Intramuscular Injection Of Botulinum Toxin Research Articles

Parietal abdominal pain with lower leg discrepancy: a case report

BackgroundThis report involves the first publication describing a case of parietal abdominal pain due to lower limb length discrepancy.Case presentationA Caucasian male patient in his 50s was referred to our rehabilitation department with chronic abdominal pain that began in childhood. This chronic pain was associated with episodes of acute pain that were partially relieved by grade 3 analgesics. The patient was unable to sit for long periods, had recently lost his job, and was unable to participate in recreational activities with his children. Investigations revealed contracture and hypertrophy of the external oblique muscle and an limb length discrepancy of 3.8 cm (1.5 inches) in the left lower limb. The patient was effectively treated with a heel raise, physiotherapy, intramuscular injection of botulinum toxin, and lidocaine. The patient achieved the therapeutic goals of returning to work, and reducing analgesic use.ConclusionsStructural misbalances, as may be caused by lower leg discrepancy, may trigger muscular compensations and pain. Complete anamnesis and clinical examination must not be trivialized and may reveal previously ignored information leading to a proper diagnosis.

Comparison of Wrinkle Patterns Generated by Intradermal and Intramuscular Botulinum Toxin Injections by Clinical Evaluation

Comparison of Wrinkle Patterns Generated by Intradermal and Intramuscular Botulinum Toxin Injections by Clinical Evaluation

Cutaneous Allergic Reaction to Intramuscular Botulinum Toxin Injection for Spasticity – A Case Report

Cutaneous Allergic Reaction to Intramuscular Botulinum Toxin Injection for Spasticity – A Case Report

Localisation of the centre of the highest region of muscle spindle abundance of anterior forearm muscles.

The centre of the highest region of muscle spindle abundance (CHRMSA) in the intramuscular nerve-dense region has been suggested as the optimal target location for injecting botulinum toxin A to block muscle spasms. The anterior forearm muscles have a high incidence of spasticity. However, the CHRMSA in the intramuscular nerve-dense region of the forearm anterior muscle group has not been defined. This study aimed to accurately define the body surface position and the depth of CHRMSA in an intramuscular nerve-dense region of the anterior forearm muscles. Twenty-four adult cadavers (57.7 ± 11.5 years) were included in this study. The curved line close to the skin connecting the medial and lateral epicondyles of the humerus was designated as the horizontal reference line (H line), and the line connecting the medial epicondyle of the humerus and the ulnar styloid was defined as the longitudinal reference line (L line). Modified Sihler's staining, haematoxylin-eosin staining and computed tomography scanning were employed to determine the projection points (P and P') of the CHRMSAs on the anterior and posterior surfaces of the forearm. The positions (PH and PL) of point P projected onto the H and L lines, and the depth of each CHRMSA, were determined using the Syngo system. The PH of the CHRMSA of the ulnar head of pronator teres, humeral head of pronator teres, flexor carpi radialis, palmaris longus, flexor carpi ulnaris, ulnar part of flexor digitorum superficialis, radial part of flexor digitorum superficialis, flexor pollicis longus, ulnar part of flexor digitorum profundus, radial portion of flexor digitorum profundus and pronator quadratus muscles were located at 42.48%, 45.52%, 41.20%, 19.70%, 7.77%, 25.65%, 47.42%, 53.47%, 12.28%, 38.41% and 51.68% of the H line, respectively; the PL were located at 18.38%, 12.54%, 28.83%, 13.43%, 17.65%, 32.76%, 57.32%, 64.12%, 20.05%, 45.94% and 88.71% of the L line, respectively; the puncture depths were located at 21.92%, 27.25%, 23.76%, 18.04%, 15.49%, 31.36%, 26.59%, 41.28%, 38.72%, 45.14% and 53.58% of the PP' line, respectively. The percentage values are the means of individual values. We recommend that the body surface puncture position and depth of the CHRMSA are the preferred locations for the intramuscular injection of botulinum toxin A to block anterior forearm muscle spasms.

Virtual Reality for Decreasing Procedural Pain during Botulinum Toxin Injection Related to Spasticity Treatment in Adults: A Pilot Study.

Botulinum toxin injections are commonly used for the treatment of spasticity. However, injection procedures are associated with pain and procedural anxiety. While pharmacological approaches are commonly used to reduce these, innovative technology might be considered as a potential non-pharmacological alternative. Given this context, immersive virtual reality (VR) has shown effectiveness in the management of procedural pain. Our retrospective pilot study aimed to assess the potential added value of virtual reality in the management of pain and anxiety during intramuscular injections of botulinum toxin. Seventeen adult patients receiving botulinum toxin injections were included. A numerical rating scale was used to assess pain and anxiety during the injection procedure. The patients reported the pain experienced during previous injections without VR before injection and the pain experienced in the current procedure with VR after the end of the procedure. The level of satisfaction of VR experience, whether or not they agreed to reuse VR for the subsequent toxin botulinum injection, and whether or not they would recommend VR to other patients were assessed. The use of virtual reality led to a decrease of 1.8 pain-related points compared to the procedure without technology. No significant improvement in the level of anxiety was reported. Patients were very satisfied with their VR experiences (7.9 out of 10), and many would agree to reuse VR in their next injection procedure (88%) and to recommend the use of VR in other patients (100%). VR was useful for managing procedural pain related to botulinum toxin injection in adults, with a high level of satisfaction reported by the patients. VR should be considered as a valuable alternative to pharmacological approaches to manage procedural pain during botulinum toxin injection in adults.

An analysis of the efficacy of botulinum neurotoxin type a in treating cervical dystonia

BACKGROUND: The first-line treatment for cervical dystonia (CD) consists of repeated intramuscular injections of botulinum toxin (BoNT). However, the efficacy in some patients may be unsatisfactory and they may discontinue treatment. OBJECTIVE: To examine the factors associated with the maximum rate of remission in patients with CD after initial botulinum neurotoxin type A (or botulinum toxin type A abbreviated as BTX-A or BoNT-A) treatment. METHODS: Patients with CD who received BoNT-A injections were evaluated using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and the Tsui scale, with follow-up endpoints lasting until the start of the second injection. Patients who did not receive a second injection of BoNT-A were followed up for at least 5 months. The maximum remission rates were determined using the lowest Tsui and TWSTRS total scores during the follow-up period. We obtained basic information about these patients such as age, gender, duration of disease, presence of additional disease, types of torticollis, presence of anxiety, depression, tremors, single-photon emission computed tomography (SPECT) findings, injected dose, and so on from their medical records. RESULTS: A total of 70 patients with CD participated in this study, with males comprising 35.7% (25 individuals) with an average age of 45 ± 14 years old. The duration of disease was an independent risk factor for determining whether a complete remission has been attained using the Tsui scale (odds ratio [OR] = 0.978, 95% confidence interval [CI]: 0.959–0.997, P= 0.026). The optimal cut-off point for predicting patients who were unable to achieve complete remission based on duration of disease was 7.5 months (AUG = 0.711). Patients with CD with additional disease had greater difficulty achieving complete remission than those with CD alone based on TWSTRS assessments (P= 0.049). During the study, approximately 17% of all participants reported experiencing adverse reactions that lasted between 1 to 3 weeks before disappearing. CONCLUSION: BoNT is an effective and safe method for treating CD. The maximum remission rates of patients after their first injections are influenced by the duration of their disease. Thus, treatment using BoNT injections must be administered as soon as possible.

Post-Stroke Spastic Movement Disorder and Botulinum Toxin A Therapy: Early Detection And Early Injection.

Post-stroke spastic movement disorder (PS-SMD) develops in up to 40% of stroke survivors after a first ever stroke within the first year. Chronic PS-SMD is often associated with severe disabilities and complications, emphasizing the importance of its early recognition and early adequate management. Extensive research has aimed to accurately predict and sensitively detect a PS-SMD. Symptomatic therapies include conventional rehabilitation and local intramuscular injections of botulinum toxin A (BoNT-A). The latter is widely used, but primarily in the chronic phase of stroke. However, recent studies have shown the safety and efficacy of BoNT-A therapy even in the acute phase and early sub-acute phase after stroke, i.e., within three months post-stroke, leading to an improved long-term outcome in stroke rehabilitation. Local BoNT-A injections evolve as the primary approach in focal, multifocal, and segmental chronic or acute/subacute PS-SMD. Patients at high risk for or manifest PS-SMD should be identified by an early spasticity risk assessment. By doing so, PS-SMD can be integral part of the patient-centered goal-setting process of a multiprofessional spasticity-experienced team. The benefit of an early PS-SMD treatment by BoNT-A should predominate putative degenerative muscle changes due to long-term BoNT-A therapy by far. This, as early treatment effectively avoids complications typically associated with a PS-SMD, i.e., contractures, pain, skin lesions. The management of PS-SMD requires a comprehensive and multidisciplinary approach. Early assessment, patient-centered goal setting, early intervention, and early use of BoNT-A therapy prevents from PS-SMD complications and may improve rehabilitation outcome after stroke.

Wide range applications of botulinum toxin in medicine - literature review

Introduction and purpose : Botulinum toxin is one of the most dangerous natural toxins. Botulinum toxin poisoning causes botulism. Botulism is a set of systemic symptoms resulting from flaccid muscle paralysis. The first symptomatology of toxin poisoning was described at the beginning of the 19th century. After more than 200 years, botulinum toxin is associated primarily with aesthetic medicine treatments, where it is used to temporarily improve the appearance, mainly by reducing mimic wrinkles. Aim of the study: The aim of the study is to collect information available in PubMed, Google Scholar, academic textbooks and characteristics of botulinum toxin medicinal products, especially regarding its wide use, mechanism of action, adverse events and contraindications. As a result, the presentation of the versatile use of botulinum toxin as a medicinal product in many fields of medicine. Brief description of the state of knowledge: Botulinum toxin is produced by the anaerobic bacteria Clostridium botulinum. Its mechanism of action consists in flaccid muscle paralysis. Most preparations with botulinum toxin are only registered for strictly defined aesthetic medicine treatments. Other registered indications for the use of medicinal products with botulinum toxin include overactive bladder, various types of spasticity and prevention of headaches. In addition, in medicine, botulinum toxin is commonly used off-label. Summary: Botulinum toxin is widely used not only in aesthetic medicine. Intramuscular injections of botulinum toxin are successfully used in various fields of medicine, such as: urology, neurology, ophthalmology, gastroenterology, dermatology, gynecology, otolaryngology, dentistry and even psychiatry.

Double vision due to lateral rectus injury after cosmetic botulinum toxin injections.

Facial intramuscular injections of Botulinum toxin (BoNT) injections are among the most common cosmetic procedures in dermatology. Rarely, serious adverse reactions such as blepharoptosis, diplopia and periorbital hematoma may occur with improper administration technique. Here we report a case of painless diplopia 5 weeks post-BoNT injection for 'crow's feet' likely due to inadvertent BoNT diffusion into the lateral rectus muscle causing a temporary palsy. This case aims to raise awareness of proper cosmetic BoNT injection techniques in the periorbital area to avoid ophthalmic complications.

Comparison of Two Versus Three Bilateral Botulinum Toxin Injections Prior to Abdominal Wall Reconstruction.

Background: Intramuscular injection of botulinum toxin A (BTA) induces a temporary muscle paralysis. In patients with a ventral hernia, preoperative injection of BTA in the muscles of the lateral abdominal wall (LAW) leads to thinning and lengthening of these muscles, making fascial closure more likely. In many hernia centres, treatment with BTA prior to abdominal wall reconstruction has therefore become standard care. However, evidence on the optimal BTA strategy is lacking. Methods: In this single-centre retrospective study, we analysed a consecutive cohort of ventral hernia patients that underwent bilateral BTA injections prior to abdominal wall reconstruction with available CT before and after BTA. We only included patients that were treated with exactly 600 units of Dysport®, diluted into 120mL of saline, via either two- or three injections on each side into all three LAW muscle layers. The primary outcome was the change in LAW muscle length and thickness, comparing CT measures from before BTA and 4-6weeks after the injections. Results: We analysed 67 patients; 30 had received two injections bilaterally and 37 had received three injections bilaterally. Baseline data showed no significant differences in LAW muscle thickness or length between groups. In both groups, the median LAW muscle thickness decreased with 0.5cm (p < 0.001). The LAW muscle length increased with 0.9cm (p = 0.001) and 1.2cm (p < 0.001) in the two- and three bilateral injection group, respectively. The BTA-induced changes in LAW thickness and length were not significantly different between both groups (p = 0.809 and p = 0.654, respectively). Discussion: When using the exact same dosage and distribution volume of BTA in patients with a complex abdominal wall defect, two injections bilaterally in the lateral abdominal wall muscles are as effective as three injections bilaterally.

Optimizing the results of facial animation surgery: Botulinum toxin injection into free functional gracilis flap transfer

Although neuromuscular gracilis transplantation is the best choice for facial reanimation in patients with congenital or inveterate palsy, the results are not completely satisfactory. Ancillary procedures developed to achieve better symmetry of the smile and reduce the hypercontractility of the transplanted muscle have been reported. However, the intramuscular injection of botulinum toxin has not been described for this purpose. Patients undergoing gracilis injections of botulinum toxin after facial reanimation surgery between September 1, 2020, and June 1, 2022, were retrospectively enrolled in this study. We collected photographs taken before and 20-30 days after injection and compared the symmetry of the face using software. Nine patients with a mean age of 23.56 years (range, 7-56 years) were enrolled. Reinnervation of the muscle was provided by the contralateral healthy facial nerve via a sural cross-graft (four patients), by the ipsilateral masseteric nerve (three cases), and by the contralateral masseteric and facial nerve (two). Using Emotrics software, we identified differences in the commissure excursion discrepancy of 3.82mm, the smile angle discrepancy of 0.084°, and the dental show discrepancy of 1.49mm; the average difference in the commissure height deviation was 2.26mm (P=0.02), and those in the upper- and lower-lip height deviation were 1.05mm and 1.49mm, respectively. Gracilis injection of botulinum toxin after gracilis transplantation is a safe and feasible procedure that could be applicable to all patients with asymmetric smiles related to excessive transplant contraction. It yields good esthetic results with little to no related morbidity.

Plant Toxins as Potential Alternatives to Botulinum Toxin for Eye-Movement Disorder Therapy

The most successful alternative to traditional surgery for ocular muscle spasm treatment is the intramuscular injection of botulinum toxin (BTX), which allows the maintenance of the muscle dynamics and the absence of scars. However, the main BTX disadvantage is its nonpermanent effect. A possible way for overcoming this obstacle could be represented by the enzymatic surgery using plant toxins known as ribosome-inactivating proteins (RIPs). In this paper, two highly toxic RIPs, namely, ricin and stenodactylin, were considered in a preliminary study for their possible use in the treatment of strabismus and oculofacial dystonias, as alternatives to BTX. Both RIPs showed a strong cytotoxic effect against rhabdomyosarcoma cell lines and myotube differentiated cells, with stenodactylin being about 10-fold more toxic than ricin. Moreover, stenodactylin showed a much higher cytotoxicity on myoblasts than on rhabdomyosarcoma cells. In our experimental conditions, stenodactylin did not damage conjunctival cells. Despite the limitations due to in vitro experiments, our data show that the high cytotoxicity of stenodactylin allows the use of a very low dose and, consequently, of very low injection volumes. This can represent a great advantage in the case of in vivo locoregional treatment. Furthermore, it is possible to modulate the chemoablation of myocytes while destroying myoblasts, thus reducing regenerative phenomena. The risk of cytotoxicity to surrounding tissues would be strongly reduced by the low injected volume and the relative resistance of conjunctival cells. In conclusion, our data suggest that stenodactylin and ricin could represent potential candidates to substitute BTX in ocular dystonia therapy.

Preliminary Findings of the Efficacy of Botulinum Toxin in Temporomandibular Disorders: Uncontrolled Pilot Study

Temporomandibular disorders are a common pathology affecting up to 70% of the population, with a maximum incidence in young patients. We used a sample of twenty patients recruited in the Maxillofacial Surgery Service of the University Hospital of Salamanca (Spain), who met the inclusion criteria, with unilateral painful symptomatology of more than three months' duration. All patients were randomly treated by intramuscular and intra-articular injections of botulinum toxin (100 U) in eight predetermined points. Pain symptomatology was assessed by the visual analog scale (VAS) at the different locations, together with joint symptomatology, at baseline and six weeks after treatment. Adverse effects were also evaluated. In 85% of the patients, pain upon oral opening improved and 90% showed improvement in pain upon mastication. A total of 75% of the patients reported improvement in joint clicking/noise. Headaches improved or disappeared in 70% of the patients treated. Despite the limitations of the study and the preliminary results, intramuscular and intra-articular infiltrations with botulinum toxin were effective in the treatment of symptoms associated with temporomandibular disorders (TMDs), with minimal adverse effects.

Canadian Physicians' Use of Intramuscular Botulinum Toxin Injections for Shoulder Spasticity: A National Cross-Sectional Survey.

Spasticity of the upper extremity can result in severe pain, along with many complications that can impair a patient's activities of daily living. Failure to treat patients with spasticity of the upper limb can result in a decrease in the range of motion of joints and contracture development, leading to further restriction in daily activities. We aimed to investigate the practice patterns of Canadian physicians who utilize Botulinum toxin type-A (BoNT-A) injections in the management of shoulder spasticity. 50 Canadian Physical Medicine and Rehabilitation (PM&R) physicians completed a survey with an estimated completion rate of (36.23%). The demographics of the survey participants came from a variety of provinces, clinical settings, and patient populations. The most common muscle injected for shoulder adduction and internal rotation spasticity was the pectoralis major, this was followed by latissimus dorsi, pectoralis minor, subscapularis and teres major. Injection of BoNT-A for problematic post-stroke shoulder spasticity was common, with (81.48%) of participants responding that it was always or often used in their management of post-stroke spasticity (PSS). Dosing of BoNT-A demonstrated variability for the muscle injected as well as the type of toxin used. The goals of the patients, caregivers, and practitioners were used to help guide the management of these patients. As a result, the practice patterns of Canadian physicians who treat shoulder spasticity are varied, due to numerous patient factors. Future studies are needed to analyze optimal treatment patterns, and the development of algorithms to standardize care.

PROSPECT guideline for haemorrhoid surgery

BACKGROUND Haemorrhoidectomy is associated with moderate-to-severe postoperative pain. OBJECTIVE The aim of this systematic review was to assess the available literature and update previous PROSPECT (procedure specific postoperative pain management) recommendations for optimal pain management after haemorrhoidectomy. DESIGN AND ELIGIBILITY CRITERIA A systematic review utilising PROSPECT methodology was undertaken. DATA SOURCES Randomised controlled trials published in the English language from January 1, 2016 to February 2, 2022 assessing postoperative pain using analgesic, anaesthetic, and surgical interventions were identified from MEDLINE, EMBASE and Cochrane Database. RESULTS Of the 371 randomized controlled trials (RCTs) identified, 84 RCTs and 19 systematic reviews, meta-analyses met our inclusion criteria (103 publications). Interventions that improved postoperative pain relief included: paracetamol and nonsteroidal anti-inflammatory drugs or cyclo-oxygenase-2 selective inhibitors, systemic steroids, pudendal nerve block, topical metronidazole, topical diltiazem, topical sucralfate or topical glyceryl trinitrate, and intramuscular injection of botulinum toxin. DISCUSSION This review has updated the previous recommendations written by our group. Important changes are abandoning oral metronidazole and recommending topical metronidazole, topical diltiazem, topical sucralfate, topical glyceryl trinitrate. Botulinum toxin can also be administered. Contemporary publications confirm the analgesic effect of bilateral pudendal nerve block but invalidate recommendations on perianal infiltration. The choice of the surgery is mostly left to the discretion of the surgeons based on their experience, expertise, type of haemorrhoids, and risk of relapse. That said, excisional surgery is more painful than other procedures.

Application of botulinum toxin in the treatment of bruxism

Bruxism is a commonly reported functional para-function of the oral cavity. Its symptoms are quite characteristic and include, above all, excessive clenching and grinding of the teeth. (2) Other complaints most frequently reported by patients are headaches, pain in the temporomandibular joint, excessive tooth abrasion, damage to dentures, waking up at night, visual effect - the so-called "square jaw". The etiology is multifactorial therefore it is difficult to treat its symptoms.&#x0D; Botulinum toxin is a neurotoxin produced by the anaerobic bacteria Clostridium botulinum. Its mechanism is based on the reversible inhibition of acetylcholine release in neuromuscular junctions. Intramuscular injection of botulinum toxin is one of the treatments of bruxism. So far, this method is used off-label. Looking at the promising results of randomized studies on the use of botulinum toxin in bruxism, this may change in the near future. As shown by previous studies, it is not an ideal method, but nevertheless it is one of the most effective and the best for the patient. The downside to the use of botulinum toxin in the treatment of bruxism symptoms are, inter alia, contraindications to the use of this drug and the duration of its action - 3-6 months.&#x0D; This systematic review of selected articles and studies aims to examine the available literature in order to determine the effectiveness of the use of botulinum toxin in the treatment of bruxism and to assess whether it is currently the most effective method.&#x0D; Pubmed and Google Scholar were searched for literature.

A computed tomography study investigating the effects of botulinum toxin injections prior to complex abdominal wall reconstruction

ObjectiveTo explore how intramuscular injection of botulinum toxin A (BTA) affects the lateral abdominal wall (LAW) musculature, abdominal- and hernia dimensions, and muscle structure on computed tomography (CT) in patients scheduled for complex abdominal wall reconstruction (CAWR).MethodsRetrospective analysis of prospectively registered patients who received bilateral intramuscular BTA injections into all three muscles of the LAW. Only patients for which a CT was available before and 3–6 weeks after BTA treatment prior to surgery were analyzed.ResultsFifty-two patients were analyzed. Median hernia width in all patients decreased with 0.4 cm (IQR − 2.1;0.6) (p = 0.023). Median intra-abdominal transverse diameter increased with 0.9 cm (IQR − 0.2;3.3) (p = 0.001) and the intra-abdominal anterior–posterior diameter decreased with 0.5 cm (IQR − 1.3;0.5) (p = 0.017), making the abdomen more oval. Median LAW muscle length increased with 0.9 cm (IQR 0.0;2.4) per side (p < 0.001), muscle thickness decreased with 0.5 cm (IQR − 0.8;− 0.2) (− 25.0%) per side (p < 0.001), and muscle mass decreased with 3.9 cm2 (IQR − 6.4;-1.5) (− 15.8%) per side (p < 0.001). Median HU of the psoas muscles (density) increased with 4.8 HU (IQR 0.4;9.7) (10.3%) per side (p < 0.001). Effects of BTA were more pronounced in patients with a loss of domain (LoD) ≥ 20%.ConclusionsThe main effect of BTA injections is elongation and thinning of the LAW muscles, more than a decrease in hernia width. Concomitantly, the abdomen becomes more oval. An increase of psoas muscles density is seen, associated with offloading of the LAW muscles. Patients with large LoD have a proportionally higher effect of BTA.

P-108 MARJOLIN'S ULCER AS A COMPLICATION OF UNRESOLVED OPEN ABDOMEN

Abstract Introduction Marjolin's ulcer (MU) is a rare cutaneous tumour, commonly associated with chronic wounds with difficult healing. We present a case of UM diagnosed on a persistent unresolved open abdominal closure wound. Materials and Methods 80-year-old male with a history of ruptured infrarenal aortic aneurysm (2010) that required aorto-unifemoral repair. Postoperative period requiring decompressive laparotomy for abdominal compartment syndrome and treated with negative pressure therapy, and impossibility of definitive abdominal closure due to abdominal muscle retraction. Loss of outpatient follow-up for 10 years. Consultation for worsening of the surgical wound with abdominal pain. Examination revealed abdominal incisional hernia M2–4W3 and large abdominal ulcer. Biopsies positive results for squamous cell carcinoma with infiltrative pattern. A computed tomography describes an abdominal wall mass of 14×6×11cm and space-occupying lesion in the left hepatic lobe. Liver biopsy showed a moderately differentiated hepatocarcinoma. Surgical management consist in intramuscular injection of botulinum toxin and en bloc resection of granulation and ulcerated tissue and ileal loop attached to the lesion. Wall reconstruction with anterior separation of components and supraponeurotic mesh. Conclusions Marjolin's ulcer is associated with squamous cell carcinoma with a high rate of metastasis and mortality. This tumour is considered infrequent, of long-term duration and associated with developing societies. In our environment, this neoplasia can develop in patients with open abdomen treated partially or with closure by second intention, so we consider it necessary to have a high index of diagnostic suspicion in these cases and to perform biopsies for its detection.

Analysis of Joint Power and Work During Gait in Children With and Without Cerebral Palsy

PurposeTo compare joint work in the lower limb joints during different sub-phases of the gait cycle between Cerebral Palsy (CP) and healthy children.MethodsEighteen CP and 20 healthy children’s gait data were collected. The CP group included orthoses, intra-muscular injection of botulinum toxin and surgery groups. A motion capture system was used to collect gait data. Joint work was calculated as positive and negative components in six subphases during gait and normalised by speed when comparing the groups.ResultsThe CP group had a slower walking speed, smaller stride length and longer stance phase than the healthy group. Hip max positive work was 0.12 ± 0.02 Jkg−1/ms−1 for the CP group in pre-mid-stance but 0.07 ± 0.01 Jkg−1/ms−1 for the healthy group during the terminal phase. In terminal stance, ankle positive work was significantly lower in the CP group (0.12 ± 0.01) than in the healthy group (0.18 ± 0.01). The knee showed a similar distribution of positive work in the stance phase for the two groups. In the ankle and hip, the CP group had energy generation mainly in midstance while the healthy group was mainly in terminal stance. In the ankle, the CP group had larger energy absorption in mid-stance than the healthy children group, while the CP group showed lower energy generation in the terminal stance phase than seen in the healthy group.ConclusionThe qualitative and quantitative analysis of joint work provides useful information for clinicians in the treatment and rehabilitation of CP patients.

Characteristic Variation of Electromechanical Delay After the Botulinum Toxin Injection in Spastic Biceps Brachii Muscles.

The objective of this study was to characterize the effects of intramuscular botulinum toxin (BT) injections on the electromechanical delay (EMD) in spastic human biceps muscles. The EMD is calculated as the time lag between the muscle activation onset, as recorded from the surface electromyogram (sEMG), and the onset of recorded force. In a cohort of chronic stroke survivors, we compared the computed EMD derived from the spastic (injected) biceps brachii with that from the contralateral muscle. Eight participants were tested before and up to 3 months after a BT injection. At each session, participants followed an isometric trapezoidal force trajectory at 50 and 30%, respectively, of the tested maximum voluntary contraction (MVC). Joint force and sEMG signals were recorded as well. The number of zero crossings (ZC) of the sEMG during the steady-state portion of the task was also computed. The EMD post-BT was found to increase by 64 ± 10% (at 50% MVC) and 93 ± 18% (at 30% MVC) when compared to pre-BT values, while the number of sEMG-ZC, the mean MVC values, and the force-EMD slope exhibited striking reductions. These parameters, calculated on the contralateral side, remained relatively constant across sessions, with the EMD significantly lower and the MVC values much higher. We discuss potential contributing factors to an increase in EMD values on the affected side, both pre- and post-BT. The observed co-variation across sessions of the increased EMD values with the decreased ZC estimates, a surrogate of motor outflow, and, potentially, more compliant muscle fascicles suggests that the altered motor unit (MU) behavior contributes, at least in part, to the delayed force production.