Richard Carey Smith is an orthopaedic oncology surgeon with fellowship training in the UK, USA, Australia and Canada, and has worked in Zambia, Zimbabwe and Papa New Guinea. David Wood is head of the University Department of Orthopaedics in Perth, Western Australia. He did his masters in Africa, and first experienced Papa New Guinea on his medical elective, starting a lifelong commitment to medical aid work there.

The October 2012 Children’s orthopaedics Roundup. 360. looks at: magnetic growing rods and scoliosis correction; maintaining alignment after manipulation of a radial shaft fracture; Glaswegian children and swellings of obscure origin; long-term outcome of femoral derotation osteotomy in cerebral palsy; lower-leg fractures and compartment syndrome in children; fractures of the radial neck in children; management of the paediatric Monteggia fracture; and missing the dislocated hip in Western Australia

This is the second of a series of reviews of registries. This review looks specifically at worldwide registry data that have been collected on knee arthroplasty, what we have learned from their reports, and what the limitations are as to what we currently know.