We have reviewed 25 cases of focal femoral osteolysis in radiographically stable, cemented femoral implants. In three hips retrieved at post-mortem from two patients, we have been able to make a detailed biomechanical and histological analysis. The interval between arthroplasty and the appearance of focal osteolysis on clinical radiographs ranged from 40 to 168 months, and in over 70% of the cases this did not appear until after five or more years. Few had significant pain and there was no relation to age, sex or original diagnosis. The most common site for osteolysis were Gruen zones 2 and 3 on the anteroposterior radiograph and zones 5 and 6 on the lateral radiograph. In 15 cases (60%), the area of osteolysis corresponded to either a defect in the cement mantle or an area of very thin cement. The rate of progression of these lesions was variable, but to date only one has progressed to gross loosening of the
The accurate reconstruction of hip anatomy and
biomechanics is thought to be important in achieveing good clinical
outcomes following total hip arthroplasty (THA). To this end some
newer hip designs have introduced further modularity into the design
of the
We present a retrospective series of 170 cemented titanium straight-stem
We reviewed 111 hemispherical Duraloc series-500 acetabular components with a minimum follow-up of 12 years. The mean clinical and radiological follow-up was 13.4 years (12 to 15). A Profile hydroxyapatite-coated anatomical
We present the extended follow-up (≥ 20 years)
of a series of fully hydroxyapatite-coated
Radiostereometric analysis (RSA) can detect early
micromovement in unstable implant designs which are likely subsequently
to have a high failure rate. In 2010, the Articular Surface Replacement
(ASR) was withdrawn because of a high failure rate. In 19 ASR femoral
components, the mean micromovement over the first two years after implantation
was 0.107 mm (. sd. 0.513) laterally, 0.055 mm (. sd. 0.204)
distally and 0.150 mm (. sd. 0.413) anteriorly. The mean backward
tilt around the x-axis was -0.08° (. sd. 1.088), mean internal
rotation was 0.165° (. sd. 0.924) and mean varus tilt 0.238°
(. sd. 0.420). The baseline to two-year varus tilt was statistically
significant from zero movement, but there was no significant movement
from one year onwards. We conclude that the ASR
In this meta-analysis we included 32 English-language articles published between January 1975 and June 2004 on the diagnostic performance of plain radiography, subtraction arthrography, nuclear arthrography and bone scintigraphy in detecting aseptic loosening of the
In recent years, the use of a collared cementless femoral prosthesis has risen in popularity. The design intention of collared components is to transfer some load to the resected femoral calcar and prevent implant subsidence within the cancellous bone of the metaphysis. Conversely, the load transfer for a cemented femoral prosthesis depends on the cement-component and cement-bone interface interaction. The aim of our study was to compare the three most commonly used collared cementless components and the three most commonly used tapered polished cemented components in patients aged ≥ 75 years who have undergone a primary total hip arthroplasty (THA) for osteoarthritis (OA). Data from the Australian Orthopaedic Association National Joint Replacement Registry from 1 September 1999 to 31 December 2022 were analyzed. Collared cementless femoral components and cemented components were identified, and the three most commonly used components in each group were analyzed. We identified a total of 11,278 collared cementless components and 47,835 cemented components. Hazard ratios (HRs) from Cox proportional hazards models, adjusting for age and sex, were obtained to compare the revision rates between the groups.Aims
Methods
Revision surgery of the hip was performed on 114 hips using an extensively porous-coated
We have compared the survival of 67 revision arthroplasties of the knee undertaken for aseptic loosening with and without the retention of a secure, cemented
We studied the results of total hip arthroplasty (THA) using AML porous-coated
We performed a three-year radiostereometric analysis (RSA) study of the Elite Plus
Our aim in this pilot study was to evaluate the fixation of, the bone remodelling around, and the clinical outcome after surgery of a new, uncemented, fully hydroxyapatite-coated, collared and tapered
Resurfacing arthroplasties of the hip are being undertaken with increasing frequency and the complications associated with this procedure are well documented. We have encountered a further problem with a fracture of the centralising peg of the
Objectives. Orthopaedic surgeons use stems in revision knee surgery to obtain
stability when metaphyseal bone is missing. No consensus exists
regarding stem size or method of fixation. This in vitro study
investigated the influence of stem length and method of fixation
on the pattern and level of relative motion at the bone–implant
interface at a range of functional flexion angles. Methods. A custom test rig using differential variable reluctance transducers
(DVRTs) was developed to record all translational and rotational
motions at the bone–implant interface. Composite femurs were used.
These were secured to permit variation in flexion angle from 0°
to 90°. Cyclic loads were applied through a tibial component based
on three peaks corresponding to 0°, 10° and 20° flexion from a normal
walking cycle. Three different
Periprosthetic hip fractures (PPFs) after total hip arthroplasty are difficult to treat. Therefore, it is important to identify modifiable risk factors such as stem selection to reduce the occurrence of PPFs. This study aimed to clarify differences in fracture torque, surface strain, and fracture type analysis between three different types of cemented stems. We conducted biomechanical testing of bone analogues using six cemented stems of three different types: collarless polished tapered (CPT) stem, Versys Advocate (Versys) stem, and Charnley-Marcel-Kerboull (CMK) stem. Experienced surgeons implanted each of these types of stems into six bone analogues, and the analogues were compressed and internally rotated until failure. Torque to fracture and fracture type were recorded. We also measured surface strain distribution using triaxial rosettes.Aims
Methods
We have tested the axial and torsional stability of
Aims. The widely used and well-proven Palacos R (a.k.a. Refobacin Palacos
R) bone cement is no longer commercially available and was superseded
by Refobacin bone cement R and Palacos R + G in 2005. However, the
performance of these newly introduced bone cements have not been
tested in a phased evidence-based manner, including roentgen stereophotogrammetric
analysis (RSA). Patients and Methods. In this blinded, randomised, clinical RSA study, the migration
of the Stanmore
Concerns have been reported to the United Kingdom
National Patient Safety Agency, warning that cementing the femoral component
during hip replacement surgery for fracture of the proximal femur
may increase peri-operative mortality. . The National Hip Fracture Database collects demographic and outcome
data about patients with a fracture of the proximal femur from over
100 participating hospitals in the United Kingdom. We conducted
a mixed effects logistic regression analysis of this dataset to
determine whether peri-operative mortality was increased in patients
who had undergone either hemiarthroplasty or total hip replacement
using a cemented
Torsional instability of