Outcomes of Displaced Distal tibial fractures - Surgery Or Casts in KidS (ODD SOCKS). A multi-centre prospective randomized superiority trial of conservative versus surgical treatment for displaced distal tibial fractures in children

Fractures in children are complicated by the presence of growth plates (physes). Fractures of the distal tibial growth plate are estimated to account for 40% of growth plate injuries in children. The growth plate at the distal tibia contributes approximately 3-5mm of length to the leg per year, accounting for 45% of tibial growth and 20% of overall leg length. If this growth plate is damaged during a fracture it may heal with a solid block of bone from which no growth can occur. In its simplest form, this can cause a difference in the length of the leg compared to the unaffected side or, if part of the growth plate is damaged, then this can cause progressive angulation (deformity) as the child grows. There is uncertainty amongst surgeons as to whether realigning the bone perfectly is beneficial in preventing growth-related complications– with evidence of mixed practice throughout the UK. Realignment typically involves surgery with general anaesthesia to restore the anatomy. This may involve simple manipulation, or may involve open surgery with fixation to hold the bone in position (i.e. metal screws or wires). Surgeons and families are keen to know whether surgery is superior to no surgery, or if the risks associated with surgery are not justified. Current evidence within the literature is contradictory and of poor methodological quality, however evidence suggests that 40% of patients develop problems associated with growth. We propose a multi-centre prospective randomised superiority trial of surgery (with or without fixation) versus non-operative care for children with a displaced (Salter Harris II) fracture of the distal tibia, amongst children aged 8 – 15 years old. We will use well- established networks of children’s orthopaedic surgeons engaged in research; many of whom are already contributing to studies in paediatric orthopaedic trauma. The primary outcome is the Patient Reported Outcomes Measurement Information System Mobility Score for Children (PROMIS Mobility). 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 9 months. The pilot will determine the number of eligible and recruited patients in centres AND optimise electronic data collection procedures. The pilot will seek to recruit >0.42 patients/ centre month, and has clear stop/go criteria. The main trial will continue to recruit from these centres. A research associate will collect baseline demographic data, PROMIS Mobility, Wong Baker Faces Pain Score, EQ-5DY, leg length, angular deformity, appearance of deformity, need for subsequent surgery, patient satisfaction, educational participation, complications and cost-effectiveness. A randomisation sequence, using a minimisation algorithm with stratification factors: centre, age group (8-12 years, 11-15 years) and severity of deformity will be produced by the trial statistician. Patients will be randomly allocated (1:1) to interventions. Follow-up will occur at 6 weeks, 3 months, 6 months, 1 year and 2 years (primary outcome time-point). Electronic follow-up using patient reported outcomes will be administered centrally. 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.