The relationship between the number of modularities and serum ions across different designs of metal on metal hip arthroplasty

Abstract

s / International Journal of Surgery 12 (2014) S13eS117 S61 Results: The mechanism of injury was either due to a rugby tackle or fall from a bicycle. The majority of our cohort was male 86% with mean age 38 at time of surgery. All patients received physiotherapy sessions and been followed for 3-6 months. Post-operatively there were no significant difference in mean CC between operated and normal contralateral side. (12.2 vs 11.9 mm) (P<0.5). The median of quick DASH and ASES scores were 15.9 & 79.99 respectively. All the patients were satisfied with no complications recorded. Conclusions: Arthroscopic dog bone tight rope fixation of the ACJ is showing significant promise with minimal scarring and promising functional outcomes, good radiological outcomes, short post-operative stays and a low rate of complications. 0727: THE RELATIONSHIP BETWEEN THE NUMBER OF MODULARITIES AND SERUM IONS ACROSS DIFFERENT DESIGNS OF METAL ON METAL HIP ARTHROPLASTY Samer Mahmoud , Salam Ismael , Ibrahim Malek , D. woodnut , Alun Jones , Steve Jones . Royal National Orthopaedic Hospital, London, UK; University Hospital of Wales, Cardiff, UK; Morriston Hospital, Swansea, UK; 4 St George Hospital, London, UK. Introduction: To assess the relationship between serum ion levels and modularity across different metal on metal (MOM) arthroplasty designs. Methods: A cohort of 616 metal on metal hip replacement patients with similar bearing materials divided based on modularity design (number of articulating surfaces) into 4 groups: resurfacing BHR, Midhead replacements BMHR, Non-cemented stem MOM Hip replacement and the R3 with 3 bearing surfaces (115, 108, 355 and 38 patients respectively). Serum Cobalt and Chromium levels were assessed for each group and multivariant analysis used to create a regression model. Results: Mean time between the procedures and the blood results for the BHR, BMHR, non-cemented stem THR and R3 groups were 40, 35.5, 41.7 and 36.6 months respectively. After adjusting for other potential confounders like head size and gender there was liner relationship between number of articulations and S. Cobalt with positive coefficient values started from 0.25 in BMHR to 0.4 in R3 (P value<0.000:R21⁄411.65). Gender is a positive influence factor, which increases relationship linearity across all designs (P value<0.000:R21⁄413) S. Chromium did not fit the regression model as S. cobalt. Conclusions: There is statistically significant positive proportional relationship between increasedmodularity of MOM hip implants and S. Cobalt accumulation in patients' blood samples. 0731: GETTING TO GRIPS WITH THE BEST PRACTICE TARIFF FOR NECK OF FEMUR FRACTURES, EXPERIENCES FROM A MAJOR TRAUMA CENTRE: A COMPLETED AUDIT LOOP Iain Rankin , Amy Bibby, Reza Jenabzadeh, Dylan Griffiths, Rajarshi Bhattacharya. Department of Trauma and Orthopaedics, St Mary's Hospital, Imperial College Healthcare NHS Trust, London, UK. Introduction: The Best Practice Tariff (BPT) introduced in 2010 aims to financially incentivize hospitals to optimize management of patients with neck of femur (NOF) fractures, utilizing a multidisciplinary approach against set criteria. Major Trauma Centres face challenges in the prioritisation of major trauma patients against fractured NOF patients. This audit examined compliance at a regional Major Trauma Centre, managing acute admissions in conjunction with transfers from a second site within the same trust, prior to and following implementation of a NOF Action Group. Methods: A retrospective audit of our compliance to BPT was conducted for the months of April December 2012, repeated January September 2013 following implementation of a NOF Action Group aimed to improve workflow. Results: 237 patients in 2012 and 236 patients in 2013 were eligible for BPT. Implementation of a NOFAction Group improved outcomes: BPT in all criteria increased from 46.8% to 71.2%; (p<0.001), with the most notable improvement in the rates for time to theatre <36 hours 57.6% to 80.5% (p<0.001). The financial implications were an estimated additional £77,235 for the trust. Conclusions: Implementation of a NOF Action Group improves compliance with BPT in a Major Trauma Centre, despite the challenges faced. 0739: THE ROLE OF EXOGEN IN NON-UNIONS, DOES IT SHOW ANY CLINICAL BENEFIT IN A LARGE DISTRICT GENERAL HOSPITAL? Nader Ibrahim , Devendra Mahadevan, Ramanathan Natarajan, James Rudd, William Groom. Northampton General Hospital, Northampton,