We evaluated the short-term functional outcome and prevalence
of bearing-specific generation of audible noise in 301 patients
(336 hips) operated on with fourth generation (Delta) medium diameter
head, ceramic-on-ceramic (CoC) total hip arthroplasties (THAs). There were 191 female (63%) and 110 male patients (37%) with
a mean age of 61 years (29 to 78) and mean follow-up of 2.1 years
(1.3 to 3.4). Patients completed three questionnaires: Oxford Hip
Score (OHS), Research and Development 36-item health survey (RAND-36)
and a noise-specific symptom questionnaire. Plain radiographs were also
analysed. A total of three hips (0.9%) were revised. Aims
Patients and Methods
The optimal treatment for independent patients with a displaced
intracapsular fracture of the hip remains controversial. The recognised
alternatives are hemiarthroplasty and total hip arthroplasty. At
present there is no established standard of care, with both types
of arthroplasty being used in many centres. We conducted a feasibility study comparing the clinical effectiveness
of a dual mobility acetabular component compared with standard polyethylene
component in total hip arthroplasty for independent patients with
a displaced intracapsular fracture of the hip, for a 12-month period
beginning in June 2013. The primary outcome was the risk of dislocation
one year post-operatively. Secondary outcome measures were EuroQol
5 Dimensions, ICEpop CAPability measure for Older people, Oxford
hip score, mortality and re-operation.Aims
Patients and Methods
A contact patch to rim (CPR) distance of <
10 mm has been
associated with edge-loading and excessive wear. However, not all
arthroplasties with a low CPR distance show problems with wear.
Therefore, CPR distance may not be the only variable affecting the
post-operative metal ion concentrations. We used multiple logistic regression to determine what variables
differed between the patients who had high and low cobalt (CoS)
and chromium (CrS) serum ion concentrations within a cohort of patients
with low (<
10 mm) CPR distances. A total of 56 patients treated
with unilateral hip resurfacing arthroplasty (HRA) had CoS and CrS
ion studies performed more than one year after surgery. The mean
age of the patients at the time of surgery was 51.7 years (29 to
70), with 38 women (68%) and 18 men (32%).Aims
Patients and Methods
Long-term clinical outcomes for ceramic-on-ceramic (CoC) bearings
are encouraging. However, there is a risk of squeaking. Guidelines
for the orientation of the acetabular component are defined from
static imaging, but the position of the pelvis and thus the acetabular
component during activities associated with edge-loading are likely
to be very different from those measured when the patient is supine.
We assessed the functional orientation of the acetabular component. A total of 18 patients with reproducible squeaking in their CoC
hips during deep flexion were investigated with a control group
of 36 non-squeaking CoC hips. The two groups were matched for the
type of implant, the orientation of the acetabular component when
supine, the size of the femoral head, ligament laxity, maximum hip
flexion and body mass index. Aims
Patients and Methods
Surgeons have commonly used modular femoral heads and stems from
different manufacturers, although this is not recommended by orthopaedic
companies due to the different manufacturing processes. We compared the rate of corrosion and rate of wear at the trunnion/head
taper junction in two groups of retrieved hips; those with mixed
manufacturers (MM) and those from the same manufacturer (SM). We identified 151 retrieved hips with large-diameter cobalt-chromium
heads; 51 of two designs that had been paired with stems from different
manufacturers (MM) and 100 of seven designs paired with stems from
the same manufacturer (SM). We determined the severity of corrosion
with the Goldberg corrosion score and the volume of material loss
at the head/stem junction. We used multivariable statistical analysis
to determine if there was a significant difference between the two
groups. Aims
Materials and Methods
The pelvis rotates in the sagittal plane during daily activities.
These rotations have a direct effect on the functional orientation
of the acetabulum. The aim of this study was to quantify changes
in pelvic tilt between different functional positions. Pre-operatively, pelvic tilt was measured in 1517 patients undergoing
total hip arthroplasty (THA) in three functional positions – supine,
standing and flexed seated (the moment when patients initiate rising
from a seated position). Supine pelvic tilt was measured from CT
scans, standing and flexed seated pelvic tilts were measured from standardised
lateral radiographs. Anterior pelvic tilt was assigned a positive
value.Aims
Patients and Methods
Studies reporting specifically on squeaking in total hip arthroplasty have focused on cementless, and not on hybrid, fixation. We hypothesised that the cement mantle of the femur might have a damping effect on the sound transmitted through the metal stem. The objective of this study was to test the effect of cement on sound propagation along different stem designs and under different fixation conditions. An Objectives
Methods
Following the resection of an extensive amount of bone in the
treatment of a tumour, the residual segment may be insufficient
to accept a standard length intramedullary cemented stem. Short-stemmed
endoprostheses conceivably have an increased risk of aseptic loosening.
Extra-cortical plates have been added to minimise this risk by supplementing
fixation. The aim of this study was to investigate the survivorship
of short-stemmed endoprostheses and extra-cortical plates. The study involved 37 patients who underwent limb salvage surgery
for a primary neoplasm of bone between 1998 and 2013. Endoprosthetic
replacement involved the proximal humerus in nine, the proximal
femur in nine, the distal femur in 13 and the proximal tibia in
six patients. There were 12 primary (32%) and 25 revision procedures (68%).
Implant survivorship was compared with matched controls. The amount
of bone that was resected was >
70% of its length and statistically
greater than the standard control group at each anatomical site.Aims
Patients and Methods
The aim of this study was to determine whether the rates of revision
for metal-on-metal (MoM) total hip arthroplasties (THAs) with Pinnacle
components varied according to the year of the initial operation,
and compare these with the rates of revision for other designs of
MoM THA. Data from the National Joint Registry for England and Wales included
36 mm MoM THAs with Pinnacle acetabular components which were undertaken
between 2003 and 2012 with follow-up for at least five years (n
= 10 776) and a control group of other MoM THAs (n = 13 817). The
effect of the year of the primary operation on all-cause rates of revision
was assessed using Cox regression and interrupted time-series analysis.Aims
Patients and Methods
Free vascularised fibular grafting has been used for the treatment
of large bony defects for more than 40 years. However, there is
little information about the risk factors for failure and whether
newer locking techniques of fixation improve the rates of union.
The purpose of this study was to compare the rates of union of free
fibular grafts fixed with locking and traditional techniques, and
to quantify the risk factors for nonunion and failure. A retrospective review involved 134 consecutive procedures over
a period of 20 years. Of these, 25 were excluded leaving 109 patients
in the study. There were 66 men and 43 women, with a mean age of
33 years (5 to 78). Most (62) were performed for oncological indications,
and the most common site (52) was the lower limb. Rate of union
was estimated using the Kaplan-Meier method and risk factors for
nonunion were assessed using Cox regression. All patients were followed
up for at least one year.Aims
Patients and Methods
The high revision rates of the DePuy Articular Surface Replacement (ASR) and the DePuy ASR XL (the total hip arthroplasty (THA) version) have led to questions over the viability of metal-on-metal (MoM) hip joints. Some designs of MoM hip joint do, however, have reasonable mid-term performance when implanted in appropriate patients. Investigations into the reasons for implant failure are important to offer help with the choice of implants and direction for future implant designs. One way to assess the performance of explanted hip prostheses is to measure the wear (in terms of material loss) on the joint surfaces. In this study, a coordinate measuring machine (CMM) was used to measure the wear on five failed cementless Biomet Magnum/ReCap/ Taperloc large head MoM THAs, along with one Biomet ReCap resurfacing joint. Surface roughness measurements were also taken. The reason for revision of these implants was pain and/or adverse reaction to metal debris (ARMD) and/or elevated blood metal ion levels.Objectives
Methods
To evaluate the effectiveness of an institutionally developed
algorithm for evaluation and diagnosis of prosthetic joint injection
and to determine the impact of this protocol on overall hospital
re-admissions.p We retrospectively evaluated 2685 total hip arthroplasty (THA)
and total knee arthroplasty (TKA) patients prior to (1263) and following
(1422) the introduction of an infection detection protocol. The
protocol used conservative thresholds for C-reactive protein to
direct the medical attendant to aspirate the joint. The protocol
incorporated a clear set of laboratory and clinical criteria that
allowed a patient to be discharged home if all were met. Patients were
included if they presented to our emergency department within 120
days post-operatively with concerns for swelling, pain or infection
and were excluded if they had an unambiguous infection or if their
chief complaint was non-orthopaedic in nature.Aims
Patients and Methods
Since redesign of the Oxford phase III mobile-bearing unicompartmental
knee arthroplasty (UKA) femoral component to a twin-peg design,
there has not been a direct comparison to total knee arthroplasty
(TKA). Thus, we explored differences between the two cohorts. A total of 168 patients (201 knees) underwent medial UKA with
the Oxford Partial Knee Twin-Peg. These patients were compared with
a randomly selected group of 177 patients (189 knees) with primary
Vanguard TKA. Patient demographics, Knee Society (KS) scores and
range of movement (ROM) were compared between the two cohorts. Additionally,
revision, re-operation and manipulation under anaesthesia rates
were analysed.Aims
Patients and Methods
The interest in unicompartmental knee arthroplasty (UKA) for
medial osteoarthritis has increased rapidly but the long-term follow-up
of the Oxford UKAs has yet to be analysed in non-designer centres.
We have examined our ten- to 15-year clinical and radiological follow-up
data for the Oxford Phase III UKAs. Between January 1999 and January 2005 a total of 138 consecutive
Oxford Phase III arthroplasties were performed by a single surgeon
in 129 patients for medial compartment osteoarthritis (71 right
and 67 left knees, mean age 72.0 years (47 to 91), mean body mass
index 28.2 (20.7 to 52.2)). Both clinical data and radiographs were
prospectively recorded and obtained at intervals. Of the 129 patients,
32 patients (32 knees) died, ten patients (12 knees) were not able
to take part in the final clinical and radiological assessment due
to physical and mental conditions, but via telephone interview it
was confirmed that none of these ten patients (12 knees) had a revision
of the knee arthroplasty. One patient (two knees) was lost to follow-up.Aims
Patients and Methods
To determine ten-year failure rates following 36 mm metal-on-metal
(MoM) Pinnacle total hip arthroplasty (THA), and identify predictors
of failure. We retrospectively assessed a single-centre cohort of 569 primary
36 mm MoM Pinnacle THAs (all Corail stems) followed up since 2012
according to Medicines and Healthcare Products Regulation Agency
recommendations. All-cause failure rates (all-cause revision, and
non-revised cross-sectional imaging failures) were calculated, with predictors
for failure identified using multivariable Cox regression.Aims
Patients and Methods