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
To compare the structural durability of hydroxyapatite-tricalcium
phosphate (HATCP) to autologous iliac crest bone graft in calcaneal
lengthening osteotomy (CLO) for pes planovalgus in childhood. We present the interim results of ten patients (HATCP, n = 6
and autograft, n = 5) with a mean age of 11.5 years (8.2 to 14.2)
from a randomised controlled non-inferiority trial with six months
follow-up. The primary outcome was the stability of the osteotomy
as measured by radiostereometric analysis. A non-inferiority margin
of ≤ 2 mm osteotomy compression was set.Aims
Patients and Methods
The bony shoulder stability ratio (BSSR) allows for quantification of the bony stabilisers Four polyethylene balls (radii: 19.1 mm to 38.1 mm) were used to mould four fitting sockets in four different depths (3.2 mm to 19.1mm). The SR was measured in biomechanical congruent and incongruent experimental series. The experimental SR of a congruent system was compared with the calculated SR based on the BSSR approach. Differences in SR between congruent and incongruent experimental conditions were quantified. Finally, the experimental SR was compared with either calculated SR based on the socket concavity or plastic ball radius.Objectives
Methods
The surgical management of ankle arthritis with tibiotalar arthrodesis
is known to alter gait, as compared with normal ankles. The purpose
of this study was to assess post-operative gait function with gait
before arthrodesis. We prospectively studied 20 patients who underwent three-dimensional
gait analysis before and after tibiotalar arthrodesis. Cadence,
step length, walking velocity and total support time were assessed.
Kinetic parameters, including the moment and power of the ankle
in the sagittal plane and hip power were also recorded.Aims
Patients and Methods
To elucidate the effects of age on the expression levels of the receptor activator of the nuclear factor-κB ligand (RANKL) and osteoclasts in the periodontal ligament during orthodontic mechanical loading and post-orthodontic retention. The study included 20 male Sprague-Dawley rats, ten in the young group (aged four to five weeks) and ten in the adult group (aged 18 to 20 weeks). In each rat, the upper-left first molar was subjected to a seven-day orthodontic force loading followed by a seven-day retention period. The upper-right first molar served as a control. The amount of orthodontic tooth movement was measured after seven-day force application and seven-day post-orthodontic retention. The expression levels of RANKL and the tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts were evaluated on day 7 (end of mechanical force loading) and day 14 (after seven days of post-orthodontic retention). Statistical analysis was performed using the Objectives
Materials and Methods
We investigated whether blood metal ion levels could effectively
identify patients with bilateral Birmingham Hip Resurfacing (BHR)
implants who have adverse reactions to metal debris (ARMD). Metal ion levels in whole blood were measured in 185 patients
with bilateral BHRs. Patients were divided into those with ARMD
who either had undergone a revision for ARMD or had ARMD on imaging
(n = 30), and those without ARMD (n = 155). Receiver operating characteristic
analysis was used to determine the optimal thresholds of blood metal
ion levels for identifying patients with ARMD.Aims
Patients and Methods
The spinopelvic relationship (including pelvic incidence) has been shown to influence pelvic orientation, but its potential association with femoroacetabular impingement has not been thoroughly explored. The purpose of this study was to prove the hypothesis that decreasing pelvic incidence is associated with increased risk of cam morphology. Two matching cohorts were created from a collection of cadaveric specimens with known pelvic incidences: 50 subjects with the highest pelvic incidence (all subjects > 60°) and 50 subjects with the lowest pelvic incidence (all subjects < 35°). Femoral version, acetabular version, and alpha angles were directly measured from each specimen bilaterally. Cam morphology was defined as alpha angle > 55°. Differences between the two cohorts were analysed with a Student’s Objectives
Methods
Pain catastrophising is an adverse coping mechanism,
involving an exaggerated response to anticipated or actual pain. The purpose of this study was to investigate the influence of
pain ‘catastrophising’, as measured using the pain catastrophising
scale (PCS), on treatment outcomes after surgery for lumbar spinal
stenosis (LSS). A total of 138 patients (47 men and 91 women, mean age 65.9;
45 to 78) were assigned to low (PCS score <
25, n = 68) and high
(PCS score ≥ 25, n = 70) PCS groups. The primary outcome measure
was the Oswestry Disability Index (ODI) 12 months after surgery.
Secondary outcome measures included the ODI and visual analogue
scale (VAS) for back and leg pain, which were recorded at each assessment
conducted during the 12-month follow-up period The overall changes in the ODI and VAS for back and leg pain
over a 12-month period were significantly different between the
groups (ODI, p <
0.001; VAS for back pain, p <
0.001; VAS
for leg pain, p = 0.040). The ODI and VAS for back and leg pain
significantly decreased over time after surgery in both groups (p
<
0.001 for all three variables). The patterns of change in the
ODI and VAS for back pain during the follow-up period significantly
differed between the two groups, suggesting that the PCS group is
a potential treatment moderator. However, there was no difference
in the ODI and VAS for back and leg pain between the low and high
PCS groups 12 months after surgery. In terms of minimum clinically important differences in ODI scores
(12.8), 22 patients (40.7%) had an unsatisfactory surgical outcome
in the low PCS group and 16 (32.6%) in the high PCS group. There
was no statistically significant difference between the two groups
(p = 0.539). Pre-operative catastrophising did not always result in a poor
outcome 12 months after surgery, which indicates that this could
moderate the efficacy of surgery for LSS. Cite this article:
The purpose of this study was to evaluate the
change in sagittal tibiotalar alignment after total ankle arthroplasty (TAA)
for osteoarthritis and to investigate factors affecting the restoration
of alignment. This retrospective study included 119 patients (120 ankles) who
underwent three component TAA using the Hintegra prosthesis. A total
of 63 ankles had anterior displacement of the talus before surgery
(group A), 49 had alignment in the normal range (group B), and eight
had posterior displacement of the talus (group C). Ankles in group
A were further sub-divided into those in whom normal alignment was
restored following TAA (41 ankles) and those with persistent displacement
(22 ankles). Radiographic and clinical results were assessed. Pre-operatively, the alignment in group A was significantly more
varus than that in group B, and the posterior slope of the tibial
plafond was greater (p <
0.01 in both cases). The posterior slope
of the tibial component was strongly associated with restoration
of alignment: ankles in which the alignment was restored had significantly
less posterior slope (p <
0.001). An anteriorly translated talus was restored to a normal position
after TAA in most patients. We suggest that surgeons performing
TAA using the Hintegra prosthesis should aim to insert the tibial
component at close to 90° relative to the axis of the tibia, hence
reducing posterior soft-tissue tension and allowing restoration
of normal tibiotalar alignment following surgery. Cite this article:
Compartment syndrome results from increased intra-compartmental
pressure (ICP) causing local tissue ischaemia and cell death, but
the systemic effects are not well described. We hypothesised that
compartment syndrome would have a profound effect not only on the affected
limb, but also on remote organs. Using a rat model of compartment syndrome, its systemic effects
on the viability of hepatocytes and on inflammation and circulation
were directly visualised using intravital video microscopy.Aims
Methods
This study reports on the first 150 consecutive
Oxford cementless unicompartmental knee arthroplasties (UKA) performed
in an independent centre (126 patients). All eligible patients had
functional scores (Oxford knee score and high activity arthroplasty
score) recorded pre-operatively and at two- and five-years of follow-up. Fluoroscopically
aligned radiographs were taken at five years and analysed for any
evidence of radiolucent lines (RLLs), subsidence or loosening. The
mean age of the cohort was 63.6 years (39 to 86) with 81 (53.1%)
males. Excellent functional scores were maintained at five years
and there were no progressive RLLs demonstrated on radiographs.
Two patients underwent revision to a total knee arthroplasty giving
a revision rate of 0.23/100 (95% confidence interval 0.03 to 0.84)
component years with overall component survivorship of 98.7% at
five years. There were a further four patients who underwent further
surgery on the same knee, two underwent bearing exchanges for dislocation
and two underwent lateral UKAs for disease progression. This was
a marked improvement from other UKAs reported in New Zealand Joint
Registry data and supports the designing centre’s early results. Cite this article:
There is a paucity of information on the pre-operative coronal
imbalance in patients with degenerative lumbar scoliosis (DLS) and
its influence on surgical outcomes. A total of 284 DLS patients were recruited into this study, among
whom 69 patients were treated surgically and the remaining 215 patients
conservatively Patients were classified based on the coronal balance
distance (CBD): Type A, CBD <
3 cm; Type B, CBD >
3 cm and C7
Plumb Line (C7PL) shifted to the concave side of the curve; Type
C, CBD >
3 cm and C7PL shifted to the convex side.Aims
Patients and Methods
Tissue responses to debris formed by abrasion of polymethylmethacrylate
(PMMA) spacers at two-stage revision arthroplasty for prosthetic
joint infection are not well described. We hypothesised that PMMA
debris induces immunomodulation in periprosthetic tissues. Samples of tissue were taken during 35 two-stage revision arthroplasties
(nine total hip and 26 total knee arthroplasties) in patients whose
mean age was 67 years (44 to 85). Fourier transform infrared microscopy
was used to confirm the presence of PMMA particles. Histomorphometry
was performed using Sudan Red and Haematoxylin-Eosin staining.
CD-68, CD-20, CD-11(c), CD-3 and IL-17 antibodies were used to immunophenotype
the inflammatory cells. All slides were scored semi-quantitatively
using the modified Willert scoring system.Aims
Patients and Methods
Our aim was to compare kinematic with mechanical alignment in
total knee arthroplasty (TKA). We performed a prospective blinded randomised controlled trial
to compare the functional outcome of patients undergoing TKA in
mechanical alignment (MA) with those in kinematic alignment (KA).
A total of 71 patients undergoing TKA were randomised to either
kinematic (n = 36) or mechanical alignment (n = 35). Pre- and post-operative
hip-knee-ankle radiographs were analysed. The knee injury and osteoarthritis
outcome score (KOOS), American Knee Society Score, Short Form-36,
Euro-Qol (EQ-5D), range of movement (ROM), two minute walk, and timed
up and go tests were assessed pre-operatively and at six weeks,
three and six months and one year post-operatively.Aims
Patients and Methods
We wished to compare the clinical outcome, as assessed by questionnaires
and the rate of complications, in total knee arthroplasty (TKA)
undertaken with patient-matched positioning guides (PMPGs) or conventional
instruments. A total of 180 patients (74 men, 106 women; mean age 67 years)
were included in a multicentre, adequately powered, double-blind,
randomised controlled trial. The mean follow-up was 44 months (24
to 57).Aims
Patients and Methods
This study aimed to characterise and qualitatively grade the severity of the corrosion particles released into the hip joint following taper corrosion. The 26 cases examined were CoC/ABG Modular (n = 13) and ASR/SROM (n = 13). Blood serum metal ion levels were collected before and after revision surgery. The haematoxylin and eosin tissue sections were graded on the presence of fibrin exudates, necrosis, inflammatory cells and corrosion products. The corrosion products were identified based on visible observation and graded on abundance. Two independent observers blinded to the clinical patient findings scored all cases. Elemental analysis was performed on corrosion products within tissue sections. X-Ray diffraction was used to identify crystalline structures present in taper debris.Objectives
Methods
Fractures of the distal femur are an important cause of morbidity.
Their optimal management remains controversial. Contemporary implants
include angular-stable anatomical locking plates and locked intramedullary
nails (IMNs). We compared the long-term patient-reported functional
outcome of fixation of fractures of the distal femur using these
two methods of treatment. A total of 297 patients were retrospectively identified from
a State-wide trauma registry in Australia: 195 had been treated
with a locking plate and 102 with an IMN. Baseline characteristics
of the patients and their fractures were recorded. Health-related
quality-of-life, functional and radiographic outcomes were compared
using mixed effects regression models at six months and one year.Aims
Patients and Methods
We have observed clinical cases where bone is formed in the overlaying muscle covering surgically created bone defects treated with a hydroxyapatite/calcium sulphate biomaterial. Our objective was to investigate the osteoinductive potential of the biomaterial and to determine if growth factors secreted from local bone cells induce osteoblastic differentiation of muscle cells. We seeded mouse skeletal muscle cells C2C12 on the hydroxyapatite/calcium sulphate biomaterial and the phenotype of the cells was analysed. To mimic surgical conditions with leakage of extra cellular matrix (ECM) proteins and growth factors, we cultured rat bone cells ROS 17/2.8 in a bioreactor and harvested the secreted proteins. The secretome was added to rat muscle cells L6. The phenotype of the muscle cells after treatment with the media was assessed using immunostaining and light microscopy.Objectives
Materials and Methods
Depression can significantly affect quality of life and is associated
with higher rates of medical comorbidities and increased mortality
following surgery. Although depression has been linked to poorer
outcomes following orthopaedic trauma, total joint arthroplasty
and spinal surgery, we wished to examine the impact of depression
in elective total shoulder arthroplasty (TSA) as this has not been
previously explored. The United States Nationwide Inpatient Sample (NIS) was used
to identify patients undergoing elective TSA over a ten-year period.
Between 2002 and 2012, 224 060 patients underwent elective TSA.Aims
Patients and Methods
Hip resurfacing arthroplasty (HRA) is an alternative to conventional
total hip arthroplasty for patients with osteonecrosis (ON) of the
femoral head. Our aim was to report the long-term outcome of HRA,
which is not currently known. Long-term survivorship, clinical scores and radiographic results
for 82 patients (99 hips) treated with HRA for ON over a period
of 18 years were reviewed retrospectively. The mean age of the 67
men and 15 women at the time of surgery was 40.8 years (14 to 64).
Patients were resurfaced regardless of the size of the osteonecrotic
lesion.Aims
Patients and Methods
