Alteration of cortical but not spinal inhibitory circuits in idiopathic scoliosis.

Background: The pathogenesis of adolescent idiopathic scoliosis (AIS), including the role of brain and spinal inhibitory circuits, is still poorly elucidated. The aim of this study was to identify which central inhibitory mechanisms are involved in the pathogenesis of AIS.Design: A prospective neurophysiological study, using a battery of neurophysiological tests, such as cutaneous (CuSP) and cortical (CoSP) silent periods, motor evoked potentials (MEP) and paired-pulse transcranial magnetic stimulation (ppTMS).Settings: Neurophysiological laboratory.Participants: Sixteen patients with AIS (14 females, median age 14.4) and healthy controls.Outcome measures: MEPs were obtained after transcranial magnetic stimulation (TMS) and recorded from the abductor pollicis muscle (APB). ppTMS was obtained at interval ratios (ISI) of 1, 2, 3, 6, 10, 15 and 20 ms. The cortical silent period (CoSP) was recorded from the APB. The cutaneous silent period (CuSP) was measured after painful stimuli delivered to the thumb while the subjects maintained voluntary contraction of the intrinsic hand muscles. The data were analyzed and compared with those from healthy subjects.Results: The CoSP duration was significantly prolonged in AIS patients. A significantly higher amplitude of ppTMS for ISI was found in all AIS patients, without remarkable left-right side differences. No significant difference in MEP latency or amplitude nor in the CuSP duration was obtained.Conclusion: Our observation demonstrates evidence of central nervous system involvement in adolescent idiopathic scoliosis (AIS). Lower intracortical inhibition, higher motor cortex excitability, and preserved spinal inhibitory circuits are the main findings of this study. A possible explanation of these changes could be attributed to impaired sensorimotor integration predominantly at the cortical level.

Spontaneous spinal epidural haematoma: management and main risk factors in era of anticoagulant / antiplatelet treatment.

AIM OF THE STUDY: Spontaneous spinal epidural haematomas (SSEH) are rare nosological units wherein acute collections of blood develop in the spinal canal. SSEH are usually manifested by sudden severe back pain accompanied by the development of neurological symptoms. In this study, we retrospectively describe management and the main risk factors of SSEH in a series of 14 cases. MATERIAL AND METHODS: Between 2010 and 2019, we examined 14 patients (age range 17-89 years, 10 women) diagnosed with SSEH. Eight cases were patients using anticoagulant therapies (six warfarin, one dabigatran, one apixaban) and two others were using ASA of 100 mg/day. The exact localisation and extent of changes was determined from acute magnetic resonance imaging. Three people using warfarin had INR values higher than 3.0 at the time of their diagnosis. RESULTS: Ten patients (71%) were taking oral anticoagulants or antiplatelet agents. In seven patients, SSEH were localised in the lower cervical/thoracic spine. Ten patients (71%) had arterial hypertension. Six patients underwent acute surgery due to rapidly developing spinal cord compression. Eight patients (57%) with slight or mild neurological symptoms were successfully managed without surgery. CONCLUSIONS: SSEH should be suspected in any patient receiving anticoagulant/antiplatelet agents who complains of sudden, severe back pain accompanied by neurological symptoms. SSEH is mostly localised in the lower cervical/thoracic spine. Arterial hypertension appears to be a risk factor of SSEH. Early decompression is an important therapeutic approach; in cases with minor neurological deficits, conservative treatment may be chosen.

Estimation of p,p'-DDT degradation in soil by modeling and constraining hydrological and biogeochemical controls.

Despite not being used for decades in most countries, DDT remains ubiquitous in soils due to its persistence and intense past usage. Because of this it is still a pollutant of high global concern. Assessing long term dissipation of DDT from this reservoir is fundamental to understand future environmental and human exposure. Despite a large research effort, key properties controlling fate in soil (in particular, the degradation half-life (τsoil)) are far from being fully quantified. This paper describes a case study in a large central European catchment where hundreds of measurements of p,p'-DDT concentrations in air, soil, river water and sediment are available for the last two decades. The goal was to deliver an integrated estimation of τsoil by constraining a state-of-the-art hydrobiogeochemical-multimedia fate model of the catchment against the full body of empirical data available for this area. The INCA-Contaminants model was used for this scope. Good predictive performance against an (external) dataset of water and sediment concentrations was achieved with partitioning properties taken from the literature and τsoil estimates obtained from forcing the model against empirical historical data of p,p'-DDT in the catchment multicompartments. This approach allowed estimation of p,p'-DDT degradation in soil after taking adequate consideration of losses due to runoff and volatilization. Estimated τsoil ranged over 3000-3800 days. Degradation was the most important loss process, accounting on a yearly basis for more than 90% of the total dissipation. The total dissipation flux from the catchment soils was one order of magnitude higher than the total current atmospheric input estimated from atmospheric concentrations, suggesting that the bulk of p,p'-DDT currently being remobilized or lost is essentially that accumulated over two decades ago.

Intrathecal Baclofen in Spinal Spasticity: Frequency and Severity of Withdrawal Syndrome.

BACKGROUND: Intrathecal baclofen (ITB) delivered by programmable pump devices represents an important modality for long-term treatment of severe spinal spasticity. OBJECTIVE: One of the serious adverse events is a withdrawal syndrome after sudden interruption of ITB delivery. In this study, we analyzed the frequency and severity of this complication. Treatment recommendations follow. STUDY DESIGN: Case study. SETTING: Academic medical center. METHODS: A total of 54 ITB pumps were successfully implanted in 39 patients with severe intractable spasticity (24 with spinal cord injury, 15 with multiple sclerosis, 24 men, age range 21-59 years). RESULTS: Eight patients developed a withdrawal syndrome on total a daily dose of ITB between 90-420 µg/day. Seven patients had catheter-related complications. In one patient, pump failure was observed due to its corrosion. Within the group, baclofen withdrawal syndrome occurred once in 20.1 pump-years counted out of 160.4 pump-years of ITB treatment. LIMITATIONS: Small sample size. CONCLUSIONS: ITB withdrawal syndrome is a rare but life-threatening event and prompt diagnosis before treatment initiation is critical. The reported events were mostly mild due to the acute treatment regime and probably due to a lower dose of ITB. A prerequisite for successful ITB treatment is a deep knowledge of complications and their prompt management in the hands of a multidisciplinary team in specialized centers.