Title: The British Orthopaedic SCFE Surgery Study for Severe Stable Slips (The Big BOSS Study): A multi-centre prospective randomised superiority trial of an acute deformity correction versus pinning in-situ for severe stable SCFE in children
Funder: Department of Health and Social Care

Abstract: Written by the PPI co-investigators:_x000D_ _x000D_ A slipped capital femoral epiphysis (or SCFE) is a rare condition but one of the most important paediatric and adolescent hip disorders. SCFE is the most common reason for hip replacement surgery in both adolescence and early adulthood, and rates of this condition are increasing. A survey of almost 100 surgeons from the British Society Children’s Orthopaedic Surgery have prioritised this as requiring urgent research._x000D_ _x000D_ The simplest explanation of the disease is to consider SCFE like a ball of ice cream (the top of the hip) on an ice cream cone (the femur bone). The ice cream ball could melt and slip a little (minor slip), or slip a lot (severe slip) or could just come loose from the cone completely (unstable slip). Unstable slips are particularly feared as the blood supply to the hip can be torn as the hip moves, which may cause the whole hip to die (like the ice cream falling on the floor). _x000D_ _x000D_ The treatment of SCFE always involves surgery to stabilise the slip, though the type of surgery depends on the nature of the condition. In mild slips surgery involves inserting a screw using keyhole surgery, to stop the hip slipping any more. For more severe slips, the first treatment option is inserting a screw through keyhole surgery, but accepting the shape of the hip has changed which may cause problems with walking and may risk later osteoarthritis. The second option is to correct the slip through major surgery, which could make the hip unstable and carries a risk that the hip bone may disintegrate causing disability. _x000D_ _x000D_ Uncertainty exists around which surgery offers the best outcome due to the lack of high quality evidence. _x000D_ _x000D_ Aims_x000D_ This study will compare major surgery to correct the hip, to keyhole surgery without any correction. The important finding will be how well the young people can function (i.e. walk/run/play/participate in sport) 2 years after the condition was first identified._x000D_ _x000D_ Methods_x000D_ Children aged 8 years and above with a Stable Severe SCFE will be asked to join. _x000D_ _x000D_ Those who agree will be split into two groups, using a computer to fairly select one of the two treatments at random. _x000D_ _x000D_ All children will be followed-up for two-years to monitor function. The study will also ask about pain, if the young person needed any more surgery, any complications and the number of hospital visits. The study will need 192 children in total._x000D_ _x000D_ How have families and the public been involved?_x000D_ Families have been involved over several years through a preceding study – the BOSS Study. Emma Morley has been a keen parent co-investigator throughout the last 5-years. Milli Browne was a participant in the BOSS Study, following a Severe Stable SCFE. Both are keen co-investigators. The research question and approach, has been discussed with children and families affected by the condition and the Young Person’s and Parent's Advisory Groups in Liverpool. It was felt that more major surgery necessitated a big improvement in function to justify. _x000D_ _x000D_ How will this research make a difference?_x000D_ At the end of the study, it will allow hospitals to know the best treatment. To make sure people learn about our findings, the doctors who help with this study will talk to other doctors, and other people in the NHS who write national guidelines. Milli and Emma will help deliver the message to parents and children, and will be invited to share their experience and the results with medical professionals.

Lay abstract: Slipped Capital Femoral Epiphysis (SCFE) is the most common hip disease of adolescence, akin to a hip fracture. There is strong evidence that childhood obesity is the major cause. In the short-term it requires surgery to stabilise the hip, and typically results in deformity. In the long-term it accelerates the development of osteoarthritis and disability, often necessitating hip replacement in early adulthood. Patient’s with severe deformity face particular uncertainty. _x000D_ _x000D_ Traditionally, the approach to managing severe SCFE is to stabilise the hip with minor surgery, albeit accepting the deformity that may cause pain and arthritis. However, the newer ‘major’ surgical techniques of ‘open reduction’ immediately restores normal anatomy, though this comes with the notable risk of complete collapse of the femoral head with immediate pain and disability._x000D_ _x000D_ There is growing uncertainty regarding the optimal surgical approach, i.e. traditional ‘minor surgery’ vs. newer ‘major surgery’, which has driven members of the British Society of Children’s Orthopedic Surgery to make this as their top research priority. _x000D_ _x000D_ We propose a multi-centre prospective randomised superiority trial of acute deformity correction versus pinning-in-situ for stable severely SCFE in children aged 8 years and above. We will use well-established networks of children’s orthopaedic surgeons engaged in research; many of whom have contributed to a preceding study in this disease area. _x000D_ _x000D_ The primary outcome is the Patient Reported Outcomes Measurement Information System Mobility Score for Children (PROMIS Mobility)._x000D_ _x000D_ The proposed project is a two-phased study. An internal pilot will confirm the expected rate of recruitment to this trial, and will take place at 30 centres over 12 months. The pilot will determine the number of eligible and recruited patients in centres, optimise electronic data collection procedures and enable qualitative work. _x000D_ _x000D_ The pilot will seek to recruit >0.2 patients/ month/ centre, and has clear stop/go criteria. The main trial will continue to recruit from these centres. With consent, a research associate will collect baseline demographic data, PROMIS Mobility, Wong Baker Faces Pain Score, EQ-5DY, complications, cost-effectiveness and satisfaction._x000D_ _x000D_ A randomisation sequence, using a minimisation algorithm with stratification factors: age group (8-10 years, 11-16 years) and bilateral disease (presence or absence) will be produced by the trial statistician. Patients will be randomly allocated (1:1) to interventions._x000D_ _x000D_ Follow-up will occur at 8 weeks during routine clinical care, and thereafter electronically (by email or text message) or by telephone. Outcomes will be collected at 8 weeks, 3 months, 6 months, 1 year and 2 years (Primary outcome time-point). Electronic follow-up will be administered centrally. _x000D_ _x000D_ An embedded qualitative study will occur throughout the trial to inform the development of trial materials and to identify barriers and facilitators to recruitment. This information will be used to develop practical strategies that can be implemented in the main trial to improve recruitment and enhance acceptability of the trial._x000D_ _x000D_ Consent will be sought from participants to allow potential future follow up through efficient means using linkage to routine healthcare databases, such as the hospital episode statistics, National Joint Registry of England and Wales, and joint registries in Scotland and Northern Ireland.

Research activity codes: 6.4 SURGERY
Health categories: MUSCULOSKELETAL