Varying lengths of the cervical spinal cord of rats were irradiated with single doses of X rays. Dose-related changes in the latency for the development of paralysis, or for the presence of histological lesions in the spinal cord, indicated a dependency on the length of spine irradiated. The dose associated with a specified latency increased as the field size was reduced from 16 mm to 4 mm. A more precise indication of the importance of field size came from a determination of the ED50 values for rats developing paralysis in less than 30 weeks of irradiation or from those that showed neurological signs, or histological evidence, of irradiation damage, occurring after latent periods of greater than 30 weeks. These end-points were primarily related to white-matter necrosis and gross vascular damage respectively. For paralysis in greater than 30 weeks the ED50 increased markedly from 21.5 +/- 0.3 Gy for a 16 mm field to 50.98 +/- 2.28 Gy when a 4 mm length of cord was irradiated. For vascular lesions only a small change in ED50 value was found, from 20.0 +/- 0.5 Gy to 25.58 +/- 2.78 Gy for 16 mm and 4 mm fields respectively. At less than or equal to ED25 no evidence for a field-size effect was seen for this late lesion. These results were examined in the light of some old and some more recently analysed clinical data for radiation myelopathy. It is hoped that this will initiate other investigations in this important area of radiotherapy practice.

IntroductionNeurogenic claudication due to spinal stenosis is common in older adults. The effectiveness of conservative interventions is not known. The aim of the study is to estimate the clinical and cost-effectiveness of a physiotherapist-delivered, combined physical and psychological intervention.Methods and analysisThis is a pragmatic, multicentred, randomised controlled trial. Participants are randomised to a combined physical and psychological intervention (Better Outcomes for Older people with Spinal Trouble (BOOST) programme) or best practice advice (control). Community-dwelling adults, 65 years and over, with neurogenic claudication are identified from community and secondary care services. Recruitment is supplemented using a primary care-based cohort. Participants are registered prospectively and randomised in a 2:1 ratio (intervention:control) using a web-based service to ensure allocation concealment. The target sample size is a minimum of 402. The BOOST programme consists of an individual assessment and twelve 90 min classes, including education and discussion underpinned by cognitive behavioural techniques, exercises and walking circuit. During and after the classes, participants undertake home exercises and there are two support telephone calls to promote adherence with the exercises. Best practice advice is delivered in one to three individual sessions with a physiotherapist. The primary outcome is the Oswestry Disability Index at 12 months. Secondary outcomes include the 6 Minute Walk Test, Short Physical Performance Battery, Fear Avoidance Beliefs Questionnaire and Gait Self-Efficacy Scale. Outcomes are measured at 6 and 12 months by researchers who are masked to treatment allocation. The primary statistical analysis will be by ‘intention to treat’. There is a parallel health economic evaluation and qualitative study.Ethics and disseminationEthical approval was given on 3 March 2016 (National Research Ethics Committee number: 16/LO/0349). This protocol adheres to the Standard Protocol Items: Recommendations for Interventional Trials checklist. The results will be reported at conferences and in peer-reviewed publications using the Consolidated Standards of Reporting Trials guidelines. A plain English summary will be published on the BOOST website.Trial registration numberISRCTN12698674; Pre-results.

Medically unexplained symptoms such as headache, tiredness and stomach problems are common amongst children and research highlights the potential importance of the family environment in their development and maintenance. The present qualitative study aimed to explore how mothers make sense and manage their child's unexplained recurrent somatic symptoms. Mothers (n=13) with children with headaches, tiredness or stomach problems were interviewed. Transcripts were analysed using thematic analysis. Three main areas emerged relating to 'making sense of the symptom', 'impact of the symptom' and 'strategies for coping'. Transcending these areas were three core issues relating to managing ambiguity, authenticity and responsibility. In particular, more ambiguous symptoms were associated with making uncontrollable causal attributions that removed responsibility away from the family. Further, even though the mothers reported coping strategies that may have exacerbated their child's symptoms these were defended in ways to minimise their own potential influence on the symptom and to emphasise its authenticity. In conclusion, mothers' perceptions and behaviours may be counterproductive in the longer term but function in the more immediate term by facilitating a protective relationship with their child.

PurposeThe ‘Oxford Pain, Activity and Lifestyle’ (OPAL) Cohort is a longitudinal, prospective cohort study of adults, aged 65 years and older, living in the community which is investigating the determinants of health in later life. Our focus was on musculoskeletal pain and mobility, but the cohort is designed with flexibility to include new elements over time. This paper describes the study design, data collection and baseline characteristics of participants. We also compared the OPAL baseline characteristics with nationally representative data sources.ParticipantsWe randomly selected eligible participants from two stratified age bands (65–74 and 75 and over years). In total, 5409 individuals (42.1% of eligible participants) from 35 general practices in England agreed to participate between 2016 and 2018. The majority of participants (n=5367) also consented for research team to access their UK National Health Service (NHS) Digital and primary healthcare records.Findings to dateMean participant age was 74.9 years (range 65–100); 51.5% (n=2784/5409) were women. 94.9% of participants were white, and 28.8% lived alone. Over 83.0% reported pain in at least one body area in the previous 6 weeks. Musculoskeletal symptoms were more prevalent in women (86.4%). One-third of participants reported having one or more falls in the last year. Most participants were confident in their ability to walk outside. The characteristics of OPAL Cohort participants were broadly similar to the general population of the same age.Future plansPostal follow-up of the cohort is being undertaken at annual intervals, with data collection ongoing. Linkage to NHS hospital admission data is planned. This English prospective cohort offers a large and rich resource for research on the longitudinal associations between demographic, clinical, and social factors and health trajectories and outcomes in community-dwelling older people.