Polyethylene wear debris can cause osteolysis
and the failure of total hip arthroplasty. We present the five-year
wear rates of a highly cross-linked polyethylene (X3) bearing surface
when used in conjunction with a 36 mm ceramic femoral head. This was a prospective study of a cohort of 100 THAs in 93 patients.
Pain and activity scores were measured pre- and post-operatively.
Femoral head penetration was measured at two months, one year, two
years and at five years using validated edge-detecting software
(PolyWare Auto). At a mean of 5.08 years (3.93 to 6.01), 85 hips in 78 patients
were available for study. The mean age of these patients was 59.08
years (42 to 73, the mean age of males (n = 34) was 59.15 years,
and females (n = 44) was 59.02 years). All patients had significant
improvement in their functional scores (p <
0.001). The steady
state two-dimensional linear wear rate was 0.109 mm/year. The steady
state volumetric wear rate was 29.61 mm3/year. No significant
correlation was found between rate of wear and age (p = 0.34), acetabular
component size (p = 0.12) or clinical score (p = 0.74). Our study shows low steady state wear rates at five years in
X3 highly cross-linked polyethylene in conjunction with a 36 mm
ceramic femoral head. The linear wear rate was almost identical
to the osteolysis threshold of 0.1 mm/year recommended in the literature. Cite this article:
To validate the English language Forgotten Joint Score-12 (FJS-12)
as a tool to evaluate the outcome of hip and knee arthroplasty in
a United Kingdom population. All patients undergoing surgery between January and August 2014
were eligible for inclusion. Prospective data were collected from
205 patients undergoing total hip arthroplasty (THA) and 231 patients
undergoing total knee arthroplasty (TKA). Outcomes were assessed
with the FJS-12 and the Oxford Hip and Knee Scores (OHS, OKS) pre-operatively,
then at six and 12 months post-operatively. Internal consistency,
convergent validity, effect size, relative validity and ceiling
effects were determined.Aims
Patients and Methods
Transtrochanteric rotational osteotomy (TRO) is performed for
young patients with non-traumatic osteonecrosis of the femoral head
(ONFH) to preserve the hip. We aimed to investigate the long-term
outcomes and the risk factors for failure 15 years after this procedure. This study included 95 patients (111 hips) with a mean age of
40 years (21 to 64) who underwent TRO for ONFH. The mean follow-up
was 18.2 years (3 to 26). Kaplan–Meier survivorship analyses were
performed with conversion to total hip arthroplasty (THA) and radiological
failure due to secondary collapse of the femoral head or osteoarthritic changes
as the endpoint. Multivariate analyses were performed to assess
risk factors for each outcome.Aims
Patients and Methods
Rates of mortality as high as 25% to 30% have been described
following fractures of the odontoid in the elderly population. The
aim of this study was to examine whether easily identifiable variables
present on admission are associated with mortality. A consecutive series of 83 elderly patients with a fracture of
the odontoid following a low-impact injury was identified retrospectively.
Data that were collected included demographics, past medical history
and the results of blood tests on admission. Radiological investigations
were used to assess the Anderson and D’Alonzo classification and
displacement of the fracture. The mean age was 82.9 years (65 to
101). Most patients (66; 79.5%) had a type 2 fracture. An associated
neurological deficit was present in 11 (13.3%). All were treated
conservatively; 80 (96.4%) with a hard collar and three (3.6%) with
halo vest immobilisation.Aims
Patients and Methods
Assessment of skeletal age is important in children’s
orthopaedics. We compared two simplified methods used in the assessment
of skeletal age. Both methods have been described previously with
one based on the appearance of the epiphysis at the olecranon and
the other on the digital epiphyses. We also investigated the influence
of assessor experience on applying these two methods. Our investigation was based on the anteroposterior left hand
and lateral elbow radiographs of 44 boys (mean: 14.4; 12.4 to 16.1
) and 78 girls (mean: 13.0; 11.1 to14.9) obtained during the pubertal
growth spurt. A total of nine observers examined the radiographs
with the observers assigned to three groups based on their experience (experienced,
intermediate and novice). These raters were required to determined
skeletal ages twice at six-week intervals. The correlation between
the two methods was determined per assessment and per observer groups. Interclass
correlation coefficients (ICC) evaluated the reproducibility of
the two methods. The overall correlation between the two methods was r = 0.83
for boys and r = 0.84 for girls. The correlation was equal between
first and second assessment, and between the observer groups (r ≥ 0.82).
There was an equally strong ICC for the assessment effect (ICC ≤ 0.4%)
and observer effect (ICC ≤ 3%) for each method. There was no significant
(p <
0.05) difference between the levels of experience. The two methods are equally reliable in assessing skeletal maturity.
The olecranon method offers detailed information during the pubertal
growth spurt, while the digital method is as accurate but less detailed,
making it more useful after the pubertal growth spurt once the olecranon
has ossified. Cite this article:
It has been suggested that cemented fixation of total hip arthroplasty
(THA) is associated with an increased peri-operative mortality compared
with cementless THA. Our aim was to investigate this through a nationwide
matched cohort study adjusting for age, comorbidity, and socioeconomic
background. A total of 178 784 patients with osteoarthritis who underwent
either cemented or cementless THA from the Swedish Hip Arthroplasty
Register were matched with 862 294 controls from the general population.
Information about the causes of death, comorbidities, and socioeconomic
background was obtained. Mortality within the first 90 days after
the operation was the primary outcome measure.Aims
Patients and Methods
The aim of the study was to develop a quantitative scoring system
to predict whether a large-to-massive rotator cuff tear was arthroscopically
reparable prior to surgery. We conducted a retrospective review of the pre-operative MR imaging
and surgical records of 87 patients (87 shoulders) who underwent
arthroscopic repair of a large-to-massive rotator cuff tear. Patients
were divided into two groups, based on the surgical outcome of the
repair. Of the 87 patients, 53 underwent complete repair (Group
I) and 34 an incomplete repair (Group II). Pre-operative MR images
were reviewed to quantify several variables. Between-group differences
were evaluated and multiple logistic regression analysis was used
to calculate the predictive value of significant variables. The
reparability index (RI) was constructed using the odds ratios of
significant variables and a receiver operating characteristic curve
analysis performed to identify the optimal RI cutoff to differentiate
between the two groups.Aims
Patients and 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:
Up to 40% of unicompartmental knee arthroplasty (UKA) revisions are performed for unexplained pain which may be caused by elevated proximal tibial bone strain. This study investigates the effect of tibial component metal backing and polyethylene thickness on bone strain in a cemented fixed-bearing medial UKA using a finite element model (FEM) validated experimentally by digital image correlation (DIC) and acoustic emission (AE). A total of ten composite tibias implanted with all-polyethylene (AP) and metal-backed (MB) tibial components were loaded to 2500 N. Cortical strain was measured using DIC and cancellous microdamage using AE. FEMs were created and validated and polyethylene thickness varied from 6 mm to 10 mm. The volume of cancellous bone exposed to < -3000 µε (pathological loading) and < -7000 µε (yield point) minimum principal (compressive) microstrain and > 3000 µε and > 7000 µε maximum principal (tensile) microstrain was computed.Objectives
Materials and Methods
The aim of this study was to analyse the effect of altered viewing
perspectives on the measurement of the glenopolar angle (GPA) and
the differences between these measurements made on 3D CT reconstructions
and anteroposterior (AP) scapular view radiographs. The influence of the viewing perspective on the GPA was assessed,
as were the differences in the measurements of the GPA between 3D
CT reconstructions and AP scapular view radiographs in 68 cadaveric
scapulae.Aims
Materials and Methods
In patients with osteoporosis there is always
a strong possibility that pedicle screws will loosen. This makes
it difficult to select the appropriate osteoporotic patient for
a spinal fusion. The purpose of this study was to determine the
correlation between bone mineral density (BMD) and the magnitude
of torque required to insert a pedicle screw. To accomplish this,
181 patients with degenerative disease of the lumbar spine were
studied prospectively. Each underwent dual-energy x-ray absorptiometry
(DEXA) and intra-operative measurement of the torque required to
insert each pedicle screw. The levels of torque generated in patients
with osteoporosis and osteopenia were significantly lower than those
achieved in normal patients. Positive correlations were observed between
BMD and T-value at the instrumented lumbar vertebrae, mean BMD and
mean T-value of the lumbar vertebrae, and mean BMD and mean T-value
of the proximal femur. The predictive torque (Nm) generated during pedicle
screw insertion was [-0.127 + 1.62 × (BMD at the corresponding lumbar
vertebrae)], as measured by linear regression analysis. The positive
correlation between BMD and the maximum torque required to insert
a pedicle screw suggests that pre-operative assessment of BMD may
be useful in determining the ultimate strength of fixation of a
device, as well as the number of levels that need to be fixed with
pedicle screws in patients who are suspected of having osteoporosis.
We scanned 25 left knees in healthy human subjects
using MRI. Multiplanar reconstruction software was used to take
measurements of the inferior and posterior facets of the femoral
condyles and the trochlea. A ‘basic circle’ can be defined which, in the sagittal plane,
fits the posterior and inferior facets of the lateral condyle, the
posterior facet of the medial condyle and the floor of the groove
of the trochlea. It also approximately fits both condyles in the
coronal plane (inferior facets) and the axial plane (posterior facets).
The circle fitting the inferior facet of the medial condyle in the
sagittal plane was consistently 35% larger than the other circles
and was termed the ‘medial inferior circle’. There were strong correlations
between the radii of the circles, the relative positions of the
centres of the condyles, the width of the condyles, the total knee
width and skeletal measurements including height. There was poor
correlation between the radii of the circles and the position of
the trochlea relative to the condyles. In summary, the condyles are approximately spherical except for
the inferior facet medially, which has a larger radius in the sagittal
plane. The size and position of the condyles are consistent and
change with the size of the person. However, the position of the
trochlea is variable even though its radius is similar to that of
the condyles. This information has implications for understanding
anterior knee pain and for the design of knee replacements. Cite this article:
The influence of identifiable pre-operative factors on the outcome
of eccentric rotational acetabular osteotomy (ERAO) is unknown.
We aimed to determine the factors that might influence the outcome,
in order to develop a scoring system for predicting the prognosis
for patients undergoing this procedure. We reviewed 700 consecutive ERAOs in 54 men and 646 women with
symptomatic acetabular dysplasia or early onset osteoarthritis (OA)
of the hip, which were undertaken between September 1989 and March
2013. The patients’ pre-operative background, clinical and radiological
findings were examined retrospectively. Multivariate Cox regression
analysis was performed using the time from the day of surgery to
a conversion to total hip arthroplasty (THA) as an endpoint. A risk
score was calculated to predict the prognosis for conversion to
THA, and its predictive capacity was investigated.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
Patient-specific glenoid guides (PSGs) claim an improvement in
accuracy and reproducibility of the positioning of components in
total shoulder arthroplasty (TSA). The results have not yet been
confirmed in a prospective clinical trial. Our aim was to assess
whether the use of PSGs in patients with osteoarthritis of the shoulder
would allow accurate and reliable implantation of the glenoid component. A total of 17 patients (three men and 14 women) with a mean age
of 71 years (53 to 81) awaiting TSA were enrolled in the study.
Pre- and post-operative version and inclination of the glenoid were
measured on CT scans, using 3D planning automatic software. During
surgery, a congruent 3D-printed PSG was applied onto the glenoid
surface, thus determining the entry point and orientation of the
central guide wire used for reaming the glenoid and the introduction
of the component. Manual segmentation was performed on post-operative
CT scans to compare the planned and the actual position of the entry
point (mm) and orientation of the component (°).Aims
Patients and Methods
Our aim was to investigate the predictive factors for the development
of a rebound phenomenon after temporary hemiepiphysiodesis in children
with genu valgum. We studied 37 limbs with idiopathic genu valgum who were treated
with hemiepiphyseal stapling, and with more than six months remaining
growth at removal of the staples. All children were followed until
skeletal maturity or for more than two years after removal of the
staples.Aims
Patients and Methods
Posterior tilt of the pelvis with sitting provides biological
acetabular opening. Our goal was to study the post-operative interaction
of skeletal mobility and sagittal acetabular component position. This was a radiographic study of 160 hips (151 patients) who
prospectively had lateral spinopelvic hip radiographs for skeletal
and implant measurements. Intra-operative acetabular component position
was determined according to the pre-operative spinal mobility. Sagittal
implant measurements of ante-inclination and sacral acetabular angle were
used as surrogate measurements for the risk of impingement, and
intra-operative acetabular component angles were compared with these.Aims
Materials and Methods
Flexor digitorum longus transfer and medial displacement
calcaneal osteotomy is a well-recognised form of treatment for stage
II posterior tibial tendon dysfunction. Although excellent short-
and medium-term results have been reported, the long-term outcome
is unknown. We reviewed the clinical outcome of 31 patients with
a symptomatic flexible flat-foot deformity who underwent this procedure
between 1994 and 1996. There were 21 women and ten men with a mean
age of 54.3 years (42 to 70). The mean follow-up was 15.2 years
(11.4 to 16.5). All scores improved significantly (p <
0.001).
The mean American Orthopedic Foot and Ankle Society (AOFAS) score improved
from 48.4 pre-operatively to 90.3 (54 to 100) at the final follow-up.
The mean pain component improved from 12.3 to 35.2 (20 to 40). The
mean function score improved from 35.2 to 45.6 (30 to 50). The mean
visual analogue score for pain improved from 7.3 to 1.3 (0 to 6).
The mean Short Form-36 physical component score was 40.6 ( Cite this article:
We performed a systematic review of the literature
pertaining to the functional outcomes of the surgical management
of acetabular fractures. A total of 69 articles met our inclusion
criteria, revealing that eight generic outcome instruments were
used, along with five specific instruments. The majority of studies
reported outcomes using a version of the d’Aubigne and Postel score,
which has not been validated for use in acetabular fracture. Few validated
outcome measures were reported. No psychometric testing of outcome
instruments was performed. The current assessment of outcomes in
surgery for acetabular fractures lacks scientific rigour, and does
not give reliable outcome data for either scientific comparison
or patient counselling. Take home message: The use of non-validated functional outcome
measures is a major limitation of the current literature pertaining
to surgical management of acetabular fractures; future studies should
use validated outcome measures to ensure the legitimacy of the reported
results. Cite this article:
