Obesity has been associated with higher complication rates and poorer outcomes following joint replacement surgery. Body mass index (BMI) is a simple index of body composition and forms part of preoperative assessment. It does not take into account the proportion of lean mass and body fat and can give a false impression of body composition in healthy manual workers. A more accurate measure of body composition is available using non-invasive bioimpedance methods. This study aims to identify whether BMI provides an accurate measure of body fat composition in patients awaiting lower limb arthroplasty surgery. Consecutive patients attending for pre-assessment clinic prior to total knee and hip replacement surgery were examined. All patients had their BMI calculated and underwent bioimpedance testing using a bedside Bodystat 1500 scanner (Bodystat, UK).Introduction
Methods
The Oxford Knee Score is a well validated, commonly used scoring system. Previous studies have suggested that the score is influenced by demographic differences between patients in particular the functional component more than the pain and clinical components. The aim of this study was to further assess this using a large number of patients. The pre, 3 months and 12 months post-surgical Oxford Knee Scores were collected from 1492 patients from five distinct demographic locations undergoing total knee arthroplasty over twelve years under the care of 8 different consultants. A total of 735 patients had complete data sets. The scores were than analysed to test whether age, postcode, sex or consultant in charge had any significant effects on the outcome.Introduction
Methods
The Oxford Knee Score is a well validated, commonly used scoring system. Previous studies have suggested that the score is influenced by demographic differences between patients in particular the functional component more than the pain and clinical components. The aim of this study was to further assess this using a large number of patients. The pre, 3 months and 12 months post-surgical Oxford Knee Scores were collected from 1492 patients from five distinct demographic locations undergoing total knee arthroplasty over twelve years under the care of 8 different consultants. A total of 735 patients had complete data sets. The scores were than analysed to test whether age, postcode, sex or consultant in charge had any significant effects on the outcome.Introduction
Methods
We have examined 26 retrieved, failed titanium-alloy femoral stems. The clinical details, radiological appearances and the histology of the surrounding soft tissues in each patient were also investigated. The stems were predominantly of the flanged design and had a characteristic pattern of wear. A review of the radiographs showed a series of changes, progressive with time. The first was lateral debonding with subsidence of the stem. This was followed by calcar resorption and fragmentation or fracture of the cement. Finally, osteolysis was seen, starting with a radiolucency at the cement-bone interface and progressing to endosteal cavitation. Three histological appearances were noted: granulomatous, necrobiotic and necrotic. We suggest that an unknown factor, possibly related to the design of the stem, caused it to move early. After this, micromovement at the cement-stem interface led to the generation of particulate debris and fracture of the cement. A soft-tissue reaction to the debris resulted in osteolysis and failure of fixation of the prostheses.
