoNT injection techniques in spasticity management. Expert consensus opinion of 11 physicians (4 different continents; representing 8 countries, with an average of 12.6 years of practice using US guidance for BoNT chemodenervation (range 3 to 22 years)). A search using PubMed, College of Physicians and Surgeons of British Columbia database, EMbase was conducted and found no publications relating the importance of ergonomics in US-guided chemodenervation. Therefore, recommendations and consensus discussions were generated from the distribution of a 20-question survey to a panel of 11 ultrasound experts. All 11 surveyed physicians considered ergonomics to be important in reducing physician injury. There was complete agreement that physician positioning was important; 91% agreement that patient positioning was important; and 82% that ultrasound machine positioning was important. Factors that did not reach our 80% threshold for consensus were further discussed. Four categories were identified as being important when implementing ultrasound ergonomics for BoNT chemodenervation for spasticity; workstation, physician, patient and visual ergonomics. Optimizing ergonomics is paramount when performing US-guided BoNT chemodenervation for spasticity management. This includes proper preparation of the workspace and allowing for sufficient pre-injection time to optimally position both the patient and the physician. Lack of awareness of ergonomics for US-guided BoNT chemodenervation for spasticity may lead to suboptimal patient outcomes, increase work-related injuries, and patient discomfort. We propose key elements for optimal positioning of physicians and patients, as well as the optimal setup of the workspace and provide clinical pearls in visual identification of spastic muscles for chemodenervation.

Ethyl Alcohol Versus Botulinum Toxin A: A Comparative Study of the Visual and Histopathological Outcomes in the Rabbit Anterior Auricular Muscle Model

BACKGROUND

Botulinum toxin has long been known for its paralytic effects at the neuromuscular junction. Although it has been widely used for vascular and nervous tissues, there has been no study of the aesthetic effects of the application of ethanol to muscle tissues to date.

OBJECTIVE

The authors aimed to demonstrate the effects of the application of ethanol to muscle tissues after an intramuscular injection and to compare the effects of botulinum toxin A (BTA) and ethanol.

METHODS AND MATERIALS

A total of 28 rabbits were divided into 4 groups (n = 7 each). Botulinum toxin A (5 units) and different concentrations of ethanol (5 cc) were injected into the left and right anterior auricular muscles of all rabbits, respectively. Ear ptosis was assessed, and histopathological examination was performed after all rabbits were euthanized in the eighth week.

RESULTS

Muscle function was affected earlier in ethanol-treated ears than in botulinum-treated ears; however, the ptotic effect lasted for a significantly shorter duration in ethanol-injected ears than in BTA-applied ears.

CONCLUSION

Ethanol can block muscle function reversibly and can serve as an alternative to BTA, particularly when rapid results are desirable.

Management of Anterocapitis and Anterocollis: A Novel Ultrasound Guided Approach Combined with Electromyography for Botulinum Toxin Injection of Longus Colli and Longus Capitis

Chemodenervation of cervical musculature using botulinum neurotoxin (BoNT) is established as the gold standard or treatment of choice for management of Cervical Dystonia (CD). The success of BoNT procedures is measured by improved symptomology while minimizing side effects and is dependent upon many factors including: clinical pattern recognition, identifying contributory muscles, BoNT dosage, and locating and safely injecting target muscles. In patients with CD, treatment of anterocollis (forward flexion of the neck) and anterocaput (anterocapitis) (forward flexion of the head) are inarguably challenging. The longus Colli (LoCol) and longus capitis (LoCap) muscles, two deep cervical spine and head flexor muscles, frequently contribute to these patterns. Localizing and safely injecting these muscles is particularly challenging owing to their deep location and the complex regional anatomy which includes critical neurovascular and other structures. Ultrasound (US) guidance provides direct visualization of the LoCol, LoCap, other cervical muscles and adjacent structures reducing the risks and side effects while improving the clinical outcome of BoNT for these conditions. The addition of electromyography (EMG) provides confirmation of muscle activity within the target muscle. Within this manuscript, we present a technical description of a novel US guided approach (combined with EMG) for BoNT injection into the LoCol and LoCap muscles for the management of anterocollis and anterocaput in patients with CD.

Botulinum Toxin Injection and Electromyography in Patients Receiving Anticoagulants: A Systematic Review

OBJECTIVE

To identify the different practice patterns of botulinum toxin injection (BTX) and electromyography (EMG) in patients receiving anticoagulation and to evaluate the incidence, reporting, and management of bleeding complications and compartment syndrome from BTX and EMG.

LITERATURE SURVEY

Systematic review of relevant clinical studies in PubMed/Medline and Embase databases using key terms from inception to 31 May 2020. All publications in the English language were included without demographic limits.

METHODOLOGY

A comprehensive search was performed to identify all studies addressing BTX and EMG in patients receiving anticoagulants. Two reviewers independently screened the titles, abstracts, and full texts and extracted data based on a set of predefined inclusion and exclusion criteria. All studies that met the inclusion criteria were assigned their respective levels of evidence using the Joanne Briggs Institute (JBI) Level of Evidence for Effectiveness.

SYNTHESIS

Eighteen studies were included in this review of which there were nine studies each on BTX and EMG. The results indicated heterogeneity in the practice patterns of BTX and EMG in patients taking anticoagulants. These included the decision for continuation of anticoagulant, international normalized ratio (INR) results acceptable to practitioners, the modality for procedure guidance, and surveillance of bleeding complications. In addition, there were variations in the description of targeted muscles and description of needle sizes. The overall incidence of bleeding complications and compartment syndrome rates were low.

CONCLUSIONS

Despite the varied practice in anticoagulated patients undergoing BTX or EMG, practitioners should allow periprocedural continuation of anticoagulants, targeting an INR of 2 to 3 while using the smallest needle (25 gauge or smaller) of appropriate length. Some of the evidence on procedural guidance and complication surveillance were weak and more research in these areas is required.

[Proposal for approach to selective tibial nerve block in spastic patient. A propos of a case]

The most frequent pattern of spasticity in the lower limb is equinovarus foot. Patients with central nervous system injury and severe spasticity, conservative treatment and botulinum toxin type A often have a limited effect. In these cases, nerve blocks can be very useful in deciding our therapeutic action. We present a clinical case as an example of a new ultrasound-guided approach to tibial nerve block, as this is the main nerve involved in equinovarus foot pattern, specific for spastic patients and its usefulness for the clinical management of spasticity.

Medical Updates in Management of Hypertonia

Identifying the subtypes of hypertonia is becoming increasingly important. Treatment strategies, including tone-modulating surgical interventions, medication type and dosing, and chemodenervation, may differ depending on the type of hypertonia present. It is important to delineate how hypertonia interferes with function and quality of life so that the appropriate intervention can be selected at the right time. Outcomes of treatment depend heavily on clear communication of goals. Botulinum toxin should not be used in isolation but as an adjunct to rehabilitation modalities.

Lower Extremity Problem-Solving: Challenging Cases

Lower limb dysfunction associated with upper motor neuron syndrome can be complex due to interaction of muscle overactivity, weakness, impaired motor control, and contracture. Treatment should be goal-directed and address the patient's passive and active functional impairments in addition to their symptoms. Therefore, a comprehensive, multidisciplinary team approach tailored to each patient's unique needs and functional goals is warranted. This article reviews the evaluation and management of issues related to lower limb muscle overactivity and how this approach was applied to 3 challenging cases.

Intrathecal Therapies

Intrathecal baclofen therapy is a well-established technique for spasticity management. This article briefly reviews the pharmacology of intrathecal baclofen as well as customary approach for utilization of this targeted drug delivery concept. Following these descriptions, four unusual presentations will be described, including the need for initial trialing, patient-directed boluses during chronic intrathecal baclofen therapy, use of medications other than baclofen for intrathecal therapy in spastic patients, and intraventricular baclofen delivery. These hypothetical cases are provided in an effort to expand the use of targeted drug delivery to larger population of spastic patients.

Orthopaedic surgery for patients with central nervous system lesions: Concepts and techniques

Since ancient times, the aim of orthopedic surgery has been to correct limb and joint deformities, including those resulting from central nervous system lesions. Recent developments in the treatment of spasticity have led to changes in concepts and management strategies. The increase in life expectancy has increased the functional needs of patients. Orthopedic surgery, along with treatments for spasticity, improves the functional capacity of patients with neuro-orthopaedic disorders, improving their autonomy. In this paper, we describe key moments in the history of orthopedic surgery regarding the treatment of patients with central nervous system lesions, from poliomyelitis to stroke-related hemiplegia, from the limbs to the spine, and from contractures to heterotopic ossification. A synthesis of the current surgical techniques is then provided, and the importance of multidisciplinary evaluation and management is highlighted, along with indications for medical, rehabilitation and surgical treatments and their combinations. We explain why it is essential to consider patients' expectations and to set achievable goals, particularly before surgery, which is by nature irreversible. More recently, specialized surgical teams have begun to favor the use of soft-tissue techniques over bony and joint procedures, except for spinal disorders. We highlight that orthopedic surgery is no longer the end-point of treatment. For example, lengthening a contractured muscle improves the balance around a joint, improving mobility and stability but may be only part of the problem. Further medical treatment and rehabilitation, or additional surgery, are often necessary to continue to improve the function of the limb. Despite the recognized effectiveness of orthopedic surgery for neuro-orthopedic disorders, few studies have formally evaluated them. Hence, there is a need for research to provide evidence to support orthopedic surgery for treating neuro-orthopedic disorders.

Ultrasound Guidance for Botulinum Neurotoxin Chemodenervation Procedures

Injections of botulinum neurotoxins (BoNTs) are prescribed by clinicians for a variety of disorders that cause over-activity of muscles; glands; pain and other structures. Accurately targeting the structure for injection is one of the principle goals when performing BoNTs procedures. Traditionally; injections have been guided by anatomic landmarks; palpation; range of motion; electromyography or electrical stimulation. Ultrasound (US) based imaging based guidance overcomes some of the limitations of traditional techniques. US and/or US combined with traditional guidance techniques is utilized and or recommended by many expert clinicians; authors and in practice guidelines by professional academies. This article reviews the advantages and disadvantages of available guidance techniques including US as well as technical aspects of US guidance and a focused literature review related to US guidance for chemodenervation procedures including BoNTs injection.

Localization of nerve entry points as targets to block spasticity of the deep posterior compartment muscles of the leg

To identify the optimal body surface puncture locations and the depths of nerve entry points (NEPs) in the deep posterior compartment muscles of the leg, 60 lower limbs of thirty adult cadavers were dissected in prone position. A curved line on the skin surface joining the lateral to the medial epicondyles of the femur was taken as a horizontal reference line (H). Another curved line joining the lateral epicondyle of the femur to the lateral malleolus was designated the longitudinal reference line (L). Following dissection, the NEPs were labeled with barium sulfate and then subjected to spiral computed tomography scanning. The projection point of the NEP on the posterior skin surface of the leg was designated P, and the projection in the opposite direction across the transverse plane was designated P'. The intersections of P on H and L were identified as P_H and P_L , and their positions and the depth of the NEP on PP' were measured using the Syngo system and expressed as percentages of H, L, and PP'. The P_H points of the tibial posterior, flexor hallucis longus and flexor digitorum longus muscles were located at 38.10, 46.20, and 55.21% of H, respectively. The P_L points were located at 25.35, 41.30, and 45.39% of L, respectively. The depths of the NEPs were 49.11, 54.64, and 55.95% of PP', respectively. The accurate location of these NEPs should improve the efficacy and efficiency of chemical neurolysis for treating spasticity of the deep posterior compartment muscles of the leg. Clin. Anat. 30:855-860, 2017. © 2017 Wiley Periodicals, Inc.

Successive motor nerve blocks to identify the muscles causing a spasticity pattern: example of the arm flexion pattern

Botulinum Toxin A has been the main treatment for spasticity since the beginning of the 1990s. Surprisingly, there is still no consensus regarding injection parameters or, importantly, how to determine which muscles to target to improve specific functions. The aim of this study was to develop a systematic approach to determine this, using the example of the arm flexion pattern. We first determined anatomical landmarks for selective motor block of the brachialis nerve, using 20 forearms from 10 fresh cadavers in Ecole Européenne de Chirurgie and a university-based dissection centre, Paris, France. We then carried out selective blocks of the motor nerves to the brachialis, brachioradialis and biceps brachii in patients with stroke with an arm flexion pattern, in a University Rehabilitation Hospital, Garches, France. We measured: the resting angle of the elbow angle in standing (manual goniometer), active and passive range of extension, and spasticity using the Held and Tardieu and the Modified Ashworth scales. Range of passive elbow extension was also measured with the shoulder in 90° of flexion. The resting angle of the elbow in standing decreased by 35.0° (from 87.6 ± 23.7 to 52.6 ± 24.2°) with inhibition of brachialis, by a further 3.9° (from 52.6 ± 24.2 to 48.7 ± 23.7°) with inhibition of brachioradialis and a further 14.5° (from 48.7 ± 23.7to 34.2 ± 20.7°) with inhibition of biceps brachii. These results were consistent with the clinical evaluation of passive elbow range of motion with the shoulder at 90°. Sequential blocking of the nerves to the three main elbow flexors revealed that the muscle that limited elbow extension the most, was brachialis. This muscle should be the main target to improve the arm flexion pattern. These results show that it is important not simply to inject the most superficial or powerful muscles to treat a spastic deformity. A comprehensive assessment is required. The strategy proposed in this paper should increase the effectiveness of botulinum toxin injections by ensuring that the relevant muscles are targeted.

Presentation of Neurolytic Effect of 10% Lidocaine after Perineural Ultrasound Guided Injection of a Canine Sciatic Nerve: A Pilot Study

BACKGROUND

Phenol and alcohol have been used to ablate nerves to treat pain but are not specific for nerves and can damage surrounding soft tissue. Lidocaine at concentrations > 8% injected intrathecal in the animal model has been shown to be neurotoxic. Tests the hypothesis that 10% lidocaine is neurolytic after a peri-neural blockade in an ex vivo experiment on the canine sciatic nerve.

METHODS

Under ultrasound, one canine sciatic nerve was injected peri-neurally with 10 cc saline and another with 10 cc of 10% lidocaine. After 20 minutes, the sciatic nerve was dissected with gross inspection. A 3 cm segment was excised and preserved in 10% buffered formalin fixative solution. Both samples underwent progressive dehydration and infusion of paraffin after which they were placed on paraffin blocks. The sections were cut at 4 µm and stained with hemoxylin and eosin. Microscopic review was performed by a pathologist from Henry Ford Hospital who was blinded to which experimental group each sample was in.

RESULTS

The lidocaine injected nerve demonstrated loss of gross architecture on visual inspection while the saline injected nerve did not. No gross changes were seen in the surrounding soft tissue seen in either group. The lidocaine injected sample showed basophilic degeneration with marked cytoplasmic vacuolation in the nerve fibers with separation of individual fibers and endoneurial edema. The saline injected sample showed normal neural tissue.

CONCLUSIONS

Ten percent lidocaine causes rapid neurolytic changes with ultrasound guided peri-neural injection. The study was limited by only a single nerve being tested with acute exposure.

Chemodenervation for treatment of limb spasticity following spinal cord injury: a systematic review

STUDY DESIGN

Systematic review.

OBJECTIVES

To systematically review the literature on chemodenervation with botulinum toxin (BoNT) or phenol/alcohol for treatment of limb spasticity following spinal cord injury (SCI).

SETTING

British Columbia, Canada.

METHODS

EMBASE, MEDLINE, CINAHL, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials were searched for English language studies published up until March 2014. Studies were assessed for eligibility and quality by two independent reviewers.

RESULTS

No controlled trials were identified. A total of 19 studies were included: 9 involving BoNT and 10 involving phenol/alcohol. Owing to the clinically diverse nature of the studies, meta-analysis was deemed inappropriate. The studies produced level 4 and level 5 evidence that chemodenervation with BoNT or alcohol/phenol can lead to improvement in outcome measurements classified in the body structure and function, as well as activity domains of the International Classification of Functioning, Disability and Health framework. The Modified Ashworth Scale (MAS) was the most commonly used outcome measure. All six studies on BoNT and three of the four studies on phenol/alcohol measuring MAS reported a decrease in at least one point. An improvement in MAS was not always associated with improvement in function. The effect of phenol/alcohol has the potential to last beyond 6 months; study follow-up did not occur beyond this time point.

CONCLUSION

Chemodenervation with BoNT or phenol/alcohol may improve spasticity and function in individuals with SCI. However, there is a lack of high-quality evidence and further research is needed to confirm the efficacy of these interventions.

Controlled nerve ablation with direct current: parameters and mechanisms

Spastic hypertonus (muscle over-activity) often develops after spinal cord injury or stroke. Chemodenervating agents such as Botulinum toxin A (BtA) and phenol are often used to treat this condition. We have previously shown that the use of direct current (DC) to create controlled lesions of peripheral nerves may provide a means of reducing spastic hypertonus. Here, we explored a range of stimulation parameters that could be used clinically. Nerves were lesioned with DC in chronically implanted animals and the outcome was tracked over many months. In addition, we used DC to ablate nerves in animals with decerebrate rigidity (an animal model of spastic hypertonus) and we explored the possible mechanisms of DC nerve ablation. We found that nerve ablation with DC was effective in reducing hypertonus. Some stimulation paradigms were more likely to be clinically acceptable than others. Furthermore we showed that nerve regeneration occurs in the months following DC nerve ablation and we demonstrated that the ablation procedure is repeatable, much like BtA treatment. Regarding mechanism, our results did not support the hypothesis that DC caused nerve damage by overactivating sodium channels. Rather, the mechanism of damage seems to be related to changes in pH.

Optimal management for people with severe spasticity

Spasticity is characterized by velocity-dependent increase in tonic stretch reflexes and tendon jerks. Many people affected by spasticity receive late treatment, or no treatment, which greatly reduces the potential to regain full motor control and restore function. There is much to consider before determining treatment for people with spasticity. Treatment of pediatric patients increases the complexity, because of the substantial difference between adult and pediatric spasticity. Proper patient evaluation, utilization of scales and measures, and obtaining patient and caregiver history is vital in determining optimal spasticity treatment. Further, taking into consideration the limitations and desires of individuals serve as a guide to best management. We have grouped contributing factors into the IDAHO Criteria to elucidate a multidisciplinary approach, which considers a person's complete field of experience. This model is applied to goal setting, and recognizes the importance of a spasticity management team, comprising the treatment subject, his/her family, the environment, and a supportive, well-informed medical staff. The criteria take into account the complexity associated with diagnosing and treating spasticity, with the ultimate goal of improved function.

Role of oral medications in spasticity management

Oral medications are frequently used to manage spasticity. Some clinicians may believe that oral medications are a more conservative or "first-line" strategy to treat this condition. However, their use may lead to significant adverse events. Additionally, efficacy has not been well-established, in particular the ability of these medications to enhance functional outcome. The decision regarding the use of oral medications is further complicated by the fact that a number of different agents have been used for many different diagnoses. The relative dearth of well-controlled studies makes the choice of medications for a given clinical condition even more difficult. This article reviews the mechanisms of action of some of the medications that are more commonly used to treat spasticity and identifies some studies that may suggest efficacy, or lack thereof, for certain diagnoses. Because questions remain regarding the benefit of oral medications, potential side effects also are emphasized to help the reader consider both potential risks and benefits. The article is intended as a broad overview, rather than comprehensive review of the literature.