Extendable proximal femoral replacements(PFR) are used in children with bone tumours in proximity to the proximal femoral physis, previously treated by hip disarticulation. Long-axis growth is preserved, allowing limb salvage. Since 1986, survival outcomes after limb salvage and amputation have been known to be equal. Retrospective review of all patients <16years undergoing extendable PFR at Royal National Orthopaedic Hospital (UK) between 04/1996 and 01/2006, recording complications, failures, procedures undertaken and patient outcomes.Background
Method
Extendable partial femoral replacements (EPFR) permit limb salvage in children with bone tumours in proximity to the physis. Older designs were extended through large incisions or minimally invasive surgery. Modern EPFR are lengthened non-invasively. Lengthening improves functional score (Futani, 2006) but has been associated with complications including infection (Jeys, 2005). This study is the first to look specifically at the relationship between EPFR lengthening and complications. Retrospective review of 51 paediatric (<16 years) oncology patients undergoing primary (1 °) EPFR (minimally/noninvasive) between 06/1994 and 01/2006. Exclusions: 1 patient with 5cm extension without medical intervention and 5 patients with incomplete data.Background
Method
The development of extendable prostheses has permitted limb salvage surgery in paediatric patients with bone tumours in proximity to the physis. Prostheses are extended to offset limb length discrepancy as the child grows. Aseptic loosening (AL) is a recognised complication. The implant stem must fit the narrow paediatric medullary canal and remain fixed while withstanding growth and increasing physical demands. Novel designs incorporate a hydroxyapatite (HA) coated collar that manufacturers claim improves bony ongrowth and stability, providing even stress distribution in stem and shoulder regions and providing a bone-implant seal, resulting in decreased AL and prolonged survival. This study aims to assess whether there is a relationship between bony ongrowth onto a HA collar and AL. Hypothesis: Bone ongrowth onto the HA collar of extendable prostheses is associated with more stable fixation and less AL despite patient growth. Retrospective review of 51 primary partial femoral extendable prostheses implanted over 12 years from 1994–2006 (followed up to death at a mean of 2.5±2.2 years or last clinical encounter at a mean of 8.6 years) and 24 subsequent revisions, to ascertain failure rate and mode, together with a cohort study reviewing bony ongrowth onto the HA coated collar in 10 loose and 13 well fixed partial femoral, humeral and tibial implants. Patient growth was measured as a change in bone:implant-width ratio.Background/Aims
Methods
