Total hip arthroplasty (THA) in patients with congenital dysplasia of the hip (CDH) is complex and challenging. The Crowe and Hartofilakidis classification systems are the most commonly used. However, neither encompasses the whole spectrum of disease and deformity and therefore does not guide modern surgical options. We present a new classification system which aims to guide surgical strategy by focusing on the three main areas of disease and deformity: The aim of this study is to assess the reliability of this new adult CDH classification system in the setting of THA. A sample size calculation showed 28 evaluations were required to reach a power of 85% (based on a kappa value of 0.4). The anterior-posterior pelvis and lateral hip radiographs of 30 hips, in 26 patients were evaluated by three Consultant Orthopaedic Surgeons using the classification detailed in table 1. A second evaluation, with the case order randomised, was performed after a minimum period of 1month. Randolph's free multi-rater Kappa co-efficient was used to assess for inter and intra- observer reliability and 95% confidence intervals were calculated.Background
Study design and Methods
The highly cross-linked polyethylene Exeter RimFit flanged cemented
acetabular component was introduced in the United Kingdom in 2010.
This study aimed to examine the rates of emergence of radiolucent
lines observed when the Rimfit acetabular component was implanted
at total hip arthroplasty (THA) using two different techniques: firstly,
the ‘rimcutter’ technique in which the flange sits on a pre-prepared
acetabular rim; and secondly, the ‘trimmed flange’ technique in
which the flange is trimmed and the acetabular component is seated
inside the rim of the acetabulum. The radiographs of 150 THAs (75 ‘rimcutter’, 75 ‘trimmed flange’)
involving this component were evaluated to assess for radiolucencies
at the cement/bone interface by three observers. Aims
Patients and Methods