Aims. Loosening of components after total knee arthroplasty (TKA) can be associated with the development of
The
Introduction: Prostheses
Aims. This multicentre retrospective observational study’s aims were to investigate whether there are differences in the occurrence of
Aims. Post-operative migration of cemented acetabular components as
measured by radiostereometric analysis (RSA) has a strong predictive
power for late, aseptic loosening. Also,
Aims. We aimed to evaluate the long-term outcome of highly cross-linked polyethylene (HXLPE) cemented acetabular components and assess whether any
The Oxford unicompartmental knee replacement gives good results in patients with symptomatic osteoarthritis of the medial compartment. Previous studies have suggested that the presence of
Survivorship of unicondylar knee replacement (UKR) exceeds 85% at 10 years. During long term follow-up, progressive osteoarthritis (OA) and loosening are typical of UKR failure. The decision to revise UKR is complex as radiographic findings are not always consistent with clinical symptoms. This study of revised UKR compares intraoperative assessment of component fixation and progressive OA with prerevision radiographic evaluations. Twenty-seven UKR were retrieved from 22 female and 5 male patients. Patient age and time in situ averaged 76 (68–87) years and 79 (25–156) months, respectively. At index arthroplasty, all knees received a fixed-bearing medial UKR with cement fixation. Prior to revision,
Introduction. Various 2D and 3D surfaces are available for cementless fixation of acetabular cups. The goal of these surface modifications is to improve fixation between the metallic cups and surrounding bone. Radiographs have historically been used to evaluate the implant-to-bone fixation around the acetabular cups. In general, a well fixed cup shows no gaps or radiolucency around the cup's outer diameter. In post-operative radiographs, the presence of progressive radiolucent zones of 2mm or more around the implant in the three radiographic zones is indicative of aseptic loosening, as described by DeLee and Charnley [1]. In this cadaveric study, we investigated the X-ray image characteristics of two different types of acetabular shell surfaces (2D and 3D) to evaluate the implant-to-bone interface in the two designs. Methods. Six human cadavers were bilaterally implanted with acetabular cups by an orthopaedic surgeon. 2D surface cups (Trident, Stryker, Mahwah, NJ) and 3D surface cups (Tritanium, Stryker, Mahwah, NJ) were randomized between the left and right acetabula. The surgeon used his regular surgical technique (1 mm under reaming) to implant the acetabular cups. The cadavers were sent for X-ray imaging after the operation, Figure 1A. Following the X-ray imaging, the acetabular cups were carefully resected from the cadavers. Enough bone around the cups was retained for analysis of the implant-to-bone interface by contact X-ray. The acetabular cups with the surrounding bone were fixed in 70% isopropyl alcohol for about a week and subsequently embedded in polymethyl methacrylate. The embedded cups were sectioned at 30° intervals using a diamond saw in the coronal plane, as recommended by Engh et al [2], Figure 1B. The sectioning of the samples produced 6 slices of each cup where the implant-bone interface could easily be visualized for evaluation with contact X-ray. Results. The AP X-rays of the cadavers demonstrated
A total of 397 hips were randomised to receive
Metasul metal-on-metal (MoM), metal-on-conventional polyethylene (MoP)
or ceramic-on-polyethylene (CoP) bearings using a cemented triple-tapered
polished femoral component (MS-30). There were 129 MoM hips in 123
patients (39 male and 84 female, mean age 63.3 years (40.7 to 72.9)),
137 MoP hips in 127 patients (39 male and 88 female, mean age 62.8
years (24.5 to 72.7)) and 131 CoP hips in 124 patients (51 male
and 73 female, mean age 63.9 years (30.6 to 73.8)). All acetabular
components were cemented Weber polyethylene components with the
appropriate inlay for the MoM articulation. Clinical evaluation
was undertaken using the Harris hip score (HHS) and radiological
assessments were made at two, five and seven years. The HHS and radiological
analysis were available for 341 hips after seven years. The MoM
group had the lowest mean HHS (p = 0.124), a higher rate of revision
(p <
0.001) and a higher incidence of
When
We studied 185 total hip replacements and related the identification of
OBJECTIVE OF THE STUDY. The objective of this study is to establish the medium-term clinical and radiological results with the cementless three-dimensional Vektor-Titan stem compared with conventional cementless stem, such as PerFix stem. The latter stem has a double-wedge design with a rounded distal portion for canal filling (Fig. 1). MATERIALS AND METHODS. From July, 2004, to May, 2010, fifty seven Vektor-Titan stems and 150 PerFix stems were implanted for the patients with osteoarthritis, avascular necrosis, femoral neck fracture, and rheumatoid arthritis in our hospital. The results were evaluated clinically using Japanese Orthopedic Association (JOA) scores and the Merle d’Aubigne and Postel (M&P) scores. Radiographs were analyzed retrospectively. The criteria used for determining loosening were migration or a total radiolucent zone between the prosthesis/bone cement and host bone, wherein the width increased progressively or change of position, i.e., migration or subsidence of the prosthesis. Migration of the socket seen on the radiograph was defined as either the presence of a ≥2-mm position change or rotation. Position changes of the stem seen on the radiograph were defined as the presence of a progressive subsidence of ≥2 mm or change of position, e.g., varus or valgus. The follow-up period was 9.2 ± 2.6 (range, 5.0–14.0) years. RESULTS. One patient had intraoperative femoral shaft fracture and healed by conservative treatment. The mean JOA and M&P scores improved from preoperative 39.3 and 6.8 points to postoperative 90.9 and 17.2 points, respectively. Thigh pain was less frequent for Vektor-Titan stems (Table 1).
Higher than expected rates of tibial loosening with the ATTUNE® total knee arthroplasty (TKA) implant has been reported. Component loosening can be associated with the development of radiolucency lines (RLL) and our study aim was to systematically assess the reported rates of these. A systematic search was undertaken using the Cochrane methodology in four online databases. Identified studies were assessed and screened against predetermined inclusion criteria. Meta-analysis was conducted using a random-effects model.Abstract
Introduction
Methodology
Introduction. The clinical impact of
Introduction. Humeral
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
To compare the RLLs following single mix and dual mix cementation techniques.
Aims. In 2015, we published the results of our ceramic-on-metal (CoM) total hip arthroplasties (THAs) performed between October 2007 and July 2009 with a mean follow-up of 34 months (23 to 45) and a revision rate of 3.1%. The aim of this paper is to present the longer-term outcomes. Methods. A total of 264 patients were reviewed at a mean of 5.8 years (4.6 to 7.2) and 10.1 years (9.2 to 10.6) to determine revision rate, pain, outcome scores, radiological analysis, and blood ion levels. Those who were unwilling or unable to travel were contacted by telephone. Results. The all-cause revision rate at six years was 3.1% (eight THAs), increasing to 8.8% (18 THAs) at ten years. Of these, there were four and then seven bearing-related revisions at six and ten years, respectively. There was a statistically significant deterioration in the visual analogue scale pain score and Oxford Hip Score (OHS) between six and ten years. There were 18 CoM THAs in 17 patients who had a cobalt or chromium level over 4 ppb and ten CoM THAs in nine patients who had a cobalt or chromium level higher than 7 ppb with a statistically significant increase in chromium levels only between the two timepoints. Overall, 84 stems (39.1%) had significant