Neuromotor effects of short-term and long-term exposures to trichloroethylene in workers

BACKGROUND

Health effects of long-term exposure to organic solvents at low levels are a major concern in industrialized countries. To assess the neuromotor impact of trichloroethylene objectively, static postural sway and hand tremor parameters, along with urinary trichloroethanol (TCOH) and trichloroacetic acid (TCAA) levels, were investigated in 57 workers without obvious neurological disorders and 60 control subjects.

METHODS

The workers had been occupationally exposed to trichloroethylene for 0.1-37 years. The cumulative exposure index (CEI) was calculated from their occupational history and total trichloro-compounds (TCOH + TCAA).

RESULTS

Median levels in the workers were 1.7 mg/L for TCOH and 2.5 mg/L for TCAA, and the maximum ambient trichloroethylene concentration was estimated to be <22 ppm from the previously reported equation using TCOH + TCAA. Sway parameters with eyes open and tremor intensity in dominant hand were significantly larger in the exposed workers than in the control subjects when adjusting for possible confounders. A significant dose-effect association was seen between two sway parameters and urinary TCOH level in the workers. Tremor intensities in non-dominant hand differed significantly among three groups of the workers divided according to the CEI.

CONCLUSIONS

These findings suggest that trichloroethylene exposure, even at low levels of less than the short-term exposure limit by the ACGIH, can affect the neuromotor function of workers. The postural instability appears to result from recent exposure, and the increased tremor may occur due to short-term and long-term exposures. Hereafter, such objective measures, along with subjective symptoms, should be carefully used for the occupational exposure limit setting.

The effects of literate narrative intervention on children with neurologically based language impairments: an early stage study

PURPOSE

This study investigated the effect of a literate narrative intervention on the macrostructural and microstructural language features of the oral narratives of 3 children with neuromuscular impairment and co-morbid receptive and expressive language impairment.

METHOD

Three children, ages 6-8 years, participated in a multiple baseline across participants and language features study. The 3 participants engaged in 10 individual literate narrative intervention sessions following staggered baseline trials. Assessment probes eliciting picture- and verbally prompted narratives were recorded and analyzed.

RESULTS

All three children demonstrated gains in the use of story grammar (macrostructure) and causality (microstructure), with moderate to large effect sizes based on percentage of nonoverlapping data points. Gains were seen in both picture-prompted narratives that were the direct focus of intervention and in verbally prompted narratives that served as a measure of generalization. Other features of microstructure not explicitly targeted during intervention increased in the narratives produced by the participants. Additionally, follow-up data collected 8 months after intervention indicated the maintenance of some skills over time.

CONCLUSION

The results of this study suggest that literate narrative intervention may be useful for improving children's functional use of narrative macrostructure and microstructure, including literate language.

Clinical and biochemical parameters of children and adolescents applying pesticides

BACKGROUND

The primary agricultural product in Egypt is the cotton crop. Children and adolescents work seasonally in the cotton fields applying pesticides.

OBJECTIVE

To examine the effect of pesticide exposure on clinical and biochemical parameters in children and adolescents applying pesticides.

METHODS

Male children currently applying pesticides and aged between 9 and 19 years (n = 50) were recruited for this study. They were asked to complete work, health, and exposure questionnaires; examined for any medical and neurological problems with particular attention to sensory and motor functions including cranial nerves, sensory and motor system, and reflexes. From each participant, a blood sample was taken to measure acetylcholinesterase activity, and liver and kidney functions. Children who have never worked in agriculture (n = 50), matched on age, education, and socioeconomic status were also studied and served as controls.

RESULTS

More neuromuscular disorders were identified in pesticide applicators than controls. A significant lower level of acetylcholinesterase was found in the applicator group compared to the controls. There was also a significant difference in hematological, renal and hepatic indices in the exposed children compared to the control children. Working more days in the current season and also working more years as a pesticide applicator were both associated with an increase in the prevalence of neuromuscular abnormalities and significant changes in the laboratory tests.

CONCLUSION

Children and adolescent pesticide applicators working in farms of Egypt are at risk of developing serious health problems similar to those of adults.

Prevalence of polysaccharide storage myopathy in horses with neuromuscular disorders

REASONS FOR PERFORMING STUDY

Controversy exists as to the prevalence of polysaccharide storage myopathy (PSSM) in breeds of horses and its impact on performance.

OBJECTIVES

To determine 1) the prevalence of PSSM in horses that presented with a neuromuscular disorder, as well as breed, sex and age distributions and clinical signs 2) effect of diagnostic criteria on prevalence, breed distribution and age of horses diagnosed with PSSM.

METHODS

Fresh frozen biopsies (n = 1426) submitted to the Neuromuscular Diagnostic Laboratory at the University of Minnesota were searched to identify horses diagnosed with PSSM. Horses with and without histological evidence of PSSM were compared. Biopsies were classified as Grade 1, containing aggregates of granular glycogen or Grade 2, containing periodic acid Schiff's (PAS) positive inclusions, traditionally resistant to amylase digestion.

RESULTS

Horses (n = 572 : 40.1%) were identified with PSSM, of which 62.9% were Quarter Horse related breeds (QHR), 11.5% Draught breeds (DB) and 8.9% Warmblood breeds (WB). Exertional rhabdomyolysis was more prevalent in QHR than DB and WB, whereas QHR were less likely to have muscle atrophy compared to DB. QHR were less likely to have gait abnormalities than DB and WB. The highest within breed prevalence of PSSM was in DB at 63/116, WB 58/111 and QHR 360/753. Exclusion of Grade 1 criteria decreased the overall prevalence of PSSM to 21.7% of biopsy submissions, and decreased the within breed prevalence in each breed category. The within breed prevalence decreased most substantially in the breeds less commonly diagnosed with PSSM, Thoroughbreds (4.5%) and Arabians (2.5%).

CONCLUSION

PSSM is a common cause of neuromuscular disease in QHR, DB and WB related breeds. Inclusion of granular glycogen as the sole diagnostic criterion may increase the sensitivity of this diagnostic test, but conversely it may decrease the specificity of the diagnosis resulting in the inclusion of horses of Thoroughbred, Arabian and other breeds.

POTENTIAL RELEVANCE

PSSM is an important differential diagnosis for QHR, WB and DB presenting with signs of rhabdomyolysis, gait abnormalities and muscle atrophy.

Childhood neurological illness in Nepal

The commonly encountered neurological disorders in Nepalese children are febrile encephalopathies, neurocysticercosis, and epilepsy, and neonatal encephalopathy, neuro-psychiatric and neuromuscular disease. Also, these children in Nepal remain one of the most vulnerable and marginalized groups in the community. Due to the lack of proper facilities some preventable and treatable neurological conditions continue to paralyze the children's physical and mental health. The alarmingly high prevalence of these neurological illnesses has high mortality and morbidity in children ultimately adding financial burden to the family, society and the country as a whole. The paucity of data and difficulties in proper collection of reliable facts further hampers to understand the actual magnitude of this problem.

[Prevalence of home mechanical ventilation in Poland]

INTRODUCTION

Home mechanical ventilation (HMV) is increasingly used in the treatment of chronic respiratory failure thanks to rapid technological development, increasing number of elderly people and extension of indications. The aim of the study was to assess: prevalence of HMV in Poland, the proportions of lung disease and neuromuscular patients using HMV and the type of interface (invasive v. non-invasive).

MATERIAL AND METHODS

The questionnaire was send to all institutions providing HMV in Poland and to regional departments of National Health System (NHS).

RESULTS

All NHS departments responded. They reported 846 HMV users, 31% of children. The prevalence of HMV in Poland was assessed as 2,2 patient per 100.000 population without striking differences between provinces. Among 39 HMV centers in Poland 12 (31%) answered. They reported 206 patients (24% of all HMV users). Proportion of ventilation mode consisted of 59% (122 pts) treated via a tracheostomy and 41% (84 pts) with non invasive ventilation (NIV). 168 patients (82%) had neuromuscular diseases (ND), majority of them muscular dystrophy - 57 patients ( 34% of ND) and amyotrophic lateral sclerosis - 39 patients (23% of ND). There were only 38 patients (18%) with lung and thoracic cage diseases: 17 with COPD and 10 with kyphoscoliosis.

CONCLUSIONS

The prevalence of HMV treatment in Poland has developed dramatically in the last decade, but is still very low comparing to other European countries, especially due to very low number of patients with lung and chest wall diseases. The prevalence of invasive mode of ventilation is extremely high. The most important factors which inhibit development of HMV in Poland are: omission of respiratory physicians in the process of qualification, lack of national guidelines, sophisticated demands for HMV providers. The awareness of the need of HMV especially in patients with respiratory failure due to obesity hypoventilation syndrome and restrictive lung diseases should be increased among chest physicians.

[Studies of segmentary and suprasegmentary levels of neuro-muscular disorders in manual workers]

The article presents results of neurophysiologic study of neuro-muscular disorders in skeletal and muscular diseases in oil industry workers. Findings are that intrasystemic relationships in nervous system of segmentary and suprasegmentary levels are involved into neuro-muscular disorders formation.

What's in the Literature?

Peripheral neuropathies are among the most common disorders seen by neuromuscular specialists. Several of the articles in this issue's review focus on diagnosis, treatment, and prognosis of disorders of peripheral nerve, including some which address important issues relating to chronic inflammatory demyelinating polyneuropathy. Motor neuron diseases continue to be somewhat disproportionately represented, likely due to the devastating nature of amyotrophic lateral sclerosis. The TAR DNA-binding protein-43 (TDP-43) story as outlined in 2 of the articles is fascinating, particularly with regard to etiopathogenesis, whereas other articles focus on epidemiology, diagnosis, treatment, and symptom management, including some insights into Kennedy disease. Myotonic dystrophy and other muscle diseases are presented with some welcome news on treatment and management.

Emergence of neuromuscular patterns during walking in toddlers with typical development and with Down syndrome

During the development of walking, toddlers with Down syndrome (DS) and typical development (TD) face challenges controlling muscles, joints, and body segments. Toddlers with DS have additional challenges including increased joint laxity and decreased muscle tone and show delayed walking onset; the underlying activity of the neuromotor system remains unclear. Here we investigated the emergence of muscle activity from walking onset through 6 months of practice in eight toddlers with DS and eight with TD. We monitored the activity of core gait muscles and motion of leg segments as toddlers walked at their self-selected speeds. At walking onset muscle bursts were frequent with inconsistent burst durations. Over time, both groups of toddlers began to activate their leg muscles by using energy-efficient strategies: decreased muscle burst frequency (Wilks' Lambda=0.364, F(12, 103.476)=4.009, p< .001) and increased muscle burst duration (Wilks' Lambda=0.346, F(12, 71.727)=2.946, p= .002). Toddlers with TD increased normalized inter-burst intervals over time but toddlers with DS decreased these interval durations. By 6 months of experience toddlers with TD showed an efficient synergy among muscles, allowing increased relaxation time between bursts. Toddlers with DS improved the rhythmicity of their muscle burst, sustaining longer bursts but timing remained inconsistent. We propose increased muscle burst duration in toddlers with DS may add control by stabilizing their lax joints. Thus, their similar yet different emergent strategy may reflect their unique biomechanical and neurophysiological constraints and represent an efficient control strategy.

Neuromuscular disorders associated with apical hypertrophic cardiomyopathy

BACKGROUND

Cardiomyopathy is a frequent manifestation of neuromuscular disorders.

AIMS AND OBJECTIVES

The aim of this study was to investigate how often apical hypertrophic cardiomyopathy (AHC) is associated with neuromuscular disorders (NMDs), which types of NMDs are associated with AHC, and if the outcome of patients with NMD and AHC is different from those with AHC but without a NMD.

METHOD

Literature review by means of a Medline (PubMed) search for the terms AHC, apical hypertrophy, NMD, myopathy, muscular dystrophy, skeletal muscle, and cardiac involvement.

RESULTS

AHC is only rarely associated with NMDs. So far,AHC has been described in patients with limb girdle muscular dystrophy, glycogen storage disease, mitochondrial disorder, metabolic myopathy, myopathy of unknown significance, eosinophilia-myalgia syndrome, or arthrogryposis multiplex congenita. The outcome of these patients was not at variance from those with AHC but without a NMD.

CONCLUSIONS

AHC is only rarely associated with NMDs, such as limb girdle muscular dystrophy, glycogen storage disease, metabolic myopathy, myopathy of unknown significance, or eosinophilia-myalgia syndrome. The rare association of NMDs with AHC might be due to absence of systematic neurologic investigations of patients with AHC and vice versa.

Postoperative respiratory complications of adenotonsillectomy for obstructive sleep apnea syndrome in older children: prevalence, risk factors, and impact on clinical outcome

OBJECTIVE

To determine the prevalence and type of respiratory complications after adenotonsillectomy for obstructive sleep apnea syndrome (OSAS) in otherwise healthy children with a completed preoperative polysomnography evaluation.

DESIGN

Retrospective analysis.

SETTING

Affiliated Hospital of Medical University, Guangzhou, Guangdong, China.

METHODS

The retrospective chart review focused on the demographic data and pertinent history, preoperative sleep evaluation, surgical and anesthetic management, and need for postoperative respiratory interventions. Improvements in quality of life after adenotonsillectomy for children with OSAS were evaluated using the OSA-18 survey (an 18-item survey on obstructive sleep apnea) completed before, and within 6 months after, surgery.

MAIN OUTCOME MEASURES

The percentage of children undergoing adenotonsillectomy to treat OSAS who experience a postoperative respiratory complication.

RESULTS

Four hundred seventy-five consecutive cases for adenotonsillectomy were identified, and 321 children met the inclusion criteria. Thirty-six cases (11.2%) had postoperative respiratory complications necessitating a medical intervention. Of the 36, 29 children (80.6%) required an oropharyngeal or nasopharyngeal airway. Twenty-five children (69.4%) experienced multiple episodes of desaturation, and 61.1% of cases (n = 22) had respiratory complications in the postanesthesia care unit. Statistic analysis showed that the risk factors for complications were young age, obesity, and high preoperative apnea-hypopnea index. Improvements in quality of life as shown by change scores (preoperative score minus postoperative score) were comparable in two groups (p > .05).

CONCLUSIONS

The most important predictors of postsurgical respiratory morbidity were young age, obesity, and the initial severity of OSAS. Surgical therapy yielded significant improvements in quality of life for children with OSAS, and the amelioration was not linked to the occurrence of postoperative respiratory complications.

[ICU-acquired neuromyopathy, delirium and sedation in intensive care unit]

ICU-acquired neuromyopathy (NMAR) and delirium are the two most frequent and severe neurological complications of intensive care medicine. Their mechanisms still remain to be elucidated. The objective of this review is to address the potential role of sedation in occurrence of these complications. There is no evidence that sedation is involved in NMARs. However, the hypothesis that muscle inactivity induced by sedation fosters NMAR is an argument to discontinue or reduce sedatives infusion whenever possible. It is also recommended not to administer propofol more than 48 h at an infusion rate above 5 mg/kg per hour in patients with systemic inflammatory response syndrome, because of the risk of propofol infusion syndrome, which includes notably rhabdomyolysis. The relationship between delirium and sedation are controversial because in most studies, patients were considered delirious though being still sedated and multivariate analysis was lacking. One study showed that lorazepam given continuously was an independent risk factor for daily transition to delirium 24 h later with a 20% increase risk of every unit dose (expressed as log(e)mg). The impact of deepness, daily interruption or titration of sedation on the prevalence of delirium has never been assessed but it seems that deep sedation has to be avoided.

The role of future longitudinal studies in ICU survivors: understanding determinants and pathophysiology of weakness and neuromuscular dysfunction

PURPOSE OF REVIEW

The goals of this review are to discuss the pathophysiology and determinants of muscle weakness and neuromuscular dysfunction after critical illness, and to offer thoughts regarding the role of future longitudinal studies in this area.

RECENT FINDINGS

While recent studies support the finding that neuromuscular dysfunction is common and important after critical illness, reversible risk factors and approaches to prevention and treatment remain unproven. Pathophysiologic studies implicate disease and treatment associated factors in the development of nerve and muscle damage during critical illness; these factors may provide targets for future studies.

SUMMARY

Additional studies with improved methodology that address epidemiology and that test interventions are needed to understand and to improve neuromuscular function after critical illness.

[Sex differences in left ventricular noncompaction in patients with and without neuromuscular disorders]

INTRODUCTION AND OBJECTIVES

Left ventricular hypertrabeculation/noncompaction (LVHT/NC) is more prevalent in men and is frequently associated with neuromuscular disorders (NMDs). The aim of this study was to assess sex differences in a) the location and extent of LVHT/NC; b) left ventricular function; c) cardiac symptoms; d) electrocardiographic findings; e) the prevalence of NMD, and f) mortality.

METHODS

Between June 1995 and September 2006, 100 patients (mean age, 53[15] years, range 14-94 years, 29 female) were diagnosed echocardiographically with LVHT/NC. All underwent cardiologic investigation and were invited to undergo a neurologic examination.

RESULTS

The neurologic examination showed normal results in 14 patients, 21 were diagnosed with a specific form of NMD, and 44 had an NMD of unknown etiology. The other 21 refused to undergo the examination. Women presented more often with LVHT/NC affecting the anterior wall (10% vs. 0%; P< .05), the inferoposterior wall (28% vs. 10%; P< .05), and the lateral wall (72% vs. 31%; P< .001). In addition, on average 2.0 ventricular regions were affected in woman compared with 1.4 in men (P< .001). In contrast, apical LVHT/NC was slightly more common in men (97% versus 86%; P=.057). No differences were observed in age, symptoms, NMD prevalence, electrocardiographic findings, or mortality.

CONCLUSIONS

In adults with LVHT/NC, there were sex differences in the location and extent of the condition. However, these did not affect clinical, neurologic, echocardiographic or electrocardiographic parameters, or prognosis. The higher prevalence of LVHT/NC in males remains unexplained.

[Types of diagnosis in the outpatient practice during the years 2006-2007]

INTRODUCTION

In recent years significant increase of children reffered to neurological consultations has been observed. Also structure of diagnosis has changed fundamentally.

AIM

The aim of the study was to reveal differentiated structure of diagnosis in children reffered to neurology outpatient clinics during 2 years of their work.

MATERIAL AND METHODS

Analysis included medical documentation of 18127 children aged 1-18 years, patients of Neurology Outpatient Clinic, Headache Outpatient Clinic and Neuromuscular Diseases Outpatient Clinic. These outpatient clinics are under supervision of Pediatric Neurology Clinic of Chair of Pediatric and Adolescent Neurology, Jagiellonian University.

RESULTS

The most numerous group consisted of children with paroxysmal events (11192, 61.74%). Diagnostics performed in outpatient clinics or during hospitalisation enabled to diagnose epilepsy in 52.42% and in remaining 9.31% other paroxysmal events: syncopes, tics, febrile convulsions, breath-holding spells, sleep disorders, night terrors, infantile masturbation and pseudoepileptic seizures. Second, in respect to number, group included children with headaches. Majority of them were reffered after exclusion of laryngological and ophtalmological causes of headaches. Specialist neuroimaging examinations, EEG examination and psychological consultations enabled to diagnose tension-type headaches in most cases, less often migraine and sporadically brain tumors were diagnosed. Another group enclose children with CNS lesions: fetopathies, congenital defects, cerebral palsy, metabolic and genetic disorders. Numerous group consisted of children with psychomotor retardation, emotional disorders, nocturnal enuresis, suspect of ADHD and scholar difficulties who needed longer development observation in order to establish final diagnosis. Group of children with neuromuscular diseases (375, 2.16%) was also differentiated. It consisted of children with muscular dystrophies and myopathies (50%), acquired peripheral mononeuropathies (post-traumatic, post-inflamatory and tunnel syndromes) and genetically determined and acquired polyneuropathies (45%) and also myasthenia and myasthenic syndromes (5%).

CONCLUSIONS

Analysis of two years work of three specialist outpatient clinics revealed differentiated causes of consultations of treated children. Paroxysmal events and necessity of initial differential diagnosis performance were main problems of their work. Fast increase in number of children with headaches, scholar difficulties and suspect of ADHD has been observed.

[Neuro-muscular apparatus state in lumbosacral radiculopathy in miners]

Based on clinical and electrophysiologic studies, the authors analysed neuro-muscular apparatus of "spinal center--periphery" axis for miners with radicular pain caused by occupational lumbosacral radiculopathy. Findings are that constantly irritated receptors in lumbar motor segment during occupational activities alter habitual motor stereotype and cause specific compensatory muscular reactions, rearrangement of motor activity in segmental apparatus.

Neuromuscular dysfunction acquired in critical illness: a systematic review

OBJECTIVE

To determine the prevalence, risk factors, and outcomes of critical illness neuromuscular abnormalities (CINMA).

DESIGN

Systematic review.

DATA SOURCES AND STUDY SELECTION

MEDLINE, EMBASE, CINAHL, and the Cochrane Library were searched for reports on adult ICU patients who were evaluated for CINMA clinically and electrophysiologically. Studies were included if they contained sufficient data to quantify the association between CINMA and relevant exposures and/or outcome variables.

MEASUREMENTS AND RESULTS

CINMA was diagnosed in 655 of 1421 [46% (95% confidence interval 43-49%)] adult ICU patients enrolled in 24 studies, all with inclusion criteria of sepsis, multi-organ failure, or prolonged mechanical ventilation. Diagnostic criteria for CINMA were not uniform, and few reports unequivocally differentiated between polyneuropathy, myopathy, and mixed types of CINMA. The risk of CINMA was associated with hyperglycemia (and inversely associated with tight glycemic control), the systemic inflammatory response syndrome, sepsis, multiple organ dysfunction, renal replacement therapy, and catecholamine administration. Across studies, there was no consistent relationship between CINMA and patient age, gender, severity of illness, or use of glucocorticoids, neuromuscular blockers, aminoglycosides, or midazolam. Unadjusted mortality was not increased in the majority of patients with CINMA, but mechanical ventilation and ICU and hospital stay were prolonged.

CONCLUSIONS

The risk of CINMA is nearly 50% in ICU patients with sepsis, multi-organ failure, or protracted mechanical ventilation. The association of CINMA with frequently cited CINMA risk factors (glucocorticoids, neuromuscular blockers) and with short-term survival is uncertain. Available data indicate glycemic control as a potential strategy to decrease CINMA risk.

[Neuromuscular complications in transplant recipients]

Neuromuscular complications in transplant recipients are common and contribute to morbidity and mortality. Complications such as acute and chronic inflammatory demyelinating polyneuropathies and toxic myopathies are related to the changes in immune modulation that occur after transplantation or result from immunosuppressive treatment toxicity. Alternatively, other complications such as myositis, myasthenia gravis, and mononeuropathy multiplex may result from a dysimmune systemic disorder such as post-transplant lymphoproliferative disorder, graft-versus-host disease or hepatitis C virus or hepatitis B virus chronic infection. Lastly, some of these complications, e.g., compression or stretch of individual nerves or plexus, are commonly seen in a postoperative setting and are not specific of patients with organ transplantation. This review focuses on the characteristic features, management, prognosis and pathophysiology of common and immune-related neuromuscular complications in organ transplant recipients.

Severe human metapneumovirus infection in hospitalized children

Human metapneumovirus is a recently discovered pathogen that causes upper and lower respiratory tract disease in children. This study describes the course of illness in hospitalized children with this infection. During a 6-month period, 11 children were diagnosed with human metapneumovirus infection by reverse transcription-polymerase chain reaction. Oxygen supplementation was required for 82% of patients. Severe disease developed in 45%, and mechanical ventilation was required. An apparent life-threatening event was the indication for hospitalization of 27% of patients infected with human metapneumovirus. Children with underlying asthma or neuromuscular disease had a prolonged hospitalization.

Critical Illness Neuromuscular Syndromes

Critical illness neuromyopathy (CINM) is the most common peripheral neuromuscular disorder encountered in the ICU. Bilateral diffuse weakness predominant in the proximal part of the limbs after improvement of the acute phase of the critical illness is highly suggestive of CINM. Although muscle and peripheral nerve often are involved in combination, muscle involvement alone increasingly is identified on electrophysiological investigation, including direct muscle stimulation. Respiratory muscles also are involved, and CINM may cause delayed weaning and prolonged MV. Besides muscle immobilization and prolonged sepsis-induced multiple organ failure, which are both strong contributors to CINM, hyperglycemia and use of corticosteroids also might have a deleterious effect on the neuromuscular system in critically ill patients.

Neuromuscular disease as the cause of late clubfoot relapses: report of 4 cases

Following correction with the Ponseti method some idiopathic clubfeet still will relapse even after six years of age. A better understanding of the cause for these late relapses will greatly help in the management of this condition. We evaluated a consecutive case-series from 1948 through December 1984 including 209 patients (321 clubfeet). Patients were treated following the Ponseti method. Initial number of casts, age at relapse, neurological evaluation, and final treatment for the late-relapses were recorded. There were 12 patients (6%) having a relapse after the seventh birthday. In 4 of these patients (6 clubfeet) a neuromuscular disease was diagnosed, representing 33% of the late relapses. These patients were initially treated with an average of 4 casts (range: 2-6) with 2 requiring an Achilles tenotomy. Patients used the brace for an average of 4 years. The average age at the relapse prior to the suspicion of neuromuscular disease was 9 years (range: 8-11 years). Two patients had family history of neuromuscular disease (myotonic dystrophy and multiple core disease). In the other two cases (Charcot-Marie-Tooth Disease type IA and myasthenia gravis) neuromuscular disease was not suspected. All four patients required an anterior tibialis transfer, three had a plantar fasciotomy, and two had peroneus longus to brevis transfers. One patient required a subsequent posterior tibialis transfer and another patient a triple arthrodesis (myotonic dystrophy). In conclusion, late relapses in patients with idiopathic clubfoot may represent the onset of a previously undiagnosed neuromuscular disease, and should be thoroughly evaluated.