Oxidised zirconium (OxZi) has been developed
as an alternative bearing surface for femoral heads in total hip arthroplasty
(THA). This study has investigated polyethylene wear, functional
outcomes and complications, comparing OxZi and cobalt–chrome (CoCr)
as part of a three-arm, multicentre randomised controlled trial.
Patients undergoing THA from four institutions were prospectively
randomised into three groups. Group A received a CoCr femoral head
and highly cross-linked polyethylene (XLPE) liner; Group B received
an OxZi femoral head and XLPE liner; Group C received an OxZi femoral
head and ultra-high molecular weight polyethylene (UHMWPE) liner.
At five years, 368 patients had no statistically significant differences
in short-form-36 (p = 0.176 mental, p = 0.756 physical), Western
Ontario and McMaster Universities Osteoarthritis Index (p = 0.847),
pain scores
(p = 0.458) or complications. The mean rate of linear wear was 0.028
mm/year (standard deviation ( Cite this article:
The aim of this study was to evaluate the ten-year
clinical and functional outcome of hip resurfacing and to compare it
with that of cementless hip arthroplasty in patients under the age
of 55 years. Between 1999 and 2002, 80 patients were enrolled into the study:
24 were randomised (11 to hip resurfacing, 13 to total hip arthroplasty),
18 refused hip resurfacing and chose cementless total hip arthroplasty
with a 32 mm bearing, and 38 insisted on resurfacing. The mean follow-up
for all patients was 12.1 years (10 to 14). Patients were assessed clinically and radiologically at one year,
five years and ten years. Outcome measures included EuroQol EQ5D,
Oxford, Harris hip, University of California Los Angeles and University
College Hospital functional scores. No differences were seen between the two groups in the Oxford
or Harris hip scores or in the quality of life scores. Despite a
similar aspiration to activity pre-operatively, a higher proportion
of patients with a hip resurfacing were running and involved in
sport and heavy manual labour after ten years. We found significantly higher function scores in patients who
had undergone hip resurfacing than in those with a cementless hip
arthroplasty at ten years. This suggests a functional advantage
for hip resurfacing. There were no other attendant problems. Cite this article:
The aim of this study was to assess the effect
of frictional torque and bending moment on fretting corrosion at
the taper interface of a modular femoral component and to investigate
whether different combinations of material also had an effect. The
combinations we examined were 1) cobalt–chromium (CoCr) heads on
CoCr stems 2) CoCr heads on titanium alloy (Ti) stems and 3) ceramic
heads on CoCr stems. In test 1 increasing torque was imposed by offsetting the stem
in the anteroposterior plane in increments of 0 mm, 4 mm, 6 mm and
8 mm when the torque generated was equivalent to 0 Nm, 9 Nm, 14
Nm and 18 Nm. In test 2 we investigated the effect of increasing the bending
moment by offsetting the application of axial load from the midline
in the mediolateral plane. Increments of offset equivalent to head
+ 0 mm, head + 7 mm and head + 14 mm were used. Significantly higher currents and amplitudes were seen with increasing
torque for all combinations of material. However, Ti stems showed
the highest corrosion currents. Increased bending moments associated
with using larger offset heads produced more corrosion: Ti stems
generally performed worse than CoCr stems. Using ceramic heads did
not prevent corrosion, but reduced it significantly in all loading
configurations. Cite this article:
Revision total knee arthroplasty (TKA) is a complex
procedure which carries both a greater risk for patients and greater
cost for the treating hospital than does a primary TKA. As well
as the increased cost of peri-operative investigations, blood transfusions,
surgical instrumentation, implants and operating time, there is
a well-documented increased length of stay which accounts for most
of the actual costs associated with surgery. We compared revision surgery for infection with revision for
other causes (pain, instability, aseptic loosening and fracture).
Complete clinical, demographic and economic data were obtained for
168 consecutive revision TKAs performed at a tertiary referral centre
between 2005 and 2012. Revision surgery for infection was associated with a mean length
of stay more than double that of aseptic cases (21.5 Current NHS tariffs do not fully reimburse the increased costs
of providing a revision knee surgery service. Moreover, especially
as greater costs are incurred for infected cases. These losses may
adversely affect the provision of revision surgery in the NHS. Cite this article:
Revision knee arthroplasty presents a number
of challenges, not least of which is obtaining solid primary fixation
of implants into host bone. Three anatomical zones exist within
both femur and tibia which can be used to support revision implants.
These consist of the joint surface or epiphysis, the metaphysis
and the diaphysis. The methods by which fixation in each zone can
be obtained are discussed. The authors suggest that solid fixation
should be obtained in at least two of the three zones and emphasise
the importance of pre-operative planning and implant selection. Cite this article:
Trauma and Orthopaedic care has been through
a rapid evolution over the past few decades. This Editorial discusses
some of the advances. Cite this article:
The routine use of patient reported outcome measures
(PROMs) in evaluating the outcome after arthroplasty by healthcare
organisations reflects a growing recognition of the importance of
patients’ perspectives in improving treatment. Although widely embraced
in the NHS, there are concerns that PROMs are being used beyond
their means due to a poor understanding of their limitations. This paper reviews some of the current challenges in using PROMs
to evaluate total knee arthroplasty. It highlights alternative methods
that have been used to improve the assessment of outcome. Cite this article:
The Unified Classification System (UCS) was introduced
because of a growing need to have a standardised universal classification
system of periprosthetic fractures. It combines and simplifies many
existing classification systems, and can be applied to any fracture
around any partial or total joint replacement occurring during or
after operation. Our goal was to assess the inter- and intra-observer
reliability of the UCS in association with knee replacement when
classifying fractures affecting one or more of the femur, tibia
or patella. We used an international panel of ten orthopaedic surgeons with
subspecialty fellowship training and expertise in adult hip and
knee reconstruction (‘experts’) and ten residents of orthopaedic
surgery in the last two years of training (‘pre-experts’). They
each received 15 radiographs for evaluation. After six weeks they
evaluated the same radiographs again but in a different order. The reliability was assessed using the Kappa and weighted Kappa
values. The Kappa values for inter-observer reliability for the experts
and the pre-experts were 0.741 (95% confidence interval (CI) 0.707
to 0.774) and 0.765 (95% CI 0.733 to 0.797), respectively. The weighted
Kappa values for intra-observer reliability for the experts and
pre-experts were 0.898 (95% CI 0.846 to 0.950) and 0.878 (95% CI
0.815 to 0.942) respectively. The UCS has substantial inter-observer reliability and ‘near
perfect’ intra-observer reliability when used for periprosthetic
fractures in association with knee replacement in the hands of experienced
and inexperienced users. Cite this article:
We are currently facing an epidemic of periprosthetic
fractures around the hip. They may occur either during surgery or
post-operatively. Although the acetabulum may be involved, the femur
is most commonly affected. We are being presented with new, difficult
fracture patterns around cemented and cementless implants, and we
face the challenge of an elderly population who may have grossly
deficient bone and may struggle to rehabilitate after such injuries.
The correct surgical management of these fractures is challenging.
This article will review the current choices of implants and techniques
available to deal with periprosthetic fractures of the femur. Cite this article:
The Unified Classification System (UCS) emphasises
the key principles in the assessment and management of peri-prosthetic
fractures complicating partial or total joint replacement. We tested the inter- and intra-observer agreement for the UCS
as applied to the pelvis and femur using 20 examples of peri-prosthetic
fracture in 17 patients. Each subtype of the UCS was represented
by at least one case. Specialist orthopaedic surgeons (experts)
and orthopaedic residents (pre-experts) assessed reliability on
two separate occasions. For the pelvis, the UCS showed inter-observer agreement of 0.837
(95% confidence intervals (CI) 0.798 to 0.876) for the experts and
0.728 (95% CI 0.689 to 0.767) for the pre-experts. The intra-observer
agreement for the experts was 0.861 (95% CI 0.760 to 0.963) and
0.803 (95% 0.688 to 0.918) for the pre-experts. For the femur, the
UCS showed an inter-observer kappa value of 0.805 (95% CI 0.765
to 0.845) for the experts and a value of 0.732 (95% CI 0.690 to 0.773)
for the pre-experts. The intra-observer agreement was 0.920 (95%
CI 0.867 to 0.973) for the experts, and 0.772 (95% CI 0.652 to 0.892)
for the pre-experts. This corresponds to a substantial and ‘almost
perfect’ inter- and intra-observer agreement for the UCS for peri-prosthetic
fractures of the pelvis and femur. We hope that unifying the terminology of these injuries will
assist in their assessment, treatment and outcome. Cite this article:
