The optimum cementing technique for the tibial
component in cemented primary total knee replacement (TKR) remains
controversial. The technique of cementing, the volume of cement
and the penetration are largely dependent on the operator, and hence
large variations can occur. Clinical, experimental and computational
studies have been performed, with conflicting results. Early implant
migration is an indication of loosening. Aseptic loosening is the
most common cause of failure in primary TKR and is the product of
several factors. Sufficient penetration of cement has been shown
to increase implant stability. This review discusses the relevant literature regarding all aspects
of the cementing of the tibial component at primary TKR. Cite this article:
The technique of femoral cement-in-cement revision
is well established, but there are no previous series reporting its
use on the acetabular side at the time of revision total hip replacement.
We describe the technique and report the outcome of 60 consecutive
acetabular cement-in-cement revisions in 59 patients at a mean follow-up
of 8.5 years (5 to 12). All had a radiologically and clinically
well-fixed acetabular cement mantle at the time of revision. During
the follow-up 29 patients died, but no hips were lost to follow-up.
The two most common indications for acetabular revision were recurrent
dislocation (46, 77%) and to complement femoral revision (12, 20%). Of the 60 hips, there were two cases of aseptic loosening of
the acetabular component (3.3%) requiring re-revision. No other
hip was clinically or radiologically loose (96.7%) at the latest
follow-up. One hip was re-revised for infection, four for recurrent
dislocation and one for disarticulation of a constrained component.
At five years the Kaplan-Meier survival rate was 100% for aseptic
loosening and 92.2% (95% CI 84.8 to 99.6), with revision for any cause
as the endpoint. These results support the use of cement-in-cement revision on
the acetabular side in appropriate cases. Theoretical advantages
include preservation of bone stock, reduced operating time, reduced
risk of complications and durable fixation.
This study demonstrates a significant correlation
between the American Knee Society (AKS) Clinical Rating System and
the Oxford Knee Score (OKS) and provides a validated prediction
tool to estimate score conversion. A total of 1022 patients were prospectively clinically assessed
five years after TKR and completed AKS assessments and an OKS questionnaire.
Multivariate regression analysis demonstrated significant correlations between
OKS and the AKS knee and function scores but a stronger correlation
(r = 0.68, p <
0.001) when using the sum of the AKS knee and
function scores. Addition of body mass index and age (other statistically
significant predictors of OKS) to the algorithm did not significantly
increase the predictive value. The simple regression model was used to predict the OKS in a
group of 236 patients who were clinically assessed nine to ten years
after TKR using the AKS system. The predicted OKS was compared with
actual OKS in the second group. Intra-class correlation demonstrated
excellent reliability (r = 0.81, 95% confidence intervals 0.75 to
0.85) for the combined knee and function score when used to predict
OKS. Our findings will facilitate comparison of outcome data from
studies and registries using either the OKS or the AKS scores and
may also be of value for those undertaking meta-analyses and systematic
reviews. Cite this article:
The objective of this study was to explore dimensionality of
the Oxford Hip Score (OHS) and examine whether self-reported pain
and functioning can be distinguished in the form of subscales. This was a secondary data analysis of the UK NHS hospital episode
statistics/patient-reported outcome measures dataset containing
pre-operative OHS scores on 97 487 patients who were undergoing
hip replacement surgery. Objective
Methods
In a decidedly upper limb themed series of reviews this edition of Cochrane Corner summarises four new and updated reviews published by the Cochrane Bone, Joint and Muscle Trauma Group over the last few months. The tenacious reviewers at the Cochrane collaboration have turned their beady eyes to conservative treatments for shoulder dislocations and clavicle fractures along with evaluation of femoral nerve blocks in knee replacement and how to best manage entrapment injuries in children.
The Oxford knee score (OKS) is a validated and
widely accepted disease-specific patient-reported outcome measure,
but there is limited evidence regarding any long-term trends in
the score. We reviewed 5600 individual OKS questionnaires (1547
patients) from a prospectively-collected knee replacement database,
to determine the trends in OKS over a ten-year period following
total knee replacement. The mean OKS pre-operatively was 19.5 (95%
confidence interval (CI) 18.8 to 20.2). The maximum post-operative
OKS was observed at two years (mean score 34.4 (95% CI 33.7 to 35.2)),
following which a gradual but significant decline was observed through
to the ten-year assessment (mean score 30.1 (95% CI 29.1 to 31.1))
(p <
0.001). A similar trend was observed for most of the individual
OKS components (p <
0.001). Kneeling ability initially improved
in the first year but was then followed by rapid deterioration (p
<
0.001). Pain severity exhibited the greatest improvement, although
residual pain was reported in over two-thirds of patients post-operatively,
and peak improvement in the night pain component did not occur until
year four. Post-operative OKS was lower for women (p <
0.001),
those aged <
60 years (p <
0.003) and those with a body mass
index >
35 kg/m2 (p <
0.014), although similar changes
in scores were observed. This information may assist surgeons in
advising patients of their expected outcomes, as well as providing
a comparative benchmark for evaluating longer-term outcomes following
knee replacement. Cite this article:
To assess the sustainability of our institutional
bone bank, we calculated the final product cost of fresh-frozen femoral
head allografts and compared these costs with the use of commercial
alternatives. Between 2007 and 2010 all quantifiable costs associated
with allograft donor screening, harvesting, storage, and administration
of femoral head allografts retrieved from patients undergoing elective
hip replacement were analysed. From 290 femoral head allografts harvested and stored as full
(complete) head specimens or as two halves, 101 had to be withdrawn.
In total, 104 full and 75 half heads were implanted in 152 recipients.
The calculated final product costs were €1367 per full head. Compared
with the use of commercially available processed allografts, a saving
of at least €43 119 was realised over four-years (€10 780 per year)
resulting in a cost-effective intervention at our institution. Assuming
a price of between €1672 and €2149 per commercially purchased allograft,
breakeven analysis revealed that implanting between 34 and 63 allografts
per year equated to the total cost of bone banking. Cite this article:
We report the five year outcomes of a two-stage
approach for infected total hip replacement. This is a single-surgeon
experience at a tertiary centre where the more straightforward cases
are treated using single-stage exchange. This study highlights the
vital role of the multidisciplinary team in managing these cases. A total of 125 patients (51 male, 74 female) with a mean age
of 68 years (42 to 78) were reviewed prospectively. Functional status
was assessed using the Harris hip score (HHS). The mean HHS improved
from 38 (6 to 78.5) pre-operatively to 81.2 (33 to 98) post-operatively.
Staphylococcus species were isolated in 85 patients (68%). The rate of control of infection was 96% at five years. In all,
19 patients died during the period of the study. This represented
a one year mortality of 0.8% and an overall mortality of 15.2% at
five years. No patients were lost to follow-up. We report excellent control of infection in a series of complex
patients and infections using a two-stage revision protocol supported
by a multidisciplinary approach. The reason for the high rate of
mortality in these patients is not known. Cite this article:
Recent studies have shown that modulating inflammation-related
lipid signalling after a bone fracture can accelerate healing in
animal models. Specifically, decreasing 5-lipoxygenase (5-LO) activity
during fracture healing increases cyclooxygenase-2 (COX-2) expression
in the fracture callus, accelerates chondrogenesis and decreases
healing time. In this study, we test the hypothesis that 5-LO inhibition
will increase direct osteogenesis. Bilateral, unicortical femoral defects were used in rats to measure
the effects of local 5-LO inhibition on direct osteogenesis. The
defect sites were filled with a polycaprolactone (PCL) scaffold
containing 5-LO inhibitor (A-79175) at three dose levels, scaffold
with drug carrier, or scaffold only. Drug release was assessed Objectives
Methods
The aim of this study was to examine whether asymmetric loading
influences macrophage elastase (MMP12) expression in different parts
of a rat tail intervertebral disc and growth plate and if MMP12
expression is correlated with the severity of the deformity. A wedge deformity between the ninth and tenth tail vertebrae
was produced with an Ilizarov-type mini external fixator in 45 female
Wistar rats, matched for their age and weight. Three groups were
created according to the degree of deformity (10°, 30° and 50°).
A total of 30 discs and vertebrae were evaluated immunohistochemically
for immunolocalisation of MMP12 expression, and 15 discs were analysed
by western blot and zymography in order to detect pro- and active
MMP12.Objectives
Methods
The use of ultrasound in the diagnosis and management of disorders of the tendo Achillis is discussed. Some of the pathological processes which occur in Achilles tendinopathy can be identified by ultrasound, which may also be used to direct local treatment.
Damage to the cartilage of the distal radioulnar
joint frequently leads to pain and limitation of movement, therefore repair
of this joint cartilage would be highly desirable. The purpose of
this study was to investigate the fixation of scaffold in cartilage
defects of this joint as part of matrix-assisted regenerative autologous
cartilage techniques. Two techniques of fixation of collagen scaffolds,
one involving fibrin glue alone and one with fibrin glue and sutures, were
compared in artificially created cartilage defects of the distal
radioulnar joint in a human cadaver. After being subjected to continuous
passive rotation, the methods of fixation were evaluated for cover
of the defect and pull out force. No statistically significant differences were found between the
two techniques for either cover of the defect or integrity of the
scaffold. However, a significantly increased mean pull out force
was found for the combined procedure, 0.665 N (0.150 to 1.160) This suggests that although successful fixation of a collagen
type I/III scaffold in a distal radioulnar joint cartilage defect
is feasible with both forms of fixation, fixation with glue and
sutures is preferable. Cite this article:
Intrapelvic migration of the acetabular component of a total hip replacement, with severe acetabular destruction making reconstruction impossible, is very rare. We present a patient in whom the component was removed using a laparotomy and a transperitoneal approach with subsequent salvage using a saddle prosthesis and a total femoral replacement.
Nanometre-sized particles of ultra-high molecular weight polyethylene have been identified in the lubricants retrieved from hip simulators. Tissue samples were taken from seven failed Charnley total hip replacements, digested using strong alkali and analysed using high-resolution field emission gun-scanning electron microscopy to determine whether nanometre-sized particles of polyethylene debris were generated We isolated nanometre-sized particles from the retrieved tissue samples. The smallest identified was 30 nm and the majority were in the 0.1 μm to 0.99 μm size range. Particles in the 1.0 μm to 9.99 μm size range represented the highest proportion of the wear volume of the tissue samples, with 35% to 98% of the total wear volume comprised of particles of this size. The number of nanometre-sized particles isolated from the tissues accounted for only a small proportion of the total wear volume. Further work is required to assess the biological response to nanometre-sized polyethylene particles.
Systemic mastocytosis is a rare condition that often involves the bone marrow. We report the case of a patient with systemic mastocytosis who underwent total hip replacement. Technical difficulties encountered during the procedure included a narrow medullary canal and abnormally hard bone, later confirmed by laboratory measurements. Follow-up at five years showed a good clinical and radiological outcome.
Platelet-derived growth factor (PDGF) is known
to stimulate osteoblast or osteoprogenitor cell activity. We investigated
the effect of locally applied PDGF from poly- These results indicate that local application of PDGF from biodegradable
PDLLA-coated implants significantly accelerates fracture healing
in experimental animals. Further development may help fracture healing
in the clinical situation.
The Oxford hip score (OHS) is a 12-item questionnaire designed
and developed to assess function and pain from the perspective of
patients who are undergoing total hip replacement (THR). The OHS
has been shown to be consistent, reliable, valid and sensitive to
clinical change following THR. It has been translated into different
languages, but no adequately translated, adapted and validated Danish
language version exists. The OHS was translated and cross-culturally adapted into Danish
from the original English version, using methods based on best-practice
guidelines. The translation was tested for psychometric quality
in patients drawn from a cohort from the Danish Hip Arthroplasty
Register (DHR).Objectives
Methods
This preliminary study evaluates a combination
of bone morphogenetic protein (BMP)-7 and non-vascularised autologous
fibular grafting (AFG) for the treatment of osteonecrosis of the
femoral head. BMP-7/AFG combination was applied in seven pre-collapse femoral
heads (five Steinberg stage II, two stage III) in six patients.
Pre- and post-operative evaluation included clinical (Harris hip
score (HHS), visual analogue scale (VAS) for pain) and radiological
assessment (radiographs, quantitative CT) at a mean follow-up of
4 years (2 to 5.5). A marked improvement of function (mean HHS increase of 49.2)
and decrease of pain level (mean VAS decrease of 5) as well as retention
of the sphericity of the femoral head was noted in five hips at
the latest follow-up, while signs of consolidation were apparent
from the third post-operative month. One patient (two hips) required
bilateral total hip replacement at one year post-operatively. In
the series as a whole, quantitative-CT evaluation revealed similar densities
between affected and normal bone. Heterotopic ossification was observed
in four hips, without compromise of the clinical outcome. In this limited series AFG/BMP-7 combination proved a safe and
effective method for the treatment of femoral head osteonecrosis,
leading to early consolidation of the AFG and preventing collapse
in five of seven hips, while the operative time and post-operative
rehabilitation period were much shorter compared with free vascularised fibular
grafts. Cite this article:
Between 2002 and 2008, 130 consecutive ankles were replaced with an hydroxyapatite (HA) and titanium-HA-coated Ankle Evolutive System total ankle prosthesis. Plain radiographs were analysed by two independent observers. Osteolytic lesions were classified by their size and location, with cavities >
10 mm in diameter considered to be ‘marked’. CT scanning was undertaken in all patients with marked osteolysis seen on the plain radiographs. Osteolytic lesions were seen on the plain films in 48 (37%) and marked lesions in 27 (21%) ankles. The risk for osteolysis was found to be 3.1 (95% confidence interval 1.6 to 5.9) times higher with implants with Ti-HA porous coating. Care should be taken with ankle arthroplasty until more is known about the reasons for these severe osteolyses.
