João Arthur Ehlers

An evaluation of gender, obesity, age and diabetes mellitus as risk factors for carpal tunnel syndrome

OBJECTIVES The aim of this study is to identify gender, high body mass index (BMI), age and diabetes mellitus (DM) as independent risk factors (RF) for carpal tunnel syndrome (CTS) and to analyse the strength of association of these factors, both globally and in individual subgroups. METHODS We performed a case-control study with 791 CTS cases and 981 controls. Patients were selected from those referred to nerve conduction studies and electromyography in 3 university hospitals and two private services. We calculated the odds ratio between the two groups to analyse the RF. Possible sources of bias were studied using stratified and multivariate analyses. RESULTS The mean BMI and age were greater in the case group than in the control. Female gender, BMI>30, age of 41-60 years and DM were significantly more frequent in the case group. Males tend to have a more severe CTS and DM was a significant RF for bilateral lesions. Stratified analysis showed female gender, obesity and age of 41-60 years as independent RF. DM, when stratified by BMI category, was not significantly associated with CTS. CONCLUSIONS Our study confirms that female gender, obesity and age are independent RF for CTS. DM may be a weak RF, especially among women.

Clinical features of 1039 patients with neurophysiological diagnosis of carpal tunnel syndrome

PURPOSE To describe the clinical features of patients with a neurophysiologic diagnosis of carpal tunnel syndrome (CTS) in the state of Rio Grande do Sul, Brazil. METHODS We prospectively studied 1039 patients with a neurophysiologic diagnosis of CTS in southern Brazil. All patients completed a clinicoepidemiological questionnaire which included a drawing of the arm and hand, in which they were asked to paint the areas in which paresthesia and pain occurred. In part of the sample, we also investigated the presence of clinical signs such as Tinels, Phalen, and tenar atrophy. The diagnosis of CTS was performed using a predetermined neurophysiological protocol. RESULTS A total of 1528 hands were diagnosed with CTS. The severity of CTS was mild in 42% of cases, moderate in 18% and severe in 40%. Patients had a mean age of 48.3 +/- 12.4 years old, and a ratio of 5.6 females to 1 male was observed. Symptoms restricted to the hand and wrist was observed in 51.8% of cases with paresthesia and in 18.5% of cases with pain. In 92.5% of the partially affected hands, paresthesia was present in at least one of the first three fingers, while pain affected the three first fingers in 78.8% of these hands. Pain with a distribution which did not involve the hand occurred in 18.5% of cases, while paresthesia without involvement of the hand occurred in only 1.9%. Distribution of symptoms, according to Katzs hand diagram, showed a classic pattern in 12.6% of affected hands, a pattern classified as probable CTS in 66.3%, and an unlikely CTS pattern in 4.1%. Tinels and Phalens sign were observed in 34.2 and 56.3% of the hands, respectively. CONCLUSION The clinical presentation of CTS is pleomorphic, ranging from the absence of symptoms to very severe cases. This variation probably is dependent on coexistent diseases, such as tendinitis and fibromyalgia, as well as on subjective aspects of the patients.

What symptoms are truly caused by median nerve compression in carpal tunnel syndrome

OBJECTIVE This study aims to identify the symptoms, signs and distributions which are associated with neurophysiological carpal tunnel syndrome (N-CTS), defined by the finding of a median nerve lesion at the wrist through neurophysiologic studies, and to compare them with those of patients with sensory or motor complaints in the upper limbs whose electrophysiologic investigation did not show evidence of this syndrome. METHODS A cross-sectional study was performed, with prospective gathering of data, following a predetermined protocol. We included all patients older than 12 years who were referred for nerve conduction studies and electromyography of at least one of the upper limbs between August 2001 and January 2003. The patients answered a clinicoepidemiologic questionnaire and painted the areas in which they felt pain and those in which they felt paresthesia, and were also examined to test for classical signs CTS. RESULTS A neurophysiological diagnosis of CTS was reached in 1549 upper limbs (39%). Approximately 6% of the upper limbs with N-CTS and 16% of those without median nerve lesion do not have any hand or wrist symptoms (P<0.001). Paresthesia, pain, hand weakness and cramps were the symptoms statistically associated to N-CTS, with paresthesia being the one with the greatest power of association. This is usually felt in median innervations territory, and is frequently extended to the whole hand, but without association with N-CTS when felt in proximal region. CONCLUSIONS One concludes that the most characteristic manifestation of carpal tunnel syndrome (CTS) is paresthesia. Pain also occurs very frequently but it is less specific, and weakness, meanwhile, seems to have a low frequency. We believe that the variability in the clinical presentation of CTS is largely due to the presence of associated diseases and our results provide information which could help to better define the clinical criteria used in the diagnosis of this syndrome.

Clozapine, but not typical antipsychotics, correct P50 suppression deficit in patients with schizophrenia.

OBJECTIVE To find out if there is a difference in P50 suppression between patients using typical antipsychotic drugs and those using clozapine, as well as to confirm the findings of abnormal P50 suppression in patients with schizophrenia, when compared to healthy volunteers. METHODS Fifty patients with schizophrenia and 25 healthy volunteers were divided into 3 groups: group 1 - patients using typical antipsychotics; group 2 - patients using clozapine; group 3 - controls. Before the examination, all patients were interviewed by a psychiatrist using the Brief Psychiatry Rating Scale (BPRS). RESULTS The average S2/S1 ratio was 0.82+/-0.45 in group 1, 0.57+/-0.41 in group 2, and 0.44+/-0.27 in group 3 (P=0.003). Statistical analysis showed a significant difference when the results of group 1 were compared to those of groups 2 (P=0.045) and 3 (P=0.001). There was no significant difference between groups 2 and 3 (P=0.182). There was a significant difference in the S1-S2 difference only between groups 1 and 3 (P=0.007), but a non-significant trend towards a similar difference was found between groups 1 and 2 (P=0.067). There was no correlation between the BPRS values and any P50 parameter. CONCLUSIONS The suppression of P50 among patients using clozapine was significantly greater than that obtained in patients using typical antipsychotics. SIGNIFICANCE This study confirms, in a more evident way, the improvement of the suppression of P50 potential in schizophrenics using clozapine. Additionally, it discusses the physiopathological mechanism involved.

Prediction of the neurophysiological diagnosis of carpal tunnel syndrome from the demographic and clinical data

OBJECTIVE To use demographic and clinical data to identify the clinical pattern that best predicts the diagnosis of carpal tunnel syndrome (CTS), as defined by neurophysiologic studies. METHODS A diagnostic cross-sectional study in 2535 consecutive patients (3907 upper limbs) older than 12 years old who were referred for nerve conduction studies in the upper limbs between August 2001 and January 2003 in 3 university hospitals and 2 private neurophysiology services in the state of Rio Grande do Sul, Brazil. RESULTS A neurophysiologic diagnosis of CTS was established in 39.1% of these upper limbs. The presence of paresthesias or pain at least 2 of the first 4 digits in association with one of the following: female gender, symptoms worsening at night or on awakening, an BMI > or =30, thenar atrophy, or other sign (Tinels, Phalens, or Reversed Phalens signs); were the best pattern associated with the diagnosis. CONCLUSIONS We have found that the clinical picture alone does not seem sufficient, in majority of the population, to correctly predict the diagnosis of CTS, as defined by median nerve neuropathy at the carpal tunnel. We believe that a compressive lesion of the median nerve at the carpal tunnel can be present both in patients with no typical symptoms of CTS (including asymptomatic individuals) and in patients in which neurophysiologic studies are negative. SIGNIFICANCE Further studies separating patients into these groups will allow us to identify the long-term prognosis as well as the ideal therapeutic approach for each of these clinical situations.

Hyperhidrosis in Parkinson's disease

We studied the sudomotor skin response (SSR) in patients with Parkinsons disease with and without symptomatic hyperhidrosis. The study was carried out in 13 patients who complained of excessive sweating and in 37 patients who did not have excessive sweating. Patients were matched for age, sex, degree of impairment, duration of the disease, and number and severity of autonomic disturbances. Excessive sweating involved mainly the face, head, and trunk. The SSR was recorded from the palm of the hands to electrical stimulation of the median nerve at the wrist. We analyzed onset latency, peak to peak amplitude, and waveform. Patients with hyperhidrosis had more often absent responses (χ2 = 5.292; P = 0.021), their responses were of lower mean amplitude (analysis of variance [ANOVA]; F[2,101] = 11.678; P < 0.001), and they had a reduced number of responses with a predominantly negative component (χ2 = 8.493; P = 0.004) than patients who did not complain of sweating disturbances. Our results indicate that excessive sweating in Parkinsons disease concurs with decreased activation of sweat glands in the palms of the hands and suggests that axial hyperhidrosis could be a compensatory phenomenon for reduced sympathetic function in the extremities.

Seasonal distribution and demographical characteristics of carpal tunnel syndrome in 1039 patients

OBJECTIVE To describe the demographic characteristics of gender, age, and presence of repetitive movements, intake of alcohol and non-steroid anti-inflammatories (NSAI), medical specialties that referred patients to nerve conduction studies and electromyography (NCS-EMG), school attainment, and seasonal distribution in patients with a neurophysiological diagnosis of carpal tunnel syndrome (CTS) in the State of Rio Grande do Sul, Brazil. METHOD A series of 1039 patients (1549 hands) with neurophysiologically defined CTS was studied. Patients were referred for NCS-EMG in 3 universities and 2 private services, from August 2001 to January 2003. All patients completed a questionnaire containing demographic information. The diagnosis of CTS was established following a pre-established protocol, with defined diagnostic criteria. RESULTS Around one fourth of patients had already performed NCS-EMG; the greatest frequency of CTS was observed in women (5.6:1) and in patients above the age of 40. Most patients reported performing repetitive movements in their daily routine (69.7%); 12.9% reported use of NSAI and 14.9% regular intake of alcoholic beverages. A greater frequency of CTS was observed in the months of July and August, when compared to the other months of the year. Around 2/3 of the study population had completed at least secondary school. Most requests of nerve conduction studies did not provide a diagnostic hypothesis (59.9%) and neurophysiologic studies were requested mostly by traumatology/orthopedics (71.1%). CONCLUSION We have concluded that, in our environment, CTS shows some demographical characteristics that are similar to what the literature describes. Also, we have found that most of our sample concluded at least secondary school, and was referred to neurophysiologic studies by orthopedists. To be pointed out is the seasonal distribution of CTS, which demonstrates a significant association with winter months.

Visual-evoked potentials : Assessment of retrobulbar and peribulbar anesthesia

Purpose: To assess the effects of retrobulbar and peribulbar anesthesia on nerve function as detected by visual‐evoked potentials (VEPs). Setting: University hospital in southern Brazil. Methods: In a prospective study, 7 patients had peribulbar anesthesia and 9 had retrobulbar anesthesia for extracapsular cataract extraction. Visual‐evoked potentials with pattern reversal and flash stimulation were performed at least 1 month before and 1 month after surgery. Study participants did not have ocular pathology other than cataract. The Lens Classification System III was used to grade the opacities before surgery. Results: No significant difference was found between preoperative and postoperative evaluations in VEP flash and pattern‐reversal amplitude and latency in either group (P > .05). Postoperative amplitude and latency was not significantly different between the peribulbar and retrobulbar groups. Two cases in the peribulbar group had altered wave morphology without clinical manifestation postoperatively. All patients had a final best spectacle‐corrected visual acuity of 20/20. Conclusion: Block anesthetic procedures were safely used in cataract surgery, with no clinical sequelae to the optic nerve.

Congenital Intramedullary Tumor With Neonatal Manifestations

The authors report on a 45-day-old boy with a congenital intramedullary tumor with clinical manifestations since birth. Neurologic examination disclosed severe bilateral lower-limb hypotonia and diplegia, with exacerbated deep tendon reflexes and clonus associated with severe pain at manipulation. Further evaluation of this patient included screening for infections, computed tomographic scan, myelography, and somatosensory evoked potentials. The definite diagnosis was a solid holocord astrocytoma. This report discusses a rare disorder in the neonatal period and makes other medical practitioners aware of this diagnosis. Previously published literature is also reviewed. (J Child Neurol 1999; 14:467-469).

Paralisia bulbar progressiva juvenil doença de Fazio-Londe: relato de caso

Progressive bulbar palsy, also called Fazio -Londe disease, is characterized by progressive impairment of cranial nerves in children. It was first reported by Fazio in 1892 and until now only 30 cases have been published in the literature. Both sexes can be affected and clinical course can be divided on early (< 6 years age, predominance of respiratory symptoms) and late course (6-20 years of age, predominance of motor symptoms on superior limbs). We report a 4 years old boy that started with intense stridor and respiratory distress, initially being diagnosed as an acute asthma attack. Clinical signs worsened and 12 months latter he already had impairment of cranial nerves V, VII, VIII, IX and X confirmed by clinical examination and neurophysiological evaluation.