The median frequency of the surface EMG power spectrum in relation to motor unit firing and action potential properties

Three components determine the power spectrum of the surface EMG signal: the auto- and cross-power spectra of the firing processes and the power spectra of the motor unit action potential (MUAP). To clarify the relative contribution of these components to the median frequency (MF) of the power spectrum, a stochastic simulation model was used in which most input parameters [e.g., MUAP peak-peak time (PPT), mean interpulse interval time, and synchronization parameters] were described in terms of distribution functions. Simulation clearly predicts that MF is especially sensitive to variations in MUAP shape, the MUAP PPT, and synchronization. The influence of the firing process parameters was predicted to be marginal. To obtain values for the MUAP parameters, a needle-triggered averaging technique was used to gather surface MUAPs from the m. biceps brachii. With use of these MUAPs as input for the model, it was found that intrasubject variability of MF is caused by variations in both MUAP PPT and MUAP shape, whereas intersubject variability in MF is caused primarily by variations in PPT

Cost effectiveness of physiotherapy, manual therapy, and general practitioner care for neck pain: economic evaluation alongside a randomised controlled trial

OBJECTIVE: To evaluate the cost effectiveness of physiotherapy, manual therapy, and care by a general practitioner for patients with neck pain. DESIGN: Economic evaluation alongside a randomised controlled trial. SETTING: Primary care. PARTICIPANTS: 183 patients with neck pain for at least two weeks recruited by 42 general practitioners and randomly allocated to manual therapy (n=60, spinal mobilisation), physiotherapy (n=59, mainly exercise), or general practitioner care (n=64, counselling, education, and drugs). MAIN OUTCOME MEASURES: Clinical outcomes were perceived recovery, intensity of pain, functional disability, and quality of life. Direct and indirect costs were measured by means of cost diaries that were kept by patients for one year. Differences in mean costs between groups, cost effectiveness, and cost utility ratios were evaluated by applying non-parametric bootstrapping techniques. RESULTS: The manual therapy group showed a faster improvement than the physiotherapy group and the general practitioner care group up to 26 weeks, but differences were negligible by follow up at 52 weeks. The total costs of manual therapy (447 euro; 273 pounds sterling; 402 dollars) were around one third of the costs of physiotherapy (1297 euro) and general practitioner care (1379 euro). These differences were significant: P <0.01 for manual therapy versus physiotherapy and manual therapy versus general practitioner care and P=0.55 for general practitioner care versus physiotherapy. The cost effectiveness ratios and the cost utility ratios showed that manual therapy was less costly and more effective than physiotherapy or general practitioner care. CONCLUSIONS: Manual therapy (spinal mobilisation) is more effective and less costly for treating neck pain than physiotherapy or care by a general practitione

ESTRO/ACROP IORT recommendations for intraoperative radiation therapy in primary locally advanced rectal cancer

Summary: Carcinoma of the rectum is a heterogeneous disease. The clinical spectrum identifies a subset of patients with locally advanced tumours that are close to or involve adjoining structures, such as the sacrum, pelvic sidewalls, prostate or bladder. Within this group of patients categorized as ‘‘locally advanced”, there is also variability in the extent of disease with no uniform definition of resectability. A practice-oriented definition of a locally advanced tumour is a tumour that cannot be resected without leaving microscopic or gross residual disease at the resection site. Since these patients do poorly with surgery alone, irradiation and chemotherapy have been added to improve the outcome. Intraoperative irradiation (IORT) is a component of local treatment intensification with favourable results in this subgroup of patients. International guidelines (National Comprehensive Cancer Network (NCCN) guidelines) currently recommend the use of IORT for rectal cancer resectable with very close or positive margins, especially for T4 and recurrent cancers. We report the ESTRO-ACROP (European Society for Radiotherapy and Oncology - Advisory Committee on Radiation Oncology Practice) recommendations for performing IORT in primary locally advanced rectal cancer

Fourth mRNA COVID-19 vaccination in immunocompromised patients with haematological malignancies (COBRA KAI): a cohort study

Background Patients with haematological malignancies have impaired antibody responses to SARS-CoV-2 vaccination. We aimed to investigate whether a fourth mRNA COVID-19 vaccination improved antibody quantity and quality. Methods In this cohort study, conducted at 5 sites in the Netherlands, we compared antibody concentrations 28 days after 4 mRNA vaccinations (3-dose primary series plus 1 booster vaccination) in SARS-CoV-2 naive, immunocompromised patients with haematological malignancies to those obtained by age-matched, healthy individuals who had received the standard primary 2-dose mRNA vaccination schedule followed by a first booster mRNA vaccination. Prior to and 4 weeks after each vaccination, peripheral blood samples and data on demographic parameters and medical history were collected. Concentrations of antibodies that bind spike 1 (S1) and nucleocapsid (N) protein of SARS-CoV-2 were quantified in binding antibody units (BAU) per mL according to the WHO International Standard for COVID-19 serological tests. Seroconversion was defined as an S1 IgG concentration > 10 BAU/mL and a previous SARS-CoV-2 infection as N IgG > 14.3 BAU/mL. Antibody neutralising activity was tested using lentiviral-based pseudoviruses expressing spike protein of SARS-CoV-2 wildtype (D614G), Omicron BA.1, and Omicron BA.4/5 variants. This study is registered with EudraCT, number 2021-001072-41. Findings Between March 24, 2021 and May 4, 2021, 723 patients with haematological diseases were enrolled, of which 414 fulfilled the inclusion criteria for the current analysis. Although S1 IgG concentrations in patients significantly improved after the fourth dose, they remained significantly lower compared to those obtained by 58 age-matched healthy individuals after their first booster (third) vaccination. The rise in neutralising antibody concentration was most prominent in patients with a recovering B cell compartment, although potent responses were also observed in patients with persistent immunodeficiencies. 19% of patients never seroconverted, despite 4 vaccinations. Patients who received their first 2 vaccinations when they were B cell depleted and the third and fourth vaccination during B cell recovery demonstrated similar antibody induction dynamics as patients with normal B cell numbers during the first 2 vaccinations. However, the neutralising capacity of these antibodies was significantly better than that of patients with normal B cell numbers after two vaccinations. Interpretation A fourth mRNA COVID-19 vaccination improved S1 IgG concentrations in the majority of patients with a haematological malignancy. Vaccination during B cell depletion may pave the way for better quality of antibody responses after B cell reconstitution