We assessed the long-term (more than ten-year) outcomes of the
Kudo type-5 elbow prosthesis in patients with rheumatoid arthritis
(RA). We reviewed 41 elbows (Larsen Grade IV, n = 21; Grade V, n =
20) in 31 patients with RA who had undergone a Kudo type-5 total
elbow arthroplasty (TEA) between 1994 and 2003, and had been followed
up for more than ten years. The humeral component was cementless
and the all-polyethylene ulnar component cemented in every patient. Clinical
outcome was assessed using the Mayo elbow performance score. We
calculated the revision rate and evaluated potential risk factors
for revision. The duration of follow-up was a mean 141 months (120
to 203).Aims
Materials and 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:
The number of revision total knee arthroplasties (TKA) that are
performed is expected to increase. However, previous reports of
the causes of failure after TKA are limited in that they report
the causes at specific institutions, which are often dependent on
referral patterns. Our aim was to report the most common indications
for re-operations and revisions in a large series of posterior-stabilised
TKAs undertaken at a single institution, excluding referrals from
elsewhere, which may bias the causes of failure. A total of 5098 TKAs which were undertaken between 2000 and 2012
were included in the study. Re-operations, revisions with modular
component exchange, and revisions with non-modular component replacement
or removal were identified from the medical records. The mean follow-up
was five years (two to 12).Aims
Patients and Methods
The aim of this study was to evaluate the long-term inducible
displacement of cemented tibial components ten years after total
knee arthroplasty (TKA). A total of 15 patients from a previously reported prospective
trial of fixation using radiostereometric analysis (RSA) were examined
at a mean of 11 years (10 to 11) postoperatively. Longitudinal supine
RSA examinations were acquired at one week, one year, and two years
postoperatively and at final follow-up. Weight-bearing RSA examinations
were also undertaken with the operated lower limb in neutral and
in maximum internal rotation positions. Maximum total point motion
(MTPM) was calculated for the longitudinal and inducible displacement examinations
(supine Aims
Patients and Methods
One goal of total hip arthroplasty is to restore normal hip anatomy.
The aim of this study was to compare displacement of the centre
of rotation (COR) using a standard reaming technique with a technique
in which the acetabulum was reamed immediately peripherally and
referenced off the rim. In the first cohort the acetabulum was reamed to the floor followed
by sequentially larger reamers. In the second cohort the acetabulum
was only reamed peripherally, starting with a reamer the same size
as the native femoral head. Anteroposterior pelvic radiographs were
analysed for acetabular floor depth and vertical and horizontal position
of the COR.Aims
Patients and Methods
Periprosthetic joint infection (PJI) remains a challenging complication
following total hip arthroplasty (THA). It is associated with high
levels of morbidity, mortality and expense. Guidelines and protocols
exist for the management of culture-positive patients. Managing
culture-negative patients with a PJI poses a greater challenge to
surgeons and the wider multidisciplinary team as clear guidance
is lacking. We aimed to compare the outcomes of treatment for 50 consecutive
culture-negative and 50 consecutive culture-positive patients who
underwent two-stage revision THA for chronic infection with a minimum
follow-up of five years.Aims
Patients and Methods
Enhanced micromotions between the implant and surrounding bone can impair osseointegration, resulting in fibrous encapsulation and aseptic loosening of the implant. Since the effect of micromotions on human bone cells is sparsely investigated, an Micromotions ranging from 25 µm to 100 µm were applied as sine or triangle signal with 1 Hz frequency to human osteoblasts seeded on collagen scaffolds. Micromotions were applied for six hours per day over three days. During the micromotions, a static pressure of 527 Pa was exerted on the cells by Ti6Al4V cylinders. Osteoblasts loaded with Ti6Al4V cylinders and unloaded osteoblasts without micromotions served as controls. Subsequently, cell viability, expression of the osteogenic markers collagen type I, alkaline phosphatase, and osteocalcin, as well as gene expression of osteoprotegerin, receptor activator of NF-κB ligand, matrix metalloproteinase-1, and tissue inhibitor of metalloproteinase-1, were investigated.Objectives
Methods
We present the ten-year data of a cohort of patients, aged between
18 and 65 years (mean age 52.7 years; 19 to 64), who underwent total
hip arthroplasty. Patients were randomised to be treated with a
cobalt-chrome (CoCr) femoral head with an ultra-high molecular weight
polyethylene (UHMWPE), highly cross-linked polyethylene (XLPE) or
ceramic-on-ceramic (CoC) bearing surface. A total of 102 hips (91 patients) were randomised into the three
groups. At ten years, 97 hips were available for radiological and
functional follow-up. Two hips (two patients) had been revised (one
with deep infection and one for periprosthetic fracture) and three
were lost to follow-up. Radiological analysis was performed using
a validated digital assessment programme to give linear, directional
and volumetric wear of the two polyethylene groups.Aims
Patients and Methods
The aim of this study was to determine whether the rates of revision
for metal-on-metal (MoM) total hip arthroplasties (THAs) with Pinnacle
components varied according to the year of the initial operation,
and compare these with the rates of revision for other designs of
MoM THA. Data from the National Joint Registry for England and Wales included
36 mm MoM THAs with Pinnacle acetabular components which were undertaken
between 2003 and 2012 with follow-up for at least five years (n
= 10 776) and a control group of other MoM THAs (n = 13 817). The
effect of the year of the primary operation on all-cause rates of revision
was assessed using Cox regression and interrupted time-series analysis.Aims
Patients and Methods
Bactericidal levels of antibiotics are difficult
to achieve in infected total joint arthroplasty when intravenous antibiotics
or antibiotic-loaded cement spacers are used, but intra-articular
(IA) delivery of antibiotics has been effective in several studies.
This paper describes a protocol for IA delivery of antibiotics in
infected knee arthroplasty, and summarises the results of a pharmacokinetic
study and two clinical follow-up studies of especially difficult
groups: methicillin-resistant Cite this article:
The outcome of 219 revision total hip arthroplasties
(THAs) in 98 male and 121 female patients, using 137 long length
and 82 standard length cemented collarless double-taper femoral
stems in 211 patients, with a mean age of 72 years (30 to 90) and
mean follow-up of six years (two to 18) have been described previously.
We have extended the follow-up to a mean of 13 years (8 to 20) in
this cohort of patients in which the pre-operative bone deficiency Paprosky
grading was IIIA or worse in 79% and 73% of femurs with long and
standard stems, respectively. For the long stem revision group, survival to re-revision for
aseptic loosening at 14 years was 97% (95% confidence interval (CI)
91 to 100) and in patients aged >
70 years, survival was 100%. Two
patients (two revisions) were lost to follow-up and 86 patients
with 88 revisions had died. Worst-case analysis for survival to
re-revision for aseptic loosening at 14 years was 95% (95% CI 89
to 100) and 99% (95% CI 96 to 100) for patients aged >
70 years. One
additional long stem was classified as loose radiographically but
not revised. For the standard stem revision group, survival to re-revision
for aseptic loosening at 14 years was 91% (95% CI 83 to 99). No
patients were lost to follow-up and 49 patients with 51 hips had
died. No additional stems were classified as loose radiographically. Femoral revision using a cemented collarless double-taper stem,
particularly with a long length stem, and in patients aged >
70
years, continues to yield excellent results up to 20 years post-operatively,
including in hips with considerable femoral metaphyseal bone loss. Cite this article:
Little biomechanical information is available about kinematically aligned (KA) total knee arthroplasty (TKA). The purpose of this study was to simulate the kinematics and kinetics after KA TKA and mechanically aligned (MA) TKA with four different limb alignments. Bone models were constructed from one volunteer (normal) and three patients with three different knee deformities (slight, moderate and severe varus). A dynamic musculoskeletal modelling system was used to analyse the kinematics and the tibiofemoral contact force. The contact stress on the tibial insert, and the stress to the resection surface and medial tibial cortex were examined by using finite element analysis.Objectives
Materials and Methods
The primary aim of this independent prospective randomised trial
was to compare serum metal ion levels for ceramic-on-metal (CoM)
and metal-on-metal (MoM) bearing surfaces in total hip arthroplasty
(THA). Our one-year results demonstrated elevation in metal ion
levels above baseline with no significant difference between the
CoM and MoM groups. This paper reviews the five-year data. The implants used in each patient differed only in respect to
the type of femoral head (ceramic or metal). At five-year follow-up
of the 83 enrolled patients, data from 67 (36 CoM, 31 MoM) was available
for comparison.Aims
Patients and Methods
