This study investigated the influence of body mass index (BMI)
on the post-operative fall in the level of haemoglobin (Hb), length
of hospital stay (LOS), 30-day re-admission rate, functional outcome
and quality of life, two years after total knee arthroplasty (TKA). A total of 7733 patients who underwent unilateral primary TKA
between 2001 and 2010 were included. The mean age was 67 years (30
to 90). There were 1421 males and 6312 females. The patients were
categorised into three groups: BMI <
25.0 kg/m2 (normal);
BMI between 25.0 and 39.9 kg/m2 (obese); and BMI ≥ 40.0
kg/m2 (morbidly obese).Aims
Patients and Methods
The aim of this study was to examine the results of revision
total knee arthroplasty (TKA) undertaken for stiffness in the absence
of sepsis or loosening. We present the results of revision surgery for stiff TKA in 48
cases (35 (72.9%) women and 13 (27.1%) men). The mean age at revision
surgery was 65.5 years (42 to 83). All surgeries were performed
by a single surgeon. Stiffness was defined as an arc of flexion
of <
70° or a flexion contracture of >
15°. The changes in the
range of movement (ROM) and the Western Ontario and McMasters Osteoarthritis
index scores (WOMAC) were recorded.Aims
Patients and Methods
In patients undergoing medial opening wedge high tibial osteotomy
(MOWHTO), soft tissue opening on the medial side of the knee is
difficult to predict. When the load bearing axis is corrected beyond
a certain point, the knee joint tilts open on the medial side. We
therefore hypothesised that there is a tipping point and defined
this as the coronal hypomochlion. In this prospective study of 150 navigated MOWHTOs (144 consecutive
patients), data were collected before surgery and at three months
post-operatively. In order to calculate the hypomochlion, we compared
the respective changes to the joint line convergence angle (JLCA)
with the post-operative axis of the leg. The change to the medial proximal
tibial angle accounts for only about 80% of the change to the femorotibial
angle; 20% of the correction can therefore be attributed to non-osseous,
soft-tissue changes.Aims
Patients and Methods
To examine the rates of hamstring graft salvage with arthroscopic
debridement of infected anterior cruciate ligament (ACL) reconstruction
as reported in the literature and discuss functional outcomes. A search was performed without language restriction on PubMed,
EMBASE, Ovid, CINAHL and Cochrane Register of Controlled Trials
(CENTRAL) databases from their inception to April 2015. We identified
147 infected hamstring grafts across 16 included studies. Meta-analysis
was performed using a random-effects model to estimate the overall
graft salvage rate, incorporating two different definitions of graft
salvage.Aims
Materials and Methods
Normal sagittal spine-pelvis-lower extremity alignment is crucial in humans for maintaining an ergonomic upright standing posture, and pathogenesis in any segment leads to poor balance. The present study aimed to investigate how this sagittal alignment can be affected by severe knee osteoarthritis (KOA), and whether associated changes corresponded with symptoms of lower back pain (LBP) in this patient population. Lateral radiograph films in an upright standing position were obtained from 59 patients with severe KOA and 58 asymptomatic controls free from KOA. Sagittal alignment of the spine, pelvis, hip and proximal femur was quantified by measuring several radiographic parameters. Global balance was accessed according to the relative position of the C7 plumb line to the sacrum and femoral heads. The presence of chronic LBP was documented. Comparisons between the two groups were carried by independent samples Objectives
Methods
The purpose of the present study was to examine the long-term
fixation of a cemented fixed-bearing polished titanium tibial baseplate
(Genesis ll). Patients enrolled in a previous two-year prospective trial (n
= 35) were recalled at ten years. Available patients (n = 15) underwent
radiostereometric analysis (RSA) imaging in a supine position using
a conventional RSA protocol. Migration of the tibial component in
all planes was compared between initial and ten-year follow-up.
Outcome scores including the Knee Society Score, Western Ontario
and McMaster Universities Arthritis Index, 12-item Short Form Health
Survey, Forgotten Joint Score, and University of California, Los
Angeles Activity Score were recorded.Aims
Patients and Methods
In arthritis of the varus knee, a high tibial
osteotomy (HTO) redistributes load from the diseased medial compartment
to the unaffected lateral compartment. We report the outcome of 36 patients (33 men and three women)
with 42 varus, arthritic knees who underwent HTO and dynamic correction
using a Garches external fixator until they felt that normal alignment
had been restored. The mean age of the patients was 54.11 years
(34 to 68). Normal alignment was achieved at a mean 5.5 weeks (3
to 10) post-operatively. Radiographs, gait analysis and visual analogue
scores for pain were measured pre- and post-operatively, at one
year and at medium-term follow-up (mean six years; 2 to 10). Failure
was defined as conversion to knee arthroplasty. Pre-operative gait analysis divided the 42 knees into two equal
groups with high (17 patients) or low (19 patients) adductor moments.
After correction, a statistically significant (p <
0.001, At final follow-up, after a mean of 15.9 years (12 to 20), there
was a survivorship of 59% (95% CI 59.6 to 68.9) irrespective of
adductor moment group, with a mean time to conversion to knee arthroplasty
of 9.5 years (3 to 18; 95% confidence interval ± 2.5). HTO remains a useful option in the medium-term for the treatment
of medial compartment osteoarthritis of the knee but does not last
in the long-term. Cite this article:
Previous genome-wide association studies (GWAS) have reported significant association of the single nucleotide polymorphism (SNP) rs8044769 in the fat mass and obesity-associated gene (FTO) with osteoarthritis (OA) risk in European populations. However, these findings have not been confirmed in Chinese populations. We systematically genotyped rs8044769 and evaluated the association between the genetic variants and OA risk in a case-controlled study including 196 OA cases and 442 controls in a northern Chinese population. Genotyping was performed using the Sequenom MassARRAY iPLEX platform.Objectives
Methods
Nail patella syndrome (NPS) is a skeletal dysplasia with patellofemoral
dysfunction as a key symptom. We present the first in-depth radiological
evaluation of the knee in a large series of NPS patients and describe
the typical malformations. Conventional radiological examination of 95 skeletally mature
patients with NPS was performed. Patellar morphology was classified
according to the Wiberg classification as modified by Baumgartl
and Ficat criteria, and trochlear shape was classified according
to the Dejour classification.Aim
Patients and Methods
The pre-operative level of haemoglobin is the strongest predictor
of the peri-operative requirement for blood transfusion after total
knee arthroplasty (TKA). There are, however, no studies reporting
a value that could be considered to be appropriate pre-operatively. This study aimed to identify threshold pre-operative levels of
haemoglobin that would predict the requirement for blood transfusion
in patients who undergo TKA. Analysis of receiver operator characteristic (ROC) curves of
2284 consecutive patients undergoing unilateral TKA was used to
determine gender specific thresholds predicting peri-operative transfusion
with the highest combined sensitivity and specificity (area under
ROC curve 0.79 for males; 0.78 for females).Aims
Patients and Methods
We explored the literature surrounding whether
allergy and hypersensitivity has a clinical basis for implant selection
in total knee arthroplasty (TKA). In error, the terms hypersensitivity
and allergy are often used synonymously. Although a relationship
is present, we could not find any evidence of implant failure due
to allergy. There is however increasing basic science that suggests
a link between loosening and metal ion production. This is not an
allergic response but is a potential problem. With a lack of evidence
logically there can be no justification to use ‘hypoallergenic’
implants in patients who have pre-existing skin sensitivity to the
metals used in TKA. Cite this article:
Throughout the 20th Century, it has been postulated that the knee moves on the basis of a four-bar link mechanism composed of the cruciate ligaments, the femur and the tibia. As a consequence, the femur has been thought to roll back with flexion, and total knee arthroplasty (TKA) prostheses have been designed on this basis. Recent work, however, has proposed that at a position of between 0° and 120° the medial femoral condyle does not move anteroposteriorly whereas the lateral femoral condyle tends, but is not obliged, to roll back – a combination of movements which equates to tibial internal/ femoral external rotation with flexion. The aim of this paper was to assess if the articular geometry of the GMK Sphere TKA could recreate the natural knee movements The pattern of knee movement was studied in 15 patients (six male: nine female; one male with bilateral TKAs) with 16 GMK Sphere implants, at a mean age of 66 years (53 to 76) with a mean BMI of 30 kg/m2 (20 to 35). The motions of all 16 knees were observed using pulsed fluoroscopy during a number of weight-bearing and non-weight-bearing static and dynamic activities.Objectives
Methods
The aim of this study was to identify risk factors for prosthetic
joint infection (PJI) following total knee arthroplasty (TKA). The New Zealand Joint Registry database was analysed, using revision
surgery for PJI at six and 12 months after surgery as primary outcome
measures. Statistical associations between revision for infection,
with common and definable surgical and patient factors were tested.Aims
Patients and Methods
There is conflicting evidence about the benefit
of using corticosteroid in periarticular injections for pain relief
after total knee arthroplasty (TKA). We carried out a double-blinded,
randomised controlled trial to assess the efficacy of using corticosteroid
in a periarticular injection to control pain after TKA. A total of 77 patients, 67 women and ten men, with a mean age
of 74 years (47 to 88) who were about to undergo unilateral TKA
were randomly assigned to have a periarticular injection with or
without corticosteroid. The primary outcome was post-operative pain
at rest during the first 24 hours after surgery, measured every
two hours using a visual analogue pain scale score. The cumulative
pain score was quantified using the area under the curve. The corticosteroid group had a significantly lower cumulative
pain score than the no-corticosteroid group during the first 24
hours after surgery (mean area under the curve 139, 0 to 560, and
264, 0 to 1460; p = 0.024). The rate of complications, including
surgical site infection, was not significantly different between
the two groups up to one year post-operatively. The addition of corticosteroid to the periarticular injection
significantly decreased early post-operative pain. Further studies
are needed to confirm the safety of corticosteroid in periarticular
injection.
Cite this article:
Analysis of the morphology of the distal femur, and by extension
of the femoral components in total knee arthroplasty (TKA), has
largely been related to the aspect ratio, which represents the width
of the femur. Little is known about variations in trapezoidicity
(i.e. whether the femur is more rectangular or more trapezoidal).
This study aimed to quantify additional morphological characteristics
of the distal femur and identify anatomical features associated
with higher risks of over- or under-sizing of components in TKA. We analysed the shape of 114 arthritic knees at the time of primary
TKA using the pre-operative CT scans. The aspect ratio and trapezoidicity
ratio were quantified, and the post-operative prosthetic overhang
was calculated. We compared the morphological characteristics with
those of 12 TKA models.Aims
Methods
Patient specific instrumentation (PSI) uses advanced
imaging of the knee (CT or MRI) to generate individualised cutting
blocks aimed to make the procedure of total knee arthroplasty (TKA)
more accurate and efficient. However, in this era of healthcare
cost consciousness, the value of new technologies needs to be critically
evaluated. There have been several comparative studies looking at
PSI Cite this article:
A key to the success of revision total knee arthroplasty
(TKA) is a safe surgical approach using an exposure that minimises
complications. In most patients, a medial parapatellar arthrotomy
with complete synovectomy is sufficient. If additional exposure
is needed, a quadriceps snip performed through the quadriceps tendon
often provides the additional exposure required. It is simple to
perform and does not alter the post-operative rehabilitative protocol.
In rare cases, in which additional exposure is needed, or when removal
of a cemented long-stemmed tibial component is required, a tibial
tubercle osteotomy (TTO) may be used. Given the risk of post-operative
extensor lag, a V-Y quadricepsplasty is rarely indicated and usually
considered only if TTO is not possible. Cite this article:
Total knee arthroplasty (TKA) is a cost effective
and extremely successful operation. As longevity increases, the demand
for primary TKA will continue to rise. The success and survivorship
of TKAs are dependent on the demographics of the patient, surgical
technique and implant-related factors. Currently the risk of failure of a TKA requiring revision surgery
ten years post-operatively is 5%. The most common indications for revision include aseptic loosening
(29.8%), infection (14.8%), and pain (9.5%). Revision surgery poses
considerable clinical burdens on patients and financial burdens
on healthcare systems. We present a current concepts review on the epidemiology of failed
TKAs using data from worldwide National Joint Registries. Cite this article:
Oxidised zirconium was introduced as a material for femoral components
in total knee arthroplasty (TKA) as an attempt to reduce polyethylene
wear. However, the long-term survival of this component is not known. We performed a retrospective review of a prospectively collected
database to assess the ten year survival and clinical and radiological
outcomes of an oxidised zirconium total knee arthroplasty with the
Genesis II prosthesis. The Western Ontario and McMaster Universities Osteoarthritis
Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS)
and a patient satisfaction scale were used to assess outcome.Aims
Methods
The term mid-flexion instability has entered
the orthopaedic literature as a concept, but has not been confirmed
as a distinct clinical entity. The term is used freely, sometimes
as a synonym for flexion instability. However, the terms need to
be clearly separated. A cadaver study published in 1990 associated
joint line elevation with decreased stability at many angles of
flexion, but that model was not typical of clinical scenarios. The
literature is considered and it is proposed that the more common
entity of an uncorrected flexion contracture after a measured resection arthroplasty
technique is more likely to produce clinical findings that suggest
instability mid-flexion. It is proposed that the clinical scenario encountered is generalised
instability, with the appearance of stability in full extension
from tight posterior structures. This paper seeks to clarify whether mid-flexion instability exists
as an entity distinct from other commonly recognised forms of instability. Cite this article:
